Impact of water table level on annual carbon and greenhouse gas balances of a restored peat extraction area

NASA Astrophysics Data System (ADS)

Järveoja, Järvi; Peichl, Matthias; Maddison, Martin; Soosaar, Kaido; Vellak, Kai; Karofeld, Edgar; Teemusk, Alar; Mander, Ülo

2016-05-01

Peatland restoration may provide a potential after-use option to mitigate the negative climate impact of abandoned peat extraction areas; currently, however, knowledge about restoration effects on the annual balances of carbon (C) and greenhouse gas (GHG) exchanges is still limited. The aim of this study was to investigate the impact of contrasting mean water table levels (WTLs) on the annual C and GHG balances of restoration treatments with high (ResH) and low (ResL) WTL relative to an unrestored bare peat (BP) site. Measurements of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes were conducted over a full year using the closed chamber method and complemented by measurements of abiotic controls and vegetation cover. Three years following restoration, the difference in the mean WTL resulted in higher bryophyte and lower vascular plant cover in ResH relative to ResL. Consequently, greater gross primary production and autotrophic respiration associated with greater vascular plant cover were observed in ResL compared to ResH. However, the means of the measured net ecosystem CO2 exchanges (NEE) were not significantly different between ResH and ResL. Similarly, no significant differences were observed in the respective means of CH4 and N2O exchanges. In comparison to the two restored sites, greater net CO2, similar CH4 and greater N2O emissions occurred in BP. On the annual scale, ResH, ResL and BP were C sources of 111, 103 and 268 g C m-2 yr-1 and had positive GHG balances of 4.1, 3.8 and 10.2 t CO2 eq ha-1 yr-1, respectively. Thus, the different WTLs had a limited impact on the C and GHG balances in the two restored treatments 3 years following restoration. However, the C and GHG balances in ResH and ResL were considerably lower than in BP due to the large reduction in CO2 emissions. This study therefore suggests that restoration may serve as an effective method to mitigate the negative climate impacts of abandoned peat extraction areas.

Peat resource definition and utilization in Massachusetts. Final report, Phase One

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brenninkmeyer, B.M.; Russo, J.S.

1984-10-01

To data less than five percent of Massachusetts peatlands have been developed. Ninety percent of the developed peatlands are located in the southeastern section of Massachusetts. Seventy-five percent of the developed peatlands are used for cranberry bogs. The remainder is used for horticultural peak extraction. At the present time peatland uses can be grouped into two types, consumptive and nonconsumptive. The primary consumptive uses are: (1) extraction of peat for use as or with industrial chemicals, (2) use by the horticultural industry and (3) most important under the DOE/MEOER Program, the use of peak as a fuel. The three usesmore » of peat under consumptive usage will require extraction or harvesting of peatlands. The main nonconsumptive uses are: (1) preservation of peatlands for conservation lands, (2) biomass production, (3) timber production and (4) the most important under the title of nonconsumptive uses is peatlands for agricultural crop production. These four uses require little or no peat extraction, harvesting or alteration of the wetlands. The selection and feasibility of one particular use over another is influenced by the significance of the economics and environmental concerns as well as the types and volumes of peat. 55 figures, 12 tables.« less

The peats of Costa Rica

DOE Office of Scientific and Technical Information (OSTI.GOV)

Obando A, L.; Malavassi R, L.; Ramirez E, O.

The objectives of this investigation were: (1) to locate potential peat deposits in Costa Rica; (2) to estimate as closely as possible by representative sampling the amount of peat present in each deposit, and (3) to make a preliminary evaluation of the quality of the peat in each deposit. With information from soil maps and a 3-week survey of Costa Rica, it is estimated that a potential area of about 1000 km{sup 2} is covered by peat. Most of the peat area (about 830 km{sup 2}) is in northeastern Costa Rica in the Tortuguero area. An aerial survey identified themore » potential peat areas by the exclusive presence of the Yolillo palm. The next largest potential area of peat (about 175 km{sup 2}) is in the cloud-covered areas of the Talamanca Mountains. Some reconnaissance has been done in the Talamanca Mountains, and samples of the peat indicate that it is very similar to the sphagnum peat moss found in Canada and the northern US. Smaller bogs have been discovered at Medio Queso, El Cairo, Moin, and the Limon airport. Two bogs of immediate interest are Medio Queso and El Cairo. The Medio Queso bog has been extensively sampled and contains about 182,000 metric tons (dry) of highly decomposed peat, which is being used as a carrier for nitrogen-fixing bacteria. The El Cairo bog is sparsely sampled and contains about 1,300,000 metric tons of slightly decomposed dry peat. Plans are to use this peat in horticultural applications on nearby farms. 10 refs., 11 figs., 7 tabs.« less

Extracted sweet corn tassels as a renewable alternative to peat in greenhouse substrates

USDA-ARS?s Scientific Manuscript database

Soilless substrates are primarily used in the production of containerized greenhouse and nursery crops. Sphagnum peat moss is a primary constituent of these substrates and its harvest from endangered ecosystems has become a worldwide concern. Ethanol-extracted, coarse-ground corn (Zea mays L. ‘Sil...

Derivation of greenhouse gas emission factors for peatlands managed for extraction in the Republic of Ireland and the United Kingdom

NASA Astrophysics Data System (ADS)

Wilson, D.; Dixon, S. D.; Artz, R. R. E.; Smith, T. E. L.; Evans, C. D.; Owen, H. J. F.; Archer, E.; Renou-Wilson, F.

2015-09-01

Drained peatlands are significant hotspots of carbon dioxide (CO2) emissions and may also be more vulnerable to fire with its associated gaseous emissions. Under the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol, greenhouse gas (GHG) emissions from peatlands managed for extraction are reported on an annual basis. However, the Tier 1 (default) emission factors (EFs) provided in the IPCC 2013 Wetlands Supplement for this land use category may not be representative in all cases and countries are encouraged to move to higher-tier reporting levels with reduced uncertainty levels based on country- or regional-specific data. In this study, we quantified (1) CO2-C emissions from nine peat extraction sites in the Republic of Ireland and the United Kingdom, which were initially disaggregated by land use type (industrial versus domestic peat extraction), and (2) a range of GHGs that are released to the atmosphere with the burning of peat. Drainage-related methane (CH4) and nitrous oxide (N2O) emissions as well as CO2-C emissions associated with the off-site decomposition of horticultural peat were not included here. Our results show that net CO2-C emissions were strongly controlled by soil temperature at the industrial sites (bare peat) and by soil temperature and leaf area index at the vegetated domestic sites. Our derived EFs of 1.70 (±0.47) and 1.64 (±0.44) t CO2-C ha-1 yr-1 for the industrial and domestic sites respectively are considerably lower than the Tier 1 EF (2.8 ± 1.7 t CO2-C ha-1 yr-1) provided in the Wetlands Supplement. We propose that the difference between our derived values and the Wetlands Supplement value is due to differences in peat quality and, consequently, decomposition rates. Emissions from burning of the peat (g kg-1 dry fuel burned) were estimated to be approximately 1346 CO2, 8.35 methane (CH4), 218 carbon monoxide (CO), 1.53 ethane (C2H6), 1.74 ethylene (C2H4), 0.60 methanol (CH3OH), 2.21 hydrogen cyanide (HCN) and 0.73 ammonia (NH3), and this emphasises the importance of understanding the full suite of trace gas emissions from biomass burning. Our results highlight the importance of generating reliable Tier 2 values for different regions and land use categories. Furthermore, given that the IPCC Tier 1 EF was only based on 20 sites (all from Canada and Fennoscandia), we suggest that data from another 9 sites significantly expand the global data set, as well as adding a new region.

Supplementation with a proprietary blend of ancient peat and apple extract may improve body composition without affecting hematology in resistance-trained men.

PubMed

Joy, Jordan M; Falcone, Paul H; Vogel, Roxanne M; Mosman, Matt M; Kim, Michael P; Moon, Jordan R

2015-11-01

Adenosine-5'-triphosphate (ATP) is primarily known as a cellular source of energy. Increased ATP levels may have the potential to enhance body composition. A novel, proprietary blend of ancient peat and apple extracts has been reported to increase ATP levels, potentially by enhancing mitochondrial ATP production. Therefore, the purpose of this investigation was to determine the supplement's effects on body composition when consumed during 12 weeks of resistance training. Twenty-five healthy, resistance-trained, male subjects (age, 27.7 ± 4.8 years; height, 176.0 ± 6.5 cm; body mass, 83.2 ± 12.1 kg) completed this study. Subjects supplemented once daily with either 1 serving (150 mg) of a proprietary blend of ancient peat and apple extracts (TRT) or placebo (PLA). Supervised resistance training consisted of 8 weeks of daily undulating periodized training followed by a 2-week overreach and a 2-week taper phase. Body composition was assessed using dual-energy X-ray absorptiometry and ultrasound at weeks 0, 4, 8, 10, and 12. Vital signs and blood markers were assessed at weeks 0, 8, and 12. Significant group × time (p < 0.05) interactions were present for ultrasound-determined cross-sectional area, which increased in TRT (+0.91 cm(2)) versus PLA (-0.08 cm(2)), as well as muscle thickness (TRT: +0.46; PLA: +0.04 cm). A significant group × time (p < 0.05) interaction existed for creatinine (TRT: +0.06; PLA: +0.15 mg/dL), triglycerides (TRT: +24.1; PLA: -20.2 mg/dL), and very-low-density lipoprotein (TRT: +4.9; PLA: -3.9 mg/dL), which remained within clinical ranges. Supplementation with a proprietary blend of ancient peat and apple extracts may enhance resistance training-induced skeletal muscle hypertrophy without affecting fat mass or blood chemistry in healthy males.

Contrasting denitrifier communities relate to contrasting N2O emission patterns from acidic peat soils in arctic tundra

PubMed Central

Palmer, Katharina; Biasi, Christina; Horn, Marcus A

2012-01-01

Cryoturbated peat circles (that is, bare surface soil mixed by frost action; pH 3–4) in the Russian discontinuous permafrost tundra are nitrate-rich ‘hotspots' of nitrous oxide (N2O) emissions in arctic ecosystems, whereas adjacent unturbated peat areas are not. N2O was produced and subsequently consumed at pH 4 in unsupplemented anoxic microcosms with cryoturbated but not in those with unturbated peat soil. Nitrate, nitrite and acetylene stimulated net N2O production of both soils in anoxic microcosms, indicating denitrification as the source of N2O. Up to 500 and 10 μ nitrate stimulated denitrification in cryoturbated and unturbated peat soils, respectively. Apparent maximal reaction velocities of nitrite-dependent denitrification were 28 and 18 nmol N2O gDW−1 h−1, for cryoturbated and unturbated peat soils, respectively. Barcoded amplicon pyrosequencing of narG, nirK/nirS and nosZ (encoding nitrate, nitrite and N2O reductases, respectively) yielded ≈49 000 quality-filtered sequences with an average sequence length of 444 bp. Up to 19 species-level operational taxonomic units were detected per soil and gene, many of which were distantly related to cultured denitrifiers or environmental sequences. Denitrification-associated gene diversity in cryoturbated and in unturbated peat soils differed. Quantitative PCR (inhibition-corrected per DNA extract) revealed higher copy numbers of narG in cryoturbated than in unturbated peat soil. Copy numbers of nirS were up to 1000 × higher than those of nirK in both soils, and nirS nirK−1 copy number ratios in cryoturbated and unturbated peat soils differed. The collective data indicate that the contrasting N2O emission patterns of cryoturbated and unturbated peat soils are associated with contrasting denitrifier communities. PMID:22134649

Low-rank coal study: national needs for resource development. Volume 6. Peat

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1980-11-01

The requirements and potential for development of US peat resources for energy use are reviewed. Factors analyzed include the occurrence and properties of major peat deposits; technologies for extraction, dewatering, preparation, combustion, and conversion of peat to solid, liquid, or gaseous fuels; environmental, regulatory, and market constraints; and research, development, and demonstration (RD and D) needs. Based on a review of existing research efforts, recommendations are made for a comprehensive national RD and D program to enhance the use of peat as an energy source.

Impact of water table level on annual carbon and greenhouse gas balances of a restored peat extraction area

NASA Astrophysics Data System (ADS)

Järveoja, J.; Peichl, M.; Maddison, M.; Soosaar, K.; Vellak, K.; Karofeld, E.; Teemusk, A.; Mander, Ü.

2015-10-01

Peatland restoration may provide a potential after-use option to mitigate the negative climate impact of abandoned peat extraction areas; currently, however, knowledge about restoration effects on the annual balances of carbon (C) and greenhouse gas (GHG) exchanges is still limited. The aim of this study was to investigate the impact of contrasting water table levels (WTL) on the annual C and GHG balances of restoration treatments with high (Res-H) and low (Res-L) WTL relative to an unrestored bare peat (BP) site. Measurements of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes were conducted over a full year using the closed chamber method and complemented by measurements of abiotic controls and vegetation cover. Three years following restoration, the difference in the mean WTL resulted in higher bryophyte and lower vascular plant cover in Res-H relative to Res-L. Consequently, greater gross primary production and autotrophic respiration associated with greater vascular plant cover were observed in Res-L compared to Res-H. However, the means of the measured net ecosystem CO2 exchanges (NEE) were not significantly different between Res-H and Res-L. Similarly, no significant differences were observed in the respective means of CH4 and N2O exchanges in Res-H and Res-L, respectively. In comparison to the two restored sites, greater net CO2, similar CH4 and greater N2O emissions occurred in BP. On the annual scale, Res-H, Res-L and BP were C sources of 111, 103 and 268 g C m-2 yr-1 and had positive GHG balances of 4.1, 3.8 and 10.2 t CO2 eq ha-1 yr-1, respectively. Thus, the different WTLs had a limited impact on the C and GHG balances in the two restored treatments three years following restoration. However, the C and GHG balances in Res-H and Res-L were considerably lower than in BP owing to the large reduction in CO2 emissions. This study therefore suggests that restoration may serve as an effective method to mitigate the negative climate impacts of abandoned peat extraction areas.

[The release of biologically active compounds from peat peloids].

PubMed

Babaskin, D V

2011-01-01

This work had the objective to study kinetics of the release of flavonoides from peat peloid compositions containing extracts of medicinal herbs in model systems.The key parameters of the process are defined. The rate of liberation of flavonoides is shown to depend on their initial concentration in the compositions being used. The influence of the flavonoide composition of the tested extracts and dimethylsulfoxide on the release of biologically active compounds contained in the starting material in the model environment is estimated. The possibility of the layer-by-layer deposition of the compositions and peat peloids in order to increase the efficacy of flavonoide release from the starting composition and to ensure more rational utilization of the extracts of medicinal plants is demonstrated.

Temperature-driven adaptation of the bacterial community in peat measured by using thymidine and leucine incorporation.

PubMed

Ranneklev, S B; Bååth, E

2001-03-01

The temperature-driven adaptation of the bacterial community in peat was studied, by altering temperature to simulate self-heating and a subsequent return to mesophilic conditions. The technique used consisted of extracting the bacterial community from peat using homogenization-centrifugation and measuring the rates of thymidine (TdR) or leucine (Leu) incorporation by the extracted bacterial community at different temperatures. Increasing the peat incubation temperature from 25 degrees C to 35, 45, or 55 degrees C resulted in a selection of bacterial communities whose optimum temperatures for activity correlated to the peat incubation temperatures. Although TdR and Leu incorporations were significantly correlated, the Leu/TdR incorporation ratios were affected by temperature. Higher Leu/TdR incorporation ratios were found at higher temperatures of incubation of the extracted bacterial community. Higher Leu/TdR incorporation ratios were also found for bacteria in peat samples incubated at higher temperatures. The reappearance of the mesophilic community and disappearance of the thermophilic community when the incubation temperature of the peat was shifted down were monitored by measuring TdR incorporation at 55 degrees C (thermophilic activity) and 25 degrees C (mesophilic activity). Shifting the peat incubation temperature from 55 to 25 degrees C resulted in a recovery of the mesophilic activity, with a subsequent disappearance of the thermophilic activity. The availability of substrate for bacterial growth varied over time and among different peat samples. To avoid confounding effects of substrate availability, a temperature adaptation index was calculated. This index consisted of the log(10) ratio of TdR incorporation at 55 and 25 degrees C. The temperature index decreased linearly with time, indicating that no thermophilic activity would be detected by the TdR technique 1 month after the temperature downshift. There were no differences between the slopes of the temperature adaptation indices over time for peat samples incubated at 55 degrees C 3 or 11 days before incubation at 25 degrees C. Thus, different levels of bacterial activity did not affect the temperature-driven adaptation of the bacterial community.

Temperature-Driven Adaptation of the Bacterial Community in Peat Measured by Using Thymidine and Leucine Incorporation

PubMed Central

Ranneklev, Sissel Brit; Bååth, Erland

2001-01-01

The temperature-driven adaptation of the bacterial community in peat was studied, by altering temperature to simulate self-heating and a subsequent return to mesophilic conditions. The technique used consisted of extracting the bacterial community from peat using homogenization-centrifugation and measuring the rates of thymidine (TdR) or leucine (Leu) incorporation by the extracted bacterial community at different temperatures. Increasing the peat incubation temperature from 25°C to 35, 45, or 55°C resulted in a selection of bacterial communities whose optimum temperatures for activity correlated to the peat incubation temperatures. Although TdR and Leu incorporations were significantly correlated, the Leu/TdR incorporation ratios were affected by temperature. Higher Leu/TdR incorporation ratios were found at higher temperatures of incubation of the extracted bacterial community. Higher Leu/TdR incorporation ratios were also found for bacteria in peat samples incubated at higher temperatures. The reappearance of the mesophilic community and disappearance of the thermophilic community when the incubation temperature of the peat was shifted down were monitored by measuring TdR incorporation at 55°C (thermophilic activity) and 25°C (mesophilic activity). Shifting the peat incubation temperature from 55 to 25°C resulted in a recovery of the mesophilic activity, with a subsequent disappearance of the thermophilic activity. The availability of substrate for bacterial growth varied over time and among different peat samples. To avoid confounding effects of substrate availability, a temperature adaptation index was calculated. This index consisted of the log10 ratio of TdR incorporation at 55 and 25°C. The temperature index decreased linearly with time, indicating that no thermophilic activity would be detected by the TdR technique 1 month after the temperature downshift. There were no differences between the slopes of the temperature adaptation indices over time for peat samples incubated at 55°C 3 or 11 days before incubation at 25°C. Thus, different levels of bacterial activity did not affect the temperature-driven adaptation of the bacterial community. PMID:11229900

Radioactivity of natural medicinal preparations contained extracts from peat mud available in retail trade used externally.

PubMed

Karpińska, Maria; Kapała, Jacek; Raciborska, Agnieszka; Kulesza, Grzegorz; Milewska, Anna; Mnich, Stanisław

2017-08-01

In this work were identified and measured the activity of radioactive isotopes present in medicinal preparations from peat mud and estimated the doses obtained from them during therapy. Radioactivity of 22 preparations from peat mud and 20 water samples from water of the North-East region of Poland was studied. The median of the total activity was 24.8 Bq kg -1 . Total maximal isotope activity was observed in the Iwonicka Cube 146 Bq kg -1 while considerable amounts of isotopes were found in the Kolobrzeska Peat Mud Paste 112 Bq kg -1 . The doses obtained during therapy were within the range of 11 nSv-13 μSv depending on extracts of medicinal preparations from peat mud. The probability that such a small dose would stimulate biological effects is low. However, some clinicians believe that one of the possible therapeutic mechanisms in the treatment of rheumatoid disorders is the induction of immune response by ionising radiation.

SPRUCE Deep Peat Heating (DPH) Peat Water Content and Temperature Profiles for Experimental Plot Cores, June 2014 through June 2015

DOE Data Explorer

Kluber, Lauren A. [Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.; Phillips, Jana R. [Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.; Hanson, Paul J. [Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.; Schadt, Christopher W. [Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.

2016-01-01

This data set provides the peat water content and peat temperature at time of sampling for peat cores collected before and during the SPRUCE Deep Peat Heating (DPH) study. Cores were collected during three sampling events: 03 June 2014, 09 September 2014, and 16 June 2015. Two cores were extracted from hollow locations in each of the 10 experimental plots (4, 6, 8, 10, 11, 13, 16, 17, 19, and 20). Cores were partitioned into samples at 11 depth increments: 0-10, 10-20, 20-30, 30-40, 40-50, 50-75, 75-100, 100-125, 125-150, 150-175, and 175-200 cm below surface of the hollow.

Determination of low methylmercury concentrations in peat soil samples by isotope dilution GC-ICP-MS using distillation and solvent extraction methods.

PubMed

Pietilä, Heidi; Perämäki, Paavo; Piispanen, Juha; Starr, Mike; Nieminen, Tiina; Kantola, Marjatta; Ukonmaanaho, Liisa

2015-04-01

Most often, only total mercury concentrations in soil samples are determined in environmental studies. However, the determination of extremely toxic methylmercury (MeHg) in addition to the total mercury is critical to understand the biogeochemistry of mercury in the environment. In this study, N2-assisted distillation and acidic KBr/CuSO4 solvent extraction methods were applied to isolate MeHg from wet peat soil samples collected from boreal forest catchments. Determination of MeHg was performed using a purge and trap GC-ICP-MS technique with a species-specific isotope dilution quantification. Distillation is known to be more prone to artificial MeHg formation compared to solvent extraction which may result in the erroneous MeHg results, especially with samples containing high amounts of inorganic mercury. However, methylation of inorganic mercury during the distillation step had no effect on the reliability of the final MeHg results when natural peat soil samples were distilled. MeHg concentrations determined in peat soil samples after distillation were compared to those determined after the solvent extraction method. MeHg concentrations in peat soil samples varied from 0.8 to 18 μg kg(-1) (dry weight) and the results obtained with the two different methods did not differ significantly (p=0.05). The distillation method with an isotope dilution GC-ICP-MS was shown to be a reliable method for the determination of low MeHg concentrations in unpolluted soil samples. Furthermore, the distillation method is solvent-free and less time-consuming and labor-intensive when compared to the solvent extraction method. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of peat fires on the characteristics of humic acid extracted from peat soil in Central Kalimantan, Indonesia.

PubMed

Yustiawati; Kihara, Yusuke; Sazawa, Kazuto; Kuramitz, Hideki; Kurasaki, Masaaki; Saito, Takeshi; Hosokawa, Toshiyuki; Syawal, M Suhaemi; Wulandari, Linda; Hendri I; Tanaka, Shunitz

2015-02-01

When peat forest fires happen, it leads to burn soil and also humic acids as a dominant organic matter contained in peat soil as well as the forest. The structure and properties of humic acids vary depending on their origin and environment, therefore the transformation of humic acid is also diverse. The impacts of the peat fires on peat soil from Central Kalimantan, Indonesia were investigated through the characterization of humic acids, extracted from soil in burnt and unburnt sites. The characterization of humic acids was performed by elemental composition, functional groups, molecular weight by HPSEC, pyrolysate compounds by pyrolysis-GC/MS, fluorescence spectrum by 3DEEM spectrofluorometer, and thermogravimetry. The elemental composition of each humic substance indicated that the value of H/C and O/C of humic acids from burnt sites were lower than that from unburnt sites. The molecular weight of humic acids from burnt sites was also lower than that from unburnt sites. Pyrolysate compounds of humic acids from unburnt sites differed from those of humic acids from burnt soil. The heating experiment showed that burning process caused the significant change in the properties of humic acids such as increasing the aromaticity and decreasing the molecular weight.

ROUND LAKE WILDERNESS STUDY AREA, WISCONSIN.

USGS Publications Warehouse

Cannon, W.F.; Williams, Bradford B.

1984-01-01

The Round Lake Wilderness study area in Wisconsin was studied using geophysical and geochemical surveys, examination of a few bedrock exposures near the area (none are known within the area) and augering and testing of peat deposits. The only direct indication of potential mineral resource is about 760,000 tons of commercial quality peat contained in several bogs. Larger deposits of similar material are abundant closer to markets and although the peat in this area is classified as a demonstrated resource within an area of substantiated peat resource potential, it is considered to be of little importance. The study area lies within a belt of ancient volcanic rocks extending across northern Wisconsin in which several important copper, zinc, and lead deposits were discovered but no indication of such deposits was found within the area.

Only low methane production and emission in degraded peat extraction sites after rewetting

NASA Astrophysics Data System (ADS)

Agethen, Svenja; Waldemer, Carolin; Knorr, Klaus-Holger

2015-04-01

In Central Europe rewetting of bogs after peat extraction is a wide spread technique to halt secondary aerobic decomposition and to reestablish plant species such as Sphagnum spp. and Eriophorum spp. that initialize accumulation of organic carbon in peat. Before extraction, such sites are often used for agriculture causing the aerobic degradation of peat and mobilization of phosphorus, ammonia, and dissolved organic matter (DOM). In nutrient poor ecosystems such as bogs, additional supply of P and N does not only trigger the establishment of uncharacteristic vegetation but also the formation of more labile plant litter and DOM that is readily degradable. Therefore, after rewetting and the development of anoxic conditions especially in initial stages high methane (CH4) emissions are reported for these systems compared to pristine bogs. Regarding the potential of methane production and emissions we investigated three common practices to prepare extraction fields for restoration (years since rewetting): i) Filling of drainage ditches, passive rewetting (1 site, Altendorfer Moor, Stade, NW-Germany, ca. 20 yr.), ii) Removal of upper 30 cm peat layer, removed peat used for construction of polder dikes (2 sites, Königsmoor, Leer, NW-Germany, 2 and 3 yr.), iii) Removal upper peat layer down to 50 cm grown peat, not extracted peat used as polder walls (2 sites, Benthullener Moor, Wardenburg, NW-Germany, 3 and 7 yr.). In each site two vegetated replicate mesocosms (diam. 30 cm, depth 40 cm) were sampled and placed in a greenhouse from May-October 2014 to maintain the water table at surface level. Pore water concentrations of ions, fermentation products and DOM, DOM electron acceptor capacity (EAC), soil gas concentrations of CO2, CH4 and H2, gas fluxes as well as element composition and organic matter quality of DOM and SOM were analyzed. We found out that practice i) with least efforts of nutrient removal in the peat produced the highest CH4 emissions (3.5 mmol m-2 d-1) although still within the range of northern pristine bogs. Also practice ii) showed still inputs of external nutrients and labile DOM, but CH4 production was not yet developed (0.23 and 0.07 mmol m-2 d-1). Practice iii) was most effective in nutrient removal, but only in the 7 yr. site little methane (in the 3 yr. site 0.025 vs. 0.41 mmol m-2 d-1in the 7 yr. site) was emitted. The emissions were well in accord with soil gas concentrations, maximum values for CH4 in practice i) were 115 μmol L-1, 2-5 μmol L-1 in practice ii) and 0.5 vs. 16 μmol L-1 in practice iii). Only small concentrations of inorganic electron acceptors such as sulfate imply the importance of organic matter as electron acceptor. The results show that restored bogs on former strongly degraded extraction fields do not necessarily act as exceptionally high CH4 sources. Contrary to other findings in early stages of rewetting CH4 emissions can also be very low until other electron acceptors are exhausted and methanogens become effective competitors for substrates which happens in the order of years.

The impact of 90 years of drainage works on some chemical properties of raised peat bog organic soils - case study from valley of the Upper San river in Polish Bieszczady Mts. (Eastern Carpathians).

NASA Astrophysics Data System (ADS)

Stolarczyk, Mateusz

2016-04-01

Wetland ecosystems, including raised peat bogs are characterized by a specific water conditions and unique vegetation, which makes peatland highly important habitats due to protection of biodiversity. Transformation of peat bog areas is particularly related to changes in the environment e.g. according to reclamation works. Drainage of peatlands is directly associated to the decrease of groundwater levels and lead to a number of changes in the chemical and physical properties of peat material, included contents of exchangeable cations in the surface layers of peat soils in the decession phase of peat development and release above compounds from the soil to ground or surface waters. The aim of the research was to determine the impact of extended drainage works on chemical composition of sorption complex of raised peat bog organic soils and identification the potential environmental effects of alkaline cations leaching to the surface waters. Research was carried out on the peat bogs located in the Upper San valley in Polish Bieszczady Mts. (Eastern Carpathians). Soil samples used in this study were collected from 3 soil profiles in 10 or 20 cm intervals to the approximately 130 cm depth. Laboratory analyses included determination of basic properties of organic material such as the degree of peat decomposition, ash content, soil pH and carbon, hydrogen, nitrogen concentrations. Additionally the amount of alkaline cations, exchangeable and extractable acidity was determined. Furthermore, the degree of saturation of the sorption complex with alkaline cations (V) and cation exchange capacity (CEC) are calculated. In order to evaluate the impact of the examined peat bog to the environment, also water samples were collected and ions composition was measured. The obtained results show that studied organic soils are oligotrophic and strongly acidic. In the case of organic material related to decession phase of peat development, as a result of the lengthy drainage works, increased pH values, changes in the morphology of the peat, high nitrogen contents and lower values of C/N ratios are noticed. The increased contents of calcium, occurred in soil layers comprised of moorsh forming process are probably the effect of peat mineralization process or changes in the chemistry and fluctuations of groundwater levels. As a result of above factors, increased calcium and magnesium concentrations in surface waters in the immediate vicinity of investigated bogs are observed.

RAINBOW LAKE WILDERNESS AND FLYNN LAKE WILDERNESS STUDY AREA, WISCONSIN.

USGS Publications Warehouse

Cannon, W.F.; Dunn, Maynard L.

1984-01-01

The Rainbow Lake Wilderness and Flynn Lake Wilderness study area in Wisconsin are contiguous and were studied as a unit. The rainbow Lake Wilderness contains a demonstrated resource of about 210,000 tons of commercial-quality peat in an area of substantiated peat resource potential. The Flynn Lake Wilderness study area contains a demonstrated resource of about 300,000 tons of commercial-quality peat in an area of substantiated peat resource potential. These deposits, however, are of limited importance because larger deposits of similar material are abundant outside the areas, closer to present markets. Rocks in the subsurface contain a low-grade copper resource identified by mining company exploration drilling. Although this is an area of substantiated copper resource potential, it is a low-grade resource, thin and generally at great depth.

Investigation of metal ions sorption of brown peat moss powder

NASA Astrophysics Data System (ADS)

Kelus, Nadezhda; Blokhina, Elena; Novikov, Dmitry; Novikova, Yaroslavna; Chuchalin, Vladimir

2017-11-01

For regularities research of sorptive extraction of heavy metal ions by cellulose and its derivates from aquatic solution of electrolytes it is necessary to find possible mechanism of sorption process and to choice a model describing this process. The present article investigates the regularities of aliovalent metals sorption on brown peat moss powder. The results show that sorption isotherm of Al3+ ions is described by Freundlich isotherm and sorption isotherms of Na+ i Ni2+ are described by Langmuir isotherm. To identify the mechanisms of brown peat moss powder sorption the IR-spectra of the initial brown peat moss powder samples and brown peat moss powder samples after Ni (II) sorption were studied. Metal ion binding mechanisms by brown peat moss powder points to ion exchange, physical adsorption, and complex formation with hydroxyl and carboxyl groups.

Mitigation of greenhouse gas emission on abandoned peatlands by growing reed canary grass

NASA Astrophysics Data System (ADS)

Järveoja, J.; Laht, J.; Soosaar, K.; Maddison, M.; Ostonen, I.; Mander, Ü.

2012-04-01

We used combined closed-chamber and plant biomass techniques to study the impact of reed canary grass (RCG, Phalaris arundinacea) cultivation on greenhouse gas (GHG) fluxes and carbon balance of an abandoned peat extraction area in Lavassaare, Estonia (N58°34'20''; E24°23'15''). Three core study sites were chosen within the abandoned peat extraction area: (I) bare peat soil (abandoned and not planted site), (II) non-fertilized Phalaris site, (III) and fertilized Phalaris site (all on drained Fibric Histosols). In addition, (IV) the natural raised bog (Fibric Histosol) and (V) the cultivated fen meadow (drained Sapric Histosol) served as reference sites. The CO2, CH4 and N2O fluxes were determined using the closed-chamber method once a month from May 2010 to December 2011. White 60 L chambers made of PVC and sealed with a water-filled ring on the soil surface were installed in 5 replicates on each site. The gas was sampled 3 times per hour in 100 mL pre-evacuated glass bottles, and in the lab the gas concentrations were measured using the Shimadzu GC-2014 (ECD, FID) gas-chromatographic system combined with a Loftfield autosampler. Measurements of groundwater level and soil temperature (10, 20, 30, and 40 cm depths) were performed simultaneously. Biomass assessments of RCG were carried out just after maximal growth of macrophytes, in early September 2010, in April 2011 just after snow melt (time of minimum aboveground biomass), and again in September 2011. Aboveground biomass samples were collected from 1×1m plots. Belowground biomass samples were collected at a depth of 25 cm in 3 replicates adjacent to each chamber using a 10×10 cm auger. Samples were analyzed for N, P and C. Our results showed high nitrous oxide emissions (up to 541 μg N2O-N m-2 h-1) from the fen meadow and high methane emissions from the natural raised bog (up to 12915 μg CH4-C m-2 h-1). The low CH4 emission from the Phalaris plots and bare soil was due to the deeper water table (up to 85 cm below ground) and high sulfur concentration in peat (up to 23 g kg-1), which probably inhibited methanogenesis. The high CO2 emission on fertilized and non-fertilized Phalaris plots in comparison to the bare peat site was probably caused by: (1) the higher plant biomass: more dissolved C coming from roots and greater amount of fine root turnover, (2) the influence of fresh plant litter on the peat mineralization on Phalaris plots, and (3) inhibited mineralization by recalcitrant C of bare peat. Our results demonstrated that as a total, the Phalaris sites acted as net carbon sinks, sequestering C in the amount of 6929.5 and 6083.5 kg CO2-C ha-1 yr-1 on the fertilized and non-fertilized plots, respectively, whereas the bare peat site acted as a carbon source (emitting 687.5 kg CO2-C ha-1 yr-1).

Changes in vegetation, peat properties and peat accumulation in Swedish peatlands as revealed by archive data.

NASA Astrophysics Data System (ADS)

Schoning, Kristian; Sohlenius, Gustav

2016-04-01

In this investigation we have studied patterns in peat accumulation and changes in mire status since the early 1900s for two areas in Sweden. In the early 1900s the Geological Survey of Sweden collected a vast amount of peat and peatland data, including information on vegetation and land-use. We have used this archive data to evaluate changes in mire vegetation, mire wetness and surface peat properties, rates of peat accumulation, succession in young wetlands and the effects of cultivation on peatlands. In total 156 mires in an uplift area of eastern middle Sweden were included in the data-set, including both pristine mires and peatlands used for agricultural purposes. In this area new peatlands have continuously been formed during the past 7 000 years making it possible to evaluate changes in peat accumulation over time. The other study area is situated in the south Swedish Uplands where we have revisited some larger bogs. The results from our investigation show that many of the peatlands have underwent major changes since the early 1900s. In most of the small peatlands we have found important changes in vegetation where mire vegetation has been replaced by nutrient demanding and/or dry species flora while the tree stand on large mires in south Sweden have increased. In some mires humification has increased in the uppermost peat-layers and the mire surface have become drier compared to the early 1900s. In eastern middle Sweden there are indications that the peat accumulation is lower 0,5 mm/year in older peatlands compared with younger ones 1,2 mm/year, although the mire vegetation in the older peatlands is dominated by sphagnum. The peat depth of the cultivated mires in this area shows a mean decrease of 40 cm since the early 1900s.

Investigation of bacterial communities in peat land of the Gahai Lake natural conservation area

NASA Astrophysics Data System (ADS)

Bai, Yani; Wang, Jinchang; Zhan, Zhigao; Guan, Limei; Jin, Liang; Zheng, Guohua

2017-10-01

Peat is involved in the global carbon cycle and water conservation; therefore, it is implicated in global environmental change. Microorganisms play an important role in the function of peat. To investigate the bacterial communities in peat of Gahai Lake, different locations and depths were sampled and Illumina Miseq sequencing was used to analyze the microbial community. Chemical properties of peat samples were analyzed by China state standard methods (GB methods). The results showed that bacterial communities were affected by depth, with bacterial diversity and community structure at 90 and 120 cm significantly different from that at 10, 30 and 50 cm depth from the peat surface. Chemical properties of peat land including organic matter, total nitrogen and humus content did not significantly influence bacterial community structure in peat, with only one group from genus Rhizomicrobium that was significantly correlated with total nitrogen. A substantial proportion of the bacterial sequences were unclassified (1.4%), which indicates the great application potential of peat in the Gahai Lake natural conservation area in the future.

The Characteristics of Peats and Co2 Emission Due to Fire in Industrial Plant Forests

NASA Astrophysics Data System (ADS)

Ratnaningsih, Ambar Tri; Rayahu Prasytaningsih, Sri

2017-12-01

Riau Province has a high threat to forest fire in peat soils, especially in industrial forest areas. The impact of fires will produce carbon (CO2) emissions in the atmosphere. The magnitude of carbon losses from the burning of peatlands can be estimated by knowing the characteristics of the fire peat and estimating CO2 emissions produced. The objectives of the study are to find out the characteristics of fire-burning peat, and to estimate carbon storage and CO2 emissions. The location of the research is in the area of industrial forest plantations located in Bengkalis Regency, Riau Province. The method used to measure peat carbon is the method of lost in ignation. The results showed that the research location has a peat depth of 600-800 cm which is considered very deep. The Peat fiber content ranges from 38 to 75, classified as hemic peat. The average bulk density was 0.253 gram cm-3 (0.087-0,896 gram cm-3). The soil ash content is 2.24% and the stored peat carbon stock with 8 meter peat thickness is 10723,69 ton ha-1. Forest fire was predicted to burn peat to a depth of 100 cm and produced CO2 emissions of 6,355,809 tons ha-1.

Analysis of volatile organic compound from Elaeis guineensis inflorescences planted on different soil types in Malaysia

NASA Astrophysics Data System (ADS)

Muhamad Fahmi, M. H.; Ahmad Bukhary, A. K.; Norma, H.; Idris, A. B.

2016-11-01

The main attractant compound for Eleidobius kamerunicus to male spikelet Elaeis guineensis (oil palm) were determined by analyzing volatile organic compound extracted from E. guineenses inflorescences planted on different soil types namely peat soil, clay soil and sandy soil. Anthesizing male oil palm inflorescences were randomly choosen from palm aged between 4-5 years old age. Extraction of the volatiles from the oil palm inflorescences were performed by Accelerated Solvent Extraction method (ASE). The extracted volatile compound were determined by using gas chromatography-mass spectrometry. Out of ten identified compound, estragole was found to be a major compound in sandy soil (37.49%), clay soil (30.71%) and peat soil (27.79%). Other compound such as 9,12-octadecadieonic acid and n-hexadecanoic acid were found as major compound in peat soil (27.18%) and (7.45%); sandy soil (14.15 %) and (9.31%); and clay soil (30.23%) and (4.99%). This study shows that estragole was the predominant volatile compound detected in oil palm inflorescences with highly concentrated in palm planted in sandy soil type.

Effects of Eriophorum vaginatum on N_{2}O emissions at a restored peatland

NASA Astrophysics Data System (ADS)

Brummell, Martin; Lazcano, Cristina; Strack, Maria

2016-04-01

Restoration of peatlands extracted for horticultural peat production includes both deliberate and accidental introduction of a wide range of plant species, including vascular plants and bryophytes. The roots of vascular plants provide a channel for the movement of greenhouse gases (GHG) including N2O in many soil ecosystems, and may stimulate production of N2O or have other effects via the release of root exudates that are then taken up by soil microorganisms such as heterotrophic denitrifiers. Here we carried out a field study in order to evaluate the effects of Eriophorum vaginatum, an abundant sedge at the harvested peatland at Seba Beach, Alberta, Canada, (53° 27'17.2"N 114° 52'52.0"W) where restoration efforts began in late 2012, and is the dominant ground cover in some areas. We hypothesized that E. vaginatum would increase net N2O production from peat compared to areas of bare peat or moss. We measured net GHG exchange for CO2, CH4, and N2O over one growing season (May-September 2015) using static chambers within this peatland to compare between plots containing E. vaginatum and plots lacking vascular plants. Plots were located along a transect of increasing water table, in order to discriminate between the effects of E. vaginatum and the prevailing hydrological conditions on N2O fluxes. Net fluxes of N2O from the peat to the atmosphere were observed throughout the experimental area, as well as fluxes in the opposite direction, in which the peat removed N2O from the atmosphere inside the chamber. Non-zero fluxes were highly variable in both occurrence and magnitude, though a small number of plots accounted for the majority of measured fluxes. Neither aboveground biomass of E. vaginatum nor its presence in a plot was correlated with either frequency or direction of N2O flux measurements. Other factors, such as water table fluctuations and temperature may be stronger drivers of these microbially-mediated processes than vegetation at this stage of the restoration.

Chemical characterization of biochar and assessment of the nutrient dynamics by means of preliminary plant growth tests.

PubMed

Prasad, Munoo; Tzortzakis, Nikos; McDaniel, Nicola

2018-06-15

Biochar can be produced from several organic sources with varying nutrients and metal concentrations. Four commercial grade biochars were evaluated as peat substitute. Biochars were characterised for plant nutrients and for biological stability. The results showed that there were negligible quantities of N and P and generally high levels of K and high biological stability. When these materials were mixed with peat at 10, 25 and 50% and nutrients were added to bring them to the same level of nutrients as in fertilized peat, it was found that biochar mixtures considerably reduced the levels of calcium chloride/DTPA (CAT) extractable N (including nitrate), P, and electrical conductivity- greater extent with higher rates of biochar addition except for K. The pH and K levels were increased with biochar addition. The drop in EC has important implications regarding the use of other materials used to dilute peat, for example, composted green waste, the rate of dilution is limited due to high EC and biochar addition gives the potential for higher peat dilution of these materials. Nitrate and phosphorus are very vulnerable to leaching of these nutrients in the environment in peat substrates and the binding of these by biochar has implication for leaching and nutrient application strategy. Root development using Cress test and tomato plant height and biomass using containers, were in some cases better than peat indicating that biochar could be used to dilute peat e.g. for seedling production where root development and rapid growth are very important. Application of biochars resulted in a marked reduction of N (and P) in the plant. There were significant correlation between CAT extractable N and P and corresponding plant concentration, indicating the standard growing media test, CAT, would be suitable for assessing the nutrient status of peat biochar mixes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Influence of a step-change increase of peat moisture content on the horizontal propagation of smouldering fires

NASA Astrophysics Data System (ADS)

Prat-Guitart, Nuria; Belcher, Claire M.; Hadden, Rory M.; Rein, Guillermo; Yearsley, Jon M.

2015-04-01

In shallow layers of peat, the transition between moss species causes a step-change of the horizontal distribution of peat moisture content. Post-fire studies in peatlands have reported shallow layers being consumed in irregular distributions. The unburned areas were found to be patches of wet Sphagnum moss. Our laboratory scale study analyses the effect of a horizontal step-change in moisture content on the spread of smouldering. We designed a laboratory-scale experiment (20×18×5 cm) within an insulated box filled with milled peat. Peat was ignited on one side of the box from which the smouldering fire horizontally self-propagates through a region of dry peat (MC1) and then through a wetter region of peat (MC2). An infrared camera, a webcam and thermocouples monitor the position of the smouldering fire spreading horizontally. The experiment was repeated with peats at different moisture content combinations to analyse the smouldering behaviour on a range of moisture content step-change conditions. The data analysis estimates the burned area and examines smouldering fire behaviour across a wide range of moisture content combinations reproducing realistic scenarios. We found that the area burned depends on peat moisture content before the step-change (MC1) as well as the increase in moisture of the step-change itself (difference between MC1 and MC2). Our study assists in researching the influence of peat moisture content on the spread of smouldering in peatland fire and contributes to a better understanding of the post-fire peatland landscape, helping to reconstruct smouldering fire events.

Economic characteristics of the peat deposits of Costa Rica: preliminary study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cohen, A.D. Malavassi, L.; Raymond, R. Jr.; Mora, S.

1985-01-01

Recent field and laboratory studies have established the presence of numerous extensive peat deposits in Costa Rica. Three of these were selected for initial investigation: (1) the cloud-forest histosols of the Talamanca Mountain Range; (2) the Rio Medio Queso flood plain deposits near the northern Costa Rican border; and (3) a tropical jungle swamp deposit on the northeastern coastal plain. In the Talamanca area, 29 samples were collected from eight sites. Due to the high moisture and cool temperatures of the cloud forest, the peats in this area form blanket-like deposits (generally <1 meter thick) over a wide area (>150more » km/sup 2/). These peats are all highly decomposed (avg. 28% fiber), high in ash (avg. 21%), and extensively bioturbated. Relative to all other sites visited, these peats are lowest in moisture (avg. 84%), pH (avg. 4.4), fixed carbon (avg. 23%), and sulfur (avg. 0.2%). However, they have the highest bulk densities (avg. 0.22 g/cc), volatile matter contents (avg. 55%), and nitrogen. Their heating value averaged 7700 BTUs/lb., dry. In the Rio Medio Queso area, 28 samples were collected, representing one transect of the 70 km/sup 2/ flood plain. The peats here occurred in several layers (each <1-1/2 meters thick), interfingering with river flood plain sediments. These peats have the highest calorific values (avg. 8000 BTUs/lb., dry), fixed carbon (avg. 30%), and ash (avg. 22%) and have an average pH of 5.4 and a bulk density of 0.20 g/cc. These results represent only the first part of a long-term, extensive survey of Costa Rica's peat resources. However, they suggest that large, economically-significant peat deposits may be present in this country. 5 refs., 8 figs., 4 tabs.« less

Peat resources of Maine. Volume 2. Penobscot County

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cameron, C.C.; Mullen, M.K.; Lepage, C.A.

1984-01-01

In July 1979, the Maine Office of Energy Resources, in conjunction with the Maine Geological Survey, began the Maine Peat Resource Evaluation Program. The Program, which was funded by the US Department of Energy (DOE), was undertaken to determine the amount and location of fuel-grade peat in Maine. Two hundred thirty-three areas containing peat deposits were evaluated under the Program. A total of 47 deposits covering 21,666 acres and containing 40,923,000 short tons (dry weight) of peat in Penobscot County have been evaluated under the Maine Peat Resource Evaluation Program. These deposits range in size from 35 to 3301 acresmore » and in estimated resources from 45,000 to 6,994,000 short tons. Maps of individual deposits showing the distribution and depth of peat, core sites, and the surficial geology of the area adjacent to the deposits are shown in Figures 4 to 46. Cores showing the vertical distribution of peat and sediment as well as sample locations, and the results of laboratory analyses are also included. 22 references, 46 figures, 3 tables.« less

3D modelling of mechanical peat properties in the Holocene coastal-deltaic sequence of the Netherlands

NASA Astrophysics Data System (ADS)

Koster, Kay; Stouthamer, Esther; Cohen, Kim; Stafleu, Jan; Busschers, Freek; Middelkoop, Hans

2016-04-01

Peat is abundantly present within the Holocene coastal-deltaic sequence of the Netherlands, where it is alternating with clastic fluvial, estuarine and lagoonal deposits. The areas that are rich in peat are vulnerable to land subsidence, resulting from consolidation and oxidation, due to loading by overlying deposits, infrastructure and buildings, as well as excessive artificial drainage. The physical properties of the peat are very heterogeneous, with variable clastic admixture up to 80% of its mass and rapid decrease in porosity with increasing effective stress. Mapping the spatial distribution of the peat properties is essential for identifying areas most susceptible to future land subsidence, as mineral content determines volume loss by oxidation, and porosity influences the rate of consolidation. Here we present the outline of a study focusing on mapping mechanical peat properties in relation to density and amount of admixed clastic constituents of Holocene peat layers (in 3D). In this study we use a staged approach: 1) Identifying soil mechanical properties in two large datasets that are managed by Utrecht University and the Geological Survey. 2) Determining relations between these properties and palaeogeographical development of the area by evaluating these properties against known geological concepts such as distance to clastic source (river, estuary etc.). 3) Implementing the obtained relations in GeoTOP, which is a 3D geological subsurface model of the Netherlands developed by the Geological Survey. The model will be used, among others, to assess the susceptibility of different areas to peat related land subsidence and load bearing capacity of the subsurface. So far, our analysis has focused stage 1, by establishing empirical relations between mechanical peat properties in ~70 paired (piezometer) cone penetration tests and continuously cored boreholes with LOI measurements. Results show strong correlations between net cone resistance (qn), excess pore water (u1-u0), and total vertical stress (σvo), suggesting that the overburden strongly controls the vertical differential susceptibility of peat layers to consolidation.

Organic Geochemical Characteristics and Depositional Environment of Aǧaçbaşi Plateau Peat, Köprübaşi/Trabzon, NE Turkey

NASA Astrophysics Data System (ADS)

Hoş Çebi, Fatma; Korkmaz, Sadettin

2013-04-01

Young peat deposits crop out in the southern part of the Aǧaçbaşı region of Trabzon city, Northern Turkey. In this study, chemical, organic geochemical, petrographic and palynological features of the peat occurrences are investigated and results obtained evaluated. According to palynological investigations, it is determined that peats were occured in terrestrial or lacustrine environments, which is containing average of 80% woody, 15% herbaceous and 5% amorphous organic matter. Age of peats has been determined as Miocene or younger, by the palynological age determinations. It is understood from the obtained SCI (Sport Color Index) analysis results that constituting organic material of peat is immature. Total organic carbon content of the peat is average 41.69% by pyrolysis analysis. HI values were calculated as average 315.46 mgHC/gTOC, which is very high for the coal occurrences. The high OI values (avg. 134 mgCO2/gTOC) show that the environments of peat deposits were oxic or suboxic. TAR (Terrigenous/Aquatic Ratio) and CPI (Carbon Preference Index) index value, is found to be 2.4 and 3.4 respectively. These values that resulted from dominance of high-numbered n-alkanes, indicate terrestrial organic matter input. According to the m/z 191 and m/z 217 mass peaks of GC chromatogram data which is obtained by biomarker analysis, sterane/hopane ratio suggests algal organic matter. Moreover, the lack of C34 and C35 homohopans show that organic matter deposited under oxic or suboxic conditions. Moretane/hopane, Tm/Ts and Tm/C30 hopane ratios were calculated in order of 0.15, 3.25 and 0.33, respectively. These values imply acidic and oxic conditions during the formation of peat. Due to the absence of 17α(H)-28.30-bisnorhopan in the m/z 191 chromatograms, it is concluded that Aǧaçbaşı plateau peat might be deposited in a terrestrial or lacustrine environments under oxic or suboxic conditions. Dominant sterane content of C29 suggests terrestrial organic matter input. In the sterane triangle diagram, the extract of the peat sample was plotted in the area of high plant and brown and green alga inputs. Also C30 sterane, which is implication of marine environment, has not been recorded on chromatogram. 22S/(22S+22R) homohopan index, Ts/(Ts+Tm), moretan/hopane, 20S/(20S+20R) sterane and ββ/(ββ+αα) sterane ratios suggest immature level of the organic matter. Key Words: peat, biomarker, sterane, terpane

Methane and carbon dioxide exchange in a post-extraction, unrestored peatland in Eastern Quebec, Canada

NASA Astrophysics Data System (ADS)

Rankin, Tracy; Strachan, Ian; Strack, Maria

2017-04-01

Peatlands, in their pristine state, are important long-term sinks of carbon. The extraction of peat for agricultural purposes or for biofuel leads to a shift in the carbon dynamics. Changes in environmental conditions post extraction may also allow for invasive species to establish and spread across the peatland. Many studies have shown the benefits and advantages of various restoration management practices, but few studies have explored the carbon exchange from unrestored peatlands. Our study reports the methane (CH4) and carbon dioxide (CO2) fluxes from a post-extraction, unrestored peatland in Eastern Québec at both the plant community scale using static chambers, and at the ecosystem scale using an eddy covariance flux tower, over two complete years. Extraction of the Saint-Alexandre-de-Kamouraska peatland (SAK) started in the early 1970's and was halted in 1999. No restoration efforts have been implemented and the remnant ditches remain unblocked. The site consists of sparse patches of Eriophorum and a vast area of bare peat. Consequently, SAK is an overall source of carbon to the atmosphere, releasing an annual total of 153 g C m-2 and 241 g C m-2 in CO2 emissions for 2014 and 2015, respectively, and an average annual total of 1 g C m-2yr-1 in CH4 emissions. Phragmites and Typha, both invasive species, have established themselves in the ditches and are sources of methane; partly explaining the increased emissions in carbon fluxes to the atmosphere post extraction. Results from this study will help managers assess the importance of post-extraction peatland restoration, by comparing the differences in CO2 and CH4 exchange between restored and unrestored peatlands.

The effect of Sphagnum farming on the greenhouse gas balance of donor and propagation areas, irrigation polders and commercial cultivation sites

NASA Astrophysics Data System (ADS)

Oestmann, Jan; Tiemeyer, Bärbel

2017-04-01

Drainage of peatlands for agriculture, forestry and peat extraction turned these landscapes into hotspots of greenhouse gas emissions. Climate protection now fosters rewetting projects to restore the natural peatland function as a sink of atmospheric carbon. One possible way to combine ecological and economical goals is Sphagnum farming, i.e. the cultivation of Sphagnum mosses as high-quality substrates for horticulture. This project scientifically evaluates the attempt of commercial Sphagnum farming on former peat extraction sites in north-western Germany. The exchange of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) of the whole peatland-based production chain comprising a donor mire, a propagation area, an irrigation polder and a cultivation site will be determined in a high temporal resolution for two years using manual chambers. This will allow evaluating the greenhouse gas balance of Sphagnum farming sites in comparison to near-natural sites and the potential of Sphagnum farming for restoring drained peatlands to sinks of atmospheric carbon. The influence of different irrigation techniques will also be tested. Additionally, selected plots will be equipped with open top chambers in order to examine the greenhouse gas exchange under potential future climate change conditions. Finally, a 13C pulse labeling experiment will make it possible to trace the newly sequestered CO2 in biomass, soil, respiration and dissolved organic carbon.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Amman, G.D.; Ryan, K.C.

The bark beetle antiaggregative pheromones, verbenone and ipsdienol, were tested in protecting heat-injured lodgepole pine (Pinus contorta Dougl. ex Loud.) from mountain pine beetle (Dendroctonus ponderosae) infestation in the Sawtooth National Recreation Area in central Idaho. Peat moss was placed around 70 percent of the basal circumference of lodgepole pines. When the peat moss was ignited, it simulated the smoldering of natural duff, generating temperatures that killed the cambium. The four treatments tested were uninjured tree, heat-injured tree, heat-injured tree treated with verbenone, and heat-injured tree treated with verbenone plus ipsdienol. Treatments were replicated 20 times. Mountain pine beetles weremore » attracted into treatment blocks by placing mountain pine beetle tree baits on metal posts 3 to 5 meters from treated trees. Fisher's Extract Test showed that treatment and beetle infestation were not independent (P < 0.015). Check treatments contained more unattacked and mass-attacked trees, whereas pheromone treatments contained more unsuccessfully attacked trees.« less

Analysis of Absorption Spectra of Polycyclic Aromatic Hydrocarbons in Gaseous- and Particle- Phase Emissions from Peat Fuel Combustion Under Controlled Conditions

NASA Astrophysics Data System (ADS)

Connolly, J. I.; Samburova, V.; Moosmüller, H.; Khlystov, A.

2015-12-01

Biomass and fossil fuel burning processes emit important organic pollutants called polycyclic aromatic hydrocarbons (PAHs) into the atmosphere. Smoldering combustion of peat is one of the largest contributors (up to 70%) of carbonaceous species and, therefore, it may be one of the main sources of these PAHs. PAHs can be detrimental to health, they are known to be potent mutagens and suspected carcinogens. They may also contribute to solar light absorption as the particles absorb in the blue and near ultraviolet (UV) region of the solar spectrum ("brown carbon" species). There is very little knowledge and large ambiguity regarding the contribution of PAHs to optical properties of organic carbon (OC) emitted from smoldering biomass combustion. This study focuses on quantifying and analyzing PAHs emitted from peat smoldering combustion to gain more knowledge on their optical properties. Five peat fuels collected in different regions of the world (Russia, USA) were burned under controlled conditions (e.g., relative humidity, combustion efficiency, fuel-moisture content) at the Desert Research Institute Biomass Burning facility (Reno, NV, USA). Combustion aerosols collected on TIGF filters followed by XAD resin cartridges were extracted and analyzed for gas-phase (semi-volatile) and particle-phase PAHs. Filter and XAD samples were extracted separately with dichloromethane followed by acetone using Accelerated Solvent Extractor (ACE 300, Dionex). To determine absorption properties, absorption spectra of extracts and standard PAHs were recorded between 190 and 900 nm with a UV/VIS spectrophotometer (PerkinElmer, Lambda 650). This poster will discuss the potential contribution of PAHs to brown carbon emitted from peat combustion and give a brief comparison with absorption spectra from biomass burning aerosols.

Bacterial and Fungal Communities in a Degraded Ombrotrophic Peatland Undergoing Natural and Managed Re-Vegetation

PubMed Central

Elliott, David R.; Caporn, Simon J. M.; Nwaishi, Felix; Nilsson, R. Henrik; Sen, Robin

2015-01-01

The UK hosts 15–19% of global upland ombrotrophic (rain fed) peatlands that are estimated to store 3.2 billion tonnes of carbon and represent a critical upland habitat with regard to biodiversity and ecosystem services provision. Net production is dependent on an imbalance between growth of peat-forming Sphagnum mosses and microbial decomposition by microorganisms that are limited by cold, acidic, and anaerobic conditions. In the Southern Pennines, land-use change, drainage, and over 200 years of anthropogenic N and heavy metal deposition have contributed to severe peatland degradation manifested as a loss of vegetation leaving bare peat susceptible to erosion and deep gullying. A restoration programme designed to regain peat hydrology, stability and functionality has involved re-vegetation through nurse grass, dwarf shrub and Sphagnum re-introduction. Our aim was to characterise bacterial and fungal communities, via high-throughput rRNA gene sequencing, in the surface acrotelm/mesotelm of degraded bare peat, long-term stable vegetated peat, and natural and managed restorations. Compared to long-term vegetated areas the bare peat microbiome had significantly higher levels of oligotrophic marker phyla (Acidobacteria, Verrucomicrobia, TM6) and lower Bacteroidetes and Actinobacteria, together with much higher ligninolytic Basidiomycota. Fewer distinct microbial sequences and significantly fewer cultivable microbes were detected in bare peat compared to other areas. Microbial community structure was linked to restoration activity and correlated with soil edaphic variables (e.g. moisture and heavy metals). Although rapid community changes were evident following restoration activity, restored bare peat did not approach a similar microbial community structure to non-eroded areas even after 25 years, which may be related to the stabilisation of historic deposited heavy metals pollution in long-term stable areas. These primary findings are discussed in relation to bare peat oligotrophy, re-vegetation recalcitrance, rhizosphere-microbe-soil interactions, C, N and P cycling, trajectory of restoration, and ecosystem service implications for peatland restoration. PMID:25969988

Bacterial and fungal communities in a degraded ombrotrophic peatland undergoing natural and managed re-vegetation.

PubMed

Elliott, David R; Caporn, Simon J M; Nwaishi, Felix; Nilsson, R Henrik; Sen, Robin

2015-01-01

The UK hosts 15-19% of global upland ombrotrophic (rain fed) peatlands that are estimated to store 3.2 billion tonnes of carbon and represent a critical upland habitat with regard to biodiversity and ecosystem services provision. Net production is dependent on an imbalance between growth of peat-forming Sphagnum mosses and microbial decomposition by microorganisms that are limited by cold, acidic, and anaerobic conditions. In the Southern Pennines, land-use change, drainage, and over 200 years of anthropogenic N and heavy metal deposition have contributed to severe peatland degradation manifested as a loss of vegetation leaving bare peat susceptible to erosion and deep gullying. A restoration programme designed to regain peat hydrology, stability and functionality has involved re-vegetation through nurse grass, dwarf shrub and Sphagnum re-introduction. Our aim was to characterise bacterial and fungal communities, via high-throughput rRNA gene sequencing, in the surface acrotelm/mesotelm of degraded bare peat, long-term stable vegetated peat, and natural and managed restorations. Compared to long-term vegetated areas the bare peat microbiome had significantly higher levels of oligotrophic marker phyla (Acidobacteria, Verrucomicrobia, TM6) and lower Bacteroidetes and Actinobacteria, together with much higher ligninolytic Basidiomycota. Fewer distinct microbial sequences and significantly fewer cultivable microbes were detected in bare peat compared to other areas. Microbial community structure was linked to restoration activity and correlated with soil edaphic variables (e.g. moisture and heavy metals). Although rapid community changes were evident following restoration activity, restored bare peat did not approach a similar microbial community structure to non-eroded areas even after 25 years, which may be related to the stabilisation of historic deposited heavy metals pollution in long-term stable areas. These primary findings are discussed in relation to bare peat oligotrophy, re-vegetation recalcitrance, rhizosphere-microbe-soil interactions, C, N and P cycling, trajectory of restoration, and ecosystem service implications for peatland restoration.

Water relations in cutover peatlands

NASA Astrophysics Data System (ADS)

Price, Jonathan S.; Ketcheson, Scott J.

Sphagnum mosses, the dominant peat-forming plant in many northern peatlands, generally do not regenerate spontaneously in mined peatlands because water transfer between the cutover peat and incipient moss diaspores cannot overcome the capillary barrier effect between the two hydraulically distinct layers. Artificial drainage networks established throughout peatlands, coupled with the removal of the acrotelm during the peat extraction process, drastically alter the natural system function through the exposure of more decomposed catotelm peat and increased compression, oxidation, and shrinkage, subsequently decreasing average pore diameter and enhancing this capillary barrier effect. Water table (WT) fluctuations, constrained within the reduced specific yield of the altered catotelm, exhibit increased variability and rapid decline. The increased effective stress caused by a declining WT can result in seasonal surface subsidence of 8 to 10 cm, thereby reducing saturated hydraulic conductivity by three orders of magnitude. Restoration efforts aim to alter the disturbed hydrological regime, creating conditions more favorable for the recolonization of Sphagnum mosses and the ultimate reestablishment of an upper acrotelm layer. Due to the large areal coverage and high organic carbon content, the response of peatlands to disturbances caused by resource extraction, and their return to functioning ecosystems, must be thoroughly addressed. This paper integrates both published and unpublished work to facilitate an overview of our understanding of the hydrological impact of peat cutting and its implications for restoration.

Landscape-scale changes in forest canopy structure across a partially logged tropical peat swamp

NASA Astrophysics Data System (ADS)

Wedeux, B. M. M.; Coomes, D. A.

2015-07-01

Forest canopy structure is strongly influenced by environmental factors and disturbance, and in turn influences key ecosystem processes including productivity, evapotranspiration and habitat availability. In tropical forests increasingly modified by human activities, the interplaying effects of environmental factors and disturbance legacies on forest canopy structure across landscapes are practically unexplored. We used high-fidelity airborne laser scanning (ALS) data to measure the canopy of old-growth and selectively logged peat swamp forest across a peat dome in Central Kalimantan, Indonesia, and quantified how canopy structure metrics varied with peat depth and under logging. Several million canopy gaps in different height cross-sections of the canopy were measured in 100 plots of 1 km2 spanning the peat dome, allowing us to describe canopy structure with seven metrics. Old-growth forest became shorter and had simpler vertical canopy profiles on deeper peat, consistently with previous work linking deep peat to stunted tree growth. Gap Size Frequency Distributions (GSFDs) indicated fewer and smaller canopy gaps on the deeper peat (i.e. the scaling exponent of pareto functions increased from 1.76 to 3.76 with peat depth). Areas subjected to concessionary logging until 2000, and informal logging since then, had the same canopy top height as old-growth forest, indicating the persistence of some large trees, but mean canopy height was significantly reduced; the total area of canopy gaps increased and the GSFD scaling exponent was reduced. Logging effects were most evident on the deepest peat, where nutrient depletion and waterlogged conditions restrain tree growth and recovery. A tight relationship exists between canopy structure and the peat deph gradient within the old-growth tropical peat swamp. This relationship breaks down after selective logging, with canopy structural recovery being modulated by environmental conditions.

Geophysical survey for groundwater potential investigation in peat land area, Riau, Indonesia

NASA Astrophysics Data System (ADS)

Islami, N.; Irianti, M.; Azhar; Nor, M.; Fakhrudin

2018-04-01

Tropical forests, especially peat lands, are particularly vulnerable to forest fires. Fires are the most common disasters in peat lands in the dry season, especially in Riau Province, Indonesia. In the process of extinguishing the peat fire, several substantial problems arise to stop peat fires during this period. This study aims to determine the possibility of using ground water as a source of water to anticipate the early mitigation of peat land fires disaster. The geoelectrical resistivity surveys were used to predict the subsurface geological data including peat thickness and depth of aquifers. The geometry of peat lands was determined using geostatistics based on geoelectrical resistivity interpretation data. Peat Land thickness varies up to 4 m in the north and is thinner to the south. A shallower and deeper aquifer is available at a depth of 13 m to 18 m and 70 m to 90 m respectively. In general, the potential of groundwater in the shallow aquifer is predicted to be sufficient for peat land watering anytime.

Does peatland restoration make a difference to the millennial scale carbon balance?

NASA Astrophysics Data System (ADS)

Quillet, Anne; Roulet, Nigel; Wu, Jianghua

2017-04-01

Millennial peatland carbon balance is of crucial importance to assess the past and future forcing of peatlands carbon sequestration on climate. However drainage and exploitation of peatlands over the last and current centuries greatly affect the carbon balance of 25% of the global peatlands (Parish et al. 2008). Moreover, the impact of drainage is likely to remain for unforeseeable time, modifying the hydrology and the ecology of peatlands. The aim of this study is to assess the influence on the long-term carbon balance of restoration practices over abandonment on vacuum-extracted peatlands. We modified the Holocene Peat Model (Frolking et al. 2010) to simulate peat extraction as well as different post-extraction management strategies: abandonment, drainage blocking and restoration. Simulation results enable the comparison of the response of the system to different management strategies. The carbon balance is estimated for the millennia following extraction for different management strategies and different climate conditions. The difference between restoration practices and abandonment allows the assessment of the net carbon gain associated with restoration. Although it is expected that successful restoration practices are beneficial to the carbon budget of the ecosystem, it will take millennia to restore what has been extracted. In cases where the site is left abandoned, it is estimated that peat would degrade within centuries. The management strategies and the duration of the period of latency between extraction and restoration are key factors controlling the magnitude of the future carbon loss or gain of a peatland.

Emissions of volatile organic compounds and particulate matter from small-scale peat fire

EPA Science Inventory

Air pollution emitted from peat fires can negatively impact regional air quality, visibility, climate, and human health. Peat fires can smolder over long periods of time and, therefore, can release significantly greater amounts of carbon into the atmosphere per unit area compared...

Emissions of volatile organic compounds and particulate matter from small-scale peat fires

EPA Science Inventory

Air pollution emitted from peat fires can negatively impact regional air quality, visibility, climate, and human health. Peat fires can smolder over long periods of time and, therefore, can release significantly greater amounts of carbon into the atmosphere per unit area compared...

Landscape-scale changes in forest canopy structure across a partially logged tropical peat swamp

NASA Astrophysics Data System (ADS)

Wedeux, B. M. M.; Coomes, D. A.

2015-11-01

Forest canopy structure is strongly influenced by environmental factors and disturbance, and in turn influences key ecosystem processes including productivity, evapotranspiration and habitat availability. In tropical forests increasingly modified by human activities, the interplay between environmental factors and disturbance legacies on forest canopy structure across landscapes is practically unexplored. We used airborne laser scanning (ALS) data to measure the canopy of old-growth and selectively logged peat swamp forest across a peat dome in Central Kalimantan, Indonesia, and quantified how canopy structure metrics varied with peat depth and under logging. Several million canopy gaps in different height cross-sections of the canopy were measured in 100 plots of 1 km2 spanning the peat dome, allowing us to describe canopy structure with seven metrics. Old-growth forest became shorter and had simpler vertical canopy profiles on deeper peat, consistent with previous work linking deep peat to stunted tree growth. Gap size frequency distributions (GSFDs) indicated fewer and smaller canopy gaps on the deeper peat (i.e. the scaling exponent of Pareto functions increased from 1.76 to 3.76 with peat depth). Areas subjected to concessionary logging until 2000, and illegal logging since then, had the same canopy top height as old-growth forest, indicating the persistence of some large trees, but mean canopy height was significantly reduced. With logging, the total area of canopy gaps increased and the GSFD scaling exponent was reduced. Logging effects were most evident on the deepest peat, where nutrient depletion and waterlogged conditions restrain tree growth and recovery. A tight relationship exists between canopy structure and peat depth gradient within the old-growth tropical peat swamp forest. This relationship breaks down after selective logging, with canopy structural recovery, as observed by ALS, modulated by environmental conditions. These findings improve our understanding of tropical peat swamp ecology and provide important insights for managers aiming to restore degraded forests.

Ancient peat and apple extracts supplementation may improve strength and power adaptations in resistance trained men.

PubMed

Joy, Jordan M; Vogel, Roxanne M; Moon, Jordan R; Falcone, Paul H; Mosman, Matt M; Pietrzkowski, Zbigniew; Reyes, Tania; Kim, Michael P

2016-07-18

Increased cellular ATP levels have the potential to enhance athletic performance. A proprietary blend of ancient peat and apple extracts has been supposed to increase ATP production. Therefore, the purpose of this investigation was to determine the effects of this supplement on athletic performance when used during 12 weeks of supervised, periodized resistance training. Twenty-five healthy, resistance-trained, male subjects completed this study. Subjects supplemented once daily with either 1 serving (150 mg) of a proprietary blend of ancient peat and apple extract (TRT) or an equal-volume, visually-identical placebo (PLA) daily. Supervised resistance training consisted of 8 weeks of daily undulating periodized training followed by a 2 week overreach and a 2 week taper phase. Strength was determined using 1-repetition-maximum (1RM) testing in the barbell back squat, bench press (BP), and deadlift exercises. Peak power and peak velocity were determined during BP at 30 % 1RM and vertical jump tests as well as a 30s Wingate test, which also provided relative power (watt:mass) A group x time interaction was present for squat 1RM, deadlift 1RM, and vertical jump peak power and peak velocity. Squat and deadlift 1RM increased in TRT versus PLA from pre to post. Vertical jump peak velocity increased in TRT versus PLA from pre to week 10 as did vertical jump peak power, which also increased from pre to post. Wingate peak power and watt:mass tended to favor TRT. Supplementing with ancient peat and apple extract while participating in periodized resistance training may enhance performance adaptations. ClinicalTrials.gov registration ID: NCT02819219 , retrospectively registered on 6/29/2016.

Characterisation of VOC, SVOC, and PM emissions from peat burnt in laboratory simulations

EPA Science Inventory

Peat, or organic soil, is a vast store of organic carbon, widely distributed from polar temperate to equatorial regions. Drainage for agriculture and drought are drying vast areas of peat, exposing it to increasing fire risk, which may be exacerbated by climate change. This has ...

A Few Issues on the Peat Research in the Altai Mountains

NASA Astrophysics Data System (ADS)

Inisheva, Lydia I.; Larina, Galina; Shurova, Maya

2010-05-01

At the present time we carry out complex research of marsh ecosystems in various areas of Gorny Altai to reveal the perspective deposits of peat in the Altai Mountains with the purpose of its use in the medical and recreational spheres. The peat deposits of the Northeastern Altai, Central Altai, and Southeastern Altai are surveyed; the selective chemical analysis of peat and marsh waters is carried out. The group structure of organic substance of various samples of peat is investigated by the method of Institutes of Peat. The toxic metals of Cd, Pb, Hg, Cu, Zn, and As were defined by the method of stripping voltammetry. The region of the Altai Mountains is characterized by the contrastive distribution of some heavy metals and arsenic in a soil cover. This is caused by a variety of petrography and granulometry of soil forming material, and also by a landscape and geochemical situation in the system of vertical zoning. The sources of natural accumulation of heavy metals in the ground might be the deposits of polymetals. In this connection the content of the specified toxic elements in the peat under research has been identified. The peat of the Turochak deposit is characterized by a significant ash content - up to 41,9%; the increased ash content is typical of the Kutyush deposit: from 6,1% up to 19, %. The peat of the Northeastern Altai is referred to non-bitumunous: the content of bitumen makes up less than 5%. In comparison with the European peat the peat under study of the transitive and lowland type is characterized by the significant content of easy hydrolysable substances in the amount of 24,8-41,1%. The amount of the non-hydrolysable rest makes up around 4,3 - 7,4 %. The total content of fulvic acids is less than the content of humic acids by 2,9 - 5,8 times. The high content of humic acids which can reach up to 58 % is characteristic of certain deposits. Humic acids extracted from the peat are characterized, as a rule, by similar IR-spectra. The distinctions are shown in an unequal intensity of characteristic absorption bands, in their spreading and some shifts. It is revealed that humic acids of peat with the increase in a degree of decomposition are exposed to transformation; therefore the increase in their structure of functional groups is observed. As a result of the research which was carried out the following elements among heavy metals in the lowland peat of the Altai Mountains are revealed: Cd (2,7 - 30)> Hg (0,67)> Zn (0,22) ~Pb (0,21)> Cu (0,13)> As (0,03). The degree of mobility of chemical elements in the peat varies within the limits of 1,3 - 36%. According to the degree of their mobility these elements form the following line: Zn (36 %)> Pb (18,1 %)> Cd (9,6 %)> Cu (1,3 %). The content and the character of distribution of the heavy metals under study and arsenic in the peat of the Altai Mountains have their unique features in comparison with the same valley analogues. The mountain peat of the Central Altai contains much less Hg than the West Siberian one: 0,078 mg/g and 0,69 mg/g accordingly. Cd represents itself as the concentrator in the lowland peat of the Northeastern and Central Altai, its content is actually the same and makes up approximately 0,3 mg/kg. The lowland Altai and West Siberian peat has the same amount of Pb: 4-5 mg/kg; they have smaller amounts of Zn and Cu in comparison with the European and West Siberian peat. The revealed features of distribution of some toxic metals are the display of specificity of peat genesis in the conditions of a mountain relief. The complex of the data received by us allows to consider the peat of the Altai Mountains as a non-polluting raw source concerning the amount of some natural toxic substances. The possible perspective directions of practical application of the mountain peat can be medicine, veterinary science, and agriculture.

Peat soil composition as indicator of plants growth environment

NASA Astrophysics Data System (ADS)

Noormets, M.; Tonutare, T.; Kauer, K.; Szajdak, L.; Kolli, R.

2009-04-01

Exhausted milled peat areas have been left behind as a result of decades-lasting intensive peat production in Estonia and Europe. According to different data there in Estonia is 10 000 - 15 000 ha of exhausted milled peat areas that should be vegetated. Restoration using Sphagnum species is most advantageous, as it creates ecological conditions closest to the natural succession towards a natural bog area. It is also thought that the large scale translocation of vegetation from intact bogs, as used in some Canadian restoration trials, is not applicable in most of European sites due to limited availability of suitable donor areas. Another possibility to reduce the CO2 emission in these areas is their use for cultivation of species that requires minimum agrotechnical measures exploitation. It is found by experiments that it is possible to establish on Vaccinium species for revegetation of exhausted milled peat areas. Several physiological activity of the plant is regulated by the number of phytohormones. These substances in low quantities move within the plant from a site of production to a site of action. Phytohormone, indole-3-acetic acid (IAA) is formed in soils from tryptophane by enzymatic conversion. This compound seems to play an important function in nature as result to its influence in regulation of plant growth and development. A principal feature of IAA is its ability to affect growth, development and health of plants. This compound activates root morphology and metabolic changes in the host plant. The physiological impact of this substance is involved in cell elongation, apical dominance, root initiation, parthenocarpy, abscission, callus formation and the respiration. The investigation areas are located in the county of Tartu (58˚ 22' N, 26˚ 43' E), in the southern part of Estonia. The soil of the experimental fields belongs according to the WRB soil classification, to the soils subgroups of Fibri-Dystric Histosols. The investigation areas were chosen by following criteria: (1) plantcover age; (2) cultivated plant species; (3) utilized agrotechnology; (4) comparisons between different factors were created by using natural growth areas of Vaccinaceae (natural bog area, Vaccinaceae growth area on mineral soil). For the investigation is important to choose areas with different age of plant covers, because according to plants age the surface of exhausted peat land will be covered in relation to the width of plants. The purpose of current article is to investigate the biological and chemical parameters co-influences in peat soil. Thus, the major interest is on the plant growth hormone indole-3-acetic acid distribution and dynamics in peat soil and dependence of plant cover, also its influence to the plants growth. Moreover, its contribution to yield and new growth area invasion will be discussed.

Factors affecting re-vegetation dynamics of experimentally restored extracted peatland in Estonia.

PubMed

Karofeld, Edgar; Müür, Mari; Vellak, Kai

2016-07-01

Increasing human activity continues to threaten peatlands, and as the area of natural mires declines, our obligation is to restore their ecosystem functions. Several restoration strategies have been developed for restoration of extracted peatlands, including "The moss layer transfer method", which was initiated on the Tässi extracted peatland in central Estonia in May 2012. Three-year study shows that despite the fluctuating water table, rainfall events can compensate for the insufficient moisture for mosses. Total plant cover on the restoration area attained 70 %, of which ~60 % is comprised of target species-Sphagnum mosses. From restoration treatments, spreading of plant fragments had a significant positive effect on the cover of bryophyte and vascular plants. Higher water table combined with higher plant fragments spreading density and stripping of oxidised peat layer affected positively the cover of targeted Sphagnum species. The species composition in the restoration area became similar to that in the donor site in a natural bog. Based on results, it was concluded that the method approved for restoration in North America gives good results also in the restoration of extracted peatland towards re-establishment of bog vegetation under northern European conditions.

Finnish bioenergy research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malinen, H.

1993-12-31

Finland is one of the leading countries in the use of biofuels. The share of wood derived fuels of the total primary energy requirement was about 14% (ca. 4 million toe) and peat about 5% (1.4 million toe). The possibilities for increasing the use of biofuels in Finland are significant. There is theoretically about 10 million m{sup 3}/a (about 2 million toe/a) of harvestable wood. Areas suitable for fuel peat production (0.5 million ha) could produce ca. 420 million toe of peat. At present rates of use, the peat reserves are adequate for centuries. During the next few years 0.5--1more » million hectares of fields withdrawn from farming could be used for biofuel production. The production potential of this field area is estimated to be about 0.2--0.5 million toe. In addition, the use of wastes in energy production could be increased. The aim of the new Bioenergy Research Programme is to increase the use of economically profitable and environmentally sound bioenergy by improving the competitiveness of present peat and wood fuels. New economically competitive biofuels, new equipment and methods for production, handling and use of biofuels will also be developed. The main research areas are production of wood fuels, peat production, use of bioenergy and conversion of biomass.« less

Effectiveness of submerged drains in reducing subsidence of peat soils in agricultural use, and their effects on water management and nutrient loading of surface water: modelling of a case study in the western peat soil area of The Netherlands

NASA Astrophysics Data System (ADS)

Hendriks, Rob F. A.; van den Akker, Jan J. A.

2017-04-01

Effectiveness of submerged drains in reducing subsidence of peat soils in agricultural use, and their effects on water management and nutrient loading of surface water: modelling of a case study in the western peat soil area of The Netherlands In the Netherlands, about 8% of the area is covered by peat soils. Most of these soils are in use for dairy farming and, consequently, are drained. Drainage causes decomposition of peat by oxidation and accordingly leads to surface subsidence and greenhouse gas emission. Submerged drains that enhance submerged infiltration of water from ditches during the dry and warm summer half year were, and are still, studied in The Netherlands as a promising tool for reducing peat decomposition by raising groundwater levels. For this purpose, several pilot field studies in the Western part of the Dutch peat area were conducted. Besides the effectiveness of submerged drains in reducing peat decomposition and subsidence by raising groundwater tables, some other relevant or expected effects of these drains were studied. Most important of these are water management and loading of surface water with nutrients nitrogen, phosphorus and sulphate. Because most of these parameters are not easy to assess and all of them are strongly depending on the meteorological conditions during the field studies some of these studies were modelled. The SWAP model was used for evaluating the hydrological results on groundwater table and water discharge and recharge. Effects of submerged drains were assessed by comparing the results of fields with and without drains. An empirical relation between deepest groundwater table and subsidence was used to convert effects on groundwater table to effects on subsidence. With the SWAP-ANIMO model nutrient loading of surface water was modelled on the basis of field results on nutrient concentrations . Calibrated models were used to assess effects in the present situation, as thirty-year averages, under extreme weather conditions and for two extreme climate scenarios of the Royal Netherlands Meteorological Institute. In this study the model results of one of the pilot studies are presented. The case study 'de Krimpenerwaard' is situated in the peat area in the "Green Heart" between the major cities of Amsterdam, The Hague, Rotterdam and Utrecht. Model results show a halving of soil subsidence, a strong increase of water recharge but a lower increase of water discharge, and generally small to moderate effects on nutrient loading , all depending (strongly) on meteorological conditions.

An expert system model for mapping tropical wetlands and peatlands reveals South America as the largest contributor.

PubMed

Gumbricht, Thomas; Roman-Cuesta, Rosa Maria; Verchot, Louis; Herold, Martin; Wittmann, Florian; Householder, Ethan; Herold, Nadine; Murdiyarso, Daniel

2017-09-01

Wetlands are important providers of ecosystem services and key regulators of climate change. They positively contribute to global warming through their greenhouse gas emissions, and negatively through the accumulation of organic material in histosols, particularly in peatlands. Our understanding of wetlands' services is currently constrained by limited knowledge on their distribution, extent, volume, interannual flood variability and disturbance levels. We present an expert system approach to estimate wetland and peatland areas, depths and volumes, which relies on three biophysical indices related to wetland and peat formation: (1) long-term water supply exceeding atmospheric water demand; (2) annually or seasonally water-logged soils; and (3) a geomorphological position where water is supplied and retained. Tropical and subtropical wetlands estimates reach 4.7 million km 2 (Mkm 2 ). In line with current understanding, the American continent is the major contributor (45%), and Brazil, with its Amazonian interfluvial region, contains the largest tropical wetland area (800,720 km 2 ). Our model suggests, however, unprecedented extents and volumes of peatland in the tropics (1.7 Mkm 2 and 7,268 (6,076-7,368) km 3 ), which more than threefold current estimates. Unlike current understanding, our estimates suggest that South America and not Asia contributes the most to tropical peatland area and volume (ca. 44% for both) partly related to some yet unaccounted extended deep deposits but mainly to extended but shallow peat in the Amazon Basin. Brazil leads the peatland area and volume contribution. Asia hosts 38% of both tropical peat area and volume with Indonesia as the main regional contributor and still the holder of the deepest and most extended peat areas in the tropics. Africa hosts more peat than previously reported but climatic and topographic contexts leave it as the least peat-forming continent. Our results suggest large biases in our current understanding of the distribution, area and volumes of tropical peat and their continental contributions. © 2017 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

Towards a conceptual model of hydrological change on an abandoned cutover bog, Quebec

NASA Astrophysics Data System (ADS)

van Seters, Tim E.; Price, Jonathan S.

2002-07-01

Cutover bogs do not return to functional peatland ecosystems after abandonment because re-establishment of peat-forming mosses is poor. This paper presents a conceptual model of bog disturbance caused by peat harvesting (1942-1972), and the hydrological evolution that occurred after abandonment (1973-1998). Two adjacent bogs of similar size and origin, one harvested and the other essentially undisturbed, provide the basis for understanding what changes occurred. The model is based on historical trends evident from previous surveys of land-use, bog ecology and resource mapping; and from recent hydrological and ecological data that characterize the current condition. Water balance data and historical information suggest that runoff increased and evapotranspiration decreased following drainage, but tended towards pre-disturbance levels following abandonment, as vegetation recolonized the surface and drainage became less efficient over time. Dewatering of soil pores after drainage caused shrinkage and oxidation of the peat and surface subsidence of approximately 80 cm over 57 years. Comparisons with a nearby natural bog suggest that bulk density in the upper 50 cm of cutover peat increased from 0·07 to 0·13 g cm-3, specific yield declined from 0·14 to 0·07, water table fluctuations were 67% greater, and mean saturated hydraulic conductivity declined from 4·1 × 10-5 to 1·3 × 10-5 cm s-1. More than 25 years after abandonment, Sphagnum mosses were distributed over broad areas but covered less than 15% of the surface. Areas with good Sphagnum regeneration (>10% cover) were strongly correlated with high water tables (mean -22 cm), especially in zones of seasonal groundwater discharge, artefacts of the extraction history. Forest cover expanded from 5 to 20% of the study area following abandonment. The effect of forest growth (transpiration and interception) and drainage on lowering water levels eventually will be countered by slower water movement through the increasingly dense soil, and by natural ditch deterioration. However, without management intervention, full re-establishment of natural hydrological functions will take a very long time.

Physical and chemical characteristics of fibrous peat

NASA Astrophysics Data System (ADS)

Sutejo, Yulindasari; Saggaff, Anis; Rahayu, Wiwik; Hanafiah

2017-11-01

Banyuasin is one of the regency in South Sumatera which has an area of 200.000 Ha of peat land. Peat soil are characterized by high compressibility parameters and low initial shear strength. Block sampling method was used to obtain undisturbed sample. The results of this paper describe the characteristics of peat soil from physical and chemical testing. The physical and chemical characteristics of peat include water content (ω), specific gravity (Gs), Acidity (pH), unit weight (γ), and ignition loss tests. SEM and EDS test was done to determine the differences in fiber content and to analyze chemical elements of the specimen. The average results ω, Gs, and pH are 263.538 %, 1.847, and 3.353. Peat is classified in H4 (by Von Post). The results of organic content (OC), ash content (AC), and fiber content (FC) are found 78.693 %, 21.310 %, and 73.703 %. From the results of physical and chemical tests, the peat in Banyuasin is classified as fibrous peat. All the results of the characteristics and classification of fibrous peat compared with published data were close.

Excavating and loading equipment for peat mining

NASA Astrophysics Data System (ADS)

Mikhailov, A. V.; Zhigulskaya, A. I.; Yakonovskaya, T. B.

2017-10-01

Recently, the issues of sustainable development of Russian regions, related to ensuring energy security, are more urgent than ever. To achieve sustainable development, an integrated approach to the use of local natural resources is needed. Practically in all north regions of the Russian Federation, peat as a local natural resource is widespread, which has a practical application in the area of housing services. The paper presents the evaluation of technologies for open-pit peat mining, as well as analysis of technological equipment for peat production. Special attention is paid to a question of peat materials excavating and loading. The problem of equipment selection in a peat surface mine is complex. Many features, restrictions and criteria need to be considered. Use of low and ultra-low ground pressure excavators and low ground pressure front-end loaders with full-range tires to provide the necessary floatation in the peat bog environment is offered.

Effects of a raised water table on greenhouse gas emissions and celery yield from agricultural peat under climate warming conditions

NASA Astrophysics Data System (ADS)

Matysek, Magdalena; Zona, Donatella; Leake, Jonathan; Banwart, Steven

2017-04-01

Peatlands are globally important areas for carbon preservation: covering only 3% of world's land, they store 30% of total soil carbon. At the same time, peat soils are widely utilised in agriculture: in Europe 14% of peatland area is under cultivation, 40% of UK peatlands have been drained for agricultural use and 24% of deep peat area in England is being farmed. One of the most important regions for crop production on lowland peats in the UK are the East Anglian Fenlands (the Fens): an area of drained peatlands in East England. 88% of the Fenland area is cultivated, sustaining around 4000 farms and supplying 37% of total vegetable production in England. The soils of the area are fertile (89% of agricultural land being classified as grade 1 or 2) and so crops with high nutritional demands tend to dominate. It is estimated that Fenland peats store 41 Tg of Carbon, which is lost from the ecosystem at a rate of 0.4 Tg C/yr. The Fens are at risk due to continued drainage-induced volume loss of the peat layer via shrinkage, compaction and oxidation, which are estimated to result in wastage rate of 2.1 cm/yr. Cultivation of peat soil requires drainage as most crops are intolerant of root-zone anoxia: this leads to creation of oxic conditions in which organic matter becomes vulnerable to mineralisation by aerobic microorganisms. It is, therefore, crucial to find a water table level which would minimise peat loss and at the same time allow for economically viable crop growth. Despite the importance of preservation of agricultural peats, there is a lack of studies which attempt to find water table level that strikes a balance between crop yield and greenhouse gas production. The future of the Fens is overshadowed by another uncertainty: increases in temperature brought by the climate change. It is estimated that average global temperature increase expected by the end of this century (relative to 1986-2005) would be within the range of 0.3-4.8°C, depending on the scenario. Rising temperatures should accelerate the rate of organic matter mineralisation, which will lead to higher emissions of greenhouse gases as well as enhanced plant growth due to better availability of nutrients. The effects of higher temperatures on crop growth and greenhouse gas emission have not been properly investigated in the context of agriculturally-utilised peatlands. This study was conducted on peat cores excavated from a field in the Fens and focused on the following objectives: 1. To examine effects of climate change-induced temperature rises on celery productivity and peat CO2 and CH4 emissions. 2. To find the field water table level that reduces peat emissions of CO2 and CH4 while maintaining celery productivity. The research found higher CO2 emissions from the elevated (+5°C) temperature treatment and lower CO2 emissions from the higher (-30cm) water table level, however, noted no effect on CH4 emissions of any of the treatments. The higher water table decreased aboveground celery biomass. There was no effect of increased temperature on aboveground celery yield.

Mechanisms controlling Cu, Fe, Mn, and Co profiles in peat of the Filson Creek Fen, northeastern Minnesota

USGS Publications Warehouse

Walton-Day, K.; Filipek, L.H.; Papp, C.S.E.

1990-01-01

Filson Creek Fen, located in northeastern Minnesota, overlies a Cu-Ni sulfide deposit. A site in the fen was studied to evaluate the hydrogeochemical mechanisms governing the development of Fe, Mn, Co, and Cu profiles in the peat. At the study site, surface peat approximately 1 m thick is separated from the underlying mineralized bedrock by a 6-12 m thickness of lake and glaciofluvial sediments and till. Concentrations of Fe, Mn, Co, and Cu in peat and major elements in pore water delineate a shallow, relatively oxidized, Cu-rich zone overlying a deeper, reduced, Fe-, Mn-, and Co-rich zone within the peat. Sequential metal extractions from peat samples reveal that 40-55% of the Cu in the shallow zone is associated with organic material, whereas the remaining Cu is distributed between iron-oxide, sulfide, and residual fractions. Sixty to seventy percent of the Fe, Mn, and Co concentrated in the deeper zone occur in the residual phase. The metal profiles and associations probably result from non-steady-state input of metals and detritus into the fen during formation of the peat column. The enrichment of organic-associated Cu in the upper, oxidized zone represents a combination of Cu transported into the fen with detrital plant fragments and soluble Cu, derived from weathering of outcrop and subcrop of the mineral deposit, transported into the fen, and fixed onto organic matter in the peat. The variable stratigraphy of the peat indicates that weathering processes and surface vegetation have changed through time in the fen. The Fe, Mn, and Co maxima at the base of the peat are associated with a maximum in detrital matter content of the peat resulting from a transition between the underlying inorganic sedimentary environment to an organic sedimentary environment. The chemistry of sediments and ground water collected beneath the peat indicate that mobilization of metals from sulfide minerals in the buried mineral deposit or glacial deposits is minimal. Therefore, the primary source of Cu to the peat at the study site is outcrops and shallow subcrops of the mineral deposit adjacent to the fen. ?? 1990.

Determining critical groundwater level to prevent degraded peatland from severe peat fire

NASA Astrophysics Data System (ADS)

Putra, E. I.; Cochrane, M. A.; Vetrita, Y.; Graham, L.; Saharjo, B. H.

2018-05-01

Peat fires have been a severe recurrent problem for Indonesia, but droughts due to prolonged dry season aggravate burning conditions. To get a better understanding of this issue, we studied fire conditions in a portion of the ex-Mega Rice Project (MRP) area, Central Kalimantan. To examine fire season and hydrology factors affecting peat fires we analyzed daily TRMM data, Nino 3.4 SST Anomalies, and changing groundwater levels (GWL) from 300 dipwells. Our results quantify time-lags between the period of lowest precipitation and the lowest GWL; providing some ability to predict fire risk in advance of the lowest GWL. The rise of Nino 3.4 SST anomalies is significant risk factors for peat fire as they signify dry months which may yield large fire occurrences. GWL in 2011 was lower than in 2012, but fires were more frequent in 2012, indicating that low precipitation amounts in the wet season of 2011/2012 left the peat in a dry condition early in 2012. Most of the fires occurred in areas with GWL less than -30 cm, powerfully illustrating the importance of maintaining GWL at more than -10 cm, to prevent degraded peatlands from experiencing surface and deep peat fires.

High diversity of tropical peatland ecosystem types in the Pastaza-Marañón basin, Peruvian Amazonia

NASA Astrophysics Data System (ADS)

LäHteenoja, Outi; Page, Susan

2011-06-01

Very little information exists on Amazonian peatlands with most studies on tropical peatlands concentrating on Southeast Asia. Here we describe diversity of Amazonian peatland ecosystems and consider its implications for the global diversity of tropical peatland ecosystems. Nine study sites were selected from within the most extensive wetland area of Peruvian Amazonia: the 120,000 km2 Pastaza-Marañón basin. Peat thickness was determined every 500 m from the edge toward the center of each site, and peat samples were collected from two cores per site. Samples from the entire central core and surface samples from the other core were analyzed for nutrient content. Topography of four peat deposits was measured. In order to study differences in vegetation, pixel values were extracted from a satellite image. The surface peat nutrient content of the peatlands varied from very nutrient-rich to nutrient-poor. Two of the peatlands measured for their topography were domed (5.4 and 5.8 m above the stream), one was gently sloping (1.4 m above the stream), and one was flat and occurred behind a 7 m high levee. Five different peatland vegetation types were detected on the basis of pixel values derived from the satellite image. The peat cores had considerable variation in nutrient content and showed different developmental pathways. In summary, the Pastaza-Marañón basin harbors a considerable diversity of previously undescribed peatland ecosystems, representing a gradient from atmosphere-influenced, nutrient-poor ombrotrophic bogs through to river-influenced, nutrient-rich swamps. Their existence affects the habitat diversity, carbon dynamics, and hydrology of the Amazonian lowlands, and they also provide an undisturbed analog for the heavily disturbed peatlands of Southeast Asia. Considering the factors threatening the Amazonian lowlands, there is an urgent need to investigate and conserve these peatland ecosystems, which may in the near future be among the very few undisturbed tropical ombrotrophic bogs remaining in the world.

Peat Formation on Minjerribah (North Stradbroke Island), subtropical eastern Australia

NASA Astrophysics Data System (ADS)

Moss, Patrick; Tibby, John; Barr, Cameron; Weerensena, Chagi; Gontz, Allen; Petherick, Lynda

2016-04-01

Minjerribah (North Stradbroke Island) is the second largest sand island in the world and contains extensive peat dominated wetlands, comprising ~20% of the total area of the island. These wetland systems include large areas of estuarine swamps [mainly mangrove forest (~16% of the island's wetland area)], freshwater swamps [both herb (~58% of the island's wetland area) and tree dominated (~20% of the island's wetland area)] and numerous lake systems [both perched and window lakes (~2% of the island's wetland area)]. This presentation will examine peat formation processes at four wetland sites: a late Holocene prograding beach system (Flinders Beach); a 150,000 year lacustrine system (Welsby Lagoon 1), as well as a late Holocene lacustrine/palustrine system (Welsby Lagoon 2); and a late Quaternary lacustrine/palustrine system (Tortoise Lagoon), as well as discussing broader environmental characteristics of Minjerribah's nationally and internationally important wetland systems.

Impact of water conditions on land surface subsidance and the decline of organic soils in Kuwasy peatland

NASA Astrophysics Data System (ADS)

Chrzanowski, S.; Szajdak, L.

2009-04-01

Organic soils as result of drainage undergo consolidation, mineralization, and subsidence of surface layer, and decline of organic matter. The rate of the subsidence of surface layer depends on a number of factors, such as ground water level, kind of peat, density of thickness of peat layer, drainage depth, climate, land use and drainage duration. These processes are connected with the changes of physical properties and lead to the conversion of organic soils into mineral-organic and mineral. The phenomena are observed in Biebrza, Notec Valley, and Kurpiowska Basin and Wieprz-Krzna channel. During last 42 years, in Kuwasy peatland from 10-13 ton per year was declined and the area of peatland decreased from 53 to 57 cm. It was observed that, peat moorsh soil of the first stadium of moorshification located on a middle decomposed peat transformed into peat-moorh soil of the second stadium of moorshification located on a high decomposed peat. However shallow peat soils were converted into mineral-moorsh and moorsh. Kuwasy peatland was meliorated twice in XX century, first one in the middle of 30 and second one in 50. It led to the farther land surface subsidence and decline of organic matter. The aim of this investigation was to evaluate the rate of land surface subsidence, decline of the area and the transformation of physic-water properties in peat-moorsh soil of different water conditions. The investigations were carried out in Kuwasy peatland, located in Biebrza Basin North-East Poland. In peat soil samples ash contents, porosity, pF curves and bulk density were determined. The analysis of these results allowed to evaluate long-term soil subsidence and to relate it to soil water conditions.

Impacts of fire on nitrogen cycling in aquatic and terrestrial ecosystems in the Yukon-Kuskokwim River Delta, AK

NASA Astrophysics Data System (ADS)

Schade, J. D.; Jardine, L. E.; Bristol, E. M.; Navarro-Perez, E.; Melton, S.; Jimmie, J. A.; Natali, S.; Mann, P. J.; Holmes, R. M.

2016-12-01

Global climate change is having a disproportionate impact on northern high latitudes, including rapid increases in temperature, changes in precipitation, and increasing fire frequency and severity. Wildfires have been shown to strongly influence ecosystem processes through acceleration of permafrost thaw and increased nitrogen (N) availability, the effects of which may increase gaseous loss of carbon (C) to the atmosphere, increase primary production by alleviating N limitation, or both. The extent of these fire impacts has not been well-documented in the Arctic, particularly in areas of discontinuous permafrost. In 2015, the Yukon-Kuskokwim River Delta (YK Delta) in southwestern Alaska experienced the largest fire season in recorded history, providing an opportunity to study wildfire impacts on an area particularly vulnerable to permafrost thaw. Our objectives were to study the impacts of these fires on nitrogen availability in a range of land cover classes, including peat plateaus, channel fens, and aquatic ecosystems distributed across the landscapes. We sampled soils from several vegetation patches on burned and unburned peat plateaus, and soil and surface waters from fens, small ponds, and streams downslope of these sites. All water samples were filtered through GFF filters in the field. Soils were transported frozen to the Woods Hole Research Center and extracted in KCl. All water samples and extracts were analyzed for NH4 and NO3 concentrations. We found substantially higher concentrations of extractable NH4 in burned soils, but very little extractable NO3 in either burned or unburned soils. Water samples also showed higher NH4 in aquatic ecosystems in burned watersheds, but, in contrast to soils, showed relatively high NO3 concentrations, particularly in waters from lower landscape positions. Overall, aquatic ecosystems exhibited higher NO3: NH4 ratios than soil extractions, and increasing NO3: NH4 downslope. These results suggest significant export of nitrogen after fire and the potential for nitrification as N is transported across the landscape. These changes in N cycling are likely to have substantial consequences for the recovery of plant communities post-fire and for microbial processes and greenhouse gas fluxes, including N2O, from burned watersheds.

Impacts of fire on nitrogen cycling in aquatic and terrestrial ecosystems in the Yukon-Kuskokwim River Delta, AK

NASA Astrophysics Data System (ADS)

Schade, J. D.; Jardine, L. E.; Bristol, E. M.; Navarro-Perez, E.; Melton, S.; Jimmie, J. A.; Natali, S.; Mann, P. J.; Holmes, R. M.

2017-12-01

Global climate change is having a disproportionate impact on northern high latitudes, including rapid increases in temperature, changes in precipitation, and increasing fire frequency and severity. Wildfires have been shown to strongly influence ecosystem processes through acceleration of permafrost thaw and increased nitrogen (N) availability, the effects of which may increase gaseous loss of carbon (C) to the atmosphere, increase primary production by alleviating N limitation, or both. The extent of these fire impacts has not been well-documented in the Arctic, particularly in areas of discontinuous permafrost. In 2015, the Yukon-Kuskokwim River Delta (YK Delta) in southwestern Alaska experienced the largest fire season in recorded history, providing an opportunity to study wildfire impacts on an area particularly vulnerable to permafrost thaw. Our objectives were to study the impacts of these fires on nitrogen availability in a range of land cover classes, including peat plateaus, channel fens, and aquatic ecosystems distributed across the landscapes. We sampled soils from several vegetation patches on burned and unburned peat plateaus, and soil and surface waters from fens, small ponds, and streams downslope of these sites. All water samples were filtered through GFF filters in the field. Soils were transported frozen to the Woods Hole Research Center and extracted in KCl. All water samples and extracts were analyzed for NH4 and NO3 concentrations. We found substantially higher concentrations of extractable NH4 in burned soils, but very little extractable NO3 in either burned or unburned soils. Water samples also showed higher NH4 in aquatic ecosystems in burned watersheds, but, in contrast to soils, showed relatively high NO3 concentrations, particularly in waters from lower landscape positions. Overall, aquatic ecosystems exhibited higher NO3: NH4 ratios than soil extractions, and increasing NO3: NH4 downslope. These results suggest significant export of nitrogen after fire and the potential for nitrification as N is transported across the landscape. These changes in N cycling are likely to have substantial consequences for the recovery of plant communities post-fire and for microbial processes and greenhouse gas fluxes, including N2O, from burned watersheds.

How important are peatlands globally in providing drinking water resources?

NASA Astrophysics Data System (ADS)

Xu, Jiren; Morris, Paul; Holden, Joseph

2017-04-01

The potential role of peatlands as water stores and sources of downstream water resources for human use is often cited in publications setting the context for the importance of peatlands, but is rarely backed up with substantive evidence. We sought to determine the global role of peatlands in water resource provision. We developed the Peat Population Index (PPI) that combines the coverage of peat and the local population density to show focused (hotspot) areas where there is a combination of both large areas of peat and large populations who would potentially use water sourced from those peatlands. We also developed a method for estimating the proportion of river water that interacted with contributing peatlands before draining into rivers and reservoirs used as a drinking water resource. The Peat Reservoir Index (PRI) estimates the contribution of peatlands to domestic water use to be 1.64 km3 per year which is 0.35 % of the global total. The results suggest that although peatlands are widespread, the spatial distribution of the high PPI and PRI river basins is concentrated in European middle latitudes particularly around major conurbations in The Netherlands, northern England, Scotland (Glasgow) and Ireland (Dublin), although there were also some important systems in Florida, the Niger Delta and Malaysia. More detailed research into water resource provision in high PPI areas showed that they were not always also high PRI areas as often water resources were delivered to urban centres from non-peat areas, despite a large area of peat within the catchment. However, particularly in the UK and Ireland, there are some high PRI systems where peatlands directly supply water to nearby urban centres. Thus both indices are useful and can be used at a global level while more local refinement enables enhanced use which supports global and local peatland protection measures. We now intend to study the impacts of peatland degradation and climate change on water resource provision in hotspot PPI and PRI regions.

Development of low-ash, planar peat swamps in an alluvial-plain setting: The no. 5 Block beds (westphalian D) of southern West Virginia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Staub, J.R.; Richards, B.K.

1993-07-01

Coals from the No. 5 Block coal beds (Westphalian D) of the central Appalachian basin are noted for their blocky, dull character and their low ash and low sulfur content. The beds are multiple benched, with rock partings separating benches. Individual benches have limited lateral extent and, where thick, are dominated by bright, high-ash coal at the base and dull, low-ash coal in the upper parts. The duller coals contain more exinite-group and inertinite-group macerals than the brighter coals. These coal beds are encased in sandstone units dominated by fining-upward sequences. The overall depositional setting is an alluvial-plain environment withmore » northwest-flowing channels spaced approximately 20 km apart. The channels were flanked by clastic swamps about 7 km wide. Low-ash peat accumulated in areas of the flood plain most distant from the channels. These peat-accumulating swamps were about 8 km across. In a few instances low-frequency flood events introduced fine siliciclastic sediment into the peat swamps, depositing a thin layer of sediment on top of the peat. This sediment layer is thicker where the underlying coal is the thickest. These thick coal areas are topographically lower than surrounding coal areas. This relationship between coal thickness, parting thickness, and topography indicates that these peat swamps were planar at the time of deposition. Individual coal benches contain abundant preserved cellular tissue (telocollinite, semifusinite, and fusinite) at most locations, suggesting that robust vegetation was widespread in the swamps and that the morphology was planar. The high concentrations of exinite-group an inertinite-group macerals in the upper parts of benches resulted from selective decomposition and oxidation of the peat in subaerial and aquatic planar-swamp environments.« less

SPRUCE Deep Peat Heating Manipulations: in situ Methods to Characterize the Response of Deep Peat to Warming

NASA Astrophysics Data System (ADS)

Hanson, P. J.; Riggs, J. S.; Barbier, C. N.; Nettles, W. R., IV; Phillips, J. R.; Hook, L.

2014-12-01

Deep soil heating infrastructure was completed in 2014 for a peatland whole-ecosystem warming study that will include air warming starting in 2015 (SPRUCE; http://mnspruce.ornl.gov). In June 2014, we initiated deep soil heating to test the responsiveness of deep peat carbon stocks, microbial communities and biogeochemical cycling processes to heating at 4 warming levels (+2.25, +4.5, +6.75 and +9 °C; 2 replicate plots) compared to fully-constructed control plots (+0 °C; 2 replicate plots). The warming treatments were deployed over eight 113 m2 areas using circular arrays of low-wattage (W) electrical resistance heaters. Perimeter heating was achieved by an exterior circle of 48 100W heaters that apply heat from the surface to a depth of 3 meters. Heating within the study area was accomplished utilizing three zones of 100W "deep only" heaters: an intermediate circle of 12 units, an interior circle of 6 units and one unit placed at the plot center. Heating elements inside the study area apply heat only from -2 to -3 m to keep active heater surfaces away from measured peat volumes. With an average peat depth of 2.5 meters this system was able to warm approximately 113 of the 282 m3 of peat within each target plot. In the absence of the air warming cap, in situ deep peat heating is only effective at sustaining warming in the deep peat layers. Warming levels at depth were achieved over a 25-day (+ 2.25 °C) to a 60-day (+9 °C) period depending on the target treatment temperatures in agreement with a priori energy balance model simulations. Homogeneous temperature distributions between heaters at a given depth interval continued to develop after these targets were reached. Biological and biogeochemical responses to these manipulations are being actively assessed. After one month of transient heating, data for ground-level surface flux of CO2 and CH4 had not shown changes from deep peat heating, but they continue to be tracked and will be summarized in this and related talks.

Fractionation of (137)Cs and Pu in natural peatland.

PubMed

Mihalík, Ján; Bartusková, Miluše; Hölgye, Zoltán; Ježková, Tereza; Henych, Ondřej

2014-08-01

High Cs-137 concentrations in plants growing on peatland inspired us to investigate the quantity of its bioavailable fraction in natural peat. Our investigation aims to: a) estimate the quantity of bioavailable Cs-137 and Pu present in peat, b) verify the similarity of Cs-137 and K-40 behaviours, and c) perform a quantification of Cs-137 and Pu transfer from peat to plants. We analysed the vertical distribution of Cs-137 and Pu isotopes in the peat and their concentrations in plants growing on these places. Bioavailability of radionuclides was investigated by sequential extraction. Sequential analyses revealed that it was the upper layer which contained the majority of Cs-137 in an available form while deeper layers retained Cs-137 in immobile fractions. We can conclude that 18% of all Cs-137 in the peat is still bioavailable. Despite of the low quantity of bioavailable fraction of Cs-137 its transfer factor reached extremely high values. In the case of Pu, 64% of its total amount was associated with fulvic/humic acids which resulted in the high transfer factor from peat to plants. 27 years after the Chernobyl nuclear accident, the significant part of radionuclides deposited in peatland is still bioavailable. Copyright © 2014 Elsevier Ltd. All rights reserved.

Evaluating the hydraulic and transport properties of peat soil using pore network modeling and X-ray micro computed tomography

NASA Astrophysics Data System (ADS)

Gharedaghloo, Behrad; Price, Jonathan S.; Rezanezhad, Fereidoun; Quinton, William L.

2018-06-01

Micro-scale properties of peat pore space and their influence on hydraulic and transport properties of peat soils have been given little attention so far. Characterizing the variation of these properties in a peat profile can increase our knowledge on the processes controlling contaminant transport through peatlands. As opposed to the common macro-scale (or bulk) representation of groundwater flow and transport processes, a pore network model (PNM) simulates flow and transport processes within individual pores. Here, a pore network modeling code capable of simulating advective and diffusive transport processes through a 3D unstructured pore network was developed; its predictive performance was evaluated by comparing its results to empirical values and to the results of computational fluid dynamics (CFD) simulations. This is the first time that peat pore networks have been extracted from X-ray micro-computed tomography (μCT) images of peat deposits and peat pore characteristics evaluated in a 3D approach. Water flow and solute transport were modeled in the unstructured pore networks mapped directly from μCT images. The modeling results were processed to determine the bulk properties of peat deposits. Results portray the commonly observed decrease in hydraulic conductivity with depth, which was attributed to the reduction of pore radius and increase in pore tortuosity. The increase in pore tortuosity with depth was associated with more decomposed peat soil and decreasing pore coordination number with depth, which extended the flow path of fluid particles. Results also revealed that hydraulic conductivity is isotropic locally, but becomes anisotropic after upscaling to core-scale; this suggests the anisotropy of peat hydraulic conductivity observed in core-scale and field-scale is due to the strong heterogeneity in the vertical dimension that is imposed by the layered structure of peat soils. Transport simulations revealed that for a given solute, the effective diffusion coefficient decreases with depth due to the corresponding increase of diffusional tortuosity. Longitudinal dispersivity of peat also was computed by analyzing advective-dominant transport simulations that showed peat dispersivity is similar to the empirical values reported in the same peat soil; it is not sensitive to soil depth and does not vary much along the soil profile.

Emissions of volatile organic compounds and particulate matter from small-scale peat fires

NASA Astrophysics Data System (ADS)

George, I. J.; Black, R.; Walker, J. T.; Hays, M. D.; Tabor, D.; Gullett, B.

2013-12-01

Air pollution emitted from peat fires can negatively impact regional air quality, visibility, climate, and human health. Peat fires can smolder over long periods of time and, therefore, can release significantly greater amounts of carbon into the atmosphere per unit area compared to burning of other types of biomass. However, few studies have characterized the gas and particulate emissions from peat burning. To assess the atmospheric impact of peat fires, particulate matter (PM) and volatile organic compounds (VOCs) were quantified from controlled small-scale peat fire experiments. Major carbon emissions (i.e. CO2, CO, methane and total hydrocarbons) were measured during the peat burn experiments. Speciated PM mass was also determined from the peat burns from filter and polyurethane foam samples. Whole air samples were taken in SUMMA canisters and analyzed by gas chromatography-mass spectrometry to measure 82 trace VOCs. Additional gaseous carbonyl species were measured by sampling with dinitrophenylhydrazine-coated cartridges and analyzed with high performance liquid chromatography. VOCs with highest observed concentrations measured from the peat burns were propylene, benzene, chloromethane and toluene. Gas-phase carbonyls with highest observed concentrations included acetaldehyde, formaldehyde and acetone. Emission factors of major pollutants will be compared with recommended values for peat and other biomass burning.

Organic matter loss from cultivated peat soils in Sweden

NASA Astrophysics Data System (ADS)

Berglund, Örjan; Berglund, Kerstin

2015-04-01

The degradation of drained peat soils in agricultural use is an underestimated source of loss of organic matter. Oxidation (biological degradation) of agricultural peat soils causes a loss of organic matter (OM) of 11 - 22 t ha-1 y-1 causing a CO2 emission of 20 - 40 t ha-1 y-1. Together with the associated N2O emissions from mineralized N this totals in the EU to about 98.5 Mton CO2 eq per year. Peat soils are very prone to climate change and it is expected that at the end of this century these values are doubled. The degradation products pollute surface waters. Wind erosion of peat soils in arable agriculture can cause losses of 3 - 30 t ha-1 y-1 peat also causing air pollution (fine organic particles). Subsidence rates are 1 - 2 cm per year which leads to deteriorating drainage effect and make peat soils below sea or inland water levels prone to flooding. Flooding agricultural peat soils is in many cases not possible without high costs, high GHG emissions and severe water pollution. Moreover sometimes cultural and historic landscapes are lost and meadow birds areas are lost. In areas where the possibility to regulate the water table is limited the mitigation options are either to increase biomass production that can be used as bioenergy to substitute some fossil fuel, try to slow down the break-down of the peat by different amendments that inhibit microbial activity, or permanent flooding. The negative effects of wind erosion can be mitigated by reducing wind speed or different ways to protect the soil by crops or fiber sheets. In a newly started project in Sweden a typical peat soil with and without amendment of foundry sand is cropped with reed canary grass, tall fescue and timothy to investigate the yield and greenhouse gas emissions from the different crops and how the sand effect the trafficability and GHG emissions.

Effect of water-table fluctuations on the degradation of Sphagnum phenols in surficial peats

NASA Astrophysics Data System (ADS)

Abbott, Geoffrey D.; Swain, Eleanor Y.; Muhammad, Aminu B.; Allton, Kathryn; Belyea, Lisa R.; Laing, Christopher G.; Cowie, Greg L.

2013-04-01

A much improved understanding of how water-table fluctuations near the surface affect decomposition and preservation of peat-forming plant litter and surficial peats is needed in order to predict possible feedbacks between the peatland carbon cycle and the global climate system. In this study peatland plants (bryophytes and vascular plants), their litter and peat cores were collected from the Ryggmossen peatland in the boreonemoral zone of central Sweden. The extracted insoluble residues from whole plant tissues were depolymerized using thermally assisted hydrolysis and methylation (THM) in the presence of both unlabelled and 13C-labelled tetramethylammonium hydroxide (TMAH) which yielded both vascular plant- and Sphagnum-derived phenols. Methylated 4-isopropenylphenol (IUPAC: 1-methoxy-4-(prop-1-en-2-yl)benzene), methylated cis- and trans-3-(4'-hydroxyphen-1-yl)but-2-enoic acid (IUPAC: (E/Z)-methyl 3-(4-methoxyphenyl)but-2-enoate), and methylated 3-(4'-hydroxyphen-1-yl)but-3-enoic acid (IUPAC: methyl 3-(4-methoxyphenyl)but-3-enoate) (van der Heijden et al., 1997) are confirmed as TMAH thermochemolysis products of "bound" sphagnum acid and also as being specific to Sphagnum mosses. These putative biomarkers were also significant components in the unlabelled TMAH thermochemolysis products from the depolymerization of ultrasonically extracted samples from eight peat cores, one from a hummock and one from a hollow at each of the four stages along the bog plateau-to-swamp forest gradient. We have proposed and measured two parameters namely (i) σ which is defined as the total amount of these four molecules normalised to 100 mg of OC; and (ii) an index (SR%) which is the ratio of σ to the Λ parameter giving a measure of the relative amounts of "bound" sphagnum acid to the "bound" vascular plant phenols in peat moss and the surficial peat layers. Changes in σ and SR% down the bog plateau (BP), bog margin (BM) and fen lagg (FL) cores in the Ryggmossen mire indicates that the sphagnum acid bound into the peat is being degraded in the unsaturated and seasonally-saturated layers. There is then a stabilisation of Sphagnum-derived phenols in the deepest horizons of the seasonally-saturated layer and into the permanently-saturated layer. These results suggest that "bound" sphagnum acid will be stabilised in peatlands shifting to a wetter and more variable precipitation regime whereas it will be gradually stripped away (e.g. by hydrolysis/enzymatic activity) in surficial peats shifting to a drier climate, such that any subsequent rewetting of the peat could lead to anaerobic hydrolysis and fermentation of the newly exposed carbohydrates. This highlights the sensitivity of Sphagnum surficial peats to climate-induced changes in water levels albeit there may be differences in the extent of degradation along the bog-fen gradient.

Global latitudinal trends in peat recalcitrance quantified with calibrated FTIR spectroscopy

NASA Astrophysics Data System (ADS)

Hodgkins, S. B.; Richardson, C. J.; Dommain, R.; Wang, H.; Glaser, P. H.; Verbeke, B. A.; Rogers, K.; Winkler, B. R.; Missilmani, M.; Flanagan, N. E.; Ho, M.; Hoyt, A.; Harvey, C. F.; Cobb, A.; Rich, V. I.; Vining, S. R.; Hough, M.; Saleska, S. R.; Podgorski, D. C.; Tfaily, M. M.; Wilson, R.; Holmes, B.; de La Cruz, F.; Toufaily, J.; Hamdan, R.; Cooper, W. T.; Chanton, J.

2017-12-01

Peatlands are a major global carbon reservoir (528-600 Pg). Most peat is found at high latitudes, where organic matter decomposition is slowed by cold temperatures and water-saturated conditions. Nonetheless, a significant portion of global peatland carbon (10-30%) is in tropical peatlands. The factors that allow peat accumulation in warm climates remain uncertain, raising the question of whether these factors may preserve peat in boreal regions as they warm. In this study, we examined peat and plant chemistry across a latitudinal transect from the Arctic to the tropics. Carbohydrate and aromatic contents were estimated based on a newly-developed analysis method for Fourier transform infrared (FTIR) spectra. In this method, peaks are baseline-corrected and normalized to the integrated spectral area using an automated R script, then calibrated to known concentrations using standards. This technique showed trends that were in agreement with those seen with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and 13C-NMR spectroscopy. Along the latitudinal transect, we found that near-surface (sub)tropical peat has lower carbohydrate and greater aromatic content than near-surface high-latitude peat, leading to recalcitrance that allows (sub)tropical peat to persist despite warm temperatures. The chemistry of (sub)tropical peat reflects a combination of recalcitrant plant inputs, and more extensive humification driven by higher temperatures. Because we observed similar declines in carbohydrate content with depth in high-latitude peat deposits, our data explain recent field-scale deep peat warming experiments in which catotelm (deeper) peat remained stable in the face of temperature increases up to 9 °C. We suggest that high-latitude deep peat reservoirs may be stabilized in the face of climate change by their ultimately lower carbohydrate and higher aromatic composition, similar to tropical peats.

Some peat deposits in Penobscot County, Maine

USGS Publications Warehouse

Cameron, Cornelia Clermont; Anderson, Walter A.

1979-01-01

Twenty of the peat deposits in Penobscot County, Maine contain an estimated 29,282,000 short tons air-dried peat. The peat is chiefly sphagnum moss and reed-sedge of high quality according to ASTM standards for agricultural and horticultural use. Analyses show that this same volume has high fuel value, low sulfur and high hydrogen contents compared with lignite and sub-bituminous coal, which may indicate that it also has potential for fuel use. On the basis of the metallic trace element content, one area within the region containing the 20 deposits has been delineated for further bedrock studies.

Comparisons of soil nitrogen mass balances for an ...

EPA Pesticide Factsheets

We compared the N budgets of an ombrotrophic bog and a minerotrophic fen to quantify the importance of denitrification in peatlands and their watersheds. We also compared the watershed upland mineral soils to bog/fen peat; lagg and transition zone peat to central bog/fen peat; and surface, mid-layer and deep soil and peat horizons. Bog and fen area were derived from a wetland boundary GIS data layer, and bog and fen volumes were calculated as the interpolated product of area and depth of peat. Atmospheric N deposition to the bog and fen were based on measurements from a station located 2km north of the bog watershed and 0.5km from the fen watershed. Precipitation was analyzed for nitrate (NO3-), ammonium (NH4+), and total N (TN), and aggregated to annual values. Outflow water samples from the bog and fen were collected as surface grab samples on each of the May-October sampling dates over the 2010-2013 study, and were analyzed and aggregated annually as for atmospheric N. Soil and peat samples were analyzed for N content, and for net ammonification (AM), nitrification (NT), and ambient (DN) and potential (DEA) denitrification rates. Nitrogen mass balances are based on mean annual atmospheric deposition and outflow; soil and peat standing stocks of N, and mean annual estimates of DN, weighted for contributions of the uplands, lagg or transition zone, and bog or fen hollows and hummocks, and accounting for soil depth effects. Annual deposition of N species was: N

An ecologic study of peat landforms in Canada and Alaska

NASA Technical Reports Server (NTRS)

Glaser, P. H.

1986-01-01

The role of groundwater and surface runoff in controlling the water chemistry and development of peat landforms in northern Minnesota are described. The LANDSAT imagery taken duing spring break-up are particularly valuable in identifying potential zones of groundwater discharge. The vascular floras of raised bogs in eastern North Americas demonstrating the remarkabe uniformity of the ombrotrophic flora over broad geographic regions are described. The evolution of peat landforms in the major boreal peatlands of eastern America is examined. The LANDSAT imagery is used to determine the area of patterned to featureless peatlands, the area of ombrotrophic bog relative to minerotrophic fen, and the relative size and degree of streamlining of island landforms entirely composed of peat. Such measurements can be used to assess the role of climate, time, and hydrology in controlling the formation of peatland patterns across broad geographic regions.

Hybrid biosorbents for removal of pollutants and remediation

NASA Astrophysics Data System (ADS)

Burlakovs, Juris; Klavins, Maris; Robalds, Artis; Ansone, Linda

2014-05-01

For remediation of soils and purification of polluted waters, wastewaters, biosorbents might be considered as prospective groups of materials. Amongst them peat have a special role due to low cost, biodegradability, high number of functional groups, well developed surface area and combination of hydrophilic/hydrophobic structural elements. Peat as sorbent have good application potential for removal of trace metals, and we have demonstrated peat sorption capacities, sorption kinetics, thermodynamics in respect to metals with different valencies - Tl(I), Cu(II), Cr(III). However, peat sorption capacity in respect to nonmetallic (anionic species) elements is low. Also peat mechanical properties do not support application in large scale column processes thereby, to expand peat application sphere, the approach of biomass based hybrid sorbents has been elaborated. The concept "hybrid sorbent" in understanding of biosorbent means natural, biomass based modified material, covered with another sorbent material, thus combining properties of both such as sorbent functionalities, surface properties etc. As the "covering layer" both inorganic substances, mineral phases (iron oxohydroxides, oxyappatite) and organic polymers (using graft polymerization) were used. The obtained sorbents were characterised by their spectral properties, surface area and elemental composition. The obtained hybrid sorbents were tested for sorption of compounds in anionic speciation forms, for example of arsenic, antimony, tellurium and phosphorous compounds in comparison with weakly basic anionites. The highest sorption capacity was observed when peat sorbents modified with iron compounds were used. Sorption of different arsenic speciation forms onto iron-modified peat sorbents was investigated as a function of pH and temperature. It was established that sorption capacity increases with a rise in temperature as the calculation of sorption process thermodynamic parameters indicates the spontaneity of sorption process and its endothermic nature. The recycling options of obtained compounds after their saturation with metal or non-metallic species are suggested.

Investigation of smoldering combustion propagation of dried peat

NASA Astrophysics Data System (ADS)

Palamba, Pither; Ramadhan, M. L.; Imran, F. A.; Kosasih, E. A.; Nugroho, Y. S.

2017-03-01

Smoldering is a form of combustion characterised by flameless burning of porous materials. Smoldering combustion of porous and organic soil such as peat, is considered as a major contributor to haze problem during wildland fires in Sumatra and Kalimantan, Indonesia. With almost half of tropical peatland worldwide, and vast area that resulted in its rich agricultural diversity, Indonesia possessed many variants of peat throughout the region. Thus, further highlighting the importance of characterizing the thermal properties of different varieties of peats for further analysis. An experimental test method was built to analyse the differences of varying peats from different parts of Indonesia, regarding its smoldering combustion propagation. In this case, peat from Papua and South Sumatera were analysed. A cylindrical wire meshed container of 190 cm3 in volume, was filled with dried peat. The temperature data and mass loss during the smoldering combustion was gathered using thermocouples and a DAQ system. After the experimental apparatus was set, a smoldering combustion of the dried peats was initiated at the top of the container using an electric heater. The results of the experiment showed a smoldering temperature of about 600°C and with a smoldering propagation rate of about 4.50 to 4.75 cm/h for both peat samples.

Climate change impact on peatland and forest ecosystems of Russia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kondrasheva, N.Yu.; Kobak, K.I.; Turchinovich, I.Ye.

1996-12-31

Paleoclimatic and paleobotanic reconstructions allow a conclusion that ecosystems and natural zones significantly changed due to climate fluctuations. The average long-term carbon accumulation in peatlands of Russia was estimated as 45.6 mln tons of carbon per year. During the Holocene the rate of peat accumulation changed. During the Subboreal period the rate of peat accumulation gradually decreased to 17 gC/m2 yr, reaching its lowest value in the Subatlantic period. Apparently, the rate of peat accumulation decreased in Subboreal period due to sharp cooling and precipitation decrease. Future rates of peat accumulation might be higher than the present one. Forest ecosystemsmore » of north-western Russia also significantly changed during the Holocene. In Atlantic time the boundary between middle and south taiga was located 500 km northward compared to the present and broad-leaved forest occupied large areas. According to their forecast, a mean global air temperature increase by 1.4 C is expected to result in a considerable decrease in coniferous forest area and an increase in mixed and broad-leaved forest area.« less

Effects of Spontaneous Colonization by Eriophorum vaginatum on Belowground C and N Mobilization and Greenhouse Gas Emissions in a Restored Boreal Peatland

NASA Astrophysics Data System (ADS)

Lazcano, C.; Brummell, M.; Strack, M.

2016-12-01

Peatland restoration aims at recovering the ecological function of these ecosystems as active C sinks by re-establishing Sphagnum-dominated vegetation. In addition, restoration encourages the establishment of naturally occurring vascular plant species from the local seed bank. Whereas these plants could contribute to a substantial short-term increase in C sequestration due to their large biomass accumulation, their impacts on peat biogeochemistry are complex and belowground C and N mobilization could be substantial, leading to increased greenhouse gas emissions. We investigated the effects of cottongrass (Eriophorum vaginatum), a common vascular plant species colonizing extracted peatlands, on porewater dissolved organic C (DOC) and total dissolved N (TDN) as well as CO2, CH4 and N2O fluxes in a cutover boreal bog in Alberta (Canada), restored three years prior to the study. We hypothesized that cottongrass would increase the concentration of DOC and TDN in porewater as well as net N2O and CH4 emission from peat compared to areas of bare peat or moss. We studied porewater chemistry and net gas exchange for CO2, CH4, and N2O, using static chambers, over one growing season (May-September 2015) and we compared between plots containing cottongrass and plots lacking vascular plants. Plots were located along a transect of increasing water table, to discriminate between the effects of cottongrass and the prevailing hydrological conditions on porewater chemistry and gas fluxes. Cottongrass presence had contrasting effects on porewater DOC chemistry depending on wetness of the site, reducing DOC concentration in dry sites but increasing it at wet sites as compared with bare plots. This suggests that DOC mobilization is primarily controlled by hydrological conditions rather than cottongrass presence. However, cottongrass significantly increased CH4 emissions independently of the plot moisture. Cottongrass presence reduced net emission of N2O in the later part of the growing season, with cottongrass plots frequently acting as net consumers in July and August. Porewater TDN was significantly higher under cottongrass at the wettest area of the site than under either bare or cottongrass plots at the drier area, suggesting nitrogen mobilization from peat by an interaction between cottongrass roots and water.

Evaluation of dispersion methods for enumeration of microorganisms from peat and activated carbon biofilters treating volatile organic compounds.

PubMed

Khammar, Nadia; Malhautier, Luc; Degrange, Valérie; Lensi, Robert; Fanlo, Jean-Louis

2004-01-01

To enumerate microorganisms having colonized biofilters treating volatile organic compounds, it is necessary firstly to evaluate dispersion methods. Crushing, shaking and sonication were then tested for the removal of microflora from biofilters packing materials (peat and activated carbon). Continuous or discontinuous procedures, and addition of glass beads had no effect on the number of microorganisms removed from peat particles. The duration of treatment also had no effect for shaking and crushing, but the number of microorganisms after 60 min of treatment with ultrasound was significantly higher than that obtained after 0.5 min. The comparison between these methods showed that crushing was the most efficient for the removal of microorganisms from both peat and activated carbon. The comparison between three chemical dispersion agents showed that 1% Na-pyrophosphate was less efficient, compared with 200 mM phosphate buffer or 1% Na-hexametaphosphate. To optimize the cultivation of microorganisms, three different agar media were compared. Tryptic soy agar tenfold diluted (TSA 1/10) was the most suitable medium for the culture of microflora from a peat biofilter. For the activated carbon biofilter, there was no significant difference between Luria Bertoni, TSA 1/10, and plate count agar. The optimized extraction and enumeration protocols were used to perform a quantitative characterization of microbial populations in an operating laboratory activated carbon biofilter and in two parallel peat biofilters.

Peat hybrid sorbents for treatment of wastewaters and remediation of polluted environment

NASA Astrophysics Data System (ADS)

Klavins, Maris; Burlakovs, Juris; Robalds, Artis; Ansone-Bertina, Linda

2015-04-01

For remediation of soils and purification of polluted waters, wastewaters, sorbents might be considered as an prospective group of materials and amongst them peat have a special role due to low cost, biodegradability, high number of functional groups, well developed surface area and combination of hydrophilic/hydrophobic structural elements. Peat as sorbent have good application potential for removal of trace metals, and we have demonstrated peat sorption capacities, sorption kinetics, thermodynamics in respect to metals with different valencies - Tl(I), Cu(II), Cr(III). However peat sorption capacity in respect to nonmetallic (anionic species) elements is low. Also peat mechanical properties do not support application in large scale column processes. To expand peat application possibilities the approach of biomass based hybrid sorbents has been elaborated. The concept "hybrid sorbent" in our understanding means natural, biomass based sorbent modified, covered with another sorbent material, thus combining two types of sorbent properties, sorbent functionalities, surface properties etc. As the "covering layer" both inorganic substances, mineral phases (iron oxohydroxides, oxyapatite) both organic polymers (using graft polymerization) were used. The obtained sorbents were characterised by their spectral properties, surface area, elemental composition. The obtained hybrid sorbents were tested for sorption of compounds in anionic speciation forms, for example of arsenic, antimony, tellurium and phosphorous compounds in comparison with weakly basic anionites. The highest sorption capacity was observed when peat sorbents modified with iron compounds were used. Sorption of different arsenic speciation forms onto iron-modified peat sorbents was investigated as a function of pH and temperature. It was established that sorption capacity increases with a rise in temperature, and the calculation of sorption process thermodynamic parameters indicates the spontaneity of sorption process and its endothermic nature. The recycling options of obtained compounds after their saturation with metal or non-metallic species are suggested. Acknowledgement: Support from a project 2014/0009/1DP/1.1.1.2.0/13/APIA/VIAA/044

Reservoir-flooded river mouth areas as sediment traps revealing erosion from peat mining areas - Jukajoki case study in eastern Finland

NASA Astrophysics Data System (ADS)

Tahvanainen, Teemu; Meriläinen, Henna-Kaisa; Haraguchi, Akira; Simola, Heikki

2016-04-01

Many types of soil-disturbing land use have caused excess sedimentation in Finnish lakes. Identification and quantification of catchment sources of sediment material is crucial in cases where demands for remediation measures are considered. We studied recent (50 yr) sediments of four small rivers, all draining to a reservoir impounded in 1971. Catchments of two of the rivers had had peat mining activities from early 1980s until recently, exposing large areas of peat surfaces to erosion. The water level of the reservoir had risen to the river mouth areas of all rivers, while in each case, the river mouth areas still form riverine narrows separable from the main reservoir, hence collecting sedimentation from their own catchments. The original soils under the reservoir water level could readily be observed in core samples, providing a dated horizon under recent sediments. In addition, we used 137Cs-stratigraphies for dating of samples from original river bed locations. As expected, recent sediments of rivers with peat mining influence differed from others e.g. by high organic content and C:N ratios. Stable isotopes 13C and 15N both correlated with C:N (r = 0.799 and r = -0.717, respectively) and they also differentiated the peat-mining influenced samples from other river sediments. Principal components of the physical-chemical variables revealed clearer distinction than any variables separately. Light-microscopy revealed abundance of leafs of Sphagnum mosses in peat-mining influenced river sediments that were nearly absent from other rivers. Spores of Sphagnum were, however, abundant in all river sediments indicating their predominantly airborne origin. We find that combination of several physical-chemical characters rather than any single variable and microscopy of plant remains can result in reliable recognition of peatland-origin of sediment material when non-impacted sites are available for comparison. Dating of disturbed recent sediments is challenging. River-mouth areas with reservoir history can be particularly useful as the terrestrial soil strata provides a dated horizon under recent sediments.

The importance of pH and sand substrate in the revegetation of saline non-waterlogged peat fields.

PubMed

Montemayor, Marilou B; Price, Jonathan; Rochefort, Line

2015-11-01

A partially peat-extracted coastal bog contaminated by seawater was barren and required revegetation as a wetland. Peat fields were rectangular in shape, cambered in cross-section profile, and separated by drainage ditches. Common to all peat fields were symmetrical patterns in micro-topography with slopes between differences in elevation. Saline non-waterlogged slopes of ∼5% occurred as a symmetrical pair on each side of the crest of the cambered profile, at one end of each peat field. Three rows were laid across this slope (Top, Middle, and Bottom rows) and transplanted with naturally-growing plant species with their sand substrate, in three experiments, and grown for a year. In the Spartina pectinata experiment, bare root stem sections were also planted. Another experiment was conducted to determine changes in the characteristics of a volume of sand when incubated in saline peat fields. We found the salinity of peat increased with moisture downslope, and pH decreased with increase in salinity. S. pectinata grew best when planted with its sand substrate compared with bare root stem section, and when planted in Bottom rows. Juncus balticus had excellent growth in all rows. Unexpectedly, Festuca rubra that was inconspicuous beneath the J. balticus canopy in the natural donor site grew densely within the J. balticus sods. Agrostis stolonifera grew well but seemed to show intolerance to the surrounding acidic peat by curling up its stolons. The pH of the incubated sand volume was much higher than the surrounding peat. These studies suggest that recognition of plant niches and pH manipulation are important in the revegetation of disturbed Sphagnum peatlands that are found abundantly in the northern hemisphere. Results are also relevant to the reclamation of other disturbed lands. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cone Penetration Testing, a new approach to quantify coastal-deltaic land subsidence by peat consolidation

NASA Astrophysics Data System (ADS)

Koster, Kay; Erkens, Gilles; Zwanenburg, Cor

2016-04-01

It is undisputed that land subsidence threatens coastal-deltaic lowlands all over the world. Any loss of elevation (on top of sea level rise) increases flood risk in these lowlands, and differential subsidence may cause damage to infrastructure and constructions. Many of these settings embed substantial amounts of peat, which is, due to its mechanically weak organic composition, one of the main drivers of subsidence. Peat is very susceptible to volume reduction by loading and drainage induced consolidation, which dissipates pore water, resulting in a tighter packing of the organic components. Often, the current state of consolidation of peat embedded within coastal-deltaic subsidence hotspots (e.g. Venice lagoon, Mississippi delta, San Joaquin delta, Kalimantan peatlands), is somewhere between its initial (natural) and maximum compressed stage. Quantifying the current state regarding peat volume loss, is of utmost importance to predict potential (near) future subsidence when draining or loading an area. The processes of subsidence often afflict large areas (>103 km2), thus demanding large datasets to assess the current state of the subsurface. In contrast to data describing the vertical motions of the actual surface (geodesy, satellite imagery), subsurface information applicable for subsidence analysis are often lacking in subsiding deltas. This calls for new initiatives to bridge that gap. Here we introduce Cone Penetration Testing (CPT) to quantify the amount of volume loss peat layers embedded within the Holland coastal plain (the Netherlands) experienced. CPT measures soil mechanical strength, and hundreds of thousands of CPTs are conducted each year on all continents. We analyzed 28 coupled CPT-borehole observations, and found strong empirical relations between volume loss and increased peat mechanical strength. The peat lost between ~20 - 95% of its initial thickness by dissipation of excess pore water. An increase in 0.1 - 0.4 MPa of peat strength is accountable for 20 - 75 % of the volume loss, and 0.4 - 0.7 MPa for 75 - 95 % volume loss. This indicates that large amounts of volume by water dissipation has to be lost, before peat experiences a serious increase in strength, which subsequently continuous to increase with only small amount of volume loss. To demonstrate the robustness of our approach to the international field of land subsidence, we applied the obtained empirical relations to previously published CPT logs deriving from the peat-rich San Joaquin-Sacramento delta and the Kalimantan peatlands, and found volume losses that correspond with previously published results. Furthermore, we used the obtained results to predict maximum surface lowering for these areas by consolidation. In conclusion, these promising results and its worldwide popularity yielding large datasets, open the door for CPT as a generic method to contribute to quantifying the imminent threat of coastal-deltaic land subsidence.

Subsidence in tropical peatlands: Estimating CO2 fluxes from peatlands in Southeast Asia

NASA Astrophysics Data System (ADS)

Hoyt, A.; Harvey, C. F.; Seppalainen, S. S.; Chaussard, E.

2017-12-01

Tropical peatlands of Southeast Asia are an important global carbon stock. However, they are being rapidly deforested and drained. Peatland drainage facilitates peat decomposition, releases sequestered peat carbon to the atmosphere as CO2, and leads to subsidence of the peat surface. As a result, subsidence measurements can be used to monitor peatland carbon loss over time. Until now, subsidence measurements have been primarily limited to ground-based point measurements using subsidence poles. Here we demonstrate a powerful method to measure peatland subsidence rates across much larger areas than ever before. Using remotely sensed InSAR data, we map subsidence rates across thousands of square kilometers in Southeast Asia and validate our results against ground-based subsidence measurements. The method allows us to monitor subsidence in remote locations, providing unprecedented spatial information, and the first comprehensive survey of land uses such as degraded peatlands, burnt and open areas, shrub lands, and smallholder farmlands. Strong spatial patterns emerged, with the highest subsidence rates occurring at the centers of peat domes, where the peat is thickest and drainage depths are likely to be largest. Peatland subsidence rates were also strongly dependent on current and historical land use, with typical subsidence rates ranging from 2-4 cm/yr. Finally, we scaled up our results to calculate total annual emissions from peat decomposition in degraded peatlands.

Microbial Response in Peat Overlying Kimberlite Pipes in The Attawapiskat Area, Northern Ontario

NASA Astrophysics Data System (ADS)

Donkervoort, L. J.; Southam, G.

2009-05-01

Exploration for ore deposits occurring under thick, post-mineralized cover requires innovative methods and instrumentation [1]. Buried kimberlite pipes 'produce' geochemical conditions such as increased pH and decreased Eh in overlying peat [2] that intuitively select for bacterial populations that are best able to grow and, which in turn affect the geochemistry producing a linked signal. A microbiological study of peat was conducted over the Zulu kimberlite in the Attawapiskat area of the James Bay Lowlands to determine if the type of underlying rock influences the diversity and populations of microorganisms living in the overlying peat. Peat was sampled along an 800 m transect across the Zulu kimberlite, including samples underlain by limestone. Microbial populations and carbon source utilization patterns of peat samples were compared between the two underlying rock types. Results demonstrate an inverse relationship of increased anaerobic populations and lower biodiversity directly above the kimberlite pipe. These results support a reduced 'column' consistent with the model presented by Hamilton [3]. The combination of traditional bacterial enumeration and community- level profiling represents a cost-effective and efficient exploration technique that can serve to compliment both geophysical and geochemical surveys. [1] Goldberg (1998) J. Geochem. Explor. 61, 191-202 [2] Hattori and Hamilton (2008) Appl. Geochem. 23, 3767-3782 [3] Hamilton (1998) J. Geochem. Explor. 63, 155-172

Recent Measurements of Groundwater Recharge and Discharge Through Everglades' Peat Sediments Using Short-Lived Radium Isotopes

NASA Astrophysics Data System (ADS)

Krest, J. M.; Harvey, J. W.

2002-05-01

Peat sediments are present as a nearly continuous surface layer across large areas of the Everglades. These sediments have relatively low hydraulic conductivity, impeding water exchange between surface water and the underlying surficial aquifer. Although vertical water transport does occur across the peat layer, rates are slow enough that they are difficult to quantify. Even modest rates of vertical transport, however, become significant to water budgets and nutrient cycles when they occur over a large area. In the Everglades, common methods for measuring exchange across the peat layer are prone to complications: small hydraulic gradients are difficult to measure; seepage meters tend to be imprecise at slow rates; radon profiles or emanation rates are complicated by methane bubble ebullition; chloride profiles often exhibit a strong gradient only at the surface of the peat. We are employing a method that takes advantage of the different production rates of short-lived radium isotopes (Ra-223 and Ra-224) in the peat sediments and in the underlying sand or carbonate aquifer. Pore water radium concentrations are balanced by radioactive decay and production in the surrounding sediments. As the pore water is carried across the sediment interface a temporary excess or deficit of dissolved radium exists until decay is again balanced by the new production rate. We have derived steady-state, one-dimensional models to determine flow rates on the basis of this disequilibrium. This method has the advantage of being most sensitive at the base of the peat, away from transient perturbations occurring at the surface. In addition, Ra-223 and Ra-224 are collected simultaneously, providing two independent measurements. At present we have tested the method in Water Conservation Area-1 and WCA-2A, quantifying recharge and discharge on opposite sides of Levee 39, and also in more central sites in WCA-2A. Additional work is underway in Taylor Slough and Shark Slough.

Variable carbon losses from recurrent fires in drained tropical peatlands.

PubMed

Konecny, Kristina; Ballhorn, Uwe; Navratil, Peter; Jubanski, Juilson; Page, Susan E; Tansey, Kevin; Hooijer, Aljosja; Vernimmen, Ronald; Siegert, Florian

2016-04-01

Tropical peatland fires play a significant role in the context of global warming through emissions of substantial amounts of greenhouse gases. However, the state of knowledge on carbon loss from these fires is still poorly developed with few studies reporting the associated mass of peat consumed. Furthermore, spatial and temporal variations in burn depth have not been previously quantified. This study presents the first spatially explicit investigation of fire-driven tropical peat loss and its variability. An extensive airborne Light Detection and Ranging data set was used to develop a prefire peat surface modelling methodology, enabling the spatially differentiated quantification of burned area depth over the entire burned area. We observe a strong interdependence between burned area depth, fire frequency and distance to drainage canals. For the first time, we show that relative burned area depth decreases over the first four fire events and is constant thereafter. Based on our results, we revise existing peat and carbon loss estimates for recurrent fires in drained tropical peatlands. We suggest values for the dry mass of peat fuel consumed that are 206 t ha(-1) for initial fires, reducing to 115 t ha(-1) for second, 69 t ha(-1) for third and 23 t ha(-1) for successive fires, which are 58-7% of the current IPCC Tier 1 default value for all fires. In our study area, this results in carbon losses of 114, 64, 38 and 13 t C ha(-1) for first to fourth fires, respectively. Furthermore, we show that with increasing proximity to drainage canals both burned area depth and the probability of recurrent fires increase and present equations explaining burned area depth as a function of distance to drainage canal. This improved knowledge enables a more accurate approach to emissions accounting and will support IPCC Tier 2 reporting of fire emissions. © 2015 John Wiley & Sons Ltd.

Derivation of burn scar depths and estimation of carbon emissions with LIDAR in Indonesian peatlands

PubMed Central

Ballhorn, Uwe; Siegert, Florian; Mason, Mike; Limin, Suwido

2009-01-01

During the 1997/98 El Niño-induced drought peatland fires in Indonesia may have released 13–40% of the mean annual global carbon emissions from fossil fuels. One major unknown in current peatland emission estimations is how much peat is combusted by fire. Using a light detection and ranging data set acquired in Central Kalimantan, Borneo, in 2007, one year after the severe peatland fires of 2006, we determined an average burn scar depth of 0.33 ± 0.18 m. Based on this result and the burned area determined from satellite imagery, we estimate that within the 2.79 million hectare study area 49.15 ± 26.81 megatons of carbon were released during the 2006 El Niño episode. This represents 10–33% of all carbon emissions from transport for the European Community in the year 2006. These emissions, originating from a comparatively small area (approximately 13% of the Indonesian peatland area), underline the importance of peat fires in the context of green house gas emissions and global warming. In the past decade severe peat fires occurred during El Niño-induced droughts in 1997, 2002, 2004, 2006, and 2009. Currently, this important source of carbon emissions is not included in IPCC carbon accounting or in regional and global carbon emission models. Precise spatial measurements of peat combusted and potential avoided emissions in tropical peat swamp forests will also be required for future emission trading schemes in the framework of Reduced Emissions from Deforestation and Degradation in developing countries. PMID:19940252

Identification of runoff formation with two dyes in a mid-latitude mountain headwater

NASA Astrophysics Data System (ADS)

Vlček, Lukáš; Falátková, Kristýna; Schneider, Philipp

2017-06-01

Subsurface flow in peat bog areas and its role in the hydrologic cycle has garnered increased attention as water scarcity and floods have increased due to a changing climate. In order to further probe the mechanisms in peat bog areas and contextualize them at the catchment scale, this experimental study identifies runoff formation at two opposite hillslopes in a peaty mountain headwater; a slope with organic peat soils and a shallow phreatic zone (0.5 m below surface), and a slope with mineral Podzol soils and no detectable groundwater (> 2 m below surface). Similarities and differences in infiltration, percolation and preferential flow paths between both hillslopes could be identified by sprinkling experiments with Brilliant Blue and Fluorescein sodium. To our knowledge, this is the first time these two dyes have been compared in their ability to stain preferential flow paths in soils. Dye-stained soil profiles within and downstream of the sprinkling areas were excavated parallel (lateral profiles) and perpendicular (frontal profiles) to the slopes' gradients. That way preferential flow patterns in the soil could be clearly identified. The results show that biomat flow, shallow subsurface flow in the organic topsoil layer, occurred at both hillslopes; however, at the peat bog hillslope it was significantly more prominent. The dye solutions infiltrated into the soil and continued either as lateral subsurface pipe flow in the case of the peat bog, or percolated vertically towards the bedrock in the case of the Podzol. This study provides evidence that subsurface pipe flow, lateral preferential flow along decomposed tree roots or logs in the unsaturated zone, is a major runoff formation process at the peat bog hillslope and in the adjacent riparian zone.

Low ash, planar peat swamp development in an alluvial plain setting: The No. 5 block beds of southern West Virginia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Staub, J.R.; Richards, B.K.

1992-01-01

Coals from the No. 5 Block beds (Westphalian D) are noted for their low ash and sulfur content. Beds are multiple benched, with rock partings separating individual benches. Benches have limited continuity and, where thick are dominated by bright, high ash coal at the base and dull, low ash coal in their upper portions. The duller coals contain more exinite and inertinite group macerals than the brighter coals. The depositional setting is an alluvial plain environment with channel systems separated by distances of about 20 km. The channel systems were flanked by clastic swamps for distances of up to 7more » km or more on either side. Areas of flood plain most distant from the channels were sites where peat accumulated and these zones were about 8 km across. High energy, low frequency flood events introduced fine grained sediment into the peat swamps resulting in thin layers of sediment being deposited on top of the peat. These sediment layers are thicker in areas where the underlying coal is the thickest. These thick coal areas are topographically negative. This relationship between coal and parting thickness and topography indicates that these peat swamps were low-lying or planar. Individual coal benches contain abundant amounts of preserved cellular tissue (telocollinite, semifusinite, fusinite) at most locations indicating that woody arborescent like vegetation was widespread in the swamps suggesting a planar morphology. The high concentrations of exinite and inertinite group macerals found in the upper portions of individual benches resulted from decomposition and oxidation of the peat in subaerial to aquatic planar swamp environments.« less

Recent changes in vegetation, hydrotopography and peat accumulation in detailed case studies of northern aapa mires

NASA Astrophysics Data System (ADS)

Tahvanainen, Teemu; Kumpula, Timo; Tolonen, Kimmo

2016-04-01

Aapa mires are northern mire complexes with typical patterned central fen areas and relatively thin peat layers. In principle, aapa mires could develop into raised bogs either 1) through autogenic succession, given enough time for peat accumulation or 2) through allogenic mechanism triggered by hydrological change. Climate change models predict that the climatic envelop of aapa mires will move north and, indeed, that hydrology may change sufficiently to cause allogenic change pressure. Potential resilience or pace of ecosystem-scale responses are poorly understood, however, in the case of aapa mires. We studied recent (ca. 60 years) changes in vegetation, hydrotopography and peat accumulation of two aapa mires at their southern limit of distribution in eastern Finland. We used repeated sampling after 60 years combined with peat stratigraphy and time-series of aerial images in a multi-proxy approach. The study site at the Valkeasuo mire was affected by extensive drainage activities in its catchment, while the aapa mire area itself was not drained. This resulted in the loss of minerotrophic hydrology that lead to rapid changes over the whole patterned fen area. Wet minerotrophic sedge fen vegetation was almost totally covered by ombrotrophic Sphagnum mosses within few decades. Even up to 50 cm high hummocks emerged on the patterned fen strings in an abrupt response that could be precisely dated by simultaneous encroachment of pine seedlings and from the aerial images. The recent apparent rate of carbon accumulation of the new Sphagnum peat was ca. 100 g m-2 -a. The other study site in the Ilajansuo aapa mire persists in a more pristine setting without significant disturbance in its catchment area. Here the mineral-water limit was studied across a transition between a bog zone and an aapa mire zone of the mire complex. We were able to exactly locate a 100 x 300-m special study area and repeat e.g. mapping of all trees, of all topographic patterns (hummocks, hollows, pools), 155 peat depth measurements and 38 vegetation plots. Despite the pristine wilderness character of the site, we found increased tree encroachment, significant increase of height of Sphagnum hummocks, lateral expansion of ombrotrophic bog zone over fen vegetation and increase of dwarf-shrubs typical to raised bog vegetation. Peat thickness in the bog zone had increased by 2.2 mm per year, greatly exceeding the long-term average of bogs in the region. Our case studies demonstrate a remarkable potential of ecosystem-scale responses in northern aapa mires, ecotone mire type between temperate-south boreal bogs and subarctic palsa mires. Hydrological disturbances can rapidly trigger an allogenic mechanism of fen to bog transition. Traces of ongoing changes in aapa mires can be apparent also in seemingly pristine sites when accurate repeated measurements are performed. Although the observed changes may threaten aapa mire habitat types and biota, they are progressive in terms of peat growth and carbon dioxide sequestration.

Nitrogen and phosphorus loading from drained wetlands adjacent to Upper Klamath and Agency lakes, Oregon

USGS Publications Warehouse

Snyder, Daniel T.; Morace, Jennifer L.

1997-01-01

The results of this study could be useful in helping to prioritize which drained wetlands may provide the greatest benefits with regard to reducing nutrient loads to the lake if restoration or land-use modifications are instituted. Recent acquisition and planned restoration of drained wetland areas at the Wood River and Williamson River North properties may produce significant reduction in the quantity of nutrients released by the decomposition of peat soils of these areas. If the water table rises to predrainage levels, the peats soils may become inundated most of the year, resulting in the continued long-term storage of nutrients within the peat soils by reducing aerobic decomposition. The maximum benefit, in terms of decreasing potential nutrient loss due to peat decomposition, could be the reduction of total nitrogen and total phosphorus loss to about one-half that of the 1994–95 annual loss estimated for all the drained wetlands sampled for this study.

Peat Depth Assessment Using Airborne Geophysical Data for Carbon Stock Modelling

NASA Astrophysics Data System (ADS)

Keaney, Antoinette; McKinley, Jennifer; Ruffell, Alastair; Robinson, Martin; Graham, Conor; Hodgson, Jim; Desissa, Mohammednur

2013-04-01

The Kyoto Agreement demands that all signatory countries have an inventory of their carbon stock, plus possible future changes to this store. This is particularly important for Ireland, where some 16% of the surface is covered by peat bog. Estimates of soil carbon stores are a key component of the required annual returns made by the Irish and UK governments to the Intergovernmental Panel on Climate Change. Saturated peat attenuates gamma-radiation from underlying rocks. This effect can be used to estimate the thickness of peat, within certain limits. This project examines this relationship between peat depth and gamma-radiation using airborne geophysical data generated by the Tellus Survey and newly acquired data collected as part of the EU-funded Tellus Border project, together encompassing Northern Ireland and the border area of the Republic of Ireland. Selected peat bog sites are used to ground truth and evaluate the use of airborne geophysical (radiometric and electromagnetic) data and validate modelled estimates of soil carbon, peat volume and depth to bedrock. Data from two test line sites are presented: one in Bundoran, County Donegal and a second line in Sliabh Beagh, County Monaghan. The plane flew over these areas at different times of the year and at a series of different elevations allowing the data to be assessed temporally with different soil/peat saturation levels. On the ground these flight test lines cover varying surface land use zones allowing future extrapolation of data from the sites. This research applies spatial statistical techniques, including uncertainty estimation in geostatistical prediction and simulation, to investigate and model the use of airborne geophysical data to examine the relationship between reduced radioactivity and peat depth. Ground truthing at test line locations and selected peat bog sites involves use of ground penetrating radar, terrestrial LiDAR, peat depth probing, magnetometry, resistivity, handheld gamma-ray spectrometry, moisture content and rainfall monitoring combined with a real-time Differential Global Positioning System (DGPS) to monitor temporal and spatial variability of bog elevations. This research will assist in determining the accuracy and limitations of modelling soil carbon and changes in peat stocks by investigating the attenuation of gamma-radiation from underlying rocks. Tellus Border is supported by the EU INTERREG IVA programme, which is managed by the Special EU Programmes Body in Northern Ireland, the border Region of Ireland and western Scotland. The Tellus project was funded by the Northern Ireland Development of Enterprise Trade and Investment and by the Rural Development Programme through the Northern Ireland Programme for Building Sustainable Prosperity.

Isotopic anomalies of H2 and C in the peat from the Tunguska meteorite impact area

NASA Astrophysics Data System (ADS)

Kolesnikov, E. M.

Core samples of peat collected at the site of the Tunguska meteorite impact were mixed with CuO and burned inside evacuated and sealed quartz ampules. As a result, the organic components of peat were transformed to H2O and CO2 which were then separated and analyzed using a mass spectrometer. Results show that layers located above the level dated by 1908 are characterized by lighter H2 isotopes and heavier C isotopes, compared with lower layers. These effects are ascribed to the conservation and gradual redistribution of cosmic matter (e.g., regular chondrites, achondrites, and C4-type carbon chondrites) in the upper peat layers.

Changes in the geodiversity of Dutch peatlands inferred from 19th and 20th century landscape paintings

NASA Astrophysics Data System (ADS)

Jungerius, Pieter Dirk; van den Ancker, Hanneke; Wevers, Nina

2013-04-01

Geodiversity is the natural and cultural range of geological, geomorphological and soil features. We analysed the large database of 19th and early 20th century paintings of Simonis and Buunk (www.Simonis-Buunk.com) to track changes in the geodiversity of Dutch peatlands since pre-photographic times. Peat dominated in two of the eight main landscapes of the Netherlands: the Lowland peats in the Holocene west and the Highland peats in the sandy Pleistocene eastern parts. Painters were mainly attracted by the lowland peats. Since more than thousand years, peat plays a major role in Dutch military security, economy, ecology and cultural life. Natural variety and cultural use resulted in a geodiversity that is unique in Europe. There are more than 100 place names with 'veen' (= peat), and surnames with 'veen' are common. Proof of the exploitation of peat for salt and fuel exists from the Roman times onwards. In the 9th century, peatlands were drained and reclaimed for growing wheat. Already in the 11th century, it was necessary to build dikes to prevent flooding, to control waterlevels to avoid further oxidation, and to convert landuse to grassland. But subsidence continued, and in the 14th century windmills were needed to drain the lands and pump the water out. In the 16th century industrial peat exploitation fuelled the rise of industries and cities. All this draining and digging caused the peat surface to shrink. The few remaining living peats are conserved by nature organisations. Geodiversity and landscape paintings In the peat landscapes, popular painting motives were high water levels, the grasslands of the 'Green Heart', the winding streams and remaining lakes. The paintings of landscapes where peat had been removed, show watermanagement adaptations: wind mills, different water levels, canals made for the transport of fuel, bridges, tow paths and the 'plassen', i.e. the lakes left after peat exploitation. The droogmakerijen (reclaimed lakes), now 2 to 5 m below sealevel, were less inspiring. Examples of geodiversity changes illustrated by the landscape paintings • Peat extraction stopped • Land use changed e.g. the deforestation of the 'Bovenlanden' • Erosion by waves and boats caused the collapse of peat islands in the artificial lakes • Peat polders of the Green Heart were sacrificed for building projects • 90% of the original wind mills were replaced by electrical and motor pumps • Horse traction was replaced by motor vehicles, which made tow paths and high wooden bridges redundant. • Dam burst risk increased and skating scenes disappeared with climate change, References Jungerius, P.D., 2010. Sea level rise and the response of the Dutch people - Adaptive strategies based on geomorphologic principles give sustainable solutions. In: Martini I.P.& Chesworth, W.(eds.) Landscapes and Societies. Springer Verlag.

Citrus compost and its water extract for cultivation of melon plants in greenhouse nurseries. Evaluation of nutriactive and biocontrol effects.

PubMed

Bernal-Vicente, A; Ros, M; Tittarelli, F; Intrigliolo, F; Pascual, J A

2008-12-01

Two different types of citrus composts, and their water extracts, were tested with regard to their utilisations as partial substitutes for peat in growing media for melon seedlings in greenhouse nurseries. Both compost showed higher plant growth than peat. Compost composed by citrus waste and green residue (C2) showed greater plant growth than compost obtained from the same organic matrices mentioned above further the addition of sludge obtained from citrus industry (C1). Compost C2 showed a greater auxinic effect than C1 and it was the only one that showed cytokinic effect. Both composts also demonstrated a biocontrol effect against Fusarium oxysporum for melon plants: the effects were also higher in C2 than in C1. Higher number of isolated fungi was active against F. oxysporum in compost C2, than compost C1. No different bacterial biocontrol efficacy was observed between both composts. The water extracts of both composts gave lower plant yields than their solid matrices, their relative effects being similar to those of the solid composts (C2 extract gave higher plant yields than the extract from C1). The biocontrol effects of compost water extracts followed the same trend.

Health burden from peat wildfire in North Carolina

EPA Science Inventory

In June 2008, a wildfire smoldering through rich peat deposits in the Pocosin Lakes National Wildlife Refuge produced massive amounts of smoke and exposed a largely rural North Carolina area to air pollution in access of the National Ambient Air Quality Standards. In this talk, w...

Sorption of selected organic compounds from water to a peat soil and its humic-acid and humin fractions: Potential sources of the sorption nonlinearity

USGS Publications Warehouse

Chiou, C.T.; Kile, D.E.; Rutherford, D.W.; Sheng, G.; Boyd, S.A.

2000-01-01

The sorption isotherms of ethylene dibromide (EDB), diuron (DUN), and 3,5-dichlorophenol (DCP) from water on the humic acid and humin fractions of a peat soil and on the humic-acid of a muck soil have been measured. The data were compared with those of the solutes with the whole peat from which the humic-acid (HA) and humin (HM) fractions were derived and on which the sorption of the solutes exhibited varying extents of nonlinear capacities at low relative concentrations (C(e)/S(w)). The HA fraction as prepared by the density-fractionated method is relatively pure and presumably free of high- surface-area carbonaceous material (HSACM) that is considered to be responsible for the observed nonlinear sorption for nonpolar solutes (e.g., EDB) on the peat; conversely, the base-insoluble HM fraction as prepared is presumed to be enriched with HSACM, as manifested by the greatly higher BET- (N2) surface area than that of the whole peat. The sorption of EDB on HA exhibits no visible nonlinear effect, whereas the sorption on HM shows an enhanced nonlinearity over that on the whole peat. The sorption of polar DUN and DCP on HA and HM display nonlinear effects comparable with those on the whole peat; the effects are much more significant than those with nonpolar EDB. These results conform to the hypothesis that adsorption onto a small amount of strongly adsorbing HSACM is largely responsible for the nonlinear sorption of nonpolar solutes on soils and that additional specific interactions with the active groups of soil organic matter are responsible for the generally higher nonlinear sorption of the polar solutes.

From carbon sink to carbon source: extensive peat oxidation in insular Southeast Asia since 1990

NASA Astrophysics Data System (ADS)

Miettinen, Jukka; Hooijer, Aljosja; Vernimmen, Ronald; Liew, Soo Chin; Page, Susan E.

2017-02-01

Tropical peatlands of the western part of insular Southeast Asia have experienced extensive land cover changes since 1990. Typically involving drainage, these land cover changes have resulted in increased peat oxidation in the upper peat profile. In this paper we provide current (2015) and cumulative carbon emissions estimates since 1990 from peat oxidation in Peninsular Malaysia, Sumatra and Borneo, utilizing newly published peatland land cover information and the recently agreed Intergovernmental Panel on Climate Change (IPCC) peat oxidation emission values for tropical peatland areas. Our results highlight the change of one of the Earth’s most efficient long-term carbon sinks to a short-term emission source, with cumulative carbon emissions since 1990 estimated to have been in the order of 2.5 Gt C. Current (2015) levels of emissions are estimated at around 146 Mt C yr-1, with a range of 132-159 Mt C yr-1 depending on the selection of emissions factors for different land cover types. 44% (or 64 Mt C yr-1) of the emissions come from industrial plantations (mainly oil palm and Acacia pulpwood), followed by 34% (49 Mt C yr-1) of emissions from small-holder areas. Thus, altogether 78% of current peat oxidation emissions come from managed land cover types. Although based on the latest information, these estimates may still include considerable, yet currently unquantifiable, uncertainties (e.g. due to uncertainties in the extent of peatlands and drainage networks) which need to be focused on in future research. In comparison, fire induced carbon dioxide emissions over the past ten years for the entire equatorial Southeast Asia region have been estimated to average 122 Mt C yr-1 (www.globalfiredata.org/_index.html). The results emphasise that whilst reducing emissions from peat fires is important, urgent efforts are also needed to mitigate the constantly high level of emissions arising from peat drainage, regardless of fire occurrence.

Nitrosation and nitration of fulvic acid, peat and coal with nitric acid

USGS Publications Warehouse

Thorn, Kevin A.; Cox, Larry G.

2016-01-01

Nitrohumic acids, produced from base extraction of coals and peats oxidized with nitric acid, have received considerable attention as soil ammendments in agriculture. The nitration chemistry however is incompletely understood. Moreover, there is a need to understand the reaction of nitric acid with natural organic matter (NOM) in general, in the context of a variety of environmental and biogeochemical processes. Suwannee River NOM, Suwannee River fulvic acid, and Pahokee Peat fulvic acid were treated with 15N-labeled nitric acid at concentrations ranging from 15% to 22% and analyzed by liquid and solid state 15N NMR spectroscopy. Bulk Pahokee peat and Illinois #6 coal were also treated with nitric acid, at 29% and 40% respectively, and analyzed by solid state 15N NMR spectroscopy. In addition to nitro groups from nitration of aromatic carbon, the 15N NMR spectra of all five samples exhibited peaks attributable to nitrosation reactions. These include nitrosophenol peaks in the peat fulvic acid and Suwannee River samples, from nitrosation of phenolic rings, and N-nitroso groups in the peat samples, from nitrosation of secondary amides or amines, the latter consistent with the peat samples having the highest naturally abundant nitrogen contents. Peaks attributable to Beckmann and secondary reactions of the initially formed oximes were present in all spectra, including primary amide, secondary amide, lactam, and nitrile nitrogens. The degree of secondary reaction product formation resulting from nitrosation reactions appeared to correlate inversely with the 13C aromaticities of the samples. The nitrosation reactions are most plausibly effected by nitrous acid formed from the reduction of nitric acid by oxidizable substrates in the NOM and coal samples.

Nitrosation and Nitration of Fulvic Acid, Peat and Coal with Nitric Acid

PubMed Central

Thorn, Kevin A.; Cox, Larry G.

2016-01-01

Nitrohumic acids, produced from base extraction of coals and peats oxidized with nitric acid, have received considerable attention as soil ammendments in agriculture. The nitration chemistry however is incompletely understood. Moreover, there is a need to understand the reaction of nitric acid with natural organic matter (NOM) in general, in the context of a variety of environmental and biogeochemical processes. Suwannee River NOM, Suwannee River fulvic acid, and Pahokee Peat fulvic acid were treated with 15N-labeled nitric acid at concentrations ranging from 15% to 22% and analyzed by liquid and solid state 15N NMR spectroscopy. Bulk Pahokee peat and Illinois #6 coal were also treated with nitric acid, at 29% and 40% respectively, and analyzed by solid state 15N NMR spectroscopy. In addition to nitro groups from nitration of aromatic carbon, the 15N NMR spectra of all five samples exhibited peaks attributable to nitrosation reactions. These include nitrosophenol peaks in the peat fulvic acid and Suwannee River samples, from nitrosation of phenolic rings, and N-nitroso groups in the peat samples, from nitrosation of secondary amides or amines, the latter consistent with the peat samples having the highest naturally abundant nitrogen contents. Peaks attributable to Beckmann and secondary reactions of the initially formed oximes were present in all spectra, including primary amide, secondary amide, lactam, and nitrile nitrogens. The degree of secondary reaction product formation resulting from nitrosation reactions appeared to correlate inversely with the 13C aromaticities of the samples. The nitrosation reactions are most plausibly effected by nitrous acid formed from the reduction of nitric acid by oxidizable substrates in the NOM and coal samples. PMID:27175784

Conservation of peat soils in agricultural use by infiltration of ditch water via submerged drains: results of a case study in the western peat soil area of The Netherlands

NASA Astrophysics Data System (ADS)

van den Akker, Jan J. H.; Hendriks, Rob F. A.

2017-04-01

About 8% of all soils in The Netherlands are peat soils which almost all drained with ditches and mainly in agricultural use as permanent pasture for dairy farming. The largest part of the peat meadow area is situated in the densely populated western provinces South- and North-Holland and Utrecht and is called the Green Heart and is valued as a historic open landscape. Conservation of these peats soil by raising water levels and converting the peat meadow areas mainly in very extensive grasslands or wet nature proved to be a very costly and slow process due to the strong opposition of farmers and many others who value the open cultural historic landscape and meadow birds. The use of submerged drains seems to be a promising solution acceptable for dairy farmers and effective in diminishing peat oxidation and so the associated subsidence and CO2 emissions. Oxidation of peat soils strongly depends on the depth of groundwater levels in dry periods. In dry periods the groundwater level can be 30 to 50 cm lower than the ditchwater level, which is 30 - 60 cm below soil surface. Infiltration of ditchwater via submerged drain can raise the groundwater level up to the ditchwater level and diminish the oxidation and associated subsidence and CO2 emissions with at least 50%. Since 2003 several pilots with submerged drains are started to check this theoretical reduction and to answer questions raised about water usage and water quality and grass yields and trafficability etcetera. In our presentation we focus on the results of a pilot in South-Holland concerning the hydrological aspects, however, include results from the other pilots to consider the long term aspects such as the reduction of subsidence. The use of submerged drains proves to be promising to reduce peat oxidation and so subsidence and CO2 emissions with at least 50%. Grass yields are more or less equal in parcels with versus parcels without submerged drains. Trafficability in wet periods is better and trampling less by the draining effect of submerged drains. This reduces losses of grass yield by trampling and increases the length of the grazing season. The use of submerged drains causes a higher water usage, however, raising ditchwater levels to derive the same peat soil conservation would require a higher amount of inlet water. The impact on ditchwater quality is in most cases positive, however, sometimes slightly negative. For the dairy farmer submerged drains are economically in the short term not effective, however in the longer term increasingly positive. For the society as a whole the use of submerged drains is a very cost effective way to reduce CO2 emissions and subsidence of peat soils in agricultural use.

Heterotrophic respiration in drained tropical peat temperatures influenced by shading gradient

NASA Astrophysics Data System (ADS)

Jauhiainen, Jyrki; Kerojoki, Otto; Silvennoinen, Hanna; Limin, Suwido; Vasander, Harri

2015-04-01

Lowland peatlands in Southeast Asia constitute a highly concentrated carbon (C) pool of global significance. These peatlands have formed over periods of several millennia by forest vegetation tolerant to flooding and poor substrates. Uncontrollable drainage and reoccurring wild fires in lack of management after removal of forest cover has impaired the C-storing functions in large reclaimed areas. Intergovernmental Panel on Climate Change (IPCC) reporting sees drained tropical organic soils as one of the largest greenhouse gas emissions releasing terrestrial systems. Vast areas of deforested tropical peatlands do not receive noteworthy shading by vegetation, which increases the amount of solar radiation reaching the peat surface. We studied heterotrophic carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) fluxes in tropical peat in conditions, where; (i) peat temperatures were modified by artificial shading (no shade, 28%, 51% and 90% from the full sun exposure), (ii) root respiration was minimized, (iii) nutrient availability for peat decomposer community was changed (NPK fertilization of 0 and 313 kg ha-1). The experiment was repeated at two over 20 years ago drained fallow agricultural- and degraded sites in Central Kalimantan, Indonesia. Enhanced shading created a lasting decrease in peat temperatures, and decreased diurnal temperature fluctuations, in comparison to less shaded plots. The largest peat temperature difference was between the unshaded and 90% shaded peat surface, where the average temperatures within the topmost 50-cm peat profile differed 3 °C, and diurnal temperatures at 5 cm depth varied up to 4.2 °C in the unshaded and 0.4 °C in the 90% shaded conditions. Highest impacts on the heterotrophic CO2 fluxes caused by the treatments were on agricultural land, where 90% shading from the full exposure resulted in a 33% lower CO2 emission average on the unfertilised plots and a 66% lower emission average on the fertilised plots. Correlation between peat temperature and CO2 flux suggested an approximately 8% (unfertilised) and 25% (fertilised) emissions change for each 1 °C temperature change at 5 cm depth on the agricultural land. CO2 flux responses to the treatments remained low or were inconsistent over the peat temperature range.. Fertilised conditions negatively correlated with N2O efflux with increases in temperature, suggesting a 12-36% lower efflux for each 1 °C increase in peat temperature (at 5 cm depth) at the sites. Despite the apparently similar landscapes of fallow agricultural land and degraded peatland sites, the differences in greenhouse gas dynamics are expected to be an outcome of the long-term management differences. Based on the results it is possible to seek management practices that prolong timespan for using drained tropical peat for cultivation, simultaneously reduce negative climate impacts created from peat substrate carbon loss, and also improve greenhouse gas monitoring techniques at field.

Tracing of ca 800 yr old mining activity in peat bog using Pb elemental concentrations and isotope compositions.

NASA Astrophysics Data System (ADS)

Baron, S.; Carignan, J.; Ploquin, A.

2003-04-01

Sixty sites of slags have been documented on the Mont-Lozère in southern France. The petrographic analysis shows that slags are metallurgical wastes (800 to 850 yr BP) which certainly result from smelting activity for lead and silver extraction (Ploquin et al., 2001). The aims of this study are: 1) to trace the source of Pb ores which supplied the smelting sites, by using the Pb isotopic composition of several surrounding Pb deposits, 2) to evaluate the actual pollution caused by these slags, by using elemental and isotopic compositions of soils, water and vegetation, and 3) to document the pollution history of the region, by using elemental and isotopic compositions of peat bog cores collected in the neighbourhood of the historical smelting sites. The lead isotopic composition of galena collected in most surrounding ores is very similar to that of different slag samples. On the other hand, the high precision of the results allowed us to select the mineralised areas which were probably the ore sources. The Pb isotopic composition of slags is even more homogeneous: 208/206 Pb: 2.092±0.002; 206/207 Pb: 1.179±0.001; 208/204 Pb: 38.663±0.025; 207/204 Pb: 15.665±0.006; 206/204 Pb: 18.476±0.023, and will allow source tracing in the environment. The "Narses Mortes" peat bog, around which two smelting sites have been reported, is strongly minerotrophic and contains 8 to 60% ash. A 1.40 m core have been retrieved and divided into 58 individual samples. Minerotrophic peat bog records both atmospheric deposition, soils leaching and the grounwater influence. The measured metal concentrations are normalised to Al contents of peat bog samples and the metal/Al ratios are compared to that of the Mont-Lozère granite: relative excess in metal concentrations are found in peat bog samples. An increasing excess of most metals (Pb, Zn, Cd...) was measured for surface samples, from 55 cm depth to the top of the core (23 cm depth). This profil might be attributed to atmospheric input during the last centuries. Pb and As alone are also enriched in some deeper samples (between 120--90 cm depth). At the moment, no sedimentation rates are available for this section of the peat bog. However, according to palynological data (de Beaulieu, in progress), the bottom of the core might be as old as 5000 years BP. This would place the medieval activities at the base of the surface metal enrichment (˜55 cm depth), having no large effect in Pb concentrations measured in peat bog. The older Pb-As enrichment remain enigmatic and may correspond to earlier anthropogenic activities (2000--2500 BP), a period for which very few traces of metallurgical activities are found in Occidental Europe. 14C dating and Pb isotope works are going on peat bog samples trying to discriminate metals sources.

Post-fire fluxes and sources of carbon in previously burnt tropical swamp peatlands, Brunei

NASA Astrophysics Data System (ADS)

Lupascu, M.; Akhtar, H.; Smith, T. E. L.; Sukmaria binti Hj Sukri, R.

2017-12-01

Tropical peatlands hold about 15-19% of the global organic carbon (C) pool of which 77% in Southeast Asia. Nonetheless Southeast Asian peatlands have been exploited for timber and land for agriculture leading to rapid deforestation, extensive drainage and frequent fires. Direct C-emissions through peat combustion must be quantified to examine the impact of peat fires on global and regional C-budgets, however it is also essential to evaluate oxidative decomposition of peat after fires for a complete understanding of ecosystem-scale fire impact. This kind of investigation is necessary also to understand the effect of peat burning on peat decomposition, because burning effects on the belowground environment are variable, depending on burnt frequency and fire severity. After a fire, ecosystems act as a C-source for months-to-years as ecosystem-respiration (Reco) exceeds photosynthesis. Furthermore during fires, the surface peat with a higher proportion of the more modern rapidly-cycled C burns preferentially. The loss of the surface peat possibly can reduce oxidative soil CO2 emissions, as the deeper, older peat, has more recalcitrant compounds. However, CO2emissions from this old C pool are a net flux to the atmosphere compared to the modern C. Within this context, we are quantifying the magnitudes and patterns of ecosystem-atmosphere fluxes of carbon dioxide (CO2) and methane (CH4) through cavity-ring spectroscopy in different transects of an intact tropical peat swamp forest and in two degraded forest areas affected by two and six fires over the last 40 years in Brunei, on the island of Borneo. We are using natural tracers such as δ13C and 14C to investigate the age and sources (auto- and heterotrophic) of C contributing to Reco and we are continuously monitoring soil temperature and water table level. Preliminary data show a similar magnitude of CO2 efflux between the intact (5.3 µmol CO2 m-2 s-1) and burnt areas (6.4 µmol CO2 m-2 s-1), with higher soil temperature in the latter. Our results will give a deeper insight into the vulnerability of the C pool in tropical peat swamp forest after fire events and aim at improving terrestrial soil C budget.

Greenhouse gas efflux from an impacted Malaysian tropical peat swamp (Invited)

NASA Astrophysics Data System (ADS)

Waldron, S.; Vihermaa, L. E.; Evers, S.; Garnett, M.; Newton, J.; Padfield, R.

2013-12-01

Tropical peatlands constitute ~11% of global peatland area and ~12% of the global peat C pool. Malaysia alone contains 10% of tropical peats. Due to rising global demands for food and biofuels, SE-Asia peat swamp forest ecosystems are threatened by increasing amounts of drainage, fire and conversion to plantation. These processes can change the GHG emissions and thus net ecosystem C balance. However, in comparison to temperate and boreal peatlands, there is a lack of data on terrestrial-aquatic-atmospheric carbon transfer from tropical peatlands, both those that are little disturbed and those facing anthropogenic pressures. Lateral transport of soil-respired carbon, and fluvial respiration or UV-oxidation of terrestrial DOC primes atmospheric carbon dioxide efflux. We now know that DOC lost from disturbed tropical peat swamp forests can be centuries to millennia old and originates deep within the peat column - this carbon may fuel efflux of old carbon dioxide and so anthropogenic land-use change renders the older, slower carbon cycles shorter and faster. Currently we have no knowledge of how significant ';older-slower' terrestrial-aquatic-atmospheric cycles are in disturbed tropical peatlands. Further, in some areas for commercial reasons, or by conservation bodies trying to minimise peat habitat loss, logged peats have been left to regenerate. Consequently, unpicking the legacy of multiple land uses on magnitude, age and source of GHG emissions is challenging but required to support land management decisions and projections of response to a changing climate. Here, we present the results of our first field campaign in July 2013 to the Raja Musa and Sungai Karang Peat Swamp Forest Reserves in North Selangor, Malaysia. This is one of Malaysia's largest oceanic peat swamps, and has been selectively logged and drained for 80 years, but is now subject to a 30 year logging ban to aid forest regeneration and build up wood stocks. From sites subject to different land use, we will present measurements of i) spatial variation in fluvial carbon dioxide and methane concentrations and associated efflux rates, and ii) the stable carbon isotopic composition of DIC and novel determination of the age of the effluxed carbon dioxide. From this we can consider if younger-faster or older-slower carbon cycling dominates the terrestrial-aquatic-atmospheric C transfer during this dry period sampling.

Geophysical surveying in the Sacramento Delta for earthquake hazard assessment and measurement of peat thickness

NASA Astrophysics Data System (ADS)

Craig, M. S.; Kundariya, N.; Hayashi, K.; Srinivas, A.; Burnham, M.; Oikawa, P.

2017-12-01

Near surface geophysical surveys were conducted in the Sacramento-San Joaquin Delta for earthquake hazard assessment and to provide estimates of peat thickness for use in carbon models. Delta islands have experienced 3-8 meters of subsidence during the past century due to oxidation and compaction of peat. Projected sea level rise over the next century will contribute to an ongoing landward shift of the freshwater-saltwater interface, and increase the risk of flooding due to levee failure or overtopping. Seismic shear wave velocity (VS) was measured in the upper 30 meters to determine Uniform Building Code (UBC)/ National Earthquake Hazard Reduction Program (NEHRP) site class. Both seismic and ground penetrating radar (GPR) methods were employed to estimate peat thickness. Seismic surface wave surveys were conducted at eight sites on three islands and GPR surveys were conducted at two of the sites. Combined with sites surveyed in 2015, the new work brings the total number of sites surveyed in the Delta to twenty.Soil boreholes were made at several locations using a hand auger, and peat thickness ranged from 2.1 to 5.5 meters. Seismic surveys were conducted using the multichannel analysis of surface wave (MASW) method and the microtremor array method (MAM). On Bouldin Island, VS of the surficial peat layer was 32 m/s at a site with pure peat and 63 m/s at a site peat with higher clay and silt content. Velocities at these sites reached a similar value, about 125 m/s, at a depth of 10 m. GPR surveys were performed at two sites on Sherman Island using 100 MHz antennas, and indicated the base of the peat layer at a depth of about 4 meters, consistent with nearby auger holes.The results of this work include VS depth profiles and UBC/NEHRP site classifications. Seismic and GPR methods may be used in a complementary fashion to estimate peat thickness. The seismic surface wave method is a relatively robust method and more effective than GPR in many areas with high clay content or where surface sediments have been disturbed by human activities. GPR does however provide significantly higher resolution and better depth control in areas with suitable recording conditions.

An appraisal of Indonesia's immense peat carbon stock using national peatland maps: uncertainties and potential losses from conversion.

PubMed

Warren, Matthew; Hergoualc'h, Kristell; Kauffman, J Boone; Murdiyarso, Daniel; Kolka, Randall

2017-12-01

A large proportion of the world's tropical peatlands occur in Indonesia where rapid conversion and associated losses of carbon, biodiversity and ecosystem services have brought peatland management to the forefront of Indonesia's climate mitigation efforts. We evaluated peat volume from two commonly referenced maps of peat distribution and depth published by Wetlands International (WI) and the Indonesian Ministry of Agriculture (MoA), and used regionally specific values of carbon density to calculate carbon stocks. Peatland extent and volume published in the MoA maps are lower than those in the WI maps, resulting in lower estimates of carbon storage. We estimate Indonesia's total peat carbon store to be within 13.6 GtC (the low MoA map estimate) and 40.5 GtC (the high WI map estimate) with a best estimate of 28.1 GtC: the midpoint of medium carbon stock estimates derived from WI (30.8 GtC) and MoA (25.3 GtC) maps. This estimate is about half of previous assessments which used an assumed average value of peat thickness for all Indonesian peatlands, and revises the current global tropical peat carbon pool to 75 GtC. Yet, these results do not diminish the significance of Indonesia's peatlands, which store an estimated 30% more carbon than the biomass of all Indonesian forests. The largest discrepancy between maps is for the Papua province, which accounts for 62-71% of the overall differences in peat area, volume and carbon storage. According to the MoA map, 80% of Indonesian peatlands are <300 cm thick and thus vulnerable to conversion outside of protected areas according to environmental regulations. The carbon contained in these shallower peatlands is conservatively estimated to be 10.6 GtC, equivalent to 42% of Indonesia's total peat carbon and about 12 years of global emissions from land use change at current rates. Considering the high uncertainties in peatland extent, volume and carbon storage revealed in this assessment of current maps, a systematic revision of Indonesia's peat maps to produce a single geospatial reference that is universally accepted would improve national peat carbon storage estimates and greatly benefit carbon cycle research, land use management and spatial planning.

Peatlands and potatoes; organic wetland soils in Uganda

NASA Astrophysics Data System (ADS)

Farmer, Jenny; Langan, Charlie; Gimona, Alessandro; Poggio, Laura; Smith, Jo

2017-04-01

Land use change in Uganda's wetlands has received very little research attention. Peat soils dominate the papyrus wetlands of the south west of the country, but the areas they are found in have been increasingly converted to potato cultivation. Our research in Uganda set out to (a) document both the annual use of and changes to these soils under potato cultivation, and (b) the extent and condition of these soils across wetland systems. During our research we found it was necessary to develop locally appropriate protocols for sampling and analysis of soil characteristics, based on field conditions and locally available resources. Over the period of one year we studied the use of the peat soil for potato cultivation by smallholder farmers in Ruhuma wetland and measured changes to surface peat properties and soil nutrients in fields over that time. Farmer's use of the fields changed over the year, with cultivation, harvesting and fallow periods, which impacted on soil micro-topography. Measured soil properties changed over the course of the year as a result of the land use, with bulk density, nitrogen content, potassium and magnesium all reducing. Comparison of changes in soil carbon stocks over the study period were difficult to make as it was not possible to reach the bottom of the peat layer. However, a layer of fallow weeds discarded onto the soil prior to preparation of the raised potato beds provided a time marker which gave insight into carbon losses over the year. To determine the peatland extent, a spatial survey was conducted in the Kanyabaha-Rushebeya wetland system, capturing peat depths and key soil properties (bulk density, organic matter and carbon contents). Generalised additive models were used to map peat depth and soil characteristics across the system, and maps were developed for these as well as drainage and land use classes. Comparison of peat cores between the two study areas indicates spatial variability in peat depths and the influence of neighbouring mineral soil hillslopes. Our work provides valuable insight into the condition and use of these tropical peat soils, which are under-researched yet highly depended upon by local communities, with wider climate impacts. Cultivation of these peat soils has implications for their future sustainability and use, and having insight into the impacts of land management on these soils improves local and national level capacity for better soil management.

Age, extent and carbon storage of the central Congo Basin peatland complex.

PubMed

Dargie, Greta C; Lewis, Simon L; Lawson, Ian T; Mitchard, Edward T A; Page, Susan E; Bocko, Yannick E; Ifo, Suspense A

2017-02-02

Peatlands are carbon-rich ecosystems that cover just three per cent of Earth's land surface, but store one-third of soil carbon. Peat soils are formed by the build-up of partially decomposed organic matter under waterlogged anoxic conditions. Most peat is found in cool climatic regions where unimpeded decomposition is slower, but deposits are also found under some tropical swamp forests. Here we present field measurements from one of the world's most extensive regions of swamp forest, the Cuvette Centrale depression in the central Congo Basin. We find extensive peat deposits beneath the swamp forest vegetation (peat defined as material with an organic matter content of at least 65 per cent to a depth of at least 0.3 metres). Radiocarbon dates indicate that peat began accumulating from about 10,600 years ago, coincident with the onset of more humid conditions in central Africa at the beginning of the Holocene. The peatlands occupy large interfluvial basins, and seem to be largely rain-fed and ombrotrophic-like (of low nutrient status) systems. Although the peat layer is relatively shallow (with a maximum depth of 5.9 metres and a median depth of 2.0 metres), by combining in situ and remotely sensed data, we estimate the area of peat to be approximately 145,500 square kilometres (95 per cent confidence interval of 131,900-156,400 square kilometres), making the Cuvette Centrale the most extensive peatland complex in the tropics. This area is more than five times the maximum possible area reported for the Congo Basin in a recent synthesis of pantropical peat extent. We estimate that the peatlands store approximately 30.6 petagrams (30.6 × 10 15  grams) of carbon belowground (95 per cent confidence interval of 6.3-46.8 petagrams of carbon)-a quantity that is similar to the above-ground carbon stocks of the tropical forests of the entire Congo Basin. Our result for the Cuvette Centrale increases the best estimate of global tropical peatland carbon stocks by 36 per cent, to 104.7 petagrams of carbon (minimum estimate of 69.6 petagrams of carbon; maximum estimate of 129.8 petagrams of carbon). This stored carbon is vulnerable to land-use change and any future reduction in precipitation.

High soil solution carbon and nitrogen concentrations in a drained Atlantic bog are reduced to natural levels by 10 years of rewetting

NASA Astrophysics Data System (ADS)

Frank, S.; Tiemeyer, B.; Gelbrecht, J.; Freibauer, A.

2014-04-01

Anthropogenic drainage of peatlands releases additional greenhouse gases to the atmosphere, and dissolved carbon (C) and nutrients to downstream ecosystems. Rewetting drained peatlands offers a possibility to reduce nitrogen (N) and C losses. In this study, we investigate the impact of drainage and rewetting on the cycling of dissolved C and N as well as on dissolved gases, over a period of 1 year and a period of 4 months. We chose four sites within one Atlantic bog complex: a near-natural site, two drained grasslands with different mean groundwater levels and a former peat cutting area rewetted 10 years ago. Our results clearly indicate that long-term drainage has increased the concentrations of dissolved organic carbon (DOC), ammonium, nitrate and dissolved organic nitrogen (DON) compared to the near-natural site. DON and ammonium contributed the most to the total dissolved nitrogen. Nitrate concentrations below the mean groundwater table were negligible. The concentrations of DOC and N species increased with drainage depth. In the deeply-drained grassland, with a mean annual water table of 45 cm below surface, DOC concentrations were twice as high as in the partially rewetted grassland with a mean annual water table of 28 cm below surface. The deeply drained grassland had some of the highest-ever observed DOC concentrations of 195.8 ± 77.3 mg L-1 with maximum values of >400 mg L-1. In general, dissolved organic matter (DOM) at the drained sites was enriched in aromatic moieties and showed a higher degradation status (lower DOC to DON ratio) compared to the near-natural site. At the drained sites, the C to N ratios of the uppermost peat layer were the same as of DOM in the peat profile. This suggests that the uppermost degraded peat layer is the main source of DOM. Nearly constant DOM quality through the profile furthermore indicated that DOM moving downwards through the drained sites remained largely biogeochemically unchanged. Unlike DOM concentration, DOM quality and dissolved N species distribution were similar in the two grasslands and thus unaffected by the drainage depth. Methane production during the winter months at the drained sites was limited to the subsoil, which was quasi-permanently water saturated. The recovery of the water table in the winter months led to the production of nitrous oxide around mean water table depth at the drained sites. The rewetted and the near-natural site had comparable DOM quantity and quality (DOC to DON ratio and aromaticity). 10 years after rewetting quasi-pristine biogeochemical conditions have been re-established under continuously water logged conditions in the former peat cut area. Only the elevated dissolved methane and ammonium concentrations reflected the former disturbance by drainage and peat extraction. Rewetting via polder technique seems to be an appropriate way to revitalize peatlands on longer timescales and to improve the water quality of downstream water bodies.

New Approach in Modelling Indonesian Peat Fire Emission

NASA Astrophysics Data System (ADS)

Putra, E. I.; Cochrane, M. A.; Saharjo, B.; Yokelson, R. J.; Stockwell, C.; Vetrita, Y.; Zhang, X.; Hagen, S. C.; Nurhayati, A. D.; Graham, L.

2017-12-01

Peat fires are a serious problem for Indonesia, producing devastating environmental effects and making the country the 3rd largest emitter of CO2. Extensive fires ravaged vast areas of peatlands in Sumatra, Kalimantan and Papua during the pronounced El-Nino of 2015, causing international concern when the resultant haze blanketed Indonesia and neighboring countries, severely impacting the health of millions of people. Our recent unprecedented in-situ studies of aerosol and gas emissions from 35 peat fires of varying depths near Palangka Raya, Central Kalimantan have documented the range and variability of emissions from these major fires. We strongly suggest revisions to previously recommended IPPC's emission factors (EFs) from peat fires, notably: CO2 (-8%), CH4 (-55%), NH3 (-86%), and CO (+39%). Our findings clearly showed that Indonesian carbon equivalent measurements (100 years) might have been 19% less than what current IPCC emission factors indicate. The results also demonstrate the toxic air quality in the area with HCN, which is almost only emitted by biomass burning, accounting for 0.28% and the carcinogenic compound formaldehyde 0.04% of emissions. However, considerable variation in emissions may exist between peat fires of different Indonesian peat formations, illustrating the need for additional regional field emissions measurements for parameterizing peatland emissions models for all of Indonesia's major peatland areas. Through the continuous mutual research collaboration between the Indonesian and USA scientists, we will implement our standardized field-based analyses of fuels, hydrology, peat burning characteristics and fire emissions to characterize the three major Indonesian peatland formations across four study provinces (Central Kalimantan, Riau, Jambi and West Papua). We will provide spatial and temporal drivers of the modeled emissions and validate them at a national level using biomass burning emissions estimations derived from Visible/Infrared Imager and Radiometer Suite (VIIRS). Multiple LiDAR datasets (2014, 2011, 2007) for Kalimantan will be used to quantify model accuracy, and new work will be undertaken to quantify uncertainty in our most recent LiDAR-based digital terrain model (DTM), further improving assessments of modelling errors.

Early age compressive strength, porosity, and sorptivity of concrete using peat water to produce and cure concrete

NASA Astrophysics Data System (ADS)

Olivia, Monita; Ismeddiyanto, Wibisono, Gunawan; Sitompul, Iskandar R.

2017-09-01

Construction in peatland has faced scarce water sources for mixing and curing concrete. It is known that peat water has high organic content and low pH that can be harmful to concrete in the environment. In some remote areas in Riau Province, contractors used peat water directly without sufficient treatments to comply with SKSNI requirements of concrete mixing water. This paper presents a study of compressive strength, porosity and sorptivity of Ordinary Portland Cement (OPC) and blended OPC-Palm Oil Fuel Ash (OPC-POFA) concrete. The specimens were mixed using natural water and peat water, then some of them were cured in fresh water and peat water. Six mixtures were investigated using a variation of cement, mixing water and curing water. Tap water is used as control mixing and curing water for all specimens. The compressive strength, porosity and sorptivity were calculated at seven and 28 days. Results indicate that the use of peat water will cause low compressive strength, high porosity and sorptivity for both OPC and OPC-POFA concrete. Using peat water and curing the specimens in tap water could improve the early strength, porosity and sorptivity of OPC concrete; however, it has an adverse effect on OPC-POFA specimens. The properties of early age concrete of both types (OPC and OPC-POFA) using peat water were as good as those with tap water. Therefore, it is suggested that peat water should be considered as mixing and curing water for concrete where tap water resources are scarce. Investigation of its long-term properties, as well as extending the observed age of concrete is recommended before any use of peat water.

Development and carbon sequestration of tropical peat domes in south-east Asia: links to post-glacial sea-level changes and Holocene climate variability

NASA Astrophysics Data System (ADS)

Dommain, René; Couwenberg, John; Joosten, Hans

2011-04-01

Tropical peatlands of SE-Asia represent a significant terrestrial carbon reservoir of an estimated 65 Gt C. In this paper we present a comprehensive data synthesis of radiocarbon dated peat profiles and 31 basal dates of ombrogenous peat domes from the lowlands of Peninsular Malaysia, Sumatra and Borneo and integrate our peatland data with records of past sea-level and climate change in the region. Based on their developmental features three peat dome regions were distinguished: inland Central Kalimantan (Borneo), Kutai basin (Borneo) and coastal areas across the entire region. With the onset of the Holocene the first peat domes developed in Central Kalimantan as a response to rapid post-glacial sea-level rise over the Sunda Shelf and intensification of the Asian monsoon. Peat accumulation rates in Central Kalimantan strongly declined after 8500 cal BP in close relation to the lowering rate of the sea-level rise and possibly influenced by the regional impact of the 8.2 ka event. Peat growth in Central Kalimantan apparently ceased during the Late Holocene in association with amplified El Niño activity as exemplified by several truncated peat profiles. Peat domes from the Kutai basin are all younger than ˜8300 cal BP. Peat formation and rates of peat accumulation were driven by accretion rates of the Mahakam River and seemingly independent of climate. Most coastal peat domes, the largest expanse of SE-Asian peatlands, initiated between 7000 and 4000 cal BP as a consequence of a Holocene maximum in regional rainfall and the stabilisation and subsequent regression of the sea-level. These boundary conditions induced the highest rates of peat accumulation of coastal peat domes. The Late Holocene sea-level regression led to extensive new land availability that allowed for continued coastal peat dome formation until the present. The time weighted mean Holocene peat accumulation rate is 0.54 mm yr -1 for Central Kalimantan, 1.89 mm yr -1 for Kutai and 1.77 mm yr -1 for coastal domes of Sumatra and Borneo. The mean Holocene carbon sequestration rates amount to 31.3 g C m -2 yr -1 for Central Kalimantan and 77.0 g C m -2 yr -1 for coastal sites, which makes coastal peat domes of south-east Asia the spatially most efficient terrestrial ecosystem in terms of long term carbon sequestration.

Twelve weeks supplementation with an extended-release caffeine and ATP-enhancing supplement may improve body composition without affecting hematology in resistance-trained men.

PubMed

Joy, Jordan M; Vogel, Roxanne M; Moon, Jordan R; Falcone, Paul H; Mosman, Matt M; Kim, Michael P

2016-01-01

Increased ATP levels may enhance training-induced muscle accretion and fat loss, and caffeine is a known ergogenic aid. A novel supplement containing ancient peat and apple extracts has reported enhanced mitochondrial ATP production and it has been coupled with an extended-release caffeine. Therefore, the purpose of this investigation was to determine the effects of this supplement on body composition when used in conjunction with 12 weeks of resistance training. Twenty-one resistance-trained subjects (27.2 ± 5.6y; 173.5 ± 5.7 cm; 82.8 ± 12.0 kg) completed this study. Subjects supplemented daily with either 1 serving of the supplement (TRT), which consisted of 150 mg ancient peat and apple extracts, 180 mg blend of caffeine anhydrous and pterostilbene-bound caffeine, and 38 mg B vitamins, or an equal-volume, visually-identical placebo (PLA) 45 min prior to training or at the same time of day on rest days. Supervised resistance training consisted of 8 weeks of daily undulating periodized training followed by a 2-week overreach and a 2-week taper phase. Body composition was assessed using DEXA and ultrasound at weeks 0, 4, 8, 10, and 12. Vital signs and blood markers were assessed at weeks 0, 8, and 12. Significant group x time (p < 0.05) interactions were present for cross-sectional area of the rectus femoris, which increased in TRT (+1.07 cm(2)) versus PLA (-0.08 cm(2)), as well as muscle thickness (TRT: +0.49 cm; PLA: +0.04 cm). A significant group x time (p < 0.05) interaction existed for creatinine (TRT: +0.00 mg/dL; PLA: +0.15 mg/dL) and estimated glomerular filtration rate (TRT: -0.70 mL/min/1.73; PLA: -14.6 mL/min/1.73), which remained within clinical ranges, but no other significant observations were observed. Supplementation with a combination of extended-release caffeine and ancient peat and apple extracts may enhance resistance training-induced skeletal muscle hypertrophy without adversely affecting blood chemistry.

Geohydrology of the glacial-outwash aquifer in the Baldwinsville area, Seneca River, Onondaga County, New York

USGS Publications Warehouse

Pagano, Timothy S.; Terry, David B.; Ingram, Arlynn W.

1986-01-01

Seven sheets of map data comprise this geohydrologic report. Sheet 1, surficial geology, illustrates the distribution of: open water areas; artificial fill; made land; urban land; alluvial silt and sand; alluvial sand and gravel; peat, marl, muck and clay; lake silt and/or clay; delta sand and gravel; beach sand and gravel; outwash sand and gravel; ice contact sand and ground; thick till cover bedrock; and thin till over bedrock over the Baldwinsville Area. Sheet 2, geologic sections, shows the layering of the aforementioned components below the surface layer. Sheet 3 illustrates the water infiltration of soil zone. Sheet 4 depicts the aquifer thickness. Sheet 5 illustrates the potentiometric surface, and Sheet 6 the well yield. Finally, Sheet 7 shows the land use in the region, specifically: industrial and extractive; commercial and services; transportation; farmland; forestland; residential; open public land; and water and wetlands. (Lantz-PTT)

Past Peatland Distribution as an Indicator of Hydroclimate and Temperature

NASA Astrophysics Data System (ADS)

Treat, C. C.; Jones, M.; Lacourse, T.; Payne, R.; Peteet, D. M.; Sannel, B.; Stelling, J.; Talbot, J.; Williams, C. J.; Kleinen, T.; Grosse, G.; Yu, Z.; Finkelstein, S. A.; Broothaerts, N.; Dommain, R.; Kuhry, P.; Lähteenoja, O.; Dalton, A.; Notebaert, B.; Swindles, G. T.; Tarnocai, C.; Verstraeten, G.; Xia, Z.; Brovkin, V.

2016-12-01

Peatlands, wetlands with > 30 cm of organic sediment, cover more than 3 x 106 km2 of the earth surface and have been accumulating carbon and sediments throughout the Holocene. The location of peatland formation and accumulation has been dynamic over time, as peat formation in areas like Alaska and the West Siberian Lowlands preceded peat formation in Fennoscandia and Eastern North America due to more favorable climate for peat formation. Using the geographic distribution of peatlands in the past can indicate general climatic conditions, including hydroclimate, given that the underlying geology is well understood. Peatlands form under a variety of climatic conditions and landscape positions but do not persist under arid conditions, instead requiring either humid conditions or cold temperatures. However, peatlands may have existed in the past in areas not currently suitable for peatland formation and persistence, but where peats can be found at depth within the sediment column. Here we map the locations of histic paleosols, relict peat, and buried peats since the Last Glacial Maximum using a compilation of sites from previous studies. We compare these records of past peatland distribution to present-day peatland distribution. We evaluate regional differences in timing of peatland development in these buried peatlands to the development of extant peatlands. Finally, we compare the timing of past peatland extent to the to modeled paleoclimate during the Quaternary. In addition to implications for paleoclimate, these past peatlands are not well accounted for in present-day soil carbon stocks but could be an important component of deep soil carbon pools.

Peat Biomass Smoke Particle Exposure in Rats Decreases ...

EPA Pesticide Factsheets

Wildland fires, favored by prolonged drought and rising temperatures, generate significant amounts of ambient particulate matter (PM), which has been linked to adverse health outcomes. The eastern North Carolina peat fires of Pocosin Lake in 2008 and Pains Bay in 2011 were some of the more prominent recent wildland fires and were associated with increased cardiovascular hospitalizations. The biological impacts of peat biomass emissions and the specific mechanisms driving these responses are unclear. The purpose of this study was to investigate the cardiopulmonary responses of peat biomass smoke exposure in rats. We hypothesized that PM exposure would dose-dependently alter cardiopulmonary function. Male Sprague-Dawley rats were exposed to 30 µg (Lo PM) or 300 µg (Hi PM) of peat biomass smoke PM extracts suspended in 200 µL of saline, or saline vehicle alone by oropharyngeal aspiration (OA). Immediately following OA rats were placed in a whole-body plethysmograph and ventilatory data were recorded for 12 minutes. One day following OA, rats were anesthetized with isoflurane for ultrasound assessment of cardiovascular function. Hi PM caused decreases in expiratory timing as early as 4-6 minutes after exposure relative to Lo PM (p = 0.02) and Vehicle (p= 0.06), which resolved shortly thereafter. One day after OA, ultrasounds revealed that Hi PM exposure increased end diastolic volume (EDV) by 16% (p = 0.03) over Vehicle and 13% (p = 0.06) over Lo PM. In addition,

Uranium delivery and uptake in a montane wetland, north-central Colorado, USA

USGS Publications Warehouse

Schumann, R. Randall; Zielinski, Robert A.; Otton, James K.; Pantea, Michael P.; Orem, William H.

2017-01-01

Comprehensive sampling of peat, underlying lakebed sediments, and coexisting waters of a naturally uraniferous montane wetland are combined with hydrologic measurements to define the important controls on uranium (U) supply and uptake. The major source of U to the wetland is groundwater flowing through locally fractured and faulted granite gneiss of Proterozoic age. Dissolved U concentrations in four springs and one seep ranged from 20 to 83 ppb (μg/l). Maximum U concentrations are ∼300 ppm (mg/kg) in lakebed sediments and >3000 ppm in peat. Uranium in lakebed sediments is primarily stratabound in the more organic-rich layers, but samples of similar organic content display variable U concentrations. Post-depositional modifications include variable additions of U delivered by groundwater. Uranium distribution in peat is heterogeneous and primarily controlled by proximity to groundwater-fed springs and seeps that act as local point sources of U, and by proximity to groundwater directed along the peat/lakebeds contact. Uranium is initially sorbed on various organic components of peat as oxidized U(VI) present in groundwater. Selective extractions indicate that the majority of sorbed U remains as the oxidized species despite reducing conditions that should favor formation of U(IV). Possible explanations are kinetic hindrances related to strong complex formation between uranyl and humic substances, inhibition of anaerobic bacterial activity by low supply of dissolved iron and sulfate, and by cold temperatures.

Can carbon offsetting pay for upland ecological restoration?

NASA Astrophysics Data System (ADS)

Worrall, F.

2012-04-01

Upland peat soils represent a large terrestrial carbon store and as such have the potential to be either an ongoing net sink of carbon or a significant net source of carbon. In the UK many upland peats are managed for a range of purposes but these purposes have rarely included carbon stewardship. However, there is now an opportunity to consider whether management practices could be altered to enhance storage of carbon in upland peats. Further, there are now voluntary and regulated carbon trading schemes operational throughout Europe that mean stored carbon, if verified, could have an economic and tradeable value. This means that new income streams could become available for upland management. The 'Sustainable Uplands' RELU project has developed a model for calculating carbon fluxes from peat soils that covers all carbon uptake and release pathways (e.g. fluvial and gaseous pathways). The model has been developed so that the impact of common management options within UK upland peats can be considered. The model was run for a decade from 1997-2006 and applied to an area of 550 km2 of upland peat soils in the Peak District. The study estimates that the region is presently a net sink of -62 Ktonnes CO2 equivalent at an average export of -136 tonnes CO2 equivalent/km2/yr.. If management interventions were targeted across the area the total sink could increase to -160 Ktonnes CO2/yr at an average export of -219 tonnes CO2 equivalent/km2/yr. However, not all interventions resulted in a benefit; some resulted in increased losses of CO2 equivalents. Given present costs of peatland restoration and value of carbon offsets, the study suggests that 51% of those areas, where a carbon benefit was estimated by modelling for targeted action of management interventions, would show a profit from carbon offsetting within 30 years. However, this percentage is very dependent upon the price of carbon used.

Artificial soils from alluvial tin mining wastes in Malaysia--a study of soil chemistry following experimental treatments and the impact of mycorrhizal treatment on growth and foliar chemistry.

PubMed

Tompkins, David S; Bakar, Baki B; Hill, Steve J

2012-01-01

For decades Malaysia was the world's largest producer of Sn, but now the vast open cast mining operations have left a legacy of some 100,000 ha of what is effectively wasteland, covered with a mosaic of tailings and lagoons. Few plants naturally recolonise these areas. The demand for such land for both urban expansion and agricultural use has presented an urgent need for better characterisation. This study reports on the formation of artificial soils from alluvial Sn mining waste with a focus on the effects of experimental treatments on soil chemistry. Soil organic matter, clay, and pH were manipulated in a controlled environment. Adding both clay tailings and peat enhanced the cation exchange capacity of sand tailings but also reduced the pH. The addition of peat reduced the extractable levels of some elements but increased the availability of Ca and Mg, thus proving beneficial. The use of clay tailings increased the levels of macro and micronutrients but also released Al, As, La, Pb and U. Additionally, the effects of soil mix and mycorrhizal treatments on growth and foliar chemistry were studied. Two plant species were selected: Panicum milicaeum and Pueraria phaseoloides. Different growth patterns were observed with respect to the additions of peat and clay. The results for mycorrhizal treatment (live inoculum or sterile carrier medium) are more complex, but both resulted in improved growth. The use of mycorrhizal fungi could greatly enhance rehabilitation efforts on sand tailings.

Illuminating Geochemical Controls of Methane Oxidation Along a Gradient of Permafrost Thaw

NASA Astrophysics Data System (ADS)

Perryman, C. R.; Kashi, N.; McCalley, C. K.; Malhotra, A.; Giesler, R.; Varner, R.

2017-12-01

Increases in annual mean temperature in the subarctic have accelerated the thaw of organic-rich permafrost peatlands, exacerbating methane (CH4) production from microbial decomposition of peat deposits and subsequent CH4 emissions. Methanotrophic bacteria may oxidize/consume upwards of 90% of produced CH4 in some settings, pending substrate availability and environmental conditions. Redox chemistry may also control the rate of CH4 oxidation in thawing permafrost areas, particularly redox potential (Eh) and the availability of oxygen (O2) and other terminal electron receptors. We investigated potential CH4 oxidation rates across a permafrost thaw gradient in Stordalen Mire (68°21'N,18°49'E) near Abisko, Sweden. Methane oxidation rates for sites from thawing and collapsed palsa, semi-wet Sphagnum, and open-water sedge sites were determined through laboratory incubations. Peat cores were extracted from two depths at each site and incubated at in situ temperatures and CH4 concentrations. Headspace samples were collected over a 48-hour period and analyzed for CH4 concentration using flame ionization detection gas chromatography (GC-FID). Dissolved O2, Eh, and dissolved CH4 were measured in sites with porewater. Oxidation rates ranged from <0.1 to 19 μg of CH4 per gram of dry biomass per day. Eh remained positive (41.6 to 316.8 mV) with available dissolved O2 (0.3 - 5.2 mg/L) in all measurement locations down to 20cm, indicating in situ aerobic CH4 oxidation is viable across these environments. Potential CH4 oxidation rates increased with increasing dissolved CH4 concentration. Highest potential CH4 oxidation rates were found in open-water sedge sites. Eh and dissolved O2 were lowest at these sites, suggesting that methanotrophs with low-O2 demand may populate sedge areas. Furthermore, potential CH4 oxidation rates were higher at depth than at the surface in thawing palsa, suggesting CH4 oxidation may mitigate CH4 production triggered by warming in these actively thawing environments. Forthcoming elemental analyses of peat and pore water will further elucidate trends and geochemical controls of CH4 oxidation rates in thawing permafrost areas.

Biogeochemistry of carbon and related major and trace elements in peat bog soils of the middle taiga of Western Siberia (Russia).

NASA Astrophysics Data System (ADS)

Stepanova, V. A.; Mironycheva-Tokareva, N. P.; Pokrovsky, O. S.

2012-04-01

Global climate changes impact the status of wetland ecosystems shifting the balances of the carbon, macro-, and microelements cycles. This study aims to establish the features of accumulation and distribution of major- and trace elements in the organic layer of peat bog soils, belonging to different ecosystems of the oligotrophic bog complex located in the middle taiga of Western Siberia (Khanty-Mansiysk region, Russia). Key areas which are selected for this study include the following bog conjugate elementary ecosystems: higher ryam, lower ryam, ridge-hollow complex, and oligotrophic poor fen as characterized previously [1]. We have sampled various peat types along the entire length of the soil column (every 10 cm down to 3 m). Peat samples were analyzed for a wide range of macro- and microelements using an ICP-MS technique following full acid digestion in a microwave oven. These measurements allowed quantitative estimates of major- and trace elements in the peat deposits within the whole bog complex and individual elementary landscapes. Based on the data obtained, the lateral and radial geochemical structures of the bog landscapes were determined and clarified for the first time for middle taiga of the West Siberian plain. The similar regime of mineral nutrition during the complete bog landscape formation was detected for the peat deposits based on the measurements of some major- and trace elements (Ca, Fe, Mg, etc.). The vertical distribution of some major and some trace elements along the profile of peat column is rather uniform with relatively strong increase in the bottom organic layers. This strongly suggests the similarity of the processes of element accumulation in the peat and relatively weak post depositional redistribution of elements within the peat soil profile. Overall, obtained corroborate the existing view on chemical composition of peats being determined by botanical peat's components (which forms this peat deposit), atmospheric precipitation, position of ecosystems in the landscape (lateral migration) and types of bedrocks [2]. The results allow better understanding of the coupling between biogeochemical cycles of carbon and major and trace elements in peat soils in order to predict the future changes in both concentrations and stocks of chemical elements in the Western Siberia peat bog systems under climate warming.

Plant extracts in the control of Phytophthora cryptogea.

PubMed

Orlikowski, L B

2001-01-01

Grapefruit extract at dose 40 micrograms/cm3 inhibited Phytophtora cryptogea linear growth about 50% and almost completely suppressed zoosporangia formation. Drenching of gerbera plants with the extract at dose 165 micrograms/cm3 reduced population density of the pathogen about 70% and this high efficacy was noted at least one month after application. Treatment of gerberas with grapefruit extract resulted in protection of about 50% of plants against the pathogen. Biological activity of purple coneflower extract was lower than extract from grapefruit. Significant decrease of population density of the pathogen during the first 5 days and increase of gerbera healthy stand was observed, however, in peat treated with that extract.

In situ sulphate stimulation of mercury methylation in a boreal peatland: Toward a link between acid rain and methylmercury contamination in remote environments

NASA Astrophysics Data System (ADS)

Branfireun, Brian A.; Roulet, Nigel T.; Kelly, Carol. A.; Rudd, John W. M.

1999-09-01

Recent studies have found that "pristine" peatlands have high peat and pore water methylmercury (MeHg) concentrations and that peatlands may act as large sources of MeHg to the downstream aquatic system, depending upon the degree of hydrologie connectivity and catchment physiography. Sulphate-reducing bacteria have been implicated as principal methylators of inorganic mercury in many environments with previous research focused primarily on mercury methylation in aquatic sediments. Experiments in a poor fen in the Experimental Lakes Area, northwestern Ontario, Canada, demonstrated that the in situ addition of sulphate to peat and peat pore water resulted in a significant increase in pore water MeHg concentrations. As peatlands cover a large area of the Northern Hemisphere, this finding has potentially far ranging implications for the global mercury cycle, particularly in areas impacted by anthropogenically derived sulphate where the methylmercury fraction of total mercury species may be much larger than in nonimpacted environments.

Biogenic Gas Dynamics in Peat Soil Blocks using Ground Penetrating Radar: a Comparative Study in the Laboratory between Peat Soils from the Everglades and from two Northern Peatlands in Minnesota and Maine

NASA Astrophysics Data System (ADS)

Cabolova, Anastasija

Peatlands cover a total area of approximately 3 million square kilometers and are one of the largest natural sources of atmospheric methane ( CH4) and carbon dioxide (CO 2). Most traditional methods used to estimate biogenic gas dynamics are invasive and provide little or no information about lateral distribution of gas. In contrast, Ground Penetrating Radar (GPR) is an emerging technique for non-invasive investigation of gas dynamics in peat soils. This thesis establishes a direct comparison between gas dynamics (i.e. build-up and release) of four different types of peat soil using GPR. Peat soil blocks were collected at peatlands with contrasting latitudes, including the Everglades, Maine and Minnesota. A unique two-antenna GPR setup was used to monitor biogenic gas buildup and ebullition events over a period of 4.5 months, constraining GPR data with surface deformation measurements and direct CH 4 and CO2 concentration measurements. The effect of atmospheric pressure was also investigated. This study has implications for better understanding global gas dynamics and carbon cycling in peat soils and its role in climate change.

Northern Peatland Shifts Under Changing Climate and Their Impact on Permafrost

NASA Astrophysics Data System (ADS)

Shur, Y.; Jorgenson, T.; Kanevskiy, M. Z.

2014-12-01

Formation of peatlands depends primarily on climate and its interactions with hydrology, soil thermal regimes, plant composition, and nutrients. A water balance with precipitation exceeding evaporation is necessary for their formation. The rate of peat accumulation also greatly depends on thermal resources. The prominent impact of the water balance and temperature on peatland formation is evident in the West Siberia Lowland. The rate of peat accumulation steadily increases from arctic tundra to moss tundra, to forest tundra, to northern taiga, and to southern taiga. This increase is a result in increase in air temperature and length of the growing season because all of these zones have water balance favorable for peat formation. Further to south, evaporation prevails over precipitation and peat formation occurs only in isolated areas. Climate change will redefine geographical distribution of climatic and vegetation zones. It is predicted that in arctic and subarctic regions the difference between precipitation and evaporation will increase and as a result these regions will remain favorable to peat accumulation. With increase of thermal resources, the rate of peat accumulation will also increase. The Alaska Arctic Coastal Plain is of a special interest because it has thousands of shallow lakes, which due to warming climate would shift from open waterbodies to peatlands through shoreline paludification and infilling. The accumulation of organic matter will likely turn open water into shore fens and bogs, and eventually to peat plateaus, as is occurring in many boreal landscapes. Expected impact on permafrost in arctic and subarctic regions will include rise of the permafrost table, thickening of the ice-rich intermediate layer with ataxitic (suspended) cryostructure, and replacement of frost boils with earth hummocks. In the contemporary continuous permafrost zone, permafrost formed as climate-driven will be transformed into climate-driven ecosystem protected. Sphagnum mosses, which grow better under warm climates, is a dominant factor in this transformation. Terrestrialization of numerous shallow lakes on the Arctic Coastal Plain of Alaska will lower permafrost temperatures beneath them and in surrounding areas.

Potential compensation of hydrological extremes in headwaters: case study of upper Vltava River basin, Šumava Mts., Czechia

NASA Astrophysics Data System (ADS)

Kocum, Jan; Janský, Bohumír.; Česák, Julius

2010-05-01

Increasing frequency of catastrophic flash floods and extreme droughts in recent years results in an urgent need of solving of flood protection questions and measures leading to discharge increase in dry periods. Flattening of discharge call for the use of untraditional practices as a suitable complement to classical engineering methods. These measures could be represented by gradual increase of river catchment retention capacity in headstream areas. Very favorable conditions for this research solution are concentrated to the upper part of Otava River basin (Vltava River left tributary, Šumava Mts., southwestern Czechia) representing the core zone of a number of extreme floods in Central Europe and the area with high peat land proportion. A number of automatic ultrasound and hydrostatic pressure water level gauges, climatic stations and precipitation gauges and utilization of modern equipment and methods were used in chosen experimental catchments to assess the landscape retention potential and to find out rainfall-runoff relations in this area. Successively, the detailed analysis of peat land hydrological function was carried out. The peat bogs influence on runoff conditions were assessed by thorough comparison of runoff regimes in subcatchments with different peat land proportion. The peat bog influence on hydrological process can be considered also with respect to its affecting of water quality. Therefore, hydrological monitoring was completed by ion, carbon (TOC) and oxygen isotopes balance observing within periods of high or low discharges in order to precise runoff phases separation by means of anion deficiency. Pedological survey of different soil types and textures was carried out to precise the estimation of its water capacity. Detailed analyses of extreme runoff ascending and descending phases and minimum discharges in profiles closing several subcatchments with different physical-geographic conditions show higher peak flow frequency and their shorter reaction to causal amount of precipitation in the case of highly peaty areas, therefore more distinct runoff variability of streams draining peat land localities. These findings were affirmed by geochemical approach laboratory outcomes within the meaning of significant contribution of runoff from peat lands to the total runoff during extreme flood situations. An important component of rainfall-runoff process in source areas of czech rivers represented by snow conditions was analyses very in detail by means of monitoring of snow cover height and its water equivalent in chosen experimental catchments. Outcomes of this study should markedly help with significant precising of estimation of water storage retained in a snow cover. Consecutive runoff simulations using mathematical techniques would then improve a hydrological forecast. In terms of present dyking of former channels draining peat land represented by so called peat bog revitalization partial findings refer to positive effect during mean runoff situations but their considerably negative influence on runoff process in cases of extremely high discharges. In order to achieve retention potential enhancement in source areas of czech rivers an evaluation of possible former accumulative reservoirs (used for wood floating in former times) restoration which could function for example as dry (green) polders should be considered. The system of such small storage bins could function as an alternative and supplement to greater dam reservoirs. Possible spaces for water retention are measured by geodetic total station and modelled by suitable methods in GIS software. Existing outcomes advert to the fact that the effectiveness of such reservoir system would not have to be neglecting. By implementation of these unforceable measures realized in river headstream areas it could be contributed to reduction of peak flows and to increase of water resources during extreme droughts in future.

Maceral distributions in Illinois coals and their paleoenvironmental implications

USGS Publications Warehouse

Harvey, R.D.; Dillon, J.W.

1985-01-01

For purposes of assessing the maceral distribution of Illinois (U.S.A.) coals analyses were assembled for 326 face channel and drill core samples from 24 coal members of the Pennsylvanian System. The inertinite content of coals from the Missourian and Virgilian Series averages 16.1% (mineral free), compared to 9.4% for older coals from the Desmoinesian and older Series. This indicates there was generally a higher state of oxidation in the peat that formed the younger coals. This state probably resulted from greater exposure of these peats to weathering as the climate became drier and the water table lower than was the case for the older coals, although oxidation during allochthonous deposition of inertinite components is a genetic factor that needs further study to confirm the importance of the climate. Regional variation of the vitrinite-inertinite ratio (V-I), on a mineral- and micrinite-free basis, was observed in the Springfield (No. 5) and Herrin (No. 6) Coal Members to be related to the geographical position of paleochannel (river) deposits known to have been contemporaneous with the peats that formed these two coal strata. The V-I ratio is highest (generally 12-27) in samples from areas adjacent to the channels, and lower (5-11) some 10-20 km away. We interpret the V-I ratio to be an inverse index of the degree of oxidation to which the original peat was exposed. High V-I ratio coal located near the channels probably formed under more anoxic conditions than did the lower V-I ratio coal some distance away from the channels. The low V-I ratio coal probably formed in areas of the peat swamp where the watertable was generally lower than the channel areas. ?? 1986.

Bearing capacity of helical pile foundation in peat soil from different, diameter and spacing of helical plates

NASA Astrophysics Data System (ADS)

Fatnanta, F.; Satibi, S.; Muhardi

2018-03-01

In an area dominated by thick peat soil layers, driven piles foundation is often used. These piles are generally skin friction piles where the pile tips do not reach hard stratum. Since the bearing capacity of the piles rely on the resistance of their smooth skin, the bearing capacity of the piles are generally low. One way to increase the bearing capacity of the piles is by installing helical plates around the pile tips. Many research has been performed on helical pile foundation. However, literature on the use of helical pile foundation on peat soil is still hardly found. This research focus on the study of axial bearing capacity of helical pile foundation in peat soil, especially in Riau Province. These full-scale tests on helical pile foundation were performed in a rectangular box partially embedded into the ground. The box is filled with peat soil, which was taken from Rimbo Panjang area in the district of Kampar, Riau Province. Several helical piles with different number, diameter and spacing of the helical plates have been tested and analysed. The tests result show that helical pile with three helical plates of uniform diameter has better bearing capacity compared to other helical piles with varying diameter and different number of helical plates. The bearing capacity of helical pile foundation is affected by the spacing between helical plates. It is found that the effective helical plates spacing for helical pile foundation with diameter of 15cm to 35cm is between 20cm to 30cm. This behaviour may be considered to apply to other type of helical pile foundations in peat soil.

Characterization of the efficiency of sedimentation basins downstream of harvested peat bogs

NASA Astrophysics Data System (ADS)

Samson-Do, Myriam; St-Hilaire, André

2015-04-01

Peat harvesting is a very lucrative industry in the provinces of Quebec and New-Brunswick (Canada). Peat enters in many potting mix used for horticulture. However, harvesting this resource has some impacts on the environment. First, industries need to drain the peat bog to dry the superficial layer. Then, it is harvested with industrial vacuums and the underlying layer is allowed to dry. The drained water is laden with suspended sediments (mostly organic peat fibers) that may affect biota of the stream where it is discharged. To counter the problem, this water does not go directly on the stream but first flows through a sedimentation basin, built to reduce suspended sediment loads. This work focuses on characterizing and eventually modeling the efficiency of those sedimentation basins. Seven basins were studied in Rivière-du-Loup, St-Valère and Escoumins (Quebec, Canada). They each have a different ratio basin area/drained area (4.7 10-4 to 20.3 10-4). To continuously monitor the sediment loads (calculated from sediment concentrations and discharge) entering and leaving basins, a nephelometer and a level logger were installed in the water column upstream and downstream of sedimentation basins. Their trapping efficiency was measured during the ice-free period (May to October) and for each significant rain event, since it is known that the rain and subsequent runoff induce most of the peat transport in and out of the basin. Results show that the event efficiency decreases as the basin is filled up with trapped sediments. For one basin, the efficiency was 85August. Trapping efficiency can be used as a tool to estimate basin dimensions. This has been done for municipal sedimentation ponds that trap minerals and will be adapted to the current context, where the dominant sediment is organic.

The association of uranium with organic matter in Holocene peat: An experimental leaching study

USGS Publications Warehouse

Zielinski, R.A.; Meier, A.L.

1988-01-01

Uraniferous peat was sampled from surface layers of a Holocene U deposit in northeastern Washington State. Dried, sized, and homogenized peat that contained 5980 ??307 ppm U was subjected to a variety of leaching conditions to determine the nature and strength of U-organic bonding in recently accumulated organic matter. The results complement previous experimental studies of U uptake on peat and suggest some natural or anthropogenic disturbances that are favorable for remobilizing U. The fraction of U leached in 24 h experiments at 25??C ranged from 0 to 95%. The most effective leach solutions contained anions capable of forming stable dissolved complexes with uranyl (UO2+2) cation. These included H2SO4 (pH = 1.5) and concentrated (>0.01 M) solutions of sodium bicarbonate-carbonate (pH = 7.0-10.0), or sodium pyrophosphate (pH = 10). Effective leaching by carbonate and pyrophosphate in the absence of added oxidant, and the insignificant effect of added oxidant (as pressurized O2) strongly suggest that U is initially fixed on organic matter as an oxidized U(VI) species. Uranium is more strongly bound than some other polyvalent cations, based on its resistance to exchange in the presence of large excesses of dissolved Ca2+ and Cu2+. Measurements of the rate of U leaching indicate faster rates in acid solution compared to carbonate solution, and are consisten with simultaneous attack of sites with different affinities for U. Sulfuric acid appears a good choice for commercial extraction of U from mined peat. In situ disturbances such as overliming of peat soils, addition of fertilizers containing pyrophosphate, or incursions of natural carbonate-rich waters could produce significant remobilization of U, and possibly compromise the quality of local domestic water supplies. ?? 1988.

Analysis and Characterization of Organic Carbon in Early Holocene Wetland Paleosols using Ramped Pyrolysis 14C and Biomarkers

NASA Astrophysics Data System (ADS)

Vetter, L.; Schreiner, K. M.; Fernandez, A.; Rosenheim, B. E.; Tornqvist, T. E.

2014-12-01

Radiocarbon analyses are a key tool for quantifying the dynamics of carbon cycling and storage in both modern soils and Quaternary paleosols. Frequently, bulk 14C dates of paleosol organic carbon provide ages older than the time of soil burial, and 14C dates of geochemical fractions such as alkali and acid extracts (operationally defined as humic acids) can provide anomalously old ages when compared to coeval plant macrofossil dates. Ramped pyrolysis radiocarbon analysis of sedimentary organic material has been employed as a tool for investigating 14C age spectra in sediments with multiple organic carbon sources. Here we combine ramped pyrolysis 14C analysis and biomarker analysis (lignin-phenols and other cupric oxide products) to provide information on the source and diagenetic state of the paleosol organic carbon. We apply these techniques to immature early Holocene brackish wetland entisols from three sediment cores in southeastern Louisiana, along with overlying basal peats. Surprisingly, we find narrow 14C age spectra across all thermal aliquots from both paleosols and peats. The weighted bulk 14C ages from paleosols and overlying peats are within analytical error, and are comparable to independently analyzed 14C AMS dates from charcoal fragments and other plant macrofossils from each peat bed. Our results suggest high turnover rates of carbon in soils relative to input of exogenous carbon sources. These data raise broader questions about processes within the active soil and during pedogenesis and burial of paleosols that can effectively homogenize radiocarbon content in soils across the thermochemical spectrum. The concurrence of paleosol and peat 14C ages also suggests that, in the absence of peats with identifiable plant macrofossils, ramped pyrolysis 14C analyses of paleosols may be used to provide ages for sea-level indicators.

Is it clean or contaminated soil? Using petrogenic versus biogenic GC-FID chromatogram patterns to mathematically resolve false petroleum hydrocarbon detections in clean organic soils: a crude oil-spiked peat microcosm experiment.

PubMed

Kelly-Hooper, Francine; Farwell, Andrea J; Pike, Glenna; Kennedy, Jocelyn; Wang, Zhendi; Grunsky, Eric C; Dixon, D George

2013-10-01

The Canadian Council of Ministers of the Environment (CCME) reference method for the Canada-wide standard (CWS) for petroleum hydrocarbon (PHC) in soil provides chemistry analysis standards and guidelines for the management of contaminated sites. However, these methods can coextract natural biogenic organic compounds (BOCs) from organic soils, causing false exceedences of toxicity guidelines. The present 300-d microcosm experiment used CWS PHC tier 1 soil extraction and gas chromatography-flame ionization detector (GC-FID) analysis to develop a new tier 2 mathematical approach to resolving this problem. Carbon fractions F2 (C10-C16), F3 (C16-C34), and F4 (>C34) as well as subfractions F3a (C16-C22) and F3b (C22-C34) were studied in peat and sand spiked once with Federated crude oil. These carbon ranges were also studied in 14 light to heavy crude oils. The F3 range in the clean peat was dominated by F3b, whereas the crude oils had approximately equal F3a and F3b distributions. The F2 was nondetectable in the clean peat but was a significant component in crude oil. The crude oil–spiked peat had elevated F2 and F3a distributions. The BOC-adjusted PHC F3 calculation estimated the true PHC concentrations in the spiked peat. The F2:F3b ratio of less than 0.10 indicated PHC absence in the clean peat, and the ratio of greater than or equal to 0.10 indicated PHC presence in the spiked peat and sand. Validation studies are required to confirm whether this new tier 2 approach is applicable to real-case scenarios. Potential adoption of this approach could minimize unnecessary ecological disruptions of thousands of peatlands throughout Canada while also saving millions of dollars in management costs. © 2013 SETAC.

Historical peat loss explains limited short-term response of drained blanket bogs to rewetting.

PubMed

Williamson, Jennifer; Rowe, Edwin; Reed, David; Ruffino, Lucia; Jones, Peter; Dolan, Rachel; Buckingham, Helen; Norris, David; Astbury, Shaun; Evans, Chris D

2017-03-01

This study assessed the short-term impacts of ditch blocking on water table depth and vegetation community structure in a historically drained blanket bog. A chronosequence approach was used to compare vegetation near ditches blocked 5 years, 4 years and 1 year prior to the study with vegetation near unblocked ditches. Plots adjacent to and 3 m away from 70 ditches within an area of blanket bog were assessed for floristic composition, aeration depth using steel bars, and topography using LiDAR data. No changes in aeration depth or vegetation parameters were detected as a function of ditch-blocking, time since blocking, or distance from the ditch, with the exception of non-Sphagnum bryophytes which had lower cover in quadrats adjacent to ditches that had been blocked for 5 years. Analysis of LiDAR data and the observed proximity of the water table to the peat surface led us to conclude that the subdued ecosystem responses to ditch-blocking were the result of historical peat subsidence within a 4-5 m zone either side of each ditch, which had effectively lowered the peat surface to the new, ditch-influenced water table. We estimate that this process led to the loss of around 500,000 m 3 peat within the 38 km 2 study area following drainage, due to a combination of oxidation and compaction. Assuming that 50% of the volume loss was due to oxidation, this amounts to a carbon loss of 11,000 Mg C over this area, i.e. 3 Mg C ha -1 . The apparent 'self-rewetting' of blanket bogs in the decades following drainage has implications for their restoration as it suggests that there may not be large quantities of dry peat left to rewet, and that there is a risk of inundation (potentially leading to high methane emissions) along subsided ditch lines. Many peatland processes are likely to be maintained in drained blanket bog, including support of typical peatland vegetation, but infilling of lost peat and recovery of original C stocks are likely to take longer than is generally anticipated. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Trajectories of water table recovery following the re-vegetation of bare peat

NASA Astrophysics Data System (ADS)

Shuttleworth, Emma; Evans, Martin; Allott, Tim; Maskill, Rachael; Pilkington, Michael; Walker, Jonathan

2016-04-01

The hydrological status of blanket peat influences a wide range of peatland functions, such as runoff generation, water quality, vegetation distribution, and rates of carbon sequestration. The UK supports 15% of the world's blanket peat cover, but much of this vital resource is significantly degraded, impacted by industrial pollution, overgrazing, wildfire, and climatic shifts. These pressures have produced a unique landscape characterised by severe gully erosion and extensive areas of bare peat. This in turn has led water tables to become substantially drawn down, impacting peatland function and limiting the resilience of these landscapes to future changes in climate. The restoration of eroding UK peatlands is a major conservation concern, and landscape-scale interventions through the re-vegetation of bare peat is becoming increasingly extensive in areas of upland Britain. Water table is the primary physical parameter considered in the monitoring of many peatland restoration projects, and there is a wealth of data on individual monitoring programmes which indicates that re-vegetation significantly raises water tables. This paper draws on data from multiple restoration projects carried out by the Moors for the Future Partnership in the Southern Pennines, UK, covering a range of stages in the erosion-restoration continuum, to assess the trajectories of water table recovery following re-vegetation. This will allow us to generate projections of future water table recovery, which will be of benefit to land managers and conservation organisations to inform future restoration initiatives.

Impact of drainage on wettability of fen peat-moorsh soils

NASA Astrophysics Data System (ADS)

Szajdak, L.; Szatyłowicz, J.; Brandyk, T.

2009-04-01

High water retention in peat is attributed to structural voids (macro-pores) due to the partial degradation of the structure of peat-forming plants, and molecular absorption sites (micro-pores) associated with the formation of humic substances. Water retention by the heterogeneously-structured system in peat organic matter depends on the chemical structure of solid surfaces. These naturally wet solids, if dried sufficiently, lose the ability to rewet quickly when immersed in water. The ability of peat surfaces to attract and hold water is attributed to hydrophilic functional groups which characterize the organic substances of peat. The investigations of chemical and physical properties were performed for three different peat-moorsh soils located in the Biebrza River Valley in Poland. All examined soils were used as meadow. Soil samples were taken from two depths: 5-10 cm (moorsh) and 50-80 cm (peat). Total organic carbon (TOC), dissolved organic carbon (DOC) and humic acids (HA) extracted from these samples were analysed. Also basic physical properties such as ash content and bulk density were measured. Wetting behavior of soils was quantified using water drop penetration time test (WDPT) and measured values of the soil-water contact angle using sessile drop method. The measurements were conducted on air-dry soil samples which volumetric moisture content was not exceeding 7%. The significant differences in the concentrations of TOC, DOC and properties of HA between two investigated depth of among peat and moorsh samples were observed. The measured concentrations of total organic carbon in the considered soils ranged from 37.2 to 45.6%. Generally, the decrease of total organic carbon concentration with depth of profiles was observed. The contents of dissolved organic carbon in the soils ranged from 5.3 to 19.4%. The quantities of dissolved organic carbon decreased simultaneously with E4/E6 values and with the depth of the soil profiles. For the investigated peat's, an increase of the depth is accompanied by the decrease in the degree of humification or an increase in chemical maturity of HA. The measured values of the contact angle for investigated soils were in the range from 81.4˚ to 114.3˚ what indicates their high water repellency. The WDPT was positively correlated with total organic carbon, organic matter and humic acids content while ash content, soil bulk density, pH and absorbance were correlated negatively. The highest value of correlation coefficient (statistically significant) was obtained for relation between WDPT and ash content. The soil water contact angle was less correlated with peat-moorsh soil properties in comparison with WDPT with one exception pH. The pH against the contact angle indicates tendency of increasing the contact angle with decreasing pH.

Long-Term Arctic Peatland Dynamics, Vegetation and Climate History of the Pur-Taz Region, Western Siberia

NASA Technical Reports Server (NTRS)

Peteet, Dorothy; Andreev, Andrei; Bardeen, William; Mistretta, Francesca

1998-01-01

Stratigraphic analyses of peat composition, LOI, pollen, spores, macrofossils, charcoal, and AMS ages are used to reconstruct the peatland, vegetation and climatic dynamics in the Pur-Taz region of western Siberia over 5000 years (9300 - 4500 BP). Section stratigraphy shows many changes from shallow lake sediment to different combinations of forested or open sedge, moss, and Equisetum fen and peatland environments. Macrofossil and pollen data indicate that Larix sibirica and Betula pubescens trees were first to arrive, followed by Picea obovata. The dominance of Picea macrofossils 6000-5000 BP in the Pur-Taz peatland along with regional Picea pollen maxima indicate warmer conditions and movement of the spruce treeline northward at this time. The decline of pollen and macrofossils from all of these tree species in uppermost peats suggests a change in the environment less favorable for their growth, perhaps cooler temperatures and/or less moisture. Of major significance is the evidence for old ages of the uppermost peats in this area of Siberia, suggesting a real lack of peat accumulation in recent millennia or recent oxidation of uppermost peat.

CO2 Efflux from Cleared Mangrove Peat

PubMed Central

Lovelock, Catherine E.; Ruess, Roger W.; Feller, Ilka C.

2011-01-01

Background CO2 emissions from cleared mangrove areas may be substantial, increasing the costs of continued losses of these ecosystems, particularly in mangroves that have highly organic soils. Methodology/Principal Findings We measured CO2 efflux from mangrove soils that had been cleared for up to 20 years on the islands of Twin Cays, Belize. We also disturbed these cleared peat soils to assess what disturbance of soils after clearing may have on CO2 efflux. CO2 efflux from soils declines from time of clearing from ∼10 600 tonnes km−2 year−1 in the first year to 3000 tonnes km2 year−1 after 20 years since clearing. Disturbing peat leads to short term increases in CO2 efflux (27 umol m−2 s−1), but this had returned to baseline levels within 2 days. Conclusions/Significance Deforesting mangroves that grow on peat soils results in CO2 emissions that are comparable to rates estimated for peat collapse in other tropical ecosystems. Preventing deforestation presents an opportunity for countries to benefit from carbon payments for preservation of threatened carbon stocks. PMID:21738628

CO2 efflux from cleared mangrove peat.

PubMed

Lovelock, Catherine E; Ruess, Roger W; Feller, Ilka C

2011-01-01

CO(2) emissions from cleared mangrove areas may be substantial, increasing the costs of continued losses of these ecosystems, particularly in mangroves that have highly organic soils. We measured CO(2) efflux from mangrove soils that had been cleared for up to 20 years on the islands of Twin Cays, Belize. We also disturbed these cleared peat soils to assess what disturbance of soils after clearing may have on CO(2) efflux. CO(2) efflux from soils declines from time of clearing from ∼10,600 tonnes km(-2) year(-1) in the first year to 3000 tonnes km(2) year(-1) after 20 years since clearing. Disturbing peat leads to short term increases in CO(2) efflux (27 umol m(-2) s(-1)), but this had returned to baseline levels within 2 days. Deforesting mangroves that grow on peat soils results in CO(2) emissions that are comparable to rates estimated for peat collapse in other tropical ecosystems. Preventing deforestation presents an opportunity for countries to benefit from carbon payments for preservation of threatened carbon stocks.

Effect of climate changes in the holocene on the distribution of humic substances in the profile of forest-tundra peat mounds

NASA Astrophysics Data System (ADS)

Vasilevich, R. S.; Beznosikov, V. A.

2017-11-01

The molecular composition of humic substances in permafrost peatlands of the forest-tundra zone in northeastern European Russia has been characterized for the first time on the basis of systematic studies. Changes in the molar x(H): x(C) ratio along the peat profiles have been revealed, which is due to the activation of cryogenic processes in the upper part of the seasonally thawing layer, the natural selection of condensed humic molecules, and the botanical composition and degree of degradation of peat, which reflect the climatic features of the area in the Holocene. Dry-peat soils of mounds are worse heated during the summer period because of the buffering effect of moss litter, which results in a lower degree of condensation of humic and fulvic acid molecules in the peat horizons down to the permafrost table. Transformation of quantitative and qualitative parameters of specific organic compounds occurs at the permafrost boundary of peatlands, which can serve as an indicator of recent climate changes in high latitudes.

Spatial Heterogeneity in the Properties of High-Moor Peat Soils under Local Pyrogenesis in Northeastern Sakhalin

NASA Astrophysics Data System (ADS)

Lipatov, D. N.; Shcheglov, A. I.; Manakhov, D. V.; Brekhov, P. T.

2016-02-01

The structure and properties of oligotrophic peat, oligotrophic peat gley, and pyrogenic oligotrophic peat soils identified on a plot 0.5 km2 in area in the northeast of Sakhalin Island have been studied. The vertical distributions of physicochemical, chemical, and ecotoxicological parameters in the profiles of some bog soil groups have been considered. An increase in ash content, a less acid reaction, and a deficit of available nitrogen and potassium have been revealed in the upper horizons of pyrogenic soils. No accumulation of mobile heavy metals is manifested in the pyrogenic horizons of peat soils. Statistical parameters of the spatial variation in pHKCl and total acidity, as well as the contents of ash, available phosphorus, exchangeable potassium, ammonium and nitrate nitrogen, mobile heavy metals (Cr, Ni, Cu, Zn, Cd, Pb), and benzo[ a]pyrene, have been calculated for the moss and sublitter horizons. The variation coefficients are 30-100% for most of the studied parameters and reach 100-200% for available phosphorus; ammonium nitrogen; and mobile Ni, Cu, Zn, and Cd. An increase in the content of benzo[ a]pyrene, although without MPC exceedance, is noted in the moss of pyrogenic soils and the peat horizons untouched by fires.

Physico-chemical and chemical properties of some coconut coir dusts for use as a peat substitute for containerised ornamental plants.

PubMed

Abad, Manuel; Noguera, Patricia; Puchades, Rosa; Maquieira, Angel; Noguera, Vicente

2002-05-01

Selected physico-chemical and chemical characteristics of 13 coconut coir dust (mesocarp pithy tissue plus short-length fibres) samples from Asia, America and Africa were evaluated as peat alternatives. All properties studied differed significantly between and within sources, and from the control Sphagnum peat. pH of coir dust was slightly acidic, whereas salinity varied dramatically between 39 and 597 mS m(-1) in the saturated media extract. The cation exchange capacity and carbon/nitrogen (C/N) ratio ranged from 31.7 to 95.4 cmol(c) kg(-1) and from 75 to 186, respectively. Most carbon was found as lignin and cellulose. The concentrations of available nitrogen, calcium, magnesium and micro-elements were low, while those of phosphorus and potassium were remarkably high (0.28-2.81 mol m(-3) and 2.97-52.66 mol m(-3) for P and K, respectively). Saline ion concentrations, especially chloride and sodium, were also high.

Spatial Analysis of Soil Subsidence in Peat Meadow Areas in Friesland in Relation to Land and Water Management, Climate Change, and Adaptation

NASA Astrophysics Data System (ADS)

Brouns, Karlijn; Eikelboom, Tessa; Jansen, Peter C.; Janssen, Ron; Kwakernaak, Cees; van den Akker, Jan J. H.; Verhoeven, Jos T. A.

2015-02-01

Dutch peatlands have been subsiding due to peat decomposition, shrinkage and compression, since their reclamation in the 11th century. Currently, subsidence amounts to 1-2 cm/year. Water management in these areas is complex and costly, greenhouse gases are being emitted, and surface water quality is relatively poor. Regional and local authorities and landowners responsible for peatland management have recognized these problems. In addition, the Netherlands Royal Meteorological Institute predicts higher temperatures and drier summers, which both are expected to enhance peat decomposition. Stakeholder workshops have been organized in three case study areas in the province of Friesland to exchange knowledge on subsidence and explore future subsidence rates and the effects of land use and management changes on subsidence rates. Subsidence rates were up to 3 cm/year in deeply drained parcels and increased when we included climate change in the modeling exercises. This means that the relatively thin peat layers in this province (ca 1 m) would shrink or even disappear by the end of the century when current practices continue. Adaptation measures were explored, such as extensive dairy farming and the production of new crops in wetter conditions, but little experience has been gained on best practices. The workshops have resulted in useful exchange of ideas on possible measures and their consequences for land use and water management in the three case study areas. The province and the regional water board will use the results to develop land use and water management policies for the next decades.

Seasonal variations in CO2 and CH4 fluxes of four different plant compositions of a Sphagnum-dominated Alpine peat bog

NASA Astrophysics Data System (ADS)

Drollinger, Simon; Maier, Andreas; Karer, Jasmin; Glatzel, Stephan

2017-04-01

Peatlands are the only type of ecosystems which have the ability to accumulate significant amounts of carbon (C) under undisturbed conditions. The amount of C sequestered in peatlands depends on the balance between gross primary production, ecosystem respiration and decomposition of plant material. Sphagnum-dominated bogs possess the greatest peat accumulation potential of all peatlands, thus in turn, feature highest C release potentials. Many studies report about the C balances of undisturbed northern peat bogs, however, little is known about the effects of peatland degradation on the C balance between different plant compositions within peat bog ecosystems. Particularly in the Alpine region, where temperature increase during the last century has been almost twice as high as the global mean. The investigated peat bog is located in the inner Alpine Enns valley in the Eastern Alps, Austria (N 47˚ 34.873' E 14˚ 20.810'). It is a pine peat bog covered by Sphagnum mosses and a present extent of about 62 ha. Due to increasing differences in surface height of the peatland compared to the surrounding areas and related lowered water retention capacity attributed to the subsidence of the adjacent intensively managed meadows on deeply drained peat soils, the function of the peatland as a carbon sink is strongly endangered. Hence, the current mean water table depth of the central peat bog area is about -12 cm. To reveal differences in peatland-atmosphere C exchanges within the peatland ecosystem, we investigated CO2 and CH4 fluxes of four different vegetation compositions (PM1-PM4) at the treeless central peat bog area. PM1 is dominated by the graminoids Rhynchospora alba and Eriophorum vaginatum. PM2 is inhabited by small individuals (< 35 cm) of the conifer Pinus mugo, whereas PM3 is dominated by the ericaceous plant Calluna vulgaris. PM4 again is populated by Pinus mugo, but higher growing (35 - 60 cm) and with corresponding higher amount of biomass. Fluxes were measured for at least 120 seconds with the closed dynamic chamber method using infrared gas analysers (UGGA, Los Gatos Research and LI-802, LI-COR Biosciences) at four study sites with three replicates each. Net ecosystem exchange was measured using transparent chambers, whereas soil respiration was revealed using opaque chambers. Measurements were conducted seasonally during the last two years with eight sampling periods. Here, we demonstrate the seasonal variations in CO2 and CH4 fluxes, evaluate the underlying factors being responsible for these variations, examine the differences in diurnal pattern during the seasons and compute the global warming potentials of the released greenhouse gases. Moreover, we estimate the annual C balance per site and revise the seasonal C fluxes by comparing the results with fluxes derived by eddy covariance method.

Permafrost peatland dynamics during the last millennia in NE European Russia and Finnish Lapland

NASA Astrophysics Data System (ADS)

Zhang, Hui; Väliranta, Minna; Piilo, Sanna; Amesbury, Matthew; Gallego-Sala, Angela; Charman, Dan

2016-04-01

Permafrost peatlands cover vast areas in circum-Arctic regions. Since the 1980s, annual temperatures in these areas have risen by ca. 2 °C and warming is projected to continue. Accordingly, the large carbon store in these peatlands may therefore be threatened. Alternatively, warming may increase productivity more than decomposition and peat accumulation rates may increase. To better understand how high latitude permafrost peatlands have responded to recent warming and what might be their future fate, we carried out detailed studies on two permafrost peatlands in NE Russia and two in Finnish Lapland. Our study methods included high resolution testate amoeba, plant macrofossil, C/N analyses, together with 210Pb and radiocarbon dating. We reconstructed changes in hydrological conditions, plant composition, and peat and carbon accumulation rates. Our preliminary results showed large variations in peat accumulation rates even within a very small area. Furthermore, testate amoeba and plant macrofossil data suggest variations in hydrological conditions during the last millennia. In the future, we will compare our regional data derived from different peatlands to each other, to climate reconstructions and to measured meteorological data.

UAV based 3D digital surface model to estimate paleolandscape in high mountainous environment

NASA Astrophysics Data System (ADS)

Mészáros, János; Árvai, Mátyás; Kohán, Balázs; Deák, Márton; Nagy, Balázs

2016-04-01

Our method to present current state of a peat bog was focused on the possible use of a UAV-system and later Structure-from-motion algorithms as processing technique. The peat bog site is located on the Vinderel Plateau, Farcǎu Massif, Maramures Mountains (Romania). The peat bog (1530 m a.s.l., N47°54'11", E24°26'37") lies below Rugasu ridge (c. 1820 m a.s.l.) and the locality serves as a conservation area for fallen down coniferous trees. Peat deposits were formed in a landslide concavity on the western slope of Farcǎu Massif. Nowadays the site is surrounded by a completely deforested landscape, and Farcǎu Massif lies above the depressed treeline. The peat bog has an extraordinary geomorphological situation, because a gully reached the bog and drained the water. In the recent past sedimentological and dendrochronological researches have been initiated. However, an accurate 3D digital surface model also needed for a complex paleoenvironmental research. Last autumn the bog and its surroundings were finally surveyed by a multirotor UAV developed in-house based on an open-source flight management unit and its firmware. During this survey a lightweight action camera (mainly to decrease payload weight) was used to take aerial photographs. While our quadcopter is capable to fly automatically on a predefined flight route, several over- and sidelapping flight lines were generated prior to the actual survey on the ground using a control software running on a notebook. Despite those precautions, limited number of batteries and severe weather affected our final flights, resulting a reduced surveyed area around peat bog. Later, during the processing we looked for a reliable tool which powerful enough to process more than 500 photos taken during flights. After testing several software Agisoft PhotoScan was used to create 3D point cloud and mesh about bog and its environment. Due to large number of photographs PhotoScan had to be configured for network processing to get reliable results and resolution. Based on the sediment layers of the peat bog together with the generated 3D surface model the paleoenvironment, the largest paleowater level can be reconstructed and we can estimate the dimension of the landslide which created the basin of the peat bog.

Polyphenols as enzyme inhibitors in different degraded peat soils: Implication for microbial metabolism in rewetted peatlands

NASA Astrophysics Data System (ADS)

Zak, Dominik; Roth, Cyril; Gelbrecht, Jörg; Fenner, Nathalie; Reuter, Hendrik

2015-04-01

Recently, more than 30,000 ha of drained minerotrophic peatlands (= fens) in NE Germany were rewetted to restore their ecological functions. Due to an extended drainage history, a re-establishment of their original state is not expected in the short-term. Elevated concentrations of dissolved organic carbon, ammonium and phosphate have been measured in the soil porewater of the upper degraded peat layers of rewetted fens at levels of one to three orders higher than the values in pristine systems; an indicator of increased microbial activity in the upper degraded soil layers. On the other hand there is evidence that the substrate availability within the degraded peat layer is lowered since the organic matter has formerly been subject to intense decomposition over the decades of drainage and intense agricultural use of the areas. Previously however, it was suggested that inhibition of hydrolytic enzymes by polyphenolic substances is suspended during aeration of peat soils mainly due to the decomposition of the inhibiting polyphenols by oxidising enzymes such as phenol oxidase. Accordingly we hypothesised a lack of enzyme inhibiting polyphenols in degraded peat soils of rewetted fens compared to less decomposed peat of more natural fens. We collected both peat samples at the soil surface (0-20 cm) and fresh roots of dominating vascular plants and mosses (as peat parent material) from five formerly drained rewetted sites and five more natural sites of NE Germany and NW Poland. Less decomposed peat and living roots were used to obtain an internal standard for polyphenol analysis and to run enzyme inhibition tests. For all samples we determined the total phenolic contents and in addition we distinguished between the contents of hydrolysable and condensed tannic substances. From a methodical perspective the advantage of internal standards compared to the commercially available standards cyanidin chloride and tannic acid became apparent. Quantification with cyanidin or tannic acid led to a considerable underestimation (up to 90%) of polyphenolic concentrations in peat soils. As hypothesised we found that highly degraded peat contains far lower levels of total polyphenolics (factor 8) and condensed tannins (factor 50) than less decomposed peat. In addition we detected large differences between different plant species with highest polyphenolic contents for the roots of Carex appropinquata that were more than 10-fold higher than Sphagnum spp. (450 mg/g dry mass vs. 39 mg/g dry mass). Despite these differences, we did not find a significant correlation between enzyme activities and peat degradation state, indicating that there is no simple linear relationship between polyphenolic contents and microbial activity.

Revealing spatial distribution of soil organic carbon contents and stocks of a disturbed bog relict by in-situ NIR and apparent EC mapping

NASA Astrophysics Data System (ADS)

Bechtold, Michel; Tiemeyer, Bärbel; Don, Axel; Altdorff, Daniel; van der Kruk, Jan; Huisman, Johan A.

2013-04-01

Previous studies showed that in-situ visible near-infrared (vis-NIR) spectroscopy can overcome the limitations of conventional soil sampling. Costs can be reduced and spatial resolution enhanced when mapping field-scale variability of soil organic carbon (SOC). Detailed maps can help to improve SOC management and lead to better estimates of field-scale total carbon stocks. Knowledge of SOC field patterns may also help to reveal processes and factors controlling SOC variability. In this study, we apply in situ vis-NIR and apparent electrical conductivity (ECa) mapping to a disturbed bog relict. The major question of this application study was how field-scale in-situ vis-NIR mapping performs for a very heterogeneous area and under difficult grassland conditions and under highly-variable water content conditions. Past intensive peat cutting and deep ploughing in some areas, in combination with a high background heterogeneity of the underlying mineral sediments, have led to a high variability of SOC content (5.6 to 41.3 %), peat layer thickness (25 to 60 cm) and peat degradation states (from nearly fresh to amorphous). Using a field system developed by Veris Technologies (Salina KS, USA), we continuously collected vis-NIR spectra at 10 cm depth (measurement range: 350 nm to 2200 nm) over an area of around 12 ha with a line spacing of about 12 m. The system includes a set of discs for measuring ECa of the first 30 and 90 cm of the soil. The same area was also mapped with a non-invasive electro-magnetic induction (EMI) setup that provided ECa data of the first 25, 50 and 100 cm. For calibration and validation of the spatial data, we took 30 representative soil samples and 15 soil cores of about 90 cm depth, for which peat thickness, water content, pore water EC, bulk density (BD), as well as C and N content were determined for various depths. Preliminary results of the calibration of the NIR spectra to the near-surface SOC contents indicate good data quality despite the challenging site conditions. Bore hole data indicates that the peat layer is characterized by lower BD, higher pore water EC, higher SOC content, and higher water contents compared to the underlying mineral sediments. This ECa contrast at the peat-sand interface is promising for using the various ECa investigation depths as predictors for peat thickness. Preliminary EMI results also show a correlation between ECa and SOC content, most strongly for the 25 cm EMI signal. We evaluate how vis-NIR and ECa data can be used in a joined approach to estimate SOC content as well as SOC stock distribution.

Subsurface structures and properties of a medium-scale peatland area by means of hydrogeophysical methods

NASA Astrophysics Data System (ADS)

Altdorff, Daniel; van der Kruk, Jan; Bechtold, Michel; Tiemeyer, Bärbel; Huismann, Sander

2013-04-01

Intact peatlands are natural sinks of climate-relevant atmospheric CO2 and they are able to store high amounts of organic carbon (C). In addition, intact peatlands are increasingly important given positive effects on biodiversity, hydrological processes and corresponding management issues. Nevertheless, large parts of peatlands in populated areas were modified by human activity during the last centuries. In Germany, more than 90% of the peatlands are drained, mainly for agricultural use. Due to the recent recognition of the positive effects of intact peatlands, there are presently several initiatives for re-wetting parts of these peatlands. However, a restoration to nearly natural conditions needs an evaluation of the current situation as well as an assessment of the restoration potential. Therefore, soil properties like peat layer thickness, bulk density and moisture content need to be known. Non-invasive hydrogeophysical methods offer the possibility for a time and cost-effective characterization of peatlands. In this study, we investigated a medium-scale peatland area (approximately 35 ha) of the 3000 ha large 'Großes Moor' peatland. We present apparent conductivity (ECa) values obtained from Electromagnetic Induction (EMI) measurements representative for three investigation depths (approximately 0.25, 0.5, and 1m). We selected zones with dissimilar ECa to identify areas where strong changes in the subsoil properties with depth are expected (i.e. shallow peat soil on top of sand). Within these areas, additional measurements were made using Ground Penetration Radar (GPR) and soil sampling was performed. In total, six 30 m long GPR profiles and corresponding common midpoint (CMP) measurements were recorded. Additionally, 15 soil cores were taken down to a depth of 0.9 m in order to obtain peat thickness, water content, pore water EC, bulk density (BD), as well as C and N content. Each core was divided into several 5 to 20 cm thick layers to obtain information on the vertical variation of these soil properties with depth. Our results indicate that the peat layer is generally characterized by lower BD, higher pore water EC, higher C content, and higher water contents compared to the underlying sand layer. Preliminary EMI results indicate a ECa - C content correlation that decreases with EMI investigation depth from 0.25 to 1 m. Regarding all soil core properties, the strongest contrast occurs at the peat-sand interface. This contrast also clearly appears in some of the GPR results. The EMI apparent conductivities are positively correlated with soil water content and peat thickness obtained from the soil cores. Preliminary GPR results confirm an increased thickness of the upper layer in areas with increased ECa values. The EMI results also reveal clear patterns linked over several fields with different land use history that represent natural structures in the subsurface.

Ecosystem state shifts during long-term development of an Amazonian peatland.

PubMed

Swindles, Graeme T; Morris, Paul J; Whitney, Bronwen; Galloway, Jennifer M; Gałka, Mariusz; Gallego-Sala, Angela; Macumber, Andrew L; Mullan, Donal; Smith, Mark W; Amesbury, Matthew J; Roland, Thomas P; Sanei, Hamed; Patterson, R Timothy; Sanderson, Nicole; Parry, Lauren; Charman, Dan J; Lopez, Omar; Valderamma, Elvis; Watson, Elizabeth J; Ivanovic, Ruza F; Valdes, Paul J; Turner, T Edward; Lähteenoja, Outi

2018-02-01

The most carbon (C)-dense ecosystems of Amazonia are areas characterized by the presence of peatlands. However, Amazonian peatland ecosystems are poorly understood and are threatened by human activities. Here, we present an investigation into long-term ecohydrological controls on C accumulation in an Amazonian peat dome. This site is the oldest peatland yet discovered in Amazonia (peat initiation ca. 8.9 ka BP), and developed in three stages: (i) peat initiated in an abandoned river channel with open water and aquatic plants; (ii) inundated forest swamp; and (iii) raised peat dome (since ca. 3.9 ka BP). Local burning occurred at least three times in the past 4,500 years. Two phases of particularly rapid C accumulation (ca. 6.6-6.1 and ca. 4.9-3.9 ka BP), potentially resulting from increased net primary productivity, were seemingly driven by drier conditions associated with widespread drought events. The association of drought phases with major ecosystem state shifts (open water wetland-forest swamp-peat dome) suggests a potential climatic control on the developmental trajectory of this tropical peatland. A third drought phase centred on ca. 1.8-1.1 ka BP led to markedly reduced C accumulation and potentially a hiatus during the peat dome stage. Our results suggest that future droughts may lead to phases of rapid C accumulation in some inundated tropical peat swamps, although this can lead ultimately to a shift to ombrotrophy and a subsequent return to slower C accumulation. Conversely, in ombrotrophic peat domes, droughts may lead to reduced C accumulation or even net loss of peat. Increased surface wetness at our site in recent decades may reflect a shift towards a wetter climate in western Amazonia. Amazonian peatlands represent important carbon stores and habitats, and are important archives of past climatic and ecological information. They should form key foci for conservation efforts. © 2017 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

Human impact on regional groundwater composition through intervention in natural flow patterns and changes in land use

NASA Astrophysics Data System (ADS)

Schot, P. P.; van der Wal, J.

1992-06-01

The relations between groundwater composition, land use, soil conditions and flow patterns on a regional scale are studied for the Gooi and Vechtstreek area in the Netherlands. This densely populated area consists of a glacier-created ridge with dry sand soils bordered by the Vecht and Eem River plains with wet peat and clay soils. R-mode factor analysis and Q-mode cluster analysis were applied to a set of 1349 groundwater analyses to determine the factors controlling groundwater composition and the main resulting water types. The results indicate that groundwater composition in the study area is affected on a regional scale by human activities through changes in land use and intervention in natural flow patterns. On the ridge, ground water is recharged by precipitation, which dissolves carbonates from the matrix of the sandy aquifer. Increased solute concentrations in shallow ground water, especially of nitrate, sulphate and potassium, indicate increased pollution resulting from urbanization and increasingly intensive agricultural activity over the past decades. In the Vecht River plain infiltration occurs as a result of drainage of polders and groundwater extraction on the ridge. Recharge occurs by precipitation and from polluted surface water to which ammonium, organic complexes and carbonic acid are added through decomposition of organic matter in the peat and clay soils. The carbonic acid results in enhanced dissolution of carbonates present in the soil and the underlying sandy aquifer. Oxygen depletion and subsequent low redox potentials result in denitrification, dissolution of manganese and iron oxides, and sulphate reduction. The flow of ground water from high-level to low-level polders causes displacement of a former stagnant brakish groundwater body under the Vecht River plain accompanied by increased mixing of fresh and brackish ground water.

Calibrated Hydrothermal Parameters, Barrow, Alaska, 2013

DOE Data Explorer

Atchley, Adam; Painter, Scott; Harp, Dylan; Coon, Ethan; Wilson, Cathy; Liljedahl, Anna; Romanovsky, Vladimir

2015-01-29

A model-observation-experiment process (ModEx) is used to generate three 1D models of characteristic micro-topographical land-formations, which are capable of simulating present active thaw layer (ALT) from current climate conditions. Each column was used in a coupled calibration to identify moss, peat and mineral soil hydrothermal properties to be used in up-scaled simulations. Observational soil temperature data from a tundra site located near Barrow, AK (Area C) is used to calibrate thermal properties of moss, peat, and sandy loam soil to be used in the multiphysics Advanced Terrestrial Simulator (ATS) models. Simulation results are a list of calibrated hydrothermal parameters for moss, peat, and mineral soil hydrothermal parameters.

Water exchange in raised bogs: revised views especially in relation to biogeochemistry

NASA Astrophysics Data System (ADS)

Sirin, Andrey; Kravchenko, Irina; Yurova, Alla; Markina, Anastasiya

2017-04-01

Raised bogs are one of the most common and exciting mire type within the boreal zone and appear in the other zones including mountain regions in the tropics. They receive water and nutrients from the atmosphere and pore water stored in their domes is spaced above the surrounding area (up to 10 m in height). Traditionally it is assumed that water flow occurs mainly in a peat layer near to the surface and water transport is negligible in deeper layers (lvanov, 1981; Ingram, 1982; etc.). The «acrotelm/catotelm» paradigm on active and inert horizons for the peat above and below the lowest water level is still widely spread in peatland hydrology. However, recent studies have shown that deep water movement is much more dynamic in raised bogs than was previously thought (Sirin et al., 1997, Reeve et al., 2000; etc.). Relying on isotope studies we conclude that all the mounded strata of the raised bogs have relatively active water exchange although water residence time changes with depth. The study included two raised bogs, representing different typical hydrological conditions (underlain by outwash sands and moraine clay) at the Zapadnaya Dvina Peatland Field Station of the Institute of Forest Science RAS located 400 km west of Moscow (56 N, 32 E). Peatlands, among which raised bogs dominate, constitute > 30% of the area, and maximum peat thickness exceeds 7 m. To evaluate water residence time in peat strata specially determined mathematical model which include the equations of water mass and tritium balance, imbedded in a conceptual framework of water dynamics within a raised bog peat body, have been developed and tested. The results from isotope studies (3H, 18O, 2H) were additionally supported by geochemical (pH, Eh, electrical conductivity) and temperature long term monitoring, as well as dissolved CO2 and CH4 monitoring within vertical profiles of the studied raised bogs (Sirin et al., 1998). Later it was also supported by microbiology data of methane cycle in the profile of peat bogs (Kravchenko, Sirin, 2007). The obtained results confirm that the hydrological stratification of peat bogs is a more complicated picture than previously thought and need to be considered.

Burnscar analysis using normalized burning ratio (NBR) index during 2015 forest fire at Merang-Kepahyang peat forest, South Sumatra, Indonesia

NASA Astrophysics Data System (ADS)

Saputra, Agus Dwi; Setiabudidaya, Dedi; Setyawan, Dwi; Khakim, M. Yusup Nur; Iskandar, Iskhaq

2017-07-01

Forest fire, classified as a natural hazard or human-induced hazard, has negative impacts on humans. These negative impacts are including economic loss, health problems, transportation disruption and land degradation or even biodiversity loss. During 2015, forest fire had occurred at the Merang-Kepahyang peat forest that has a total area of about 69.837,00 ha. In order to set a rehabilitation plan for recovering the impact of forest fire, information on the total burnscar area and severity level is required. In this study, the total burnscar area and severity level is evaluated using a calculation on the Normalized Burning Ratio (NBR) Index. The calculation is based on the Near Infra Red (NIR) and Short Wave Infra Red (SWIR) of the satellite imageries from LANDSAT. The images of pre-and post-fire are used to evaluate the severity level, which is defined as a difference in NBR Index of pre- and post-fire. It is found that about 42.906,00 ha of the total area of Merang-Kepahyang peat area have been fired in 2015. These burned area are classified into four categories, i.e., unburned, low, extreme and moderate extreme. By overlying the spatial map of burning level with other thematic maps, it is expected that strategy for rehabilitation plan can be well developed.

Layered storage of biogenic methane-enriched gas bubbles in peat: A lumped capacitance model controlled by soil structure

NASA Astrophysics Data System (ADS)

Chen, X.; Comas, X.; Binley, A. M.; Slater, L. D.

2017-12-01

Methane can accumulate in the gaseous phase in peats, and enter the atmosphere as gas bubbles with a mass flux higher than that via diffusion and plant-mediated pathways. A complete understanding of the mechanisms regulating bubble storage in peats remains incomplete. We developed a layered model to quantify the storage of gas bubbles over a peat column based on a general lumped capacitance model. This conceptual model was applied to explain the effects of peat structure on bubble storage at different depths observed in a laboratory experiment. A peat monolith was collected from the Everglades, a subtropical wetland located in Florida (USA), and kept submerged in a cuboid chamber over 102 days until gas bubble saturation was achieved. Time-lapse ground-penetrating radar (GPR) was used to estimate changes in gas content of each layer and the corresponding average dimensions of stored gas bubbles. The results highlight a hotspot layer of bubble accumulation at depths between 5 and 10 cm below the monolith surface. Bubbles in this shallow hotspot layer were larger relative to those in deeper layers, whilst the degree of decomposition of the upper layers was generally smaller than that of the lower layers based on von Post humification tests. X-ray Computer tomography (CT) was applied to resin-impregnated peat sections from different depths and the results showed that a higher porosity promotes bubbles storage. The stored gas bubbles were released by changing water levels and the air CH4 concentrations above the peat monolith were measured using a flow-through chamber system to confirm the high CH4 concentration in the stored bubbles. Our findings suggest that bubble capacitance is related to the difference in size between gas bubbles and peat pores. This work has implications for better understanding how changes in water table elevation associated with climate change and sea level rise (particularly for freshwater wetlands near coastal areas like the Everglades) may potentially alter bubble sizes, thus bubble storage in peats.

Smouldering peat fires in polluted landscapes and their impact on heavy metal mobilisation

NASA Astrophysics Data System (ADS)

Clay, Gareth; Rothwell, James; Shuttleworth, Emma

2016-04-01

Whilst wildfires are commonly viewed as a threat confined to Southern Europe, Australia, and North America, recognition of wildfire hazard in the UK has been growing in recent years. UK wildfires often occur on heathland vegetation underlain by peat. These areas can contain industrially-derived legacy pollutants, such as mercury, lead, and arsenic. Ignition of the peat can lead to long-term smouldering fires that are difficult to extinguish, leading to large-scale damage. While work on assessing post-fire damage of peatlands has focussed on carbon and nutrient dynamics, there has been little attention on the release of heavy metals following wildfires. This paper presents initial data from a preliminary study to assess heavy metal release from smouldering peat fires. A homogenised sample of peat from the Peak District National Park, UK was ignited, monitored using thermocouples and an IR camera, and left to smoulder until self-extinguished (~9 hours). Total mass loss was 61%. Samples of pre- and post-burn peat were analysed for their heavy metal concentrations using XRF, ICP-MS, and CVAFS. Sample analysis is ongoing, but initial data shows that there is a substantial (3x) relative enrichment in heavy metal concentrations in post-fire ash. This has important implications for subsequent mobilisation in the aquatic and terrestrial environments, as well as consequences for human health risk through atmospheric redistribution.

Mid- and late Holocene human impact recorded by the Coltrondo peat bog (NE Italian Alps)

NASA Astrophysics Data System (ADS)

Segnana, Michela; Poto, Luisa; Gabrieli, Jacopo; Martino, Matteo; Oeggl, Klaus; Barbante, Carlo

2016-04-01

Peat bogs are ideal archives for the study of environmental changes, whether these are natural or human induced. Indeed, receiving water and nutrients exclusively from dry and wet atmospheric depositions, they are among the most suitable matrices for palaeoenvironmental reconstruction. The present study is focused on the Eastern sector of the Italian Alps, where we sampled the Coltrondo peat bog, in the Comelico area (ca. 1800 m a.s.l.) The knowledge of the human history in this area is rather scarce: the only pieces of archaeological evidence found in this area dates back to the Mesolithic and the absence of later archaeological finds makes it difficult to reconstruct the human settlement in the valley. With the main aim to obtain information about the human settlement in that area we selected a multi-proxy approach, combining the study of biotic and abiotic sedimentary components archived in the 7900 years-peat bog record. Pollen analysis is performed along the core registering human impacts on the area from ca. 2500 cal BP, when land-use changes are well evidenced by the presence of human-related pollen and non-pollen palynomorphs (NPPs), as well as by the increase in micro-charcoal particles. Periods of increased human impact are recorded at the end of the Middle Ages and later, at the end of the 19th century. The analysis of trace elements, such as lead, is performed by means of ICP-MS technique and its enrichment factor (EF) is calculated. A first slight increase of Pb EF during Roman Times is possibly related to mining activities carried out by the Romans. Mining activities carried out in the area are registered during the Middle Ages, while the advent of the industrialization in the 20th century is marked by the highest EF values registered on the top of the core. To help and support the interpretation of geochemical data, lead isotopes ratios are also measured using ICP-MS to discriminate between natural and anthropogenic sources of lead. The 206Pb/207Pb ratio clearly records a pre-anthropogenic period from 7800 to 2500 cal BP, followed by a period in which humans impacted on the environment. During the Middle Ages the 206Pb/207Pb ratio values are attributable to mining activities, while during Modern Times they are mostly linked to industrial activities and to the introduction of leaded gasoline in Italy. The phasing out of leaded gasoline in the 1980s is also registered by the peat bog. Finally, the still on-going analysis of organic biomarkers in the peat seems to corroborate the results achieved, adding information about local disturbances on the bog. The multi-proxy approach selected for this study allows us to discriminate between different aspects of the past human presence, such as forest clearance, fires, agriculture, pasture, mining and industrial activities, giving new insights into the history of the Comelico area, still scarcely investigated.

Contemporary Mobilization of Legacy Pb Stores by DOM in a Boreal Peatland.

PubMed

Jeremiason, Jeff D; Baumann, Erin I; Sebestyen, Stephen D; Agather, Alison M; Seelen, Emily A; Carlson-Stehlin, Benjamin J; Funke, Meghan M; Cotner, James B

2018-03-20

We examined how different landscape areas in a catchment containing a northern ombrotrophic peatland and upland mineral soils responded to dramatic decreases in atmospheric deposition of lead (Pb). Pb concentrations in the outflow stream from the peatland measured from 2009-2015 indicated continued mobilization and export of Pb derived from historic inputs to the bog. In contrast, Pb concentrations in surface peat and runoff from upland mineral soils have declined in response to reductions in atmospheric deposition. Relative to the early 1980s, Pb concentrations in the streamflow decreased only ∼50%, while Pb in surface peat and upland subsurface runoff decreased by more than 90%. Water level fluctuations in the slow-accumulating peat have allowed dissolved organic matter (DOM) to continue mobilizing Pb deposited in the peatland decades earlier. Strong correlations between dissolved organic carbon (DOC) and Pb concentrations in outflow from the peatland and in bog porewaters demonstrate Pb mobility related to DOM production. Peat stores of Pb in 2016 were less than or equal to those reported in the early 1980s despite the dry mass inventory increasing by 60-80%. Much of the loss in Pb stored in peat can be accounted for by stream runoff from the peatland.

Detecting Dewatering of Peatland Pastures Using Sentinel-1 Satellite Radar Interferometry.

NASA Astrophysics Data System (ADS)

Heuff, F.; Samiei-Esfahany, S.; van Leijen, F. J.; Hanssen, R. F.

2017-12-01

The Netherlands are famous for their polders and the draining of soils to be used as pastures. Around 30% of the pastures are situated on peat soils, mostly in the western part of the Netherlands. Peat is composed of organic materials that oxidize and emit greenhouse gases when exposed to air. Oxidation of peat soils results in volume reduction and subsequent subsidence. As a result, the groundwater level rises relative to the surface. Consequently, the soil needs to be dewatered to keep it sufficiently dry for farming, resulting in more oxidation, and therefore more subsidence. This process is bound to continue until the peat soils have disappeared completely. The societal cost of land subsidence due to peat soils are estimated to be 5200 million euro for urban areas and 200 million euro for peatland pastures, for a period until 2050. Measuring the subsidence is not straightforward, if not impossible, with conventional geodetic means as soft soils make it impossible to install fixed benchmarks for repeated surveying. Also, due to the very fast temporal decorrelation over pastures, conventional InSAR approaches cannot measure a signal due to loss of coherence. Here we deploy a complete set of available SAR data from Sentinel-1, Radarsat-2 and TerraSAR-X to estimate the spatio-temporally varying subsidence signal due to the dewatering of peatland pastures over the western part of the Netherlands. We compute the InSAR coherence matrix for all possible interferometric combination, and compute an equivalent single-master stack to estimate the subsidence. Using terrain and land-use defined coherence estimation areas we optimize the phase estimation over areas severely affected by temporal decorrelation. This leads to a first estimate of deformation signals correlated with ancient shallow soil structures due to fluviatile structures. We use the methodology to investigate the effect of advanced local drainage schemes to slow down the subsidence phenomena.

Spontaneous plant colonization of brownfield soil and sludges and effects on substrate properties and pollutants mobility

NASA Astrophysics Data System (ADS)

Rocco, Claudia; Agrelli, Diana; Gonzalez, Maria Isabel; Mingo, Antonio; Motti, Riccardo; Stinca, Adriano; Coppola, Ida; Adamo, Paola

2017-04-01

This work was done on brownfield soil and sludges from a dismantled steel plant, moderately polluted by heavy metals (mainly Pb and Zn), 1) to analyzed the effects of substrate properties and environmental conditions on spontaneous vegetation; 2) to assess changes in the chemical properties of soils and sludges, with particular reference to the mobility and bioavailability of pollutants, induced by spontaneous plants revegetation. From 2006 to 2011, spontaneous plant colonization was monitored in the presence or absence of acidic peat both inside the degraded brownfield site and after transferal into a nearby Oak Park environment. During the five experimental years the vegetation growth was monitored using phytosociological method and data analyzed statistically. Both substrates, before and after plant growth, were analyzed for main chemical properties. Metals mobility and bioavailability was assessed using single (H2O; DTPA) and sequential extractions (EU-BCR). At the end of the experiment, plant ability to uptake metal was evaluated on selected species. Overall, 57 plant species grew healthily on the substrates. The combination of soil and sludges with peat resulted in an effective revegetation with a sensible increasing of plants biomass. Most of the species were found in the park (91%), showing plant colonization was mainly affected by the immediate environment rather than by substrate properties. Furthermore, after the five years, the substrate properties (pH, O.C.) were slightly affected by plant growth and, although metal pollutants in both substrates are characterized by low water solubility and DTPA availability, after plants growth an increase (even if not significant) of rhizospheric Cu, Fe, Mn and Zn solubility in H2O was detected. Metals speciation indicated a low risk of Pb and Zn mobility being either largely trapped in the mineralogical structure of oxides and silicates and occluded in easily reducible manganese or iron oxides. Restricted metal uptake and tissue accumulation by selected plants were measured, with only Daucus carota showing a higher ability to translocate metals to shoots (shoot/root metal concentration quotient >1 with peat). Water always underestimated plant uptake, while DTPA and sequential extractions better predicted Pb and Zn uptake. Phytostabilization with native plant species can be an efficient, environmentally appropriate and low cost technology for rehabilitation of industrial sites. The addition of organic matter may help the spontaneous re-vegetation and could facilitate the recovery of degraded environment. However, the changing induced by peat and plants might induced a solubilization of metal pollutants. A continuous monitoring of the potential changes of pollutants mobility-bioavailability by plants is crucial to prevent risks to the environment and human health. Key words: Heavy metals, phytoremediation, Peat addition, bioavailability, sequential extractions

Influence of forest management on the changes of organic soil properties in border part of Kragle Mokradlo Peatland (Stolowe Mountains National Park, Poland)

NASA Astrophysics Data System (ADS)

Bogacz, A.; Roszkowicz, M.

2009-04-01

SUMMARY The aim of this work was to determine the properties of organic soils modified by man, muddy and fluvial process. Peat horizons were analyzed and classified by types - and species of peat. Three profiles of shallow peat and peaty gley soils identified. Investigation showed that organic soil developed on a sandy weathered sandstone base according to oligotrophic type of sites. Organic horizons were mixed with sand and separated by sandy layers. Those soils were classified as Sapric Histosols Dystric or Sapric Gleysols Histic (WRB 2006). The throphism of organic soil in this object resulted from both natural factors and anthropo-pedogenesis. key words: peat deposit, organic soils, soil properties, muddy process, sandy layers INTRODUCTION The areas of Stolowe Mountains National Park were influenced by forestry management. Many peatlands in the Park area were drained for forestry before World War II. Several amelioration attempts were undertaken as early as in the nineteenth century. The system of forest roads were built on drained areas. The Kragle Mokradlo Peatland is located in the Skalniak plateau. The object is cut by a melioration ditch. This ditch has been recently blocked to rewet the objects. Several forest roads pass in the close neighbourhood of investigated areas. In a border part of Kragle Mokradlo Peatlands, we can observe artificial spruce habitat. Investigated object represents shallow peat soil developed on sandy basement. The early investigations showed that peaty soils were also covered by sandstone - related deposits, several dozen centimeter thick (BOGACZ 2000). Those layers was developed from sandstone weathered material transported by wind and water. The aim of presented works was to determine the stage of evolution of organic soils on the base on their morphological, physical and chemical properties. MATERIAL AND METHODS Peat soils in different locations (3 profiles, 18 samples) were selected for examination. Peat samples were collected from study areas using a 6.0 cm diameter Instorfu peat auger (HORAWSKI 1987). Soil horizons were determined on the basis of colour, degree of organic matter decomposition and the quality of vegetation remains. Cores were taken to the depth where underlying mineral material was encountered. The cores ware sectioned to subsamples at intervals at major stratigrafic breaks. Some physical, chemical properties and botanical composition of peat were determined in this material. Differentiation in botanical composition of peat was analyzed by the microscopic method and subsequently classified according to the Polish standards (Oznaczanie gatunku...1977). Peat humification degree was measured using two methods: SPEC method and half syringe method (LYNN at all. 1974). Ash content was estimated by combusting the material in a muffle furnace at 500oC for 4 hours. The texture of mineral horizons was determined using the Bouyoucos hydrometer method (GEE AND BOUNDER 1986). The specific gravity (W) and bulk density (Z) of organic soils were calculated using the following formula's (ZAWADZKI 1970): W=0.11A+1.451, (1.451) represents the specific gravity of humus, Z =0.004A+0.0913, A is a ash content and constant (0.0913) represents the bulk density of humus. The following chemical properties of organic soil horizons were analyzed: content of total carbon and nitrogen, acidity in H2O and 1mol dm-3 KCl and CECe in CH3COONH4 at pH 7. Base saturation (BS) of soil sorption complex was calculated. The soils were classified to reference groups in WRB Classification System (WRB 2006). RESULTS AND DISSCUSION Based on the cores, -the soils in the border part of Kragle Mokradlo Peatland area were classified as Sapric Histosols Dystric or Sapric Gleysols Histic (WRB 2006). Soils represented ombrogenic type of hydrological conditions. In that site, an ombrogenic type of hydrological input is the predominant mechanism of soil evolution. Soil examined in this study have developed in oligotrophic type of site. Organic soils developed on sandy weathered sandstones. The depth of organic horizons ranged from 40 to 80 cm. The object represented spruce forests habitat introduced by man. Organic horizons were separated by sandy layers. The process of sandstone weathering and forestry management changed morphological features of soils. Presently, the area is under the influence of fluvigenic type of hydrological input, too. Geobotanical analyses of peat layers indicated significant presence of preserved fragments of roots grasses, Sphagnum sp. and Bryales sp. Hemic or sapric material were usually present in organic horizons of this object. Analysis of organic horizons showed that their specific gravity was about 1.58-2.25 g cm-3, the bulk density was 0.14-0.42 g cm-3. The total porosity was in the range 82.0-91.1% and the ash content: in the range 11.74-77.96% of soil dry matter. Organic material consisting of weathered sandstone was likely to move down the profiles, increasing the concentration of sand and silt fractions in organic horizons. The similar phenomenon of residual deposits was reported by KLEMENTOWSKI (1979). The values of bulk density of peatland soils are connected with the high ash content. Ash content was different in situated layers. This is caused by the muddy and fluvial process. This situation was influenced by trophical status of this soils. The pH of sand and peat layers in a border part of Krągłe Mokradło Peatland was strongly acidic: pH H2O 2.92-3.51, pH KCl 2.38-3.07. The acidity was lower in upper horizons than in deeper ones. The ratio C/N in organic horizons ranged between 10:1 to 40:1. Low ratios of C/N in some upper horizons were probably caused by strong mineralization of organic matter. Strongly acidic soil horizons usually exhibited high cation exchange capacity (CECe). In general, the base saturated (BS) did not exceed 50%. Organic surface horizons showed higher content of potassium, calcium and magnesium than lower horizons. CONCLUSIONS Shallow organic soils occupy the ombrotrophic sites of a border part of Kragle Mokradlo Peatland. The variety of organic soil throphism in the object resulted from the placement on the base sandstone, partial mixing of soil horizons as well as from muddy and fluvial processes. Peat horizons present in the studied profiles were generally classified as hemic and sapric, sometimes as fibric. Soil horizons exhibited differed thickness and ash content. Forest management strongly changed the properties of organic soil. REFERENCES Bogacz, A. (2000). Physical properties of organic soil in Stolowe Mountains National Park (Poland). Suo 51,3; pp.105-113. Gee, G.W. and Bauder, J.W. (1986). Particle-size analysis. In: Klute, A.(ed.) Methods of Soil Analysis Part I. Agronomy series No. 9. Am. Soc. Agronomy Soil Sci. Am, Inc., Publ., Madison, WI.pp. 383-411. Horawski, M. (1987). Torfoznawstwo dla meliorantow. Pojecia podstawowe.[Peat science for melioration. Basic definitions.]. Wydawnictwo Akademii Rolniczej w Krakowie. pp.37-39.[In Polish]. Lubliner - Mianowska, K. (1951). Wskazowki do badania torfu. Metody geobotaniczne, polowe i laboratoryjne [Hints to peat research. In: Geobotanical, field and laboratory methods] Państwowe Wydawnictwo Techniczne, Katowice.pp.58-60. [In Polish]. Lynn, W.C., Mc Kinzie, W.E., Grossman, R.B. (1974). Field Laboratory Test for characterization of Histosols. In: Histosols, their characteristics, classification and use. pp. 11-20. Oznaczanie gatunku, rodzaju i typu torfu. (1977). [Peat and peat varies. Determination of classes, sort and types of peat]. Polish standard PN-76/G-02501, [Polish Normalization Commitee]. pp.1-11.[In Polish]. Word Reference Base for Soil Resources. 1998. Word Soil Resources Report, 84. FAO-ISRIC-ISSS, Rome, pp.1-88. Zawadzki, S. (1970). Relationship between the content of organic matter and physical properties of hydrogenic soils. Polish Journal of Soil Science Vol.III, 1; pp.3-9.

Potential production of palm oil-based foaming agent as fire extinguisher of peatlands in Indonesia: Literature review

NASA Astrophysics Data System (ADS)

Subekti, P.; Hambali, E.; Suryani, A.; Suryadarma, P.

2017-05-01

This study aims to analyze the potential aplication of of palm oil-based foaming agent as peat fires fighter in Indonesia. From literature review, it has been known that the foaming agent able to form foam to extinguish fire, wrap and refrigerate the burning peat. It is necessary to develop the production and application of foaming agent in Indonesia because peat fires occur almost every year that caused smoke haze. Potential raw material for the production of environmental friendly foaming agent as foam extinguishing for peat fires in Indonesia aong other is palm oil due to abundant availability, sustainable, and foam product easily degraded in the environment of the burnt areas. Production of foaming agent as fire-fighting in Indonesia is one alternative to reduce the time to control the fire and smog disaster impact. Application of palm oil as a raw material for fire-fighting is contribute to increase the value added and the development of palm oil downstream industry.

Outstanding accumulation of Sphagnum palustre in central-southern Italy

NASA Astrophysics Data System (ADS)

Casella, Laura; Zaccone, Claudio

2017-04-01

Lake Fibreno is a site where some outstanding anomalies for the flora and vegetation of the wetlands of peninsular Italy are concentrated. Here one the southernmost European population of Sphagnum palustre occurs, and is restricted on the surface of a free-floating island, i.e., a round-shaped portion of fen (with a core of Sphagnum), erratically floating on the surface of a submerged sinkhole. Geological evidences point out the existence in the area of a large lacustrine basin since Late Pleistocene. The progressive filling of the lake, caused by changing in climatic conditions and neotectonic events, resulted in the formation of peat deposits in the area, following different depositional cycles in a swampy environment. So that, the studied free-floating island, probably originated around lake margins in the waterlogged area, was somehow isolated from the bank and started to float. Once the separation occurred, sedge peat stopped to accumulate, thus enhancing the role of S. palustre as the main peat-forming plant. The vegetation occurring at the moment of the isolation of the island was a coverage of Salix cinerea/Populus tremula stands below which cushions of moss and, in a lower extent, Thelypteris palustris/Equisetum palustre accumulated resulting in the formation of 2-3 meters of peat dominated by reeds and sedges. This vegetation has been partially degraded by grazing until 1970s, while in 1980s the lake became a nature reserve. Since then, the succession could resume in a spontaneous and natural way and it was possible for the vegetation to recover to natural dynamics and growing rate. The Sphagnum tussocks were measured in an empirical way at a distance of about 60 years after the last signaling and the result was a measurement of an accretion open to about 70 cm thick. Moreover, in a recent study, a 4-m deep peat core was collected from the centre of the island and results were surprising. In fact, 14C age dating, confirmed using 210Pb and 137Cs, showed that the top 2 m of ombrotrophic Sphagnum-peat has accumulated in only ˜100 years (growth rate: ˜2 cm/yr). These values are extremely important in the evaluation scenario of the importance of these habitats especially considering that the site is currently circumscribed in a Sub-Mediterranean climate area (deciduous species-rich oak forests dominate the slopes of the catchment, and Mediterranean evergreen woody species are scattered on topographical discontinuities).

Tropical Peatland Geomorphology and Hydrology

NASA Astrophysics Data System (ADS)

Cobb, A.; Harvey, C. F.

2017-12-01

Tropical peatlands cover many low-lying areas in the tropics. In tropical peatlands, a feedback between hydrology, landscape morphology, and carbon storage causes waterlogged organic matter to accumulate into gently mounded land forms called peat domes over thousands of years. Peat domes have a stable morphology in which peat production is balanced by loss and net precipitation is balanced by lateral flow, creating a link between peatland morphology, rainfall patterns and drainage networks. We show how landscape morphology can be used to make inferences about hydrologic processes in tropical peatlands. In particular, we show that approaches using simple storage-discharge relationships for catchments are especially well suited to tropical peatlands, allowing river forecasting based on peatland morphology in catchments with tropical peatland subcatchments.

Innovative biocatalytic production of soil substrate from green waste compost as a sustainable peat substitute.

PubMed

Kazamias, Georgios; Roulia, Maria; Kapsimali, Ioanna; Chassapis, Konstantinos

2017-12-01

In the present work, a new simple and quick eco-friendly method is discussed to handle effectively the green wastes and produce a sustainable peat substitute of high quality on the large scale. Principal physicochemical parameters, i.e., temperature, moisture, specific weight, pH, electrical conductivity and, also, microorganisms, organic matter, humic substances, total Kjeldahl nitrogen and total organic carbon, C/N ratio, ash, metal content and phytotoxicity, were monitored systematically. Humic substances content values were interrelated to both C/N ratio and pH values and, similarly, bulk density, TOC, TKN, C/N, GI, ash and organic matter were found interconnected to each other. A novel biocatalyst, extremely rich in soil microorganisms, prepared from compost extracts and peaty lignite, accelerated the biotransformation. Zeolite was also employed. The compost does not demonstrate any phytotoxicity throughout the entire biotransformation process and has increased humic substances content. Both humic substances content and germination index can be employed as maturation indices of the compost. Addition of compost, processed for 60 days only, in cultivations of grass plants led to a significant increase in the stem mass and root size, annotating the significant contribution of the compost to both growth and germination. The product obtained is comparable to peat humus, useful as peat substitute and can be classified as a first class soil conditioner suitable for organic farming. Copyright © 2016 Elsevier Ltd. All rights reserved.

Annual sulfate budgets for Dutch lowland peat polders: The soil is a major sulfate source through peat and pyrite oxidation

NASA Astrophysics Data System (ADS)

Vermaat, Jan E.; Harmsen, Joop; Hellmann, Fritz A.; van der Geest, Harm G.; de Klein, Jeroen J. M.; Kosten, Sarian; Smolders, Alfons J. P.; Verhoeven, Jos T. A.; Mes, Ron G.; Ouboter, Maarten

2016-02-01

Annual sulfate mass balances have been constructed for four low-lying peat polders in the Netherlands, to resolve the origin of high sulfate concentrations in surface water, which is considered a water quality problem, as indicated amongst others by the absence of sensitive water plant species. Potential limitation of these plants to areas with low sulfate was analyzed with a spatial match-up of two large databases. The peat polders are generally used for dairy farming or nature conservation, and have considerable areas of shallow surface water (mean 16%, range 6-43%). As a consequence of continuous drainage, the peat in these polders mineralizes causing subsidence rates generally ranging between 2 and 10 mm y-1. Together with pyrite oxidation, this peat mineralization the most important internal source of sulfate, providing an estimated 96 kg SO4 ha-1 mm-1 subsidence y-1. External sources are precipitation and water supplied during summer to compensate for water shortage, but these were found to be minor compared to internal release. The most important output flux is discharge of excess surface water during autumn and winter. If only external fluxes in and out of a polder are evaluated, inputs average 37 ± 9 and exports 169 ± 17 kg S ha-1 y-1. During summer, when evapotranspiration exceeds rainfall, sulfate accumulates in the unsaturated zone, to be flushed away and drained off during the wet autumn and winter. In some polders, upward seepage from early Holocene, brackish sediments can be a source of sulfate. Peat polders export sulfate to the regional water system and the sea during winter drainage. The available sulfate probably only plays a minor role in the oxidation of peat: we estimate that this is less than 10% whereas aerobic mineralization is the most important. Most surface waters in these polders have high sulfate concentrations, which generally decline during the growing season when aquatic sediments are a sink. In the sediment, this sulfur is reduced and binds iron more strongly than phosphorus, which can be released to the overlying water and potentially fuels eutrophication. About 76% of the sampled vegetation-sites exceeded a threshold of 50 mg l-1 SO4, above which sensitive species, such as Stratiotes aloides, and several species of Potamogeton were significantly less abundant. Thus high sulfate concentrations, mainly due to land drainage and consequent mineralization, appear to affect aquatic plant community composition.

Hydrogeological and geophysical investigations to evaluate groundwater influences on GHG emissions at the national research site Skogaryd

NASA Astrophysics Data System (ADS)

Banzhaf, Stefan; Klemedtsson, Leif; Sturkell, Erik; Nyström, Elin; Barthel, Roland

2015-04-01

The overall objective of the presented study is to explore the impact of groundwater fluctuations on greenhouse gas (GHG) emissions from peatlands and in particular from drained organic soils. The hypothesis is that drained organic soils react sensitively to changing water content, i.e. that frequent changes of groundwater level enhance the emissions of GHG from these soils and thus contribute significantly to global warming. The area under investigation is based at the Skogaryd Research Catchment (within Swedish Infrastructure for Ecosystem Sciences, SITES) in western Sweden (Meyer, et al., 2013), which was recently assigned the status of a national research site by the Swedish research council (www.vr.se). Skogaryd is a unique place in Sweden for doing research on organic soils as the area was simultaneously afforested in the 1960s and the drained fertile soils have a different land-use history. The ditching for drainage purposes throughout the entire area has had and still has a huge influence on groundwater level, which in turn is assumed to trigger GHG emissions from the organic soils at Skogaryd. To address the influence of groundwater dynamics on GHG emissions in this system, a characterisation of the subsurface using electrical resistivity and Ground Penetrating Radar (GPR) measurements was carried out. These geophysical measurements were combined with drilling along them to allow for ground truthing. An average peat thickness of around 3 m was estimated for the field site. Below the peat follows a fine sand layer, which reaches a maximum thickness of around 1.0 m right at the valley borders and thins out significantly towards the middle of the valley. Below the fine sand layer follows a layer of marine clay, which extends down to the bedrock at depths between 12 and 15 m below ground surface. The results show that the peat layer in Skogaryd forms an isolated hydraulic system without interaction with deeper or regional groundwater systems. The continuously extending clay layer hinders water moving downward or upward crossing the border of peat and clay. The peat layer is a fast reacting hydraulic system that shows immediate reaction to precipitation or drought and is independent from regional groundwater levels. The study of groundwater controls on the GHG from the drained organic soils at Skogaryd can thus focus on the fast reacting peat layer. Future investigations will show if this conclusion can be generalized for similar situations in Sweden. Geophysical measurements have proved to be a valuable method for estimating the peat thickness over a large area. Meyer A, Tarvainen L, Nousratpour A, Björk RG, Ernfors M, Grelle A, Kasimir Klemedtsson Å, Lindroth A, Räntfors M, Rütting T, Wallin G, Weslien P, Klemedtsson L (2013) A fertile peatland forest does not constitute a major greenhouse gas sink. Biogeosciences 10: 7739-7758 DOI 10.5194/bg-10-7739-2013

Do storage dynamics in hydropedological units control hydrological connectivity? (Invited)

NASA Astrophysics Data System (ADS)

Tetzlaff, D.; Birkel, C.; Dick, J.; Geris, J.; Soulsby, C.

2013-12-01

In many northern landscapes, peat-dominated riparian wetlands often characterise the zone of connection between terrestrial drainage and the river network. In order to understand the relationship between connectivity and stream flow generation in a montane headwater catchment, we examined the storage dynamics and isotopic composition of soil water in major hydropedological units. These formed a classic catena sequence for northern catchments from free-draining podzols on steep upper hillslopes through to peaty gleysols in lower receiving slopes to deeper peats (Histosols) in the riparian zone. The peaty gleys and peats remained saturated throughout the year, whilst the podzols showed distinct wetting and drying cycles. In this climatic region, most precipitation events are less than 10mm in magnitude, storm runoff is mainly generated from the Histosols and Gleysols, with runoff coefficients (RCs) typically <10%. In larger events the podzolic soils become strongly connected to the saturated areas and RCs can exceed 40%. Isotopic variations in precipitation are significantly damped in the organic-rich surface horizons of the soils due to mixing with larger volumes of stored water. This damping is accentuated in the deeper soil profile and groundwater. Consequently, the isotopic composition of stream water is also damped, but the strongly reflects that of the near surface waters in the riparian peats. Old 'pre-event' water generally accounts for >80% of flow, even in large events, mainly reflecting the displacement of water stored in the riparian peats and peaty gleys. These riparian areas appear to be the dominant zone where different catchment source waters mix; acting as an 'isostat' that regulates the isotopic composition of stream waters and integrates the Transit Time Distribution (TTD) for the catchment.

Increased tree establishment in Lithuanian peat bogs--insights from field and remotely sensed approaches.

PubMed

Edvardsson, Johannes; Šimanauskienė, Rasa; Taminskas, Julius; Baužienė, Ieva; Stoffel, Markus

2015-02-01

Over the past century an ongoing establishment of Scots pine (Pinus sylvestris L.), sometimes at accelerating rates, is noted at three studied Lithuanian peat bogs, namely Kerėplis, Rėkyva and Aukštumala, all representing different degrees of tree coverage and geographic settings. Present establishment rates seem to depend on tree density on the bog surface and are most significant at sparsely covered sites where about three-fourth of the trees have established since the mid-1990s, whereas the initial establishment in general was during the early to mid-19th century. Three methods were used to detect, compare and describe tree establishment: (1) tree counts in small plots, (2) dendrochronological dating of bog pine trees, and (3) interpretation of aerial photographs and historical maps of the study areas. In combination, the different approaches provide complimentary information but also weigh up each other's drawbacks. Tree counts in plots provided a reasonable overview of age class distributions and enabled capturing of the most recently established trees with ages less than 50 years. The dendrochronological analysis yielded accurate tree ages and a good temporal resolution of long-term changes. Tree establishment and spread interpreted from aerial photographs and historical maps provided a good overview of tree spread and total affected area. It also helped to verify the results obtained with the other methods and an upscaling of findings to the entire peat bogs. The ongoing spread of trees in predominantly undisturbed peat bogs is related to warmer and/or drier climatic conditions, and to a minor degree to land-use changes. Our results therefore provide valuable insights into vegetation changes in peat bogs, also with respect to bog response to ongoing and future climatic changes. Copyright © 2014 Elsevier B.V. All rights reserved.

Survey of Hylobates agilis albibarbis in a logged peat-swamp forest: Sabangau catchment, Central Kalimantan.

PubMed

Buckley, Cara; Nekaris, K A I; Husson, Simon John

2006-10-01

Few data are available on gibbon populations in peat-swamp forest. In order to assess the importance of this habitat for gibbon conservation, a population of Hylobates agilis albibarbis was surveyed in the Sabangau peat-swamp forest, Central Kalimantan, Indonesia. This is an area of about 5,500 km(2) of selectively logged peat-swamp forest, which was formally gazetted as a national park during 2005. The study was conducted during June and July 2004 using auditory sampling methods. Five sample areas were selected and each was surveyed for four consecutive days by three teams of researchers at designated listening posts. Researchers recorded compass bearings of, and estimated distances to, singing groups. Nineteen groups were located. Population density is estimated to be 2.16 (+/-0.46) groups/km(2). Sightings occurring either at the listening posts or that were obtained by tracking in on calling groups yielded a mean group size of 3.4 individuals, hence individual gibbon density is estimated to be 7.4 (+/-1.59) individuals/km(2). The density estimates fall at the mid-range of those calculated for other gibbon populations, thus suggesting that peat-swamp forest is an important habitat for gibbon conservation in Borneo. A tentative extrapolation of results suggests a potential gibbon population size of 19,000 individuals within the mixed-swamp forest habitat sub-type in the Sabangau. This represents one of the largest remaining continuous populations of Bornean agile gibbons. The designation of the Sabangau forest as a national park will hopefully address the problem of illegal logging and hunting in the region. Further studies should note any difference in gibbon density post protection.

Local Spatial Heterogeneity of Holocene Carbon Accumulation throughout the Peat Profile of an Ombrotrophic Northern Minnesota Bog

DOE PAGES

McFarlane, Karis J.; Hanson, Paul J.; Iversen, Colleen M.; ...

2018-05-30

Here, we evaluated the spatial heterogeneity of historical carbon accumulation rates in a forested, ombrotrophic bog in Minnesota to aid understanding of responses to an ongoing decade-long warming manipulation. Eighteen peat cores indicated that the bog has been accumulating carbon for over 11,000 years, to yield 176±40 kg C m –2 to 225±58 cm of peat depth. Estimated peat basal ages ranged from 5100 to 11,100 cal BP. The long-term apparent rate of carbon accumulation over the entire peat profile was 22±2 kg C m –2yr –1. Plot location within the study area did not affect carbon accumulation rates, butmore » estimated basal ages were younger in profiles from plots closer to the bog lagg and farther from the bog outlet. In addition, carbon accumulation varied considerably over time. Early Holocene net carbon accumulation rates were 30±6 g C m –2yr –1. Around 3300 calendar BP, net carbon accumulation rates dropped to 15±8 g C m –2yr –1until the last century when net accumulation rates increased again to 74±57 g C m –2yr –1. During this period of low accumulation, regional droughts may have lowered the water table, allowing for enhanced aerobic decomposition and making the bog more susceptible to fire. These results suggest that experimental warming treatments, as well as a future warmer climate may reduce net carbon accumulation in peat in this and other southern boreal peatlands. Furthermore, our we caution against historical interpretations extrapolated from one or a few peat cores.« less

Local Spatial Heterogeneity of Holocene Carbon Accumulation throughout the Peat Profile of an Ombrotrophic Northern Minnesota Bog

DOE Office of Scientific and Technical Information (OSTI.GOV)

McFarlane, Karis J.; Hanson, Paul J.; Iversen, Colleen M.

Here, we evaluated the spatial heterogeneity of historical carbon accumulation rates in a forested, ombrotrophic bog in Minnesota to aid understanding of responses to an ongoing decade-long warming manipulation. Eighteen peat cores indicated that the bog has been accumulating carbon for over 11,000 years, to yield 176±40 kg C m –2 to 225±58 cm of peat depth. Estimated peat basal ages ranged from 5100 to 11,100 cal BP. The long-term apparent rate of carbon accumulation over the entire peat profile was 22±2 kg C m –2yr –1. Plot location within the study area did not affect carbon accumulation rates, butmore » estimated basal ages were younger in profiles from plots closer to the bog lagg and farther from the bog outlet. In addition, carbon accumulation varied considerably over time. Early Holocene net carbon accumulation rates were 30±6 g C m –2yr –1. Around 3300 calendar BP, net carbon accumulation rates dropped to 15±8 g C m –2yr –1until the last century when net accumulation rates increased again to 74±57 g C m –2yr –1. During this period of low accumulation, regional droughts may have lowered the water table, allowing for enhanced aerobic decomposition and making the bog more susceptible to fire. These results suggest that experimental warming treatments, as well as a future warmer climate may reduce net carbon accumulation in peat in this and other southern boreal peatlands. Furthermore, our we caution against historical interpretations extrapolated from one or a few peat cores.« less

Late Holocene palaeoclimate variability: The significance of bog pine dendrochronology related to peat stratigraphy. The Puścizna Wielka raised bog case study (Orawa - Nowy Targ Basin, Polish Inner Carpathians)

NASA Astrophysics Data System (ADS)

Krąpiec, Marek; Margielewski, Włodzimierz; Korzeń, Katarzyna; Szychowska-Krąpiec, Elżbieta; Nalepka, Dorota; Łajczak, Adam

2016-09-01

The results of dendrochronological and palynological analyses of subfossil pine trees occurring in the peat deposits of the Puścizna Wielka raised bog (Polish Carpathians, Southern Poland) - the only site with numerous subfossil pine trees in the mountainous regions of Central Europe presently known - indicate that the majority of the tree populations grew in the peat bog during the periods ca 5415-3940 cal BP and 3050-2560 cal BP. Several forestless episodes, dated to 5245-5155 cal BP, 4525-4395 cal BP and 3940-3050 cal BP, were preceded by tree dying-off phases caused by an extreme periodical increase in humidity and general climate cooling trends. These events are documented based on analyses of pollen and non-pollen palynomorph assemblages, dendrochronological analyses of the trees, as well as numerous radiocarbon datings of the sediment horizons occurring within the peat bog profile. The phases of germinations, and, in turn, of tree and shrub invasions of the peat bog areas have been closely connected to drying and occasional warming of the regional climate. The last of the forestless periods began about 2600 years ago and continued up to the very recent times. Currently, as a result of desiccation of the peat bog and the lowering of the groundwater level (due to improved water drainage system), pine trees have returned the peat bog again. These results demonstrate that studies of subfossil bog-pine trees are quite effective in documenting and reconstructing periods of humidity fluctuation that occurred within the Carpathian region over the last several millennia.

A deglacial and Holocene record of climate variability in south-central Alaska from stable oxygen isotopes and plant macrofossils in peat

USGS Publications Warehouse

Jones, Miriam C.; Wooller, Matthew J.; Peteet, Dorothy M.

2014-01-01

We used stable oxygen isotopes derived from bulk peat (δ18OTOM), in conjunction with plant macrofossils and previously published carbon accumulation records, in a ∼14,500 cal yr BP peat core (HT Fen) from the Kenai lowlands in south-central Alaska to reconstruct the climate history of the area. We find that patterns are broadly consistent with those from lacustrine records across the region, and agree with the interpretation that major shifts in δ18OTOM values indicate changes in strength and position of the Aleutian Low (AL), a semi-permanent low-pressure cell that delivers winter moisture to the region. We find decreased strength or a more westerly position of the AL (relatively higher δ18OTOM values) during the Bølling-Allerød, Holocene Thermal Maximum (HTM), and late Holocene, which also correspond to warmer climate regimes. These intervals coincide with greater peat preservation and enhanced carbon (C) accumulation rates at the HT Fen and with peatland expansion across Alaska. The HTM in particular may have experienced greater summer precipitation as a result of an enhanced Pacific subtropical high, a pattern consistent with modern δ18O values for summer precipitation. The combined warm summer temperatures and greater summer precipitation helped promote the observed rapid peat accumulation. A strengthened AL (relatively lower δ18OTOM values) is most evident during the Younger Dryas, Neoglaciation, and the Little Ice Age, consistent with lower peat preservation and C accumulation at the HT Fen, suggesting less precipitation reaches the leeward side of the Kenai Mountains during periods of enhanced AL strength. The peatlands on the Kenai Peninsula thrive when the AL is weak and the contribution of summer precipitation is higher, highlighting the importance of precipitation seasonality in promoting peat accumulation. This study demonstrates that δ18OTOM values in peat can be applied toward understand large-scale shifts in atmospheric circulation over millennial timescales.

A deglacial and Holocene record of climate variability in south-central Alaska from stable oxygen isotopes and plant macrofossils in peat

NASA Astrophysics Data System (ADS)

Jones, Miriam C.; Wooller, Matthew; Peteet, Dorothy M.

2014-03-01

We used stable oxygen isotopes derived from bulk peat (δ18OTOM), in conjunction with plant macrofossils and previously published carbon accumulation records, in a ˜14,500 cal yr BP peat core (HT Fen) from the Kenai lowlands in south-central Alaska to reconstruct the climate history of the area. We find that patterns are broadly consistent with those from lacustrine records across the region, and agree with the interpretation that major shifts in δ18OTOM values indicate changes in strength and position of the Aleutian Low (AL), a semi-permanent low-pressure cell that delivers winter moisture to the region. We find decreased strength or a more westerly position of the AL (relatively higher δ18OTOM values) during the Bølling-Allerød, Holocene Thermal Maximum (HTM), and late Holocene, which also correspond to warmer climate regimes. These intervals coincide with greater peat preservation and enhanced carbon (C) accumulation rates at the HT Fen and with peatland expansion across Alaska. The HTM in particular may have experienced greater summer precipitation as a result of an enhanced Pacific subtropical high, a pattern consistent with modern δ18O values for summer precipitation. The combined warm summer temperatures and greater summer precipitation helped promote the observed rapid peat accumulation. A strengthened AL (relatively lower δ18OTOM values) is most evident during the Younger Dryas, Neoglaciation, and the Little Ice Age, consistent with lower peat preservation and C accumulation at the HT Fen, suggesting less precipitation reaches the leeward side of the Kenai Mountains during periods of enhanced AL strength. The peatlands on the Kenai Peninsula thrive when the AL is weak and the contribution of summer precipitation is higher, highlighting the importance of precipitation seasonality in promoting peat accumulation. This study demonstrates that δ18OTOM values in peat can be applied toward understand large-scale shifts in atmospheric circulation over millennial timescales.

Coastal landforms and accumulation of mangrove peat increase carbon sequestration and storage

PubMed Central

Garcillán, Pedro P.

2016-01-01

Given their relatively small area, mangroves and their organic sediments are of disproportionate importance to global carbon sequestration and carbon storage. Peat deposition and preservation allows some mangroves to accrete vertically and keep pace with sea-level rise by growing on their own root remains. In this study we show that mangroves in desert inlets in the coasts of the Baja California have been accumulating root peat for nearly 2,000 y and harbor a belowground carbon content of 900–34,00 Mg C/ha, with an average value of 1,130 (± 128) Mg C/ha, and a belowground carbon accumulation similar to that found under some of the tallest tropical mangroves in the Mexican Pacific coast. The depth–age curve for the mangrove sediments of Baja California indicates that sea level in the peninsula has been rising at a mean rate of 0.70 mm/y (± 0.07) during the last 17 centuries, a value similar to the rates of sea-level rise estimated for the Caribbean during a comparable period. By accreting on their own accumulated peat, these desert mangroves store large amounts of carbon in their sediments. We estimate that mangroves and halophyte scrubs in Mexico’s arid northwest, with less than 1% of the terrestrial area, store in their belowground sediments around 28% of the total belowground carbon pool of the whole region. PMID:27035950

Estimating Carbon Stocks Along Depressional Wetlands Using Ground Penetrating Radar (GPR) in the Disney Wilderness Preserve (Orlando, Florida)

NASA Astrophysics Data System (ADS)

McClellan, M. D.; Comas, X.; Wright, W. J.; Mount, G. J.

2014-12-01

Peat soils store a large fraction of the global carbon (C) in soil. It is estimated that 95% of carbon in peatlands is stored in the peat soil, while less than 5% occurs in the vegetation. The majority of studies related to C stocks in peatlands have taken place in northern latitudes leaving the tropical and subtropical latitudes clearly understudied. In this study we use a combination of indirect non-invasive geophysical methods (mainly ground penetrating radar, GPR) as well as direct measurements (direct coring) to calculate total C stocks within subtropical depressional wetlands in the Disney Wilderness Preserve (DWP, Orlando, FL). A set of three-dimensional (3D) GPR surveys were used to detect variability of the peat layer thickness and the underlying peat-sand mix layer across several depressional wetlands. Direct samples collected at selected locations were used to confirm depth of each interface and to estimate C content in the laboratory. Layer thickness estimated from GPR and direct C content were used to estimate total peat volume and C content for the entire depressional wetland. Through the use of aerial photos a relationship between surface area along the depressional wetlands and total peat thickness (and thus C content) was established for the depressions surveyed and applied throughout the entire preserve. This work shows the importance of depressional wetlands as critical contributors of the C budget at the DWP.

Growing media [Chapter 5

Treesearch

Douglass F. Jacobs; Thomas D. Landis; Tara Luna

2009-01-01

Selecting the proper growing medium is one of the most important considerations in nursery plant production. A growing medium can be defined as a substance through which roots grow and extract water and nutrients. In native plant nurseries, a growing medium can consist of native soil but is more commonly an "artificial soil" composed of materials such as peat...

Coal in sub-Saharan-African countries undergoing desertification

NASA Astrophysics Data System (ADS)

Weaver, J. N.; Brownfield, M. E.; Bergin, M. J.

Coal has been reported in 11 of the 16 sub-Saharan countries discussed in this appraisal: Mauritania, Senegal, Mali, Niger, Benin, Nigeria, Cameroon, Central African Republic, Sudan, Ethiopia, and Somalia. No coal occurrences have been reported in Gambia, Togo, Burkina, Chad, and Djibouti but coal may be present within these countries because neighboring countries do contain coal-bearing rocks. Most of these countries are undergoing desertification or will in the near future. Wood, directly or in the form of charcoal, constitutes two-thirds of the fuel used in Africa. Destruction of forest and shrub lands for fuel is occurring at an increasing rate because of desertification and increasing energy demands. The decline in biological productivity, coupled with concentration of population in areas where water is available and crops may be grown, leads to increasing shortages of wood for fuel. Part of the present and future energy needs of the sub-Saharan region could be met by use of indigenous coal and peat. Nine sedimentary basins, completely or partially within the sub-Saharan region, have the potential of either coal and/or peat deposits of economic value: 1- Senegal Basin, 2- Taoudeni Basin and Gao Trough, 3- Niger Basin, 4- Chad Basin, 5- Chari Basin, 6- Benue Trough (Depression), 7- Sudan Trough, 8- Plateau and Rift Belt, and 9- Somali Basin. Niger and Nigeria are the only countries in sub-Saharan Africa in which coal is presently being mined as a fuel source for powerplants and domestic use. Peat occurs in the deltas, lower river, and interdunal basin areas of Senegal, Mauritania, and Sudan. Peat can be used as an alternate fuel source and is currently being tested as a soil amendment in the agricultural sector. Coal and peat exploration and development studies are urgently required and should be initiated so the coal and peat utilization potential of each country can be determined. The overall objective of these studies is to establish, within the sub-Saharan region, energy independent countries using indigenous coal and peat resources. These resources have the potential to replace wood and wood charcoal as domestic fueld in the urban centers, as well as producing electrical and industrial energy, thus reducing expensive oil imports and decreasing the rate of deforestation.

Tropical Peat and Peatland Development in the Floodplains of the Greater Pamba Basin, South-Western India during the Holocene

PubMed Central

Padmalal, Damodaran; Limaye, Ruta B.; S., Vishnu Mohan; Jennerjahn, Tim; Gamre, Pradeep G.

2016-01-01

Holocene sequences in the humid tropical region of Kerala, South-western (SW) India have preserved abundance of organic—rich sediments in the form of peat and its rapid development in a narrow time frame towards Middle Holocene has been found to be significant. The sub—coastal areas and flood plains of the Greater Pamba Basin have provided palaeorecords of peat indicating that the deposits are essentially formed within freshwater. The combination of factors like stabilized sea level and its subsequent fall since the Middle Holocene, topographic relief and climatic conditions led to rapid peat accumulation across the coastal lowlands. The high rainfall and massive floods coupled with a rising sea level must have inundated > 75% of the coastal plain land converting it into a veritable lagoon—lake system that eventually led to abrupt termination of the forest ecosystem and also converted the floodplains into peatland where accumulation of peat almost to 2.0–3.0 m thickness in coastal lowlands and river basins during the shorter interval in the Middle Holocene. Vast areas of the coastal plains of Kerala have been converted into carbon rich peatland during the Middle Holocene and transforming the entire coastal stretch and associated landforms as one of the relatively youngest peatlands in the extreme southern tip of India. Unlike the uninterrupted formation of peatlands of considerable extent during the Holocene in Southeast Asia, the south Peninsular Indian region has restricted and short intervals of peatlands in the floodplains and coastal lowlands. Such a scenario is attributed to the topographic relief of the terrain and the prevailing hydrological regimes and environmental conditions as a consequence of monsoon variability since Middle Holocene in SW India. Considering the tropical coastal lowlands and associated peatlands are excellent repositories of carbon, they are very important for regional carbon cycling and habitat diversity. The alarming rate of land modification and development is destabilizing these carbon pools resulting in large scale carbon emissions to the atmosphere and loss of low-latitude peat palaeorecords. Therefore, these palaeorecords are to be conserved and addressed for better understanding and utilizing the carbon pool for effective climate change adaptation. This communication is the first attempt of addressing the peat formation and peatland development during the Holocene from the tropical region of Peninsular India. PMID:27163658

Tropical Peat and Peatland Development in the Floodplains of the Greater Pamba Basin, South-Western India during the Holocene.

PubMed

Kumaran, Navnith K P; Padmalal, Damodaran; Limaye, Ruta B; S, Vishnu Mohan; Jennerjahn, Tim; Gamre, Pradeep G

2016-01-01

Holocene sequences in the humid tropical region of Kerala, South-western (SW) India have preserved abundance of organic-rich sediments in the form of peat and its rapid development in a narrow time frame towards Middle Holocene has been found to be significant. The sub-coastal areas and flood plains of the Greater Pamba Basin have provided palaeorecords of peat indicating that the deposits are essentially formed within freshwater. The combination of factors like stabilized sea level and its subsequent fall since the Middle Holocene, topographic relief and climatic conditions led to rapid peat accumulation across the coastal lowlands. The high rainfall and massive floods coupled with a rising sea level must have inundated > 75% of the coastal plain land converting it into a veritable lagoon-lake system that eventually led to abrupt termination of the forest ecosystem and also converted the floodplains into peatland where accumulation of peat almost to 2.0-3.0 m thickness in coastal lowlands and river basins during the shorter interval in the Middle Holocene. Vast areas of the coastal plains of Kerala have been converted into carbon rich peatland during the Middle Holocene and transforming the entire coastal stretch and associated landforms as one of the relatively youngest peatlands in the extreme southern tip of India. Unlike the uninterrupted formation of peatlands of considerable extent during the Holocene in Southeast Asia, the south Peninsular Indian region has restricted and short intervals of peatlands in the floodplains and coastal lowlands. Such a scenario is attributed to the topographic relief of the terrain and the prevailing hydrological regimes and environmental conditions as a consequence of monsoon variability since Middle Holocene in SW India. Considering the tropical coastal lowlands and associated peatlands are excellent repositories of carbon, they are very important for regional carbon cycling and habitat diversity. The alarming rate of land modification and development is destabilizing these carbon pools resulting in large scale carbon emissions to the atmosphere and loss of low-latitude peat palaeorecords. Therefore, these palaeorecords are to be conserved and addressed for better understanding and utilizing the carbon pool for effective climate change adaptation. This communication is the first attempt of addressing the peat formation and peatland development during the Holocene from the tropical region of Peninsular India.

Coal in sub-Saharan-African countries undergoing desertification

USGS Publications Warehouse

Weaver, J.N.; Brownfield, M.E.; Bergin, M.J.

1990-01-01

Coal has been reported in 11 of the 16 sub-Saharan countries discussed in this appraisal: Mauritania, Senegal, Mali, Niger, Benin, Nigeria, Cameroon, Central African Republic, Sudan, Ethiopia, and Somalia. No coal occurrences have been reported in Gambia, Togo, Burkina, Chad, and Djibouti but coal may be present within these countries because neighboring countries do contain coal-bearing rocks. Most of these countries are undergoing desertification or will in the near future. Wood, directly or in the form of charcoal, constitutes two-thirds of the fuel used in Africa. Destruction of forest and shrub lands for fuel is occurring at an increasing rate because of desertification and increasing energy demands. The decline in biological productivity, coupled with concentration of population in areas where water is available and crops may be grown, leads to increasing shortages of wood for fuel. Part of the present and future energy needs of the sub-Saharan region could be met by use of indigenous coal and peat. Nine sedimentary basins, completely or partially within the sub-Saharan region, have the potential of either coal and/or peat deposits of economic value: 1- Senegal Basin, 2- Taoudeni Basin and Gao Trough, 3- Niger Basin, 4- Chad Basin, 5- Chari Basin, 6- Benue Trough (Depression), 7- Sudan Trough, 8- Plateau and Rift Belt, and 9- Somali Basin. Niger and Nigeria are the only countries in sub-Saharan Africa in which coal is presently being mined as a fuel source for powerplants and domestic use. Peat occurs in the deltas, lower river, and interdunal basin areas of Senegal, Mauritania, and Sudan. Peat can be used as an alternate fuel source and is currently being tested as a soil amendment in the agricultural sector. Coal and peat exploration and development studies are urgently required and should be initiated so the coal and peat utilization potential of each country can be determined. The overall objective of these studies is to establish, within the sub-Saharan region, energy independent countries using indigenous coal and peat resources. These resources have the potential to replace wood and wood charcoal as domestic fueld in the urban centers, as well as producing electrical and industrial energy, thus reducing expensive oil imports and decreasing the rate of deforestation. ?? 1991.

Increase in carbon accumulation in a boreal peatland following a period of wetter climate and long-term decrease in nitrogen deposition.

PubMed

Utstøl-Klein, Simon; Halvorsen, Rune; Ohlson, Mikael

2015-06-01

Rates of peat growth and carbon (C) accumulation in a Sphagnum-dominated boreal peatland in south-east Norway were compared over two time periods each 17 yr long, that is, an earlier period from 1978 to 1995 and a recent period from 1995 to 2012. Our research was based on 109 peat cores. By using exactly the same study area and sampling protocols to obtain data for the two time periods, we were able to obtain a clear picture of the spatio-temporal patterns of peat accumulation. We show that peat growth and C accumulation were significantly higher in the recent than in the earlier time period. Interestingly, nitrogen (N) deposition was lower in the recent than in the earlier time period, while precipitation increased in the recent time period. Temperatures did not show any consistent trends over the time periods. Although our data do not allow assessment of the relative importance of declining N deposition vs increasing precipitation as drivers of peat accumulation, our results suggest that peatland C sequestration is not significantly inhibited by N pollution at current precipitation and N deposition levels. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Ecological study of peat landforms in Canada and Alaska

NASA Technical Reports Server (NTRS)

Glaser, Paul H.

1989-01-01

Over 20 percent of the land surface of Canada and Alaska is covered by peatlands, which may be defined as any waterlogged ecosystem with a minimum thickness of 20 cm of organic matter in the soil. Past investigations have demonstrated the value of aerial photographs in identifying the major vegetation types and analyzing the biotic and hydrogeologic processes that control the development of these peatlands. In the present study, LANDSAT TM imagery was used in conjunction with field studies to determine the utility of this satellite sensor for detecting these important processes. Although the vegetation landforms within these major peat basins are visible on aerial photographs, LANDSAT TM imagery provides essential new evidence for their analysis. Spectral data from the LANDSAT TM system provides: (1) synoptic views of the patterns across large portions of these peat basins, indicating important physiographic controls on peatland development, (2) more sensitive detection of the major vegetation types, allowing rapid quantitative estimates to be made of their distribution and aerial extent, (3) discrimination of bog areas with potentially rapid or slow rates of peat accumulation, (4) identification of discharge zones for groundwater, which apparently represents the most important source of alkalinity in these peat basins, and (5) detection of flow patterns in water tracks that appear nearly uniform on standard aerial photographs.

Influence of soil organic matter composition on the partition of organic compounds

USGS Publications Warehouse

Rutherford, D.W.; Chiou, C.T.; Klle, D.E.

1992-01-01

The sorption at room temperature of benzene and carbon tetrachloride from water on three high-organic-content soils (muck, peat, and extracted peat) and on cellulose was determined in order to evaluate the effect of sorbent polarity on the solute partition coefficients. The isotherms are highly linear for both solutes on all the organic matter samples, which is consistent with a partition model. For both solutes, the extracted peat shows the greatest sorption capacity while the cellulose shows the lowest capacity; the difference correlates with the polar-to-nonpolar group ratio [(O + N)/C] of the sorbent samples. The relative increase of solute partition coefficient (Kom) with a decrease of sample polar content is similar for both solutes, and the limiting sorption capacity on a given organic matter sample is comparable between the solutes. This observation suggests that one can estimate the polarity effect of a sample of soil organic matter (SOM) on Kom of various nonpolar solutes by determining the partition coefficient of single nonpolar solute when compositional analysis of the SOM is not available. The observed dependence of Kom on sample polarity is used to account for the variation of Kom values of individual compounds on different soils that results from change in the polar group content of SOM. On the assumption that the carbon content of SOM in "ordinary soils" is 53-63%, the calculated variation of Kom is a factor of ???3. This value is in agreement with the limit of variation of most Kom data with soils of relatively high SOM contents.

Peats from West Kalimantan Province, Indonesia: The Distribution, Formation, Disturbances, Utilization and Conservation

NASA Astrophysics Data System (ADS)

Anshari, G. Z.

2011-12-01

A major portion of tropical peats, approximately between 180,000 and 210,000 km2, occurs in Indonesia. Peat is a water body that preserves and stores enormous organic Carbon of dead biomass vegetation. In a natural state, peat helps to maintain Carbon balance, hydrological cycle, and supply of dissolved and particulate organic matters into adjacent waters. Peat disturbances drive the change from Carbon sink function into Carbon source. This paper aims to discuss variability of tropical peats and peat degradation in West Kalimantan Province. The discussions include extent and formation, biodiversity, Carbon and water storage, major properties, utilization, peat disturbances (i.e. logging, forest conversion, drainage affects, and recurrent peat fires), and peat conservation. Management options for reducing peat fires and developing sustainable peat utilization are also explored. Data were collected from both coastal and inland peats in West Kalimantan Province. This paper declares that degradation of tropical peats in Indonesia is strongly associated with anthropogenic fires, peat forest conversion, and logging. To reduce speeds of peat degradation, the current utilization of peats needs being more intensive than extensive, and preventing water table drop by managing excessive drainage that leads to substantial decline of moisture in the upper peat layer, which is subsequently dry and flammable.

Monitoring the effect of restoration measures in Indonesian peatlands by radar satellite imagery.

PubMed

Jaenicke, J; Englhart, S; Siegert, F

2011-03-01

In the context of the ongoing climate change discussions the importance of peatlands as carbon stores is increasingly recognised in the public. Drainage, deforestation and peat fires are the main reasons for the release of huge amounts of carbon from peatlands. Successful restoration of degraded tropical peatlands is of high interest due to their huge carbon store and sequestration potential. The blocking of drainage canals by dam building has become one of the most important measures to restore the hydrology and the ecological function of the peat domes. This study investigates the capability of using multitemporal radar remote sensing imagery for monitoring the hydrological effects of these measures. The study area is the former Mega Rice Project area in Central Kalimantan, Indonesia, where peat drainage and forest degradation is especially intense. Restoration measures started in July 2004 by building 30 large dams until June 2008. We applied change detection analysis with more than 80 ENVISAT ASAR and ALOS PALSAR images, acquired between 2004 and 2009. Radar signal increases of up to 1.36 dB show that high frequency multitemporal radar satellite imagery can be used to detect an increase in peat soil moisture after dam construction, especially in deforested areas with a high density of dams. Furthermore, a strong correlation between cross-polarised radar backscatter coefficients and groundwater levels above -50 cm was found. Monitoring peatland rewetting and quantifying groundwater level variations is important information for vegetation re-establishment, fire hazard warning and making carbon emission mitigation tradable under the voluntary carbon market or REDD (Reducing Emissions from Deforestation and Degradation) mechanism. Copyright © 2010 Elsevier Ltd. All rights reserved.

Evolution of soil and vegetation cover on the bottom of drained thermokarst lake (a case study in the European Northeast of Russia)

NASA Astrophysics Data System (ADS)

Kaverin, Dmitry; Pastukhov, Alexander

2015-04-01

The evolution of soils and landscapes has been studied in a lake bed of former thermokarst lake, which was totally drained in 1979. Melioration of thermokarst lakes was conducted experimentally and locally under Soviet economics program during 1970-s. The aim of the program was to increase in biomass productivity of virgin tundra permafrost-thermokarst sites under agricultural activities. The former thermokarst lake "Opytnoe" located in the Bolshezemelskaya Tundra, Russian European Northeast. The lake bed is covered by peat-mineral sediments, which serves as soil-forming sediments favoring subsequent permafrost aggradation and cryogenic processes as well. Initially, after drainage, swampy meadows had been developed almost all over the lake bed. Further on, succession of landscape went diversely, typical and uncommon tundra landscapes formed. When activated, cryogenic processes favored the formation of peat mounds under dwarf shrub - lichen vegetation (7% of the area). Frost cracks and peat circles affected flat mounds all over the former lake bottom. On drained peat sites, with no active cryogenic processes, specific grass meadows on Cryic Sapric Histosols were developed. Totally, permafrost-affected soils occupy 77% of the area (2011). In some part of the lake bed further development of waterlogging leads to the formation of marshy meadows and willow communities where Gleysols prevail. During last twenty years, permafrost degradation has occurred under tall shrub communities, and it will progress in future. Water erosion processes in the drained lake bottom promoted the formation of local hydrographic network. In the stream floodplain grassy willow-stands formed on Fluvisols (3% of the area). The study has been conducted under Clima-East & RFBR 14-05-31111 projects.

Active fire detection using a peat fire radiance model

NASA Astrophysics Data System (ADS)

Kushida, K.; Honma, T.; Kaku, K.; Fukuda, M.

2011-12-01

The fire fractional area and radiances at 4 and 11 μm of active fires in Indonesia were estimated using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images. Based on these fire information, a stochastic fire model was used for evaluating two fire detection algorithms of Moderate Resolution Imaging Spectroradiometer (MODIS). One is single-image stochastic fire detection, and the other is multitemporal stochastic fire detection (Kushida, 2010 - IEEE Geosci. Remote Sens. Lett.). The average fire fractional area per one 1 km2 ×1 km2 pixel was 1.7%; this value corresponds to 32% of that of Siberian and Mongolian boreal forest fires. The average radiances at 4 and 11 μm of active fires were 7.2 W/(m2.sr.μm) and 11.1 W/(m2.sr.μm); these values correspond to 47% and 91% of those of Siberian and Mongolian boreal forest fires, respectively. In order to get false alarms less than 20 points per 106 km2 area, for the Siberian and Mongolian boreal forest fires, omission errors (OE) of 50-60% and about 40% were expected for the detections by using the single and multitemporal images, respectively. For Indonesian peat fires, OE of 80-90% was expected for the detections by using the single images. For the peat-fire detections by using the multitemporal images, OE of about 40% was expected, provided that the background radiances were estimated from past multitemporal images with less than the standard deviation of 1K. The analyses indicated that it was difficult to obtain sufficient active-fire information of Indonesian peat fires from single MODIS images for the fire fighting, and that the use of the multitemporal images was important.

Testate amoebae analysis in the peat deposits of the swamp Dolgon’koye in the south of Western Siberia and peatland paleohydrology for last 3100 years

NASA Astrophysics Data System (ADS)

Kurina, Irina V.; Blyakharchuk, Tatiana A.

2018-03-01

Our research is devoted to paleohydrological reconstruction in the swamp located in the river valley on the piedmont of the Altai Mountains in the south of Western Siberia. The reconstruction was carried out based on rhizopod analysis for the last 3100 cal yr. A large amount of different testate amoebae was found in the peat. Total 64 testate amoebae taxa were recorded in the peat core with the most abundant being: Trinema lineare, Centropyxis aculeata, C. aerophila, Euglypha rotunda, Cryptodifflugia sp. Decrease of surface wetness in the swamp are observed 2280, 2140, 1900–600 cal yr BP and increase – in 2700, 2500–1900, 230–215 cal yr BP. The results of our reconstruction of the swamp paleohydrology agrees well with the paleoclimatic data obtained earlier for the central area of the south of Western Siberia Plain. It indicates a high sensitivity of the swamp to climatic changes in the Holocene. The rhizopod analysis proved to be very effective when used for paleohydrology reconstruction in minerotrophic peat.

DOC export from a peat extraction site in transition to managed restoration - preliminary results of a long-term research project

NASA Astrophysics Data System (ADS)

Rüggen, Norman; Kutzbach, Lars; Kopelke, Susanne; Pfeiffer, Eva-Maria

2013-04-01

Peatlands play a major role in the global cycles of water and carbon. Budgeting carbon fluxes of temperate man-managed peatlands is limited by few available data. The main carbon compounds exported from such sites are CO2, CH4 and laterally exported C compounds (dissolved organic carbon (DOC) and gases). Without reliable estimates of laterally exported carbon from managed peatlands, overall carbon balances of such geoecosystems remain obscure. The Himmelmoor peatland in Schleswig-Holstein is subject to horticultural peat extraction in transition towards managed restoration. One-third of 130 ha of peatland area are already subject to managed restoration, the remaining part is still intensively used as a peat extraction site. Surface water discharge rates are measured by a water head sensor in combination with a rectangular-shaped weir. An October-November data set (54 days period, 2012) shows a distinct base-flow and precipitation-dependent discharge peaks, which were up to five times higher than the base-flow. The observations indicate a poor water storing capacity of the intensively used areas. During this first observation period, almost 65,000 tons of peatland-DOC-bearing water have been discharged into the adjacent river system. DOC concentrations in the discharge water have been measured every 6-12 days with a Total Carbon Analyzer TOC-L (Shimadzu, Japan). Additionally, a field spectrophotometer (spectro::lyser,s-can, Austria) has been employed, for measuring quasi-continuous concentrations of DOC. During the 54 day period, approximately 1.75 g DOC m-2 (or about 1750 kg DOC km-2) has been laterally exported from the peatland. Average DOC concentration was 35.1 ± 4 g l-1. These values range in the same order of magnitude that have been published from managed UK peatlands (Armstrong et al., 2010; Wilson et al., 2011). Preliminary data evaluation of the in-situ field spectrophotometer show that DOC concentrations of discharge water varied up to 1.5 mg L-1 in less than six hours and up to about 3 mg L-1 in 36 hours. The described recently established hydrological measurements are planned to be continued for the next ten years in combination with continuous eddy covariance measurements of land-atmosphere fluxes of Water, CO2 and CH4. This long-term monitoring of lateral and vertical exchange fluxes will serve as a basis for evaluating the success of the peatland restoration with respect to biogeochemical cycling and greenhouse gas budgets. Literature Armstrong, A., Holden, J., Kay, P., Francis, B., Foulger, M., Gledhill, S., McDonald, A., Walker, A., 2010. The impact of peatland drain-blocking on dissolved organic carbon loss and discolouration of water; results from a national survey. Journal of Hydrology 381, 112-120. Wilson, L., Wilson, J., Holden, J., Johnstone, I., Armstrong, A., Morris, M., 2011. Ditch blocking, water chemistry and organic carbon flux: Evidence that blanket bog restoration reduces erosion and fluvial carbon loss. Science of the Total Environment 409, 2010-2018.

Stratigraphic response of salt marshes to slow rates of sea-level change

NASA Astrophysics Data System (ADS)

Daly, J.; Bell, T.

2006-12-01

Conventional models of salt-marsh development show an idealized spatial relationship between salt-marsh floral and foraminiferal zones, where the landward margin of the marsh gradually migrates inland in response to sea-level rise. This model predicts that transgression will result in persistent and possibly expanded salt marshes at the surface, depending on a variety of factors including sediment supply, hydrologic conditions, tidal range, and rate of sea-level rise. However, in areas with abundant sediment supply and slow rates of sea- level rise, the extent of back-barrier salt marshes may decline over time as the barrier-spits mature. Sea level around the northeast coast of Newfoundland is rising at a very slow rate during the late Holocene (<0.5 mm/yr). Sandy barrier-spits and tombolos are common coastal features, but salt marshes are rare. The generalized stratigraphy of dutch cores collected in back-barrier settings in this region is a surface layer of sphagnum peat with abundant woody roots, underlain by sedge-dominated peat that transitions gradually to a thin layer of Juncus sp. peat with agglutinated foraminifera, dominantly Jadammina macrescens and Balticammina pseudomacrescens. These basal peats are interpreted as salt-marsh peats, characterized by the presence of foraminifera that are absent in overlying peat units. This sequence indicates that salt marshes developed in back-barrier environments during the initial stages of barrier progradation, then gradually transitioned to environments increasingly dominated by freshwater flora. These transitions are interpreted to reflect the progradation of the spit, decreased tidal exchange in the back-barrier, and increased influence of freshwater streams discharging into the back-barrier setting. Decreased marine influence on the back-barrier environment leads to a floral and faunal shift associated with a regressive stratigraphy in an area experiencing sea-level rise. For studies of Holocene sea-level change requiring salt-marsh stratigraphic records, it is necessary to account for changing micro-environments to locate sites appropriate for study; salt marshes may play an important role in defining the record, but may not exist at the surface to guide investigation.

Temperature-Induced Increase in Methane Release from Peat Bogs: A Mesocosm Experiment

PubMed Central

van Winden, Julia F.; Reichart, Gert-Jan; McNamara, Niall P.; Benthien, Albert; Damsté, Jaap S. Sinninghe.

2012-01-01

Peat bogs are primarily situated at mid to high latitudes and future climatic change projections indicate that these areas may become increasingly wetter and warmer. Methane emissions from peat bogs are reduced by symbiotic methane oxidizing bacteria (methanotrophs). Higher temperatures and increasing water levels will enhance methane production, but also methane oxidation. To unravel the temperature effect on methane and carbon cycling, a set of mesocosm experiments were executed, where intact peat cores containing actively growing Sphagnum were incubated at 5, 10, 15, 20, and 25°C. After two months of incubation, methane flux measurements indicated that, at increasing temperatures, methanotrophs are not able to fully compensate for the increasing methane production by methanogens. Net methane fluxes showed a strong temperature-dependence, with higher methane fluxes at higher temperatures. After removal of Sphagnum, methane fluxes were higher, increasing with increasing temperature. This indicates that the methanotrophs associated with Sphagnum plants play an important role in limiting the net methane flux from peat. Methanotrophs appear to consume almost all methane transported through diffusion between 5 and 15°C. Still, even though methane consumption increased with increasing temperature, the higher fluxes from the methane producing microbes could not be balanced by methanotrophic activity. The efficiency of the Sphagnum-methanotroph consortium as a filter for methane escape thus decreases with increasing temperature. Whereas 98% of the produced methane is retained at 5°C, this drops to approximately 50% at 25°C. This implies that warming at the mid to high latitudes may be enhanced through increased methane release from peat bogs. PMID:22768100

Holocene climate variability in the western Mediterranean through a multiproxy analysis from Padul peat bog (Sierra Nevada, Spain)

NASA Astrophysics Data System (ADS)

Ramos-Román, María J.; Jiménez-Moreno, Gonzalo; Camuera, Jon; García-Alix, Antonio; Anderson, R. Scott; Jiménez-Espejo, Francisco J.; Sachse, Dirk

2017-04-01

The Iberian Peninsula, located in the Mediterranean area, is an interesting location for paleoclimate studies due to its geographic situation between arid and humid climates. Sediments from peat bogs and lakes from Sierra Nevada, in southeastern Iberian Peninsula, have been very informative in terms of how vegetation and wetland environments were impacted by Holocene climate change. These studies are essential if we want to understand the past climate change in the area, which is the key to identify the possible environmental response of the Sierra Nevada ecosystems to future climate scenarios. Padul basin, located in the southwest of the Sierra Nevada mountain range, contains a ca. 100 m-thick peat bog sedimentary sequence that was deposited during the past 1 Ma making this area interesting for paleoenvironmental and paleoclimatic reconstructions. A new 43 m-long sedimentary record has recently been retrieved from the Padul peat bog. In this study we have developed a multiproxy analysis of the Holocene part of the Padul-15-05 core including pollen analysis, XRF-core scanner, magnetic susceptibility and organic geochemistry, supported by an age control based on AMS radiocarbon dates, providing with information about vegetation and climate variability during the past 9.9 cal ka BP. This multiproxy reconstruction of the Padul-15-05 evidences the Mediterranean as a sensitive area with respect to global-scale climate system, showing relevant climate episodes such as the ca. 8, 7.5, 6.5 and 5.5 cal ka BP events during the early and middle Holocene. The trend to aridification to the late Holocene is interrupted by more arid and humid periods as the Iberian Roman Humid Period (from ca. 3 to 1.6 cal ka BP), the Dark Ages (from ca. 1.5 to 1.1 cal ka BP), the Medieval Climate Anomaly (from ca. 1.1 to 1.3 cal ka BP) and the Little Ice Age period (from ca. 500 to 100 cal yr BP).

Fourth technical contractors' conference on peat

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1981-01-01

This conference reported the status of the US Department of Energy Peat Program. The papers presented dealt with peat dewatering, international peat programs, environmental and socio-economic factors, peat gasification, peat harvesting, and the state peat surveys for 14 states. Separate abstracts were prepared for the individual papers. (CKK)

Spatial patterns of denitrification and its functional genes in peatlands

NASA Astrophysics Data System (ADS)

Mander, Ülo; Ligi, Teele; Truu, Marika; Truu, Jaak; Pärn, Jaan; Egorov, Sergey; Järveoja, Järvi; Vohla, Christina; Maddison, Martin; Soosaar, Kaido; Oopkaup, Kristjan; Teemusk, Alar; Preem, Jens-Konrad; Uuemaa, Evelyn

2014-05-01

This study is aimed to analyse relationships between the environmental factors and the spatial distribution of the main functional genes nirS, nirK, and nosZ regulating the denitrification process. Variations in hydrological regime, soil temperature and peat quality have been taken into the consideration at both local and global scale. Measurements of greenhouse gas (GHG) emissions using static chambers, groundwater analysis, gas and peat sampling for further laboratory analysis has been conducted in various peatlands in Iceland (two study areas, 2011), Transylvania/Romania (2012), Santa Catarina/Brazil (2012), Quebec/Canada (2012), Bashkortostan/Russian Federation (two study areas, 2012), Sichuan/China (2012), Estonia (two study areas, 2012), Florida/USA (2013, Sologne/France (2013), Jugra in West Siberia/Russia (2013), Uganda (2013), French Guyana (two study areas, 2013), Tasmania (two study areas, 2014) and New Zealand (two study areas, 2014). In each study area at least 2 transects along the groundwater depth gradient, one preferably in undisturbed, another one in drained area, and at least 3 rows of sampling sites (3-5 replicate chambers and 1 piezometer and soil sampling plot in each) in both has been established for studies. In each transect GHG emission was measured during 2-3 days in at least 5 sessions. In addition, organic sediments from the artificial riverine wetlands in Ohio/USA in 2009 and relevant gas emission studies have been used in the analyses. In the laboratories of Estonian University of Life Sciences and the University of Tartu, the peat chemical quality (pH, N, P, C, NH4, NO3) and N2O, CO2, and CH4 concentration in gas samples (50mL glass bottles and exetainers) were analysed. The peat samples for further pyrosequencing and qPCR analyses are stored in fridge by -22oC. This presentation will consider the variation of GHG emissions and hydrological conditions in the study sites. In addition, several selected biophysical factors will be taken into account. Further study will include peatland sites in Montana/USA, Columbia (Andes), Tierra del Fuego/Argentina, Pyrenees/Spain, Savo/Finland, the Netherlands, Okawango/Botswana, Heilongjiang/China, and Kamchatka/Russian Federation. Also, additional analysis will be conducted on the relationships between the intensity of CH4 emissions and methanogenesis regulating functional genes mcrA, pmoA, and dsrAB.

High soil solution carbon und nitrogen concentrations in a drained Atlantic bog are reduced to natural levels by 10 yr of rewetting

NASA Astrophysics Data System (ADS)

Frank, S.; Tiemeyer, B.; Gelbrecht, J.; Freibauer, A.

2013-10-01

Artificial drainage of peatlands causes dramatic changes in the release of greenhouse gases and in the export of dissolved carbon (C) and nutrients to downstream ecosystems. Rewetting anthropogenically altered peatlands offers a possibility to reduce nitrogen (N) and C losses. In this study, we investigate the impact of drainage and rewetting on the cycling of dissolved C and N as well as on dissolved gases over a period of 1 yr and 4 month, respectively. The peeper technique was used to receive a high vertical sampling resolution. Within one Atlantic bog complex a near natural site, two drained grasslands sites with different mean water table positions, and a former peat cutting area rewetted 10 yr ago were chosen. Our results clearly indicate that drainage increased the concentration of dissolved organic carbon (DOC), ammonia, nitrate and dissolved organic nitrogen (DON) compared to the near natural site. Drainage depth further determined the release and therefore the concentration level of DOC and N species, but the biochemical cycling and therefore dissolved organic matter (DOM) quality and N species composition were unaffected. Thus, especially deep drainage can cause high DOC losses. In general, DOM at drained sites was enriched in aromatic moieties as indicated by SUVA280 and showed a higher degradation status (lower DOC to DON ratio) compared to the near natural site. At the drained sites, equal C to N ratios of uppermost peat layer and DOC to DON ratio of DOM in soil solution suggest that the uppermost degraded peat layer is the main source of DOM. Nearly constant DOC to DON ratios and SUVA280 values with depth furthermore indicated that DOM moving downwards through the drained sites remained largely unchanged. DON and ammonia contributed most to the total dissolved nitrogen (TN). The subsoil concentrations of nitrate were negligible due to strong decline in nitrate around mean water table depth. Methane production during the winter months at the drained sites moved downwards to areas which were mostly water saturated over the whole year (>40 cm). Above these depths, the recovery of the water table in winter months led to the production of nitrous oxide around mean water table depth at drained sites. 10 yr after rewetting, the DOM quality (DOC to DON ratio and SUVA280) and quantity were comparable to the near natural site, indicating the re-establishment of mostly pristine biochemical processes under continuously water logged conditions. The only differences occur in elevated dissolved methane and ammonia concentrations reflecting the former disturbance by drainage and peat extraction. Rewetting via polder technique seems to be an appropriate way to revitalize peatlands on longer timescales and to improve the water quality of downstream water bodies.

Classifying and mapping wetlands and peat resources using digital cartography

USGS Publications Warehouse

Cameron, Cornelia C.; Emery, David A.

1992-01-01

Digital cartography allows the portrayal of spatial associations among diverse data types and is ideally suited for land use and resource analysis. We have developed methodology that uses digital cartography for the classification of wetlands and their associated peat resources and applied it to a 1:24 000 scale map area in New Hampshire. Classifying and mapping wetlands involves integrating the spatial distribution of wetlands types with depth variations in associated peat quality and character. A hierarchically structured classification that integrates the spatial distribution of variations in (1) vegetation, (2) soil type, (3) hydrology, (4) geologic aspects, and (5) peat characteristics has been developed and can be used to build digital cartographic files for resource and land use analysis. The first three parameters are the bases used by the National Wetlands Inventory to classify wetlands and deepwater habitats of the United States. The fourth parameter, geological aspects, includes slope, relief, depth of wetland (from surface to underlying rock or substrate), wetland stratigraphy, and the type and structure of solid and unconsolidated rock surrounding and underlying the wetland. The fifth parameter, peat characteristics, includes the subsurface variation in ash, acidity, moisture, heating value (Btu), sulfur content, and other chemical properties as shown in specimens obtained from core holes. These parameters can be shown as a series of map data overlays with tables that can be integrated for resource or land use analysis.

Comparison of the petrography, palynology and paleobotany of the Stockton coal bed, West Virginia and implications for paleoenvironmental interpretations

USGS Publications Warehouse

Pierce, B.S.; Stanton, R.W.; Eble, C.F.

1993-01-01

The Stockton coal bed (Middle Pennsylvanian) is a relatively high ash coal composed primarily of moderately thin banded, sparsely thin banded, and nonbanded coal (splint and cannel coal). Comparisons of petrographic, palynologic, and paleobotanic data gathered from the same sample sets from a single column of the Stockton coal bed indicate that compositional correspondences among the sets exist regardless of coal type. Some correspondences are believed to exist because of original plant constituents and others because of the paleoenvironment of peat formation. Using some combination of these data is critical when interpreting paleoenvironmental conditions because (1) a direct correspondence is lacking between many of the data and (2) each of the three data sets provides a unique and important perspective on the paleomire. The Stockton paleomire in the area of this study supported a diverse flora that consisted of both small and arboreous lycopsids, small ferns and tree ferns, calamites, cordaites, and pteridosperms. There appear to have been two successions of Lycospora spore-dominated, vitrinite-rich, liptinite-poor peat formation, which were followed by inertinite-rich peat formation marked by a tree fern-dominant spore assemblage and abundant unidentifiable plant tissues. These are interpreted to be two water-laden or topogenous peat formational stages followed by slightly domed, better drained peat formation. ?? 1993.

How do peat type, sand addition and soil moisture influence the soil organic matter mineralization in anthropogenically disturbed organic soils?

NASA Astrophysics Data System (ADS)

Säurich, Annelie; Tiemeyer, Bärbel; Don, Axel; Burkart, Stefan

2017-04-01

Drained peatlands are hotspots of carbon dioxide (CO2) emissions from agriculture. As a consequence of both drainage induced mineralization and anthropogenic sand mixing, large areas of former peatlands under agricultural use contain soil organic carbon (SOC) at the boundary between mineral and organic soils. Studies on SOC dynamics of such "low carbon organic soils" are rare as the focus of previous studies was mainly either on mineral soils or "true" peat soil. However, the variability of CO2 emissions increases with disturbance and therefore, we have yet to understand the reasons behind the relatively high CO2 emissions of these soils. Peat properties, soil organic matter (SOM) quality and water content are obviously influencing the rate of CO2 emissions, but a systematic evaluation of the hydrological and biogeochemical drivers for mineralization of disturbed peatlands is missing. With this incubation experiment, we aim at assessing the drivers of the high variability of CO2 emissions from strongly anthropogenically disturbed organic soil by systematically comparing strongly degraded peat with and without addition of sand under different moisture conditions and for different peat types. The selection of samples was based on results of a previous incubation study, using disturbed samples from the German Agricultural Soil Inventory. We sampled undisturbed soil columns from topsoil and subsoil (three replicates of each) of ten peatland sites all used as grassland. Peat types comprise six fens (sedge, Phragmites and wood peat) and four bogs (Sphagnum peat). All sites have an intact peat horizon that is permanently below groundwater level and a strongly disturbed topsoil horizon. Three of the fen and two of the bog sites have a topsoil horizon altered by sand-mixing. In addition the soil profile was mapped and samples for the determination of soil hydraulic properties were collected. All 64 soil columns (including four additional reference samples) will be installed in a microcosm system under a constant temperature of 10°C. The water-saturated soil columns will be drained via suction plates at the bottom of the columns by stepwise increase of the suction. The head space of the soil columns will be permanently flushed with moistened synthetic air and CO2 concentrations will be measured via online gas chromatography. First results will be presented.

A Deglacial and Holocene Record of Climate Variability in South-Central Alaska from Stable Oxygen Isotopes and Plant Macrofossils in Peat

NASA Technical Reports Server (NTRS)

Jones, Miriam C.; Wooller, Matthew; Peteet, Dorothy M.

2014-01-01

We used stable oxygen isotopes derived from bulk peat (delta-O-18(sub TOM) in conjunction with plant macrofossils and previously published carbon accumulation records, in a approximately14,500 cal yr BP peat core (HT Fen) from the Kenai lowlands in south-central Alaska to reconstruct the climate history of the area. We find that patterns are broadly consistent with those from lacustrine records across the region, and agree with the interpretation that major shifts in delta-O-18(sub TOM) values indicate changes in strength and position of the Aleutian Low (AL), a semi-permanent low-pressure cell that delivers winter moisture to the region. We find decreased strength or a more westerly position of the AL (relatively higher delta-O-18(sub TOM) values) during the Bolling-Allerod, Holocene Thermal Maximum (HTM), and late Holocene, which also correspond to warmer climate regimes. These intervals coincide with greater peat preservation and enhanced carbon (C) accumulation rates at the HT Fen and with peatland expansion across Alaska. The HTM in particular may have experienced greater summer precipitation as a result of an enhanced Pacific subtropical high, a pattern consistent with modern delta-O-18 values for summer precipitation. The combined warm summer temperatures and greater summer precipitation helped promote the observed rapid peat accumulation. A strengthened AL (relatively lower delta-O-18(sub TOM) values) is most evident during the Younger Dryas, Neoglaciation, and the Little Ice Age, consistent with lower peat preservation and C accumulation at the HT Fen, suggesting less precipitation reaches the leeward side of the Kenai Mountains during periods of enhanced AL strength. The peatlands on the Kenai Peninsula thrive when the AL is weak and the contribution of summer precipitation is higher, highlighting the importance of precipitation seasonality in promoting peat accumulation. This study demonstrates that delta-O-18(sub TOM) values in peat can be applied toward understand large-scale shifts in atmospheric circulation over millennial timescales.

Vertical Stratification of Peat Pore Water Dissolved Organic Matter Composition in a Peat Bog in Northern Minnesota: Pore Water DOM composition in a peat bog

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tfaily, Malak M.; Wilson, Rachel M.; Cooper, William T.

We characterized dissolved organic matter (DOM) composition throughout the peat column at the Marcell S1 forested bog in northern Minnesota and tested the hypothesis that redox oscillations associated with cycles of wetting and drying at the surface of the fluctuating water table correlate with increased carbon, sulfur and nitrogen turn over. We found significant vertical stratification of DOM molecular composition and EEM-PARAFAC components within the peat column. In particular the intermediate depth zone (~ 50 cm) was identified as a zone where maximum decomposition and turnover is taking place. Surface DOM was dominated by inputs from surface vegetation. The intermediate-depthmore » zone was an area of high organic matter reactivity and increased microbial activity with diagenetic formation of many unique compounds, among them polycyclic aromatic compounds (PAC) that contain both nitrogen and sulfur heteroatoms. These compounds have been previously observed in coal-derived compounds and were assumed to be responsible for coal's biological activity. Biological processes triggered by redox oscillations taking place at the intermediate depth zone of the peat profile at the S1 bog are assumed to be responsible for the formation of these heteroatomic PACs in this system. Alternatively these compounds could stem from black carbon and nitrogen derived from fires that have occurred at the site in the past. Surface and deep DOM exhibited more similar characteristics, compared to the intermediate-depth zone, with the deep layer exhibiting greater input of microbially degraded organic matter than the surface suggesting that the entire peat profile consists of similar parent material at different degrees of decomposition and that lateral and vertical advection of pore water from the surface to the deeper horizons is responsible for such similarities. Our findings suggest that molecular composition of DOM in peatland pore water is dynamic and is a function of ecosystem activity, water table and redox oscillation and porewater advection.« less

Trace metal mobilization by organic soil amendments: insights gained from analyses of solid and solution phase complexation of cadmium, nickel and zinc.

PubMed

Welikala, Dharshika; Hucker, Cameron; Hartland, Adam; Robinson, Brett H; Lehto, Niklas J

2018-05-01

The accumulation of Cd in soils worldwide has increased the demand for methods to reduce the metal's plant bioavailability. Organic matter rich soil amendments have been shown to be effective in achieving this. However, it is not known how long these amendments can retain the Cd, and whether dissolved organic matter (DOM) released from them can enhance the metal's mobility in the environment. In this study we sought to test the Cd binding capacity of various organic soil amendments, and evaluate differences in characteristics of the DOM released to see if they can explain the lability of the Cd-DOM complexes. We collected ten organic soil amendments from around New Zealand: five different composts, biosolids from two sources, two types of peat and spent coffee grounds. We characterised the amendments' elemental composition and their ability to bind the Cd. We then selected two composts and two peats for further tests, where we measured the sorption of Ni or Zn by the amendments. We analysed the quality of the extracted DOM from the four amendments using 3D Excitation Emission Matrix analysis, and tested the lability of the metal-DOM complexes using an adapted diffusive gradients in thin-films (DGT) method. We found that composts bound the most Cd and that the emergent Cd-DOM complexes were less labile than those from the peats. Ni-DOM complexes were the least labile. The aromaticity of the extracted DOM appears to be an important factor in determining the lability of Ni complexes, but less so for Zn and Cd. Copyright © 2018 Elsevier Ltd. All rights reserved.

The effects of fire on greenhouse gas fluxes from mosses and lichen patches in the Yukon Kuskokwim Delta, AK.

NASA Astrophysics Data System (ADS)

Navarro-Perez, E.; Natali, S.; Schade, J. D.; Holmes, R. M.; Mann, P. J.

2017-12-01

Climate change has altered patterns of temperature, emissions of greenhouse gases and increased fire frequencies, especially in the Artic. Until recently, the Arctic has been a carbon (C) sink, but have begun releasing C in recent years, likely in response to warming temperatures, permafrost thaw and resulting changes in microbial processes. In addition, increases in fire frequency and intensity are changing vegetation patterns, particularly the relative importance of mosses and lichens. These changes alter soil temperatures, nutrient availability, and moisture, consequently affecting microbial processes and the release of greenhouse gases (GHG) such as N2O, CO2 and CH4. The objective of this research was to understand how recent fires in the Yukon-Kuskokwim River Delta in southwest Alaska are affecting the emission of GHGs from peat plateau soils. We hypothesized that the presence of mosses and lichen would change soil moisture and temperature, leading to changes in GHG production after fire. We also hypothesized that fire would increase soil nutrient availability, which would increase microbial process rates and GHG emissions. To test these hypotheses, we measured N2O, CH4 and CO2 fluxes from moss and lichen patches in three burned and unburned areas and collected soil cores for analyses of gravimetric soil moisture, carbon and nitrogen concentrations, and N mineralization rates. Soil temperatures were measured in the field with a thermocouple. Results demonstrated low but measurable CH4 emissions from all patches, suggesting peat plateaus in the YK Delta may be CH4 sources. In addition, CO2 emissions were higher in soils under lichen patches in burned areas than unburned controls. Finally, results suggest that burned areas have higher concentrations of extractable NH4 and NO3, and that increased N may be increasing soil respiration.

Pathways of nutrient loading and impacts on plant diversity in a New York peatland

USGS Publications Warehouse

Drexler, J.Z.; Bedford, B.L.

2002-01-01

Nutrient loading is a subtle, yet serious threat to the preservation of high diversity wetlands such as peatlands. Pathways of nutrient loading and impacts on plant diversity in a small peatland in New York State, USA were determined by collecting and analyzing a suite of hydrogeological, hydro-chemical, soil, and vegetation data. Piezometer clusters within an intensive network constituted hydro-chemical sampling points and focal points for randomly selected vegetation quadrats and soil-coring locations. Hydrogeological data and nutrient analyses showed that P and K loading occurred chiefly by means of overland flow from an adjacent farm field, whereas N loading occurred predominantly through ground-water flow from the farm field. Redundancy analysis and polynomial regression showed that nutrients, particularly total P in peat, total K in peat, extractable NH4-N, and NO3-N flux in ground water, were strongly negatively correlated with plant diversity measures at the site. No other environmental variables except vegetation measures associated with eutrophication demonstrated such a strong relationship with plant diversity. Nitrate loading over 4 mg m -2 day-1 was associated with low plant diversity, and Ca fluxes between 80 and 130 mg m-2 day-1 were associated with high plant diversity. Areas in the site with particularly low vascular plant and bryophyte species richness and Shannon-Wiener diversity (H') occurred adjacent to the farm field and near a hillside spring. High H' and species richness of vascular plants and bryophytes occurred in areas that were further removed from agriculture, contained no highly dominant vegetation, and were situated directly along the ground-water flow paths of springs. These areas were characterized by relatively constant water levels and consistent, yet moderate fluxes of base cations and nutrients. Overall, this study demonstrates that knowledge of site hydrogeology is crucial for determining potential pathways of nutrient loading and for developing relationships between nutrient inflows and wetland plant diversity. ?? 2002, The Society of Wetland Scientists.

Changes in carbon fractions during composting and maturation of organic wastes

NASA Astrophysics Data System (ADS)

Garcia, Carlos; Hernandez, Teresa; Costa, Francisco

1991-05-01

Seven mixtures from four organic residues—an aerobic sewage sludge, a city refuse, a peat residue, and a grape debris—were composted, and the changes undergone by their different carbon fractions during their composting and maturation were studied. In most cases a decrease in carbon fractions during the composting and maturation processes was observed. The extractable carbon, however, increased during maturation. Organic matter mineralization was greater in the composts with city refuse than in those with sewage sludge. The samples with peat residue showed the lowest decreases in carbon fractions. During maturation, an increase of humiclike fraction was observed, which was reflected by a decrease in the soluble carbon-precipitated carbon ratio at pH 2. Water-soluble carbon was the carbon fraction most easily degradable by microorganisms, and its amount correlated significantly with composting time in all the samples.

The geology of selected peat-forming environments in temperate and tropical latitudes

USGS Publications Warehouse

Cameron, C.C.; Palmer, C.A.; Esterle, J.S.

1990-01-01

We studied peat in several geologic and climatic settings: (1) a glaciated terrain in cold-temperate Maine and Minnesota, U.S.A.; (2) an island in a temperate maritime climate in the Atlantic Ocean off the coast of Maine, U.S.A., where sea level is rising rapidly and changing the environment of peat accumulation; (3) swamps along the warm-temperate U.S. Atlantic and Gulf Coastal Plains, where sea level has changed often, thus creating sites for accumulation; and (4) in a tropical climate along the coast of Sarawak, Malaysia, and the delta of the Batang Hari River, Sumatra, Indonesia (Figs. 1 and 2). With the exception of the deposits on the Atlantic and Gulf Coastal Plains, most of the deposits described are domed bogs in which peat accumulation continued above the surface of the surrounding soil. The bogs of the U.S. Atlantic and Gulf Coastal Plains have almost level surfaces. All domed bogs are not entirely ombrotrophic (watered only from precipitation); multidomed bogs that rise from irregular or hilly surfaces may be crossed by streams that supply water to the bogs. The geologic processes or organic sedimentation, namely terrestrialization and paludification, are similar in all peat deposits considered here. Differences in geomorphology affecting the quantity and that quality of peat that has ash contents of less than 25%, which are desirable for commercial purposes, depend chiefly on: (1) high humidity, which is favorable to luxuriant growth of peat-forming vegetation; (2) a depositional setting that permits extensive accumulation relatively free from inorganic contamination from sea water and streams and from dust and volcanic ash; and (3) a stable regional water table that controls the rate of decomposition under aerobic conditions and protects the deposit against the ravages of fire. Differences in peat textures are due to the type of vegetation and to the degree of decomposition. The rate of decomposition is largely the result of the amount of oxidation and aerobic microbial activity. Stratigraphic distribution of various textures and amounts of inorganic components within a peat deposit is largely determined by the vertical positions occupied by peat-forming environments, such as pond, marsh, swamp and heath where vegetation accumulated, and the depth to zones of unoxygenated water. Peat also differs in the rate of accumulation. On the basis of carbon-14 dating, an estimated 8 m of peat in the tropical Batang Hari River deposit in Sumatra has been accumulating at the rate of about 1.5 m/1,000 yr, whereas peat in the cold-temperate deposit in Maine has been accumulating at the rate of 0.66 m/1,000 yr. Accumulation rates in domed deposits such as these are affected not only by factors controlling volume of biomass and aerobic decay but also by stream erosion and fires that remove peat. Such disconformities (see Fig. 2) within the deposit may be recognized by sudden vertical changes in degree of decomposition and/or the presence of charcoal. The trace-element content of peat deposits is affected by the environments of their settings. Samples of peat that have an ash content of less than 25% dry weight and that are from small, almost level swamp deposits along the Atlantic Coastal Plain of North Carolina were compared with similar samples from small domed bogs in Maine, a glaciated area. Samples from Nort Carolina, which are from deposits in thick fluvial and nearshore marine sediments far from the bedrock source, are generally higher in Ti, Cr and Pb. The Maine samples from deposits in glacial drift close to the bedrock source contain more Zn, Mn, P, Ca, Na and Fe. The kind and amount of trace elements within the deposits appear to relate largely to depositional setting, to kinds of bedrock source, and to the modes of transportation from source to peat swamp. Trace-element concentrations in the extensive Sumatra peat deposit, which represents a potentially commercial coal bed, are similar to those found in Appalachian c

Contrasting vulnerability of drained tropical and high-latitude peatlands to fluvial loss of stored carbon

NASA Astrophysics Data System (ADS)

Evans, Chris D.; Page, Susan E.; Jones, Tim; Moore, Sam; Gauci, Vincent; Laiho, Raija; Hruška, Jakub; Allott, Tim E. H.; Billett, Michael F.; Tipping, Ed; Freeman, Chris; Garnett, Mark H.

2014-11-01

Carbon sequestration and storage in peatlands rely on consistently high water tables. Anthropogenic pressures including drainage, burning, land conversion for agriculture, timber, and biofuel production, cause loss of pressures including drainage, burning, land conversion for agriculture, timber, and biofuel production, cause loss of peat-forming vegetation and exposure of previously anaerobic peat to aerobic decomposition. This can shift peatlands from net CO2 sinks to large CO2 sources, releasing carbon held for millennia. Peatlands also export significant quantities of carbon via fluvial pathways, mainly as dissolved organic carbon (DOC). We analyzed radiocarbon (14C) levels of DOC in drainage water from multiple peatlands in Europe and Southeast Asia, to infer differences in the age of carbon lost from intact and drained systems. In most cases, drainage led to increased release of older carbon from the peat profile but with marked differences related to peat type. Very low DOC-14C levels in runoff from drained tropical peatlands indicate loss of very old (centuries to millennia) stored peat carbon. High-latitude peatlands appear more resilient to drainage; 14C measurements from UK blanket bogs suggest that exported DOC remains young (<50 years) despite drainage. Boreal and temperate fens and raised bogs in Finland and the Czech Republic showed intermediate sensitivity. We attribute observed differences to physical and climatic differences between peatlands, in particular, hydraulic conductivity and temperature, as well as the extent of disturbance associated with drainage, notably land use changes in the tropics. Data from the UK Peak District, an area where air pollution and intensive land management have triggered Sphagnum loss and peat erosion, suggest that additional anthropogenic pressures may trigger fluvial loss of much older (>500 year) carbon in high-latitude systems. Rewetting at least partially offsets drainage effects on DOC age.

Peat δ13Ccelluose-recorded wetting trend during the past 8000 years in the southern Altai Mountains, northern Xinjiang, NW China

NASA Astrophysics Data System (ADS)

Zhang, Dongliang; Feng, Zhaodong; Yang, Yunpeng; Lan, Bo; Ran, Min; Mu, Guijin

2018-05-01

There have been large discrepancies in the proposed mechanisms accounting for the wetting trend since ∼8.0 cal. kyr BP in the Altai Mountains and the surrounding areas. To validate or invalidate the widely reported wetting trend, we obtained a carbon isotope of cellulose (δ13Ccelluose)-recorded warm-season moisture history from a Narenxia (NRX) peat core in the southern Altai Mountains, northern Xinjiang, NW China. The δ13Ccelluose-recorded warm-season moisture reconstruction of the NRX peat core provides a strong support to the widely-reported proposition that the climate was generally dry before ∼8.0 cal. kyr BP and was changed to a wetting trend during the past ∼8000 years in the Altai Mountains and the surrounding areas. The wetting trend since ∼8.0 cal. kyr BP well resembles the increasing trend of the reconnaissance drought index (RDI) that was calculated on the basis of pollen-inferred temperature and precipitation data from the same core. The resemblance implies that the wetting trend during the past ∼8000 years resulted from the combined effect of temperature and precipitation.

Hydrogeology of the Seldovia area, Alaska

USGS Publications Warehouse

Nelson, Gordon L.; Danskin, Wesley R.

1980-01-01

Surficial materials in the Seldovia area, Alaska, are mapped as glacial drift over sedimentary bedrock, glacial drift over igneous and metamorphic bedrock, valley-bottom, alluvium, alluvial fan deposits, beach and intertidal deposits, and peat. Unconsolidated materials are generally less than 10 feet thick except in well-drained glacial deposits along the Seldovia-Jakolof Bay Road and in depressions in the bedrock surface. These depressions are poorly drained and commonly contain peat bogs. Development of domestic wells (1-15 gallons per minute) may be possible from unconsolidated materials and sedimentary bedrock, but larger water requirements must be met from surface-water sources. In areas having the water table or top of bedrock at shallow depths, effluent from sewage disposal systems may cause pollution of the land surface and nearby surface water. Seepage from hillside aquifers and unstable land along the coast of Kachemak Bay may adversely affect roads and structures. (USGS)

Water uptake by fresh Indonesian peat burning particles is limited by water-soluble organic matter

NASA Astrophysics Data System (ADS)

Chen, Jing; Hapsari Budisulistiorini, Sri; Itoh, Masayuki; Lee, Wen-Chien; Miyakawa, Takuma; Komazaki, Yuichi; Qing Yang, Liu Dong; Kuwata, Mikinori

2017-09-01

The relationship between hygroscopic properties and chemical characteristics of Indonesian biomass burning (BB) particles, which are dominantly generated from peatland fires, was investigated using a humidified tandem differential mobility analyzer. In addition to peat, acacia (a popular species at plantation) and fern (a pioneering species after disturbance by fire) were used for experiments. Fresh Indonesian peat burning particles are almost non-hygroscopic (mean hygroscopicity parameter, κ < 0.06) due to predominant contribution of water-insoluble organics. The range of κ spans from 0.02 to 0.04 (dry diameter = 100 nm, hereinafter) for Riau peat burning particles, while that for Central Kalimantan ranges from 0.05 to 0.06. Fern combustion particles are more hygroscopic (κ = 0. 08), whereas the acacia burning particles have a mediate κ value (0.04). These results suggest that κ is significantly dependent on biomass types. This variance in κ is partially determined by fractions of water-soluble organic carbon (WSOC), as demonstrated by a correlation analysis (R = 0.65). κ of water-soluble organic matter is also quantified, incorporating the 1-octanol-water partitioning method. κ values for the water extracts are high, especially for peat burning particles (A0 (a whole part of the water-soluble fraction): κ = 0.18, A1 (highly water-soluble fraction): κ = 0.30). This result stresses the importance of both the WSOC fraction and κ of the water-soluble fraction in determining the hygroscopicity of organic aerosol particles. Values of κ correlate positively (R = 0.89) with the fraction of m/z 44 ion signal quantified using a mass spectrometric technique, demonstrating the importance of highly oxygenated organic compounds to the water uptake by Indonesian BB particles. These results provide an experimentally validated reference for hygroscopicity of organics-dominated particles, thus contributing to more accurate estimation of environmental and climatic impacts driven by Indonesian BB particles on both regional and global scales.

The lignin component of humic substances: Distribution among soil and sedimentary humic, fulvic, and base-insoluble fractions

NASA Astrophysics Data System (ADS)

Ertel, John R.; Hedges, John I.

1984-10-01

Vanillyl, syringyl and cinnamyl phenols occur as CuO oxidation products of humic, fulvic and base-insoluble residual fractions from soils, peat and nearshore marine sediments. However, none of these lignin-derived phenols were released by CuO oxidation of deepsea sediment or its base-extractable organic fractions. Lignin analysis indicated that peat and coastal marine sediments contained significantly higher levels of recognizable vascular plant carbon (20-50%) than soils and offshore marine sediments (0-10%). Although accounting for less than 20% of the total sedimentary (bulk) lignin, lignin components of humic acid fractions compositionally and quantitatively resembled the corresponding bulk samples and baseinsoluble residues. Recognizable lignin, presumably present as intact phenylpropanoid units, accounted for up to 5% of the carbon in peat and coastal humic acids but less than 1% in soil humic acids. Fulvic acid fractions uniformly yielded less lignin-derived phenols in mixtures that were depleted in syringyl and cinnamyl phenols relative to the corresponding humic acid fractions. Within the vanillyl and syringyl families the relative distribution of acidic and aldehydic phenols is a sensitive measure of the degree of oxidative alteration of the lignin component The high acid/aldehyde ratios and the low phenol yields of soils and their humic fractions compared to peat and coastal sediments indicate extensive degradation of the lignin source material. Likewise, the progressively higher acid/aldehyde ratios and lower phenol yields along the sequence: plant tissues (plant debris)-humic acids-fulvic acids suggest that this pattern represents the diagenetic sequence for the aerobic degradation of lignin biopolymers.

Chemical characteristics of dissolved organic matter (DOM) in relation to heavy metal concentrations in soil water from boreal peatlands after clear-cut harvesting

NASA Astrophysics Data System (ADS)

Kiikkilä, O.; Nieminen, T.; Starr, M.; Ukonmaanaho, L.

2012-04-01

Boreal peatlands form an important terrestrial carbon reserve and are a major source of dissolved organic matter (DOM) to surface waters, particularly when disturbed through forestry practices such as draining or timber harvesting. Heavy metals show a strong affinity to organic matter and so, along with DOM, heavy metals can be mobilized and transported from the soil to surface waters and sediments where they may become toxic to aquatic organisms and pass up the food chain. The complexation of heavy metals with DOM can be expected to be related and determined by the chemical characteristics of DOM and oxidation/reducing conditions in the peat. We extracted interstitial water from peat samples and determined the concentrations of dissolved organic carbon (DOC), dissolved organic nitrogen (DON) and Al, Cu, Zn and Fe in various fractions of DOM isolated by adsorption properties (XAD-8 fractionation) and molecular-weight (ultrafiltration). The peat samples were taken from 0-30 and 30-50 cm depth in drained peatland catchments two years after whole-tree or stem-only clear-cut harvesting (Scots pine or Norway spruce) had been carried out. The samples from the upper layer had been subject to alternating saturation/aeration conditions while the deeper layer had been continuously under the water table. The fractionation of DOC and DON according to both adsorption properties and molecular-weight fractions clearly differed between the upper and lower peat layers. While the hydrophobic acid fraction contained proportionally more DOC and DON than the hydrophilic acid fraction in the upper peat layer the results were vice versa in the lower peat layer. High-molecular-weight compounds (> 100 kDa) were proportionally more abundant in the upper and low-molecular-weight compounds (< 1 kDa) in the lower peat layer. These differences are assumed to reflect differences in the aerobic/ anaerobic conditions and degree of decomposition between the two layers. The concentrations of Zn, Al, Fe and DON correlated positively with DOC concentrations whereas the concentration Cu did not correlate with DOC concentrations. Heavy metal concentrations in different molecular-weight fractions indicated that Al, Cu, Zn and Fe were mostly associated with high-molecular-weight compounds and only a small fraction existed as free metal ions in solution. There were no clear differences in the chemical characteristics of DOC or DON or heavy metal concentrations between the two harvesting treatments.

Peatland Ecosystem Processes in the Maritime Antarctic During Warm Climates.

PubMed

Loisel, Julie; Yu, Zicheng; Beilman, David W; Kaiser, Karl; Parnikoza, Ivan

2017-09-27

We discovered a 50-cm-thick peat deposit near Cape Rasmussen (65.2°S), in the maritime Antarctic. To our knowledge, while aerobic 'moss banks' have often been examined, waterlogged 'peatlands' have never been described in this region before. The waterlogged system is approximately 100 m 2 , with a shallow water table. Surface vegetation is dominated by Warnstorfia fontinaliopsis, a wet-adapted moss commonly found in the Antarctic Peninsula. Peat inception was dated at 2750 cal. BP and was followed by relatively rapid peat accumulation (~0.1 cm/year) until 2150 cal. BP. Our multi-proxy analysis then shows a 2000-year-long stratigraphic hiatus as well as the recent resurgence of peat accumulation, sometime after 1950 AD. The existence of a thriving peatland at 2700-2150 cal. BP implies regionally warm summer conditions extending beyond the mid-Holocene; this finding is corroborated by many regional records showing moss bank initiation and decreased sea ice extent during this time period. Recent peatland recovery at the study site (<50 years ago) might have been triggered by ongoing rapid warming, as the area is experiencing climatic conditions approaching those found on milder, peatland-rich sub-Antarctic islands (50-60°S). Assuming that colonization opportunities and stabilization mechanisms would allow peat to persist in Antarctica, our results suggest that longer and warmer growing seasons in the maritime Antarctic region may promote a more peatland-rich landscape in the future.

Seasonal variation in CH4 emissions and production and oxidation potentials at microsites on an oligotrophic pine fen.

PubMed

Saarnio, S; Alm, Jukka; Silvola, Jouko; Lohila, Annalea; Nykänen, Hannu; Martikainen, Pertti J

1997-04-01

 Temporal and spatial variation in CH 4 emissions was studied at hummock, Eriophorum lawn, flark and Carex lawn microsites in an oligotrophic pine fen over the growing season using a static chamber method, and CH 4 production and oxidation potentials in peat profiles from hummock and flark were determined in laboratory incubation experiments. Emissions were lowest in the hummocks, and decreased with increasing hummock height, while in the lawns and flarks they increased with increasing sedge cover. Statistical response functions with water table and peat temperature as independent variables were calculated in order to reconstruct seasonal CH 4 emissions by reference to the time series for peat temperature and water table specific to each microsite type. Mean CH 4 emissions in the whole area in the snow-free period of 1993, weighted in terms of the proportions of the microsites, were 1.7 mol CH 4 m -2 . Potential CH 4 production and oxidation rates were very low in the hummocks rising above the groundwater table, but were relatively similar when expressed per dry weight of peat both in the hummocks and flarks below the water table. The CH 4 production potential increased in autumn at both microsites and CH 4 oxidation potential seemed to decrease. The decrease in temperature in autumn certainly reduced in situ decomposition processes, possibly leaving unused substrates in the peat, which would explain the increase in CH 4 production potential.

Sundaland Peat Carbon Dynamics and Its Contribution to the Holocene Atmospheric CO2 Concentration

NASA Astrophysics Data System (ADS)

Abrams, Jesse F.; Hohn, Sönke; Rixen, Tim; Merico, Agostino

2018-04-01

The Sunda Shelf is a large submerged extension of the continental shelf of mainland Asia, joining the islands of Borneo, Java, and Sumatra and forming the shallow seabed of the South China Sea. Recent studies identified present-day peatlands in Southeast Asia as a globally important carbon reservoir. However, little is known about Sundaland paleopeatlands and their role in the global carbon cycle since the Last Glacial Maximum. Using a topography-based, sea level-driven model, we estimate the potential spatial extent of peatlands during the late Pleistocene and early Holocene across the low-lying Sundaland plains. We then use the estimated peatland area together with data on carbon accumulation rates to calculate the total peat carbon pool on the Sunda Shelf. Finally, using a global biogeochemical model, we analyze the relative influence of the predicted Sundaland peat dynamics and other carbon change mechanisms, specifically high-latitude forest growth and peat formation, shallow sea carbonate deposition, ocean warming, and combinations of them, on the global carbon cycle of the Holocene. We identify a feedback mechanism between sea level and peatland carbon sequestration in Sundaland that reduced atmospheric CO2 concentration by about 4-5 ppm and increased δ13C by 0.05‰ during the Holocene. We also show that a concurrence of mechanisms that includes Sundaland peat dynamics produces model results that are consistent with proxy records, especially with respect to δ13C.

Lateral expansion and carbon exchange of a boreal peatland in Finland resulting in 7000 years of positive radiative forcing

NASA Astrophysics Data System (ADS)

Mathijssen, Paul J. H.; Kähkölä, Noora; Tuovinen, Juha-Pekka; Lohila, Annalea; Minkkinen, Kari; Laurila, Tuomas; Väliranta, Minna

2017-03-01

Data on past peatland growth patterns, vegetation development, and carbon (C) dynamics during the various Holocene climate phases may help us to understand possible future climate-peatland feedback mechanisms. In this study, we analyzed and radiocarbon dated several peat cores from Kalevansuo, a drained bog in southern Finland. We investigated peatland succession and C dynamics throughout the Holocene. These data were used to reconstruct the long-term atmospheric radiative forcing, i.e., climate impact of the peatland since initiation. Kalevansuo peat records revealed a general development from fen to bog, typical for the southern boreal zone, but the timing of ombrotrophication varied in different parts of the peatland. Peat accumulation patterns and lateral expansion through paludification were influenced by fires and climate conditions. Long-term C accumulation rates were overall lower than the average values found from literature. We suggest the low accumulation rates are due to repeated burning of the peat surface. Drainage for forestry resulted in a nearly complete replacement of typical bog mosses by forest species within 40 years after drainage. The radiative forcing reconstruction suggested positive values (warming) for the first 7000 years following initiation. The change from positive to negative forcing was triggered by an expansion of bog vegetation cover and later by drainage. The strong relationship between peatland area and peat type with radiative forcing suggests a possible feedback for future changing climate, as high-latitude peatlands may experience prominent regime shifts, such as fen to bog transitions.

Partitioning Carbon Dioxide Emission and Assessing Dissolved Organic Carbon Leaching of a Drained Peatland Cultivated with Pineapple at Saratok, Malaysia

PubMed Central

Lim Kim Choo, Liza Nuriati; Ahmed, Osumanu Haruna

2014-01-01

Pineapples (Ananas comosus (L.) Merr.) cultivation on drained peats could affect the release of carbon dioxide (CO2) into the atmosphere and also the leaching of dissolved organic carbon (DOC). Carbon dioxide emission needs to be partitioned before deciding on whether cultivated peat is net sink or net source of carbon. Partitioning of CO2 emission into root respiration, microbial respiration, and oxidative peat decomposition was achieved using a lysimeter experiment with three treatments: peat soil cultivated with pineapple, bare peat soil, and bare peat soil fumigated with chloroform. Drainage water leached from cultivated peat and bare peat soil was also analyzed for DOC. On a yearly basis, CO2 emissions were higher under bare peat (218.8 t CO2 ha/yr) than under bare peat treated with chloroform (205 t CO2 ha/yr), and they were the lowest (179.6 t CO2 ha/yr) under cultivated peat. Decreasing CO2 emissions under pineapple were attributed to the positive effects of photosynthesis and soil autotrophic activities. An average 235.7 mg/L loss of DOC under bare peat suggests rapid decline of peat organic carbon through heterotrophic respiration and peat decomposition. Soil CO2 emission depended on moderate temperature fluctuations, but it was not affected by soil moisture. PMID:25215335

Influence of different kind of peats on some physic-chemical properties, biochemical activity, the content of different forms of nitrogen and fractions of humic substances of The Great Vasyugan Mire

NASA Astrophysics Data System (ADS)

Inisheva, L. I.; Szajdak, L.

2009-04-01

Mires, or peatlands belong to the wetlands ecosystems where carbon is bounded in primary production and deposited as peat in water saturated, anoxic conditions. In those conditions, the rate of the supply of new organic matter has exceeded that the decomposition, resulting in carbon accumulation. Place of sampling belongs to an oligotrophic landscapes of the river Klyuch basin in spurs of Vasyugan mire. The catchment represents reference system for Bokchar swampy area (political district of Tomsk region). Landscape profile crosses main kinds of swampy biogeocoenosis (BGC) toward the mire center: paludal tall mixed forest, pine undershrub Sphagnum (high riam, trans-accumulative part of a profile, P2), pine-undershrub Sphagnum (low riam, transit part, P3), sedge-moss swamp (eluvial part, P5). The latter represents an eluvial part of a slope of watershed massif where it is accomplished discharge of excess, surface, soil-mire waters. The depth of peat deposit of sedge-moss swamp reaches 2,5m. To the depth of 0,6m there is a layer of Sphagnum raised bog peat, then it is a mesotrophic Scheuchzeria Sphagnum layer and at the bottom there is a thick layer of low-mire horsetail peat. The samples of peats were taken from two places (P2 and P3), both from the depth 0-75 cm of the great Vasyugan Mire. These materials represent (P2) Sphagnum fuscum peat (ash content ranged from 10.8 to 15.1%), but samples P3 belong to low-moor sedge peat (ash content ranged from 4.5-4.8%). The differences in water level, redox potential, pH, degree of degradation, bulk density, number of microorganisms, activity of enzymes, different kinds of nitrogen and humic substances were studied in two different peat soils characterized by different type of peat. In general in P2 the redox potential changed from 858 to /-140/ mV, higher activity of xanthine oxidase and peroxidase, different kinds of microorganisms (ammonifing bacteria and cellulose decomposing microorganisms) and different kinds of nitrogen (mineral, easily hydrolysable, hardly hydrolysable and non-hydrolyzable), bitumines, 3 fractions of humic acids and 3 fractions of fulvic acids were determined in the deep 0-25 cm than in 50-75 cm. The ratio HA/FA in the depth 0-25 cm was equal to from 1.87, but in the depth 50-75 cm was equal to 7.66. Contrary was observed for P3. For this peat with the increase of the deep of sampling the decrease of total nitrogen, activity of enzymes (xanthine oxidase and peroxidase) is connected with the changes of Fe+2/Fe+3 and lower difference of redox potential than in P2. The ratio HA/FA in the depth 0-25 cm was equal to 0.56, but in the depth 50-70 cm was equal to 0.84.

Evaluation of Reactive Mixtures for Treatment of Mine Drainage From a Waste Rock Storage Area in Northern Saskatchewan, Canada

NASA Astrophysics Data System (ADS)

Jeen, S.; Bain, J. G.; Blowes, D. W.

2007-12-01

A column experiment has been conducted to evaluate the performance of three reactive mixtures which may be used in a permeable reactive barrier (PRB) for the treatment of low quality mine drainage water from a waste rock storage area in northern Saskatchewan, Canada. The key element of concern in the drainage water is dissolved Ni, which occurs at approximately 13 mg/L. The water is low pH ~4.3, oxidized, contains high concentrations of dissolved sulfate (4400-4750 mg/L), Al (45 mg/L), Zn (3 mg/L), Co (3 mg/L) and relatively low concentrations of other dissolved heavy metals and iron. Three columns, each containing one of the mixtures, were constructed: column A (peat/lime/limestone/gravel), column B (peat/zero valent iron (ZVI) filings (20%/vol)/limestone/gravel), and column C (peat/ZVI filings (10%/vol)/limestone/gravel). The experimental results have shown that the mixtures promote bacterially-mediated sulfate reduction and metal removal by precipitation of metal sulfides, metal precipitation, and adsorption under relatively high pH conditions (pH of 7 to 8). Reducing conditions (Eh of 0 to -200 mV) have developed in all of the columns, from the highly oxidized influent water (Eh of +500 to +600 mV). Hydrogen sulfide is detected in the effluent water, and dissolved sulfate concentrations decrease by several hundred mg/L. Based on sulfate removal, sulfate reduction occurs more strongly in columns B and C than column A. All of the columns are removing Ni to below the limit of detection (typically < 0.01 mg/L); however, the removal rate in column A is slower than in columns B and C and has decreased over time. Most other metals are removed to low concentrations in all of the columns. The results suggest that while the longevity of mixtures including ZVI will be much longer than mixtures containing only peat, considering economic aspects, the PRB consisting of only peat could also be an alternative option, if breakthrough time can be predicted and replacement of peat can be conducted in a timely manner. This study shows that the use of reactive mixtures that facilitate microbial activities and redox reactions in subsurface could be a valuable means to remove various metal contaminants originated from mine drainage sites.

What controls the oxidative ratio of UK peats? A multi-site study of elemental CHNO concentrations in peat cores

NASA Astrophysics Data System (ADS)

Clay, Gareth; Worrall, Fred; Masiello, Carrie

2013-04-01

The oxidative ratio (OR) is the amount of CO2 sequestered in the terrestrial biosphere for each mol of O2 produced. The OR governs the effectiveness of a terrestrial biome to mitigate the impact of anthropogenic CO2 emissions and it has been used to calculate the balance of terrestrial and oceanic carbon sinks across the globe. However, few studies have investigated the controls of the variability in OR. What factors affect OR - climate? Soil type? Vegetation type? N deposition? Land use? Land use change? Small shifts in OR could have important implications in the global partitioning of CO2 between the atmosphere, biosphere, and oceans. This study looks at peat soils from a series of sites representing a climatic transect across the UK. Duplicate peat cores were taken, along with samples of above-ground vegetation and litter, from sites in northern Scotland (Forsinard), southern Scotland (Auchencorth), northern England (Moor House; Thorne Moor) through the Welsh borders (Whixhall Moss) and Somerset levels (Westhay Moor) to Dartmoor and Bodmin Moor in the south west of England. Sub-samples of the cores were analysed for their CHNO concentrations using a Costech ECS 4010 Elemental combustion system. Using the method of Masiello et al. (2008), OR values could be calculated from these elemental concentrations. Results show that OR values of UK peats varied between 0.82 and 1.27 with a median value of 1.08 which is within the range of world soils. There were significant differences in OR of the peat between sites with the data falling into two broad groupings - Group 1: Forsinard, Auchencorth, Dartmoor and Bodmin Moor; Group 2: Moor House, Thorne Moor, Westhay Moor, Whixhall Moss. Whilst there were significant changes (p < 0.05) in elemental ratios with increasing peat depth (increasing C:N ratio and decreasing O:C ratio) there was no significant difference overall in OR with depth. This paper will explore some of the possible controlling factors on these ratios. Local vegetation was also sampled along with agricultural soils from the local area of the peat cores to compare the relative differences in different mediums. Significant differences (p < 0.01) between vegetation, agricultural soils and surface peat layers were found where vegetation had OR values of 1.03 ± 0.04 and agricultural soils had OR values of 1.15 ± 0.04. Further discussion of these results from these comparisons is also presented in this study.

Investigating the potential of floating mires as record of palaeoenvironmental changes

NASA Astrophysics Data System (ADS)

Zaccone, C.; Adamo, P.; Giordano, S.; Miano, T. M.

2012-04-01

Peat-forming floating mires could provide an exceptional resource for palaeoenvironmental and environmental monitoring studies, as much of their own history, as well as the history of their surrounds, is recorded in their peat deposits. In his Naturalis historia (AD 77-79), Pliny the Elder described floating islands on Lake Vadimonis (now Posta Fibreno Lake, Italy). Actually, a small floating island (ca. 35 m of diameter and 3 m of submerged thickness) still occurs on this calcareous lake fed by karstic springs at the base of the Apennine Mountains. Here the southernmost Italian populations of Sphagnum palustre occur on the small surface of this floating mire known as "La Rota", i.e., a cup-formed core of Sphagnum peat and rhizomes of Helophytes, erratically floating on the water-body of a submerged doline, annexed to the easternmost edge of the lake, characterised by the extension of a large reed bed. Geological evidence point out the existence in the area of a large lacustrine basin since Late Pleistocene. The progressive filling of the lake caused by changing in climatic conditions and neotectonic events, brought about the formation of peat deposits in the area, following different depositional cycles in a swampy environment. Then, a round-shaped portion of fen, originated around lake margins in waterlogged areas, was somehow isolated from the bank and started to float. Coupling data about concentrations and fluxes of several major and trace elements of different origin (i.e., dust particles, volcanic emissions, cosmogenic dusts and marine aerosols), with climate records (plant micro- and macrofossils, pollens, isotopic ratios), biomolecular records (e.g., lipids), detailed age-depth modelling (i.e., 210Pb, 137Cs, 14C), and humification indexes, the present work is hoped to identify and better understand the reliability of this particular "archive", and thus possible relationships between biogeochemical processes occurring in this floating bog and environmental changes.

Applications of peat-based sorbents for removal of metals from water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cohen, A.D.; Stack, E.M.; Eltayeb, S.

1995-12-31

The results reported in this paper are derived from one part of an ongoing investigation of peat sorption properties, in particular, the capacities of acid-treated peats to adsorb chromium, nickel, zinc, copper, and cadmium from water. Acid treatment was done to remove as much previously adsorbed metal as possible before testing. Four peat types were selected for study, two highly decomposed types (a woody, Taxodium-dominated peat from the Okefenokee Swamp of Georgia and a sedge-dominated, charcoal-rich peat from the Tamiami Trail region of Florida) and two less decomposed ones (a Sphagnum moss-dominated peat from Maine and a Nymphaea-dominated peat frommore » the Okefenokee Swamp of Georgia). Single metal and mixed metal solutions were tested in slurry experiments with each peat type. Solutions were analyzed using a Perkin-Elmer model 305B Flame Atomic Absorption Spectrophotometer. In single metal tests, chromium and copper tended to be adsorbed to a greater extent than the other metals. Three of the peats were found to be capable of adsorbine more copper ions than zince ions, while a fourth type adsorbed approximately the same amounts of each. Degree of decomposition of the peats tended to affect sorption properties for certain metals. The results of batch studies revealed that chromium was always preferentially adsorbed regardless of the peat type tested. The results of these studies further confirm that remediation of metal-contaminated waters using peats will require selection of specific peats to match the contaminants.« less

Peat deposits of North Carolina: Bulletin 88

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ingram, R.L.

1987-01-01

Fuel-grade peat is an accumulation of partially decomposed plant material that has less than 25% non-combustible material (ash). In eastern North Carolina peat has formed in the past 10,000 years in swamps or pocosins (coastal swamps), Carolina bays, and river floodplains. Most of the peat is found at the surface with no over-burden and usually ranges in thickness from 1 to 15 ft with an average of 4-1/2 ft. The mean ash content of the fuel-grade peats is about 7.4%, but ash contents of less than 5% are common in most peat deposits. Heating values average 10,100 Btu/lb on amore » moisture-free basis. Fuel-grade peat deposits cover about 677,000 acres (1060 sq mi) in coastal North Carolina with total resources of about 500 million tons of moisture-free peat. Of this total, about 284,000 acres (444 sq mi) with 319 million tons are underlain by peat greater than 4 ft thick. Peat resources are concentrated in the pocosins or coastal swamps of northeastern North Carolina with the Albemarle-Pamlico peninsula having 55% of the resources and the Dismal Swamp, 11%. The remaining coastal swamp deposits are small but significant. Although 96 Carolina bays have peat, only 46 have peat greater than 4 ft thick; and only one has more than 1 million tons of peat. None of the river floodplain peats located were very large, continuous, or of high quality. 75 refs.« less

Terrain Analysis Procedural Guide for Soil. Report Number 6 in the ETL Series on Guides for Army Terrain Analysts

DTIC Science & Technology

1981-02-01

01 T3 Swamp Pt. OH. CH. MH. OL T4 Peat Bog Pt T5 . - Peat Cuttings Pt T6 Cranberry Bog Pt. OH. CH. MH, OL T7 Rice holds Pt. OH, CH, MH, OL ’ ~Known...Commonly Associated Soils Landlorm/erc Climate Horizon USCS Symbol Coastal Plain unspecified unspecified OL. ML. CL. ML-CL, MH. Depressions CH, OH...total sample. SALINA A salt marsh or pond located adjacent to the sea, but not open to the sea. SALT PAN Any flat area or natural depression where water

Changes of the green house gas production potential of inundated peatlands in the perspective of temporal vegetation shifts

NASA Astrophysics Data System (ADS)

Zak, Dominik; Reuter, Hendrik; Augustin, Jürgen; Shatwell, Tom; Barth, Martin; Gelbrecht, Jörg; McInnes, Rob

2015-04-01

Artificially drained minerotrophic peatlands, commonly called fens, are being rewetted on a large scale in many European countries, including Germany. The objectives behind rewetting include the reduction of greenhouse gas (GHG) emissions, in particular of carbon dioxide (CO2) via oxidative degradation processes in the aerated peat soil, as well as the recovering of the nutrient sink and ecological habitat functions of pristine fens. As a result of long-term organic soil losses, subsidence and the associated lowering of the land surface, rewetting of these areas often results in shallow lake formation. These developing ecosystems differ considerably from pristine fens. Peat formation cannot occur in the open waterbody; instead the highly degraded submerged peat surface becomes covered by organic sediments which form readily due to the subaqueous decomposition of dying grassland vegetation that is intolerant to permanent flooding and the decomposition of shoot biomass from wetland plants. With regard to lake ontogeny, these sites can be compared to lakes in the process of terrestrialization, where peat formation can follow as infill proceeds to surface levels. These newly formed shallow lakes with a highly degraded peat substrate are characteristically eutrophic and show high mobilisations of nutrients and dissolved organic carbon. Furthermore, extremely high methane (CH4) emissions from rewetted fens have been observed. The GHG emissions in the initial stage after rewetting have even been shown to lead to a net climate impact that exceeds that of drained fens. Another distinct difference of rewetted fens from natural fens in Central Europe is the rapid secondary plant succession. In the initial phase of rewetting, Phalaris arundinacea has been observed to be the dominating plant species; more adapted to wet-dry conditions, this species routinely dies off within the first year of inundation. Helophytes like Typha latifolia in marginal areas and Ceratophyllum demersum in the open waterbody have been observed to colonize the area within one or two years of rewetting. With increasing rewetting time, the peat forming plants Phragmites australis and various Carex species, such as Carex riparia, can become re-established. The influence of these predictable vegetation shifts on CO2 and CH4 emissions has not been studied yet. In this paper, the CO2 and CH4 production due to the subaqueous decomposition of these five most abundant plant species, which are considered to be representative of different rewetting stages, will be presented. Beside continuous gas flux measurements, bulk chemical analysis of plant tissue, including C, N, P, and plant polymer dynamics, were performed in order to gain further insights into changing litter characteristics. With respect to temporal vegetation shifts in rewetted fens, the results provide new insights into the mid-term climate effect of these ecosystems.

Investigating the impact of land cover change on peak river flow in UK upland peat catchments, based on modelled scenarios

NASA Astrophysics Data System (ADS)

Gao, Jihui; Holden, Joseph; Kirkby, Mike

2014-05-01

Changes to land cover can influence the velocity of overland flow. In headwater peatlands, saturation means that overland flow is a dominant source of runoff, particularly during heavy rainfall events. Human modifications in headwater peatlands may include removal of vegetation (e.g. by erosion processes, fire, pollution, overgrazing) or pro-active revegetation of peat with sedges such as Eriophorum or mosses such as Sphagnum. How these modifications affect the river flow, and in particular the flood peak, in headwater peatlands is a key problem for land management. In particular, the impact of the spatial distribution of land cover change (e.g. different locations and sizes of land cover change area) on river flow is not clear. In this presentation a new fully distributed version of TOPMODEL, which represents the effects of distributed land cover change on river discharge, was employed to investigate land cover change impacts in three UK upland peat catchments (Trout Beck in the North Pennines, the Wye in mid-Wales and the East Dart in southwest England). Land cover scenarios with three typical land covers (i.e. Eriophorum, Sphagnum and bare peat) having different surface roughness in upland peatlands were designed for these catchments to investigate land cover impacts on river flow through simulation runs of the distributed model. As a result of hypothesis testing three land cover principles emerged from the work as follows: Principle (1): Well vegetated buffer strips are important for reducing flow peaks. A wider bare peat strip nearer to the river channel gives a higher flow peak and reduces the delay to peak; conversely, a wider buffer strip with higher density vegetation (e.g. Sphagnum) leads to a lower peak and postpones the peak. In both cases, a narrower buffer strip surrounding upstream and downstream channels has a greater effect than a thicker buffer strip just based around the downstream river network. Principle (2): When the area of change is equal, the size of land cover change patches has no effect on river flow for patch sizes up to 40000m2. Principle (3): Bare peat on gentle slopes gives a faster flow response and higher peak value at the catchment outlet, while high density vegetation or re-vegetation on a gentle slope area has larger positive impact on peak river flow delay when compared with the same practices on steeper slopes. These simple principles should be useful to planners who wish to determine resource efficiency and optimisation for peatland protection and restoration works in headwater systems. If practitioners require further detail on impacts of specific spatial changes to land cover in a catchment then this modelling approach can be applied to new catchments of concern.

Impacts of rewetting on hydrological functioning and dissolved organic carbon flux in a degraded peatland (La Guette, France)

NASA Astrophysics Data System (ADS)

Bernard-Jannin, Léonard; Binet, Stéphane; Gogo, Sébastien; Lemoing, Franck; Zocatelli, Renata; Jozja, Nevila; Défarge, Christian; Laggoun-Défarge, Fatima

2016-04-01

In Sphagnum-dominated peatlands, dissolved organic carbon (DOC) fluxes are mainly controlled by peat water saturation state corresponding to the equilibrium between recharge/drainage fluxes and to the peat storage capacity. Rewetting is a wide spread method that has been used for restoring the global hydrological behavior of degraded peatland ecosystems. Therefore, there is a need to assess the impact of rewetting on peatland hydrology but also on the modification of dynamics and DOC fluxes that significantly impact on carbon sink function of these ecosystems. To investigate this question, meteorology, hydrological data, DOC concentrations and dissolved organic matter (DOM) quality (aromaticity and fluorescence) were monthly monitored at the watershed scales and in two piezometer transects since 2010 in a hydrologically disturbed peatland, La Guette, which experienced a rewetting action on February 2014. One piezometer transect (called downstream plots) was supposedly influenced by the hydrological restoration while the other (called upstream plots) was considered as a control. Collected data allowed studying the impact of the restoration on hydrology and dynamics and DOC fluxes in the peatland. Preliminary results indicate that water table level became more stable after the rewetting in the area affected by the restoration. This seems to have an impact on DOC quantity and quality since concentrations became higher in the same area with also a higher aromaticity degree and a larger proportion of low-weight molecules compared to upstream area. This could indicate that in the downstream area, more anaerobic conditions inhibit microorganism activity responsible for the mineralization of peat organic matter.

Interdependence of peat and vegetation in a tropical peat swamp forest.

PubMed Central

Page, S E; Rieley, J O; Shotyk, W; Weiss, D

1999-01-01

The visual uniformity of tropical peat swamp forest masks the considerable variation in forest structure that has evolved in response to differences and changes in peat characteristics over many millennia. Details are presented of forest structure and tree composition of the principal peat swamp forest types in the upper catchment of Sungai Sebangau, Central Kalimantan, Indonesia, in relation to thickness and hydrology of the peat. Consideration is given to data on peat geochemistry and age of peat that provide evidence of the ombrotrophic nature of this vast peatland and its mode of formation. The future sustainability of this ecosystem is predicted from information available on climate change and human impact in this region. PMID:11605630

Peatlands in a eutrophic world - assessing the state of a poor fen-bog transition in southern Ontario, Canada, after long term nutrient input and altered hydrological conditions

NASA Astrophysics Data System (ADS)

Berger, Sina; Gebauer, Gerhard; Blodau, Christian; Knorr, Klaus-Holger

2017-04-01

Peatlands are of vital importance for global carbon (C) cycling as they sequester and store enormous amounts of C. Major threats to peatlands are excessive supply of nutrients from the atmosphere as well as from surface water and groundwater. Up to this date our knowledge of long-term consequences of such excessive nutrient supply is limited. We are unsure about how long peatlands can maintain their functioning under such circumstances. We conducted a detailed study in a once ombrotrophic bog ecosystem (Wylde Lake peatland, Ontario, Canada), which is since the 19th century embedded in a eutrophic environment with intensive agriculture. Moreover, since AD 1954 the peatland borders a water reservoir which is strongly enriched with nutrients. Our objective was to elucidate to which extent the infiltration of nutrient from the peatland periphery can be buffered and whether the inner parts can maintain typical characteristics of a pristine bog. To achieve this goal, along a transect of study sites, we Pb-210- and Cs-137-dated peat cores and determined elements of peat using x-ray fluorescence (XRF). To calculate N input, nitrogen enrichment factors in the vegetation and abundances of stable N isotopes in the peat were determined through isotope ratio mass spectrometry (IRMS). Furthermore, we re-investigated the vascular plant species composition 31 years after a previous investigation and lastly, we sporadically measured greenhouse gas fluxes with chamber techniques. In the central part of the peatland we found great N input rates of 4.28±0.75 and 4.35±0.30 g N m-2 y-1, but even greater rates were found in the peatland fringe area (5.90±0.10 g N m-2 y-1). Also, all elements essential for plant growth were abundant in increased concentrations along all peat cores, especially near the bordering reservoir, presumably due to supply by the reservoir water. A more graminoid dominated vegetation in the wetter areas (near the reservoir) and a rapid increase of tree cover in drier areas (further away from the reservoir), both over a healthy Sphagnum carpet, as well as altered fluxes of CO2, CH4 and N2O indicate a transformation of the once ombrotrophic bog into a poor fen. Very much to our surprise the peatland did not seem to decay after long-term excessive nutrient load, instead it tremendously accelerated peat accumulation which led to maximum growth rates of up to 500 g C m-2 y-1. Peatland functioning in terms of carbon storage appeared to be maintained. Our study, which combines a great variety of methods and which provides detailed insights into various processes along peat profiles and vegetation cover, therefore contradicts numerous previous studies in which it was stated that long-term excessive supply of nutrients to peatlands would cause dying of Sphagnum mosses and hence, a decay and increased peat loss of the affected site already after one decade.

Peat Soil Stabilization using Lime and Cement

NASA Astrophysics Data System (ADS)

Zambri, Nadhirah Mohd; Ghazaly, Zuhayr Md.

2018-03-01

This paper presents a study of the comparison between two additive Lime and Cement for treating peat soil in term of stabilization. Peat and organic soils are commonly known for their high compressibility, extremely soft, and low strength. The aim of this paper is to determine the drained shear strength of treated peat soil from Perlis for comparison purposes. Direct Shear Box Test was conducted to obtain the shear strength for all the disturbed peat soil samples. The quick lime and cement was mixed with peat soil in proportions of 10% and 20% of the dry weight peat soil. The experiment results showed that the addition of additives had improved the strength characteristics of peat soil by 14% increment in shear strength. In addition, the mixture of lime with peat soil yield higher result in shear strength compared to cement by 14.07% and 13.5% respectively. These findings indicate that the lime and cement is a good stabilizer for peat soil, which often experienced high amount of moisture content.

Understanding the Impact of Land Management on Carbon Losses from Peatlands

NASA Astrophysics Data System (ADS)

Savage, A.; Holden, J.; Wainwright, J.

2010-05-01

British peatlands have historically been managed in many different ways to provide an income for rural communities. Such practices involve heather burning on grouse shooting estates, sheep grazing, drainage to increase the area of land available for agriculture and afforestation. Carbon budget calculations for unmanaged peatlands have demonstrated that peatlands are carbon sinks. At present, little is known about how management affects carbon stocks, and whether one strategy might be favoured over another in the future, from a carbon stock preservation perspective. As the need to safeguard carbon stocks rises up the political agenda, questions are being asked about how peatlands should be managed to limit carbon losses. Carbon cycling in peat is governed by four drivers (Laiho, 2006), environmental conditions (e.g. temperature, water table level), substrate quality (e.g. how recalcitrant the peat is), nutrients (e.g. nitrogen required to synthesis the carbon stocks) and microbial community (e.g. are the microbes present able to utilise the available substrate). Changes in one or more of these drivers will influence the carbon budget of a peatland. How land management influences these drivers is unclear at present. Carbon budget calculations carried out by Worrall et al. (2003 and 2009) indicate that carbon dioxide and dissolved organic carbon (DOC) account for the greatest losses of carbon from peatland systems. If climate change predictions are realised, peatlands are expected to become sources of carbon as rising temperatures and falling water tables will result in increased rates of carbon mineralisation and subsequent losses of carbon. By investigating the influence of land management on these key carbon loss pathways, more accurate predictions of the effects of climate change on UK peatlands can be made. A field study was carried out in the British uplands to determine how carbon losses vary between differently managed peatlands, and to identify some of the underlying causes for such variations. The study focused on three of the driving factors identified by Laiho (2006): substrate quality, environmental conditions and nutrients. In addition, the physical properties of the peat - bulk density and air filled porosity which will control rates of gas and water movement within the peat profile, were studied. This paper will present the results of the work which was carried out at the Moor House, National Nature Reserve. The work involved collection of peat cores from burnt, grazed, drained, afforested and unmanaged areas of peat. The chemical and physical properties of the peat that are relevant to carbon cycling (e.g. nutrients, metals, substrate quality, air filled porosity) were analysed and compared between sites, and correlated with carbon losses which were measured on a fortnightly basis; and meteorological and hydrological data which were collected throughout the study period. Based on these results, suggestions for peatland management strategies that preserve carbon stocks will be presented. Laiho, R. (2006) "Decomposition in peatlands: Reconciling seemingly contrasting results on the impacts of lowered water levels." Soil Biology & Biochemistry 38(8): 2011-2024. Worrall, F. et al. (2003) "Carbon budget for a British upland peat catchment." Science of the Total Environment 312(1-3): 133-146. Worrall, F. et al. (2009) "The Multi-Annual Carbon Budget of a Peat-Covered Catchment" Science of the Total Environment 407: 4084-4094

Gaseous mercury fluxes in peatlands and the potential influence of climate change

NASA Astrophysics Data System (ADS)

Haynes, Kristine M.; Kane, Evan S.; Potvin, Lynette; Lilleskov, Erik A.; Kolka, Randall K.; Mitchell, Carl P. J.

2017-04-01

Climate change has the potential to significantly impact the stability of large stocks of mercury (Hg) stored in peatland systems due to increasing temperatures, altered water table regimes and subsequent shifts in vascular plant communities. However, the Hg exchange dynamics between the atmosphere and peatlands are not well understood. At the PEATcosm Mesocosm Facility in Houghton, Michigan, total gaseous Hg (TGM) fluxes were monitored in a subset of 1-m3 peat monoliths with altered water table positions (high and low) and vascular plant functional groups (sedge only, Ericaceae only or unmanipulated control) above the Sphagnum moss layer. At the SPRUCE bog in north-central Minnesota, TGM fluxes were measured from plots subjected to deep peat soil warming (up to +9 °C above ambient at a depth of 2 m). At PEATcosm, the strongest depositional trend was observed with the Low WT - sedge only treatment mesocosms with a mean TGM flux of -73.7 ± 6.3 ng m-2 d-1, likely due to shuttling of Hg to the peat at depth by aerenchymous tissues. The highest total leaf surface and tissue Hg concentrations were observed with the Ericaceae shrubs. A negative correlation between TGM flux and Ericaceae total leaf surface area suggests an influence of shrubs in controlling Hg exchange through stomatal uptake, surface sorption and potentially, peat shading. Surface peat total Hg concentrations are highest in treatments with greatest deposition suggesting deposition controls Hg accumulation in surface peat. Fluxes in the SPRUCE plots ranged from -45.9 ± 93.8 ng m-2 d-1 prior to the implementation of the deep warming treatments to -1.41 ± 27.1 ng m-2 d-1 once warming targets were achieved at depth and +10.2 ± 44.6 ng m-2 d-1 following prolonged deep soil warming. While these intervals did not differ significantly, a significant positive increase in the slope of the regression between flux and surface temperature was observed across the pre-treatment and warming periods. Shifts in vascular vegetation cover and peat warming as a result of climate change may significantly affect the dynamics of TGM fluxes between peatlands and the atmosphere.

Quantifying spatial variability of depth of peat burn in wetlands in relation to antecedent characteristics using field data, multi-temporal and multi-spectral LiDAR

NASA Astrophysics Data System (ADS)

Chasmer, L.; Flade, L.; Virk, R.; Montgomery, J. S.; Hopkinson, C.; Thompson, D. K.; Petrone, R. M.; Devito, K.

2017-12-01

Landscape changes in the hydrological characteristics of wetlands in some parts of the Boreal region of Canada are occurring as a result of climate-induced feedbacks and anthropogenic disturbance. Wetlands are largely resilient to wildfire, however, natural, climatic and anthropogenic disturbances can change surface water regimes and predispose wetlands to greater depth of peat burn. Over broad areas, peat loss contributes to significant pollution emissions, which can affect community health. In this study, we a) quantify depth of peat burn and relationships to antecedent conditions (species type, topography, surficial geology) within three classified wetlands found in the Boreal Plains ecoregion of western Canada; and b) examine the impacts of wildfire on post-fire ground surface energy balance to determine how peat loss might affect local hydro-climatology and surface water feedbacks. High-resolution optical imagery, pre- and post-burn multi-spectral Light Detection And Ranging (LiDAR), airborne thermal infrared imagery, and field validation data products are integrated to identify multiple complex interactions within the study wetlands. LiDAR-derived depth of peat burn is within 1 cm (average) compared with measured (RMSE = 9 cm over the control surface), demonstrating the utility of LiDAR with high point return density. Depth of burn also correlates strongly with variations in Normalised Burn Ratio (NBR) determined for ground surfaces only. Antecedent conditions including topographic position, soil moisture, soil type and wetland species also have complex interactions with depth of peat loss within wetlands observed in other studies. However, while field measurements are important for validation and understanding eco-hydrological processes, results from remote sensing are spatially continuous. Temporal LiDAR data illustrate the full range of variability in depth of burn and wetland characteristics following fire. Finally, measurements of instantaneous surface temperature indicate that the temperatures of burned wetlands are significantly warmer by up to 10oC compared to non-burned wetlands, altering locally variable sensible vs. latent energy exchanges and implications for further post-fire evaporative losses.

River Export of Dissolved and Particulate Organic Carbon from Permafrost and Peat Deposits across the Siberian Arctic

NASA Astrophysics Data System (ADS)

Wild, B.; Andersson, A.; Bröder, L.; Vonk, J.; Hugelius, G.; McClelland, J. W.; Raymond, P. A.; Gustafsson, O.

2017-12-01

Permafrost and peat deposits of northern high latitudes store more than 1300 Pg of organic carbon. This carbon has been preserved for thousands of years by cold and moist conditions, but is now increasingly mobilized as temperatures rise. While part will be degraded to CO2 and CH4 and amplify global warming, part will be exported by rivers to the Arctic Ocean where it can be degraded or re-buried by sedimentation. We here use the four large Siberian rivers Ob, Yenisey, Lena, and Kolyma as natural integrators of carbon mobilization in their catchments. We apply isotope based source apportionments and Markov Chain Monte Carlo Simulations to quantify contributions of organic carbon from permafrost and peat deposits to organic carbon exported by these rivers. More specifically, we compare the 14C signatures of dissolved and particulate organic carbon (DOC, POC) sampled close to the river mouths with those of five potential carbon sources; (1) recent aquatic and (2) terrestrial primary production, (3) the active layer of permafrost soils, (4) deep Holocene deposits (including thermokarst and peat deposits) and (5) Ice Complex Deposits. 14C signatures of these endmembers were constrained based on extensive literature review. We estimate that the four rivers together exported 2.4-4.5 Tg organic carbon from permafrost and peat deposits per year. While total organic carbon export was dominated by DOC (90%), the export of organic carbon from permafrost and peat deposits was more equally distributed between DOC (56%) and POC (44%). Recent models predict that ca. 200 Pg carbon will be lost as CO2 or CH4 by 2100 (RCP8.5) from the circumarctic permafrost area, of which roughly a quarter is drained by the Ob, Yenisey, Lena, and Kolyma rivers. Our comparatively low estimates of river carbon export thus suggest limited transfer of organic carbon from permafrost and peat deposits to high latitude rivers, or its rapid degradation within rivers. Our findings highlight the importance of both DOC and POC, and its degradation, for the fate of carbon mobilized from high latitude deposits under global warming, and indicate a low potential for its stabilization in the Arctic Ocean.

Vertical Stratification of Peat Pore Water Dissolved Organic Matter Composition in a Peat Bog in Northern Minnesota: Pore Water DOM composition in a peat bog

DOE PAGES

Tfaily, Malak M.; Wilson, Rachel M.; Cooper, William T.; ...

2018-01-29

Here, we characterized dissolved organic matter (DOM) composition throughout the peat column at the Marcell S1 forested bog in northern Minnesota and tested the hypothesis that redox oscillations associated with cycles of wetting and drying at the surface of the fluctuating water table correlate with increased carbon, sulfur, and nitrogen turn over. We found significant vertical stratification of DOM molecular composition and excitation-emission matrix parallel factor analysis components within the peat column. In particular, the intermediate depth zone (~ 50 cm) was identified as a zone where maximum decomposition and turnover is taking place. Surface DOM was dominated by inputsmore » from surface vegetation. The intermediate depth zone was an area of high organic matter reactivity and increased microbial activity with diagenetic formation of many unique compounds, among them polycyclic aromatic compounds that contain both nitrogen and sulfur heteroatoms. These compounds have been previously observed in coal-derived compounds and were assumed to be responsible for coal's biological activity. Biological processes triggered by redox oscillations taking place at the intermediate depth zone of the peat profile at the S1 bog are assumed to be responsible for the formation of these heteroatomic PACs in this system. Alternatively, these compounds could stem from black carbon and nitrogen derived from fires that have occurred at the site in the past. Surface and deep DOM exhibited more similar characteristics, compared to the intermediate depth zone, with the deep layer exhibiting greater input of microbially degraded organic matter than the surface suggesting that the entire peat profile consists of similar parent material at different degrees of decomposition and that lateral and vertical advection of pore water from the surface to the deeper horizons is responsible for such similarities. Lastly, our findings suggest that molecular composition of DOM in peatland pore water is dynamic and is a function of ecosystem activity, water table, redox oscillation, and pore water advection.« less

Vertical Stratification of Peat Pore Water Dissolved Organic Matter Composition in a Peat Bog in Northern Minnesota: Pore Water DOM composition in a peat bog

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tfaily, Malak M.; Wilson, Rachel M.; Cooper, William T.

Here, we characterized dissolved organic matter (DOM) composition throughout the peat column at the Marcell S1 forested bog in northern Minnesota and tested the hypothesis that redox oscillations associated with cycles of wetting and drying at the surface of the fluctuating water table correlate with increased carbon, sulfur, and nitrogen turn over. We found significant vertical stratification of DOM molecular composition and excitation-emission matrix parallel factor analysis components within the peat column. In particular, the intermediate depth zone (~ 50 cm) was identified as a zone where maximum decomposition and turnover is taking place. Surface DOM was dominated by inputsmore » from surface vegetation. The intermediate depth zone was an area of high organic matter reactivity and increased microbial activity with diagenetic formation of many unique compounds, among them polycyclic aromatic compounds that contain both nitrogen and sulfur heteroatoms. These compounds have been previously observed in coal-derived compounds and were assumed to be responsible for coal's biological activity. Biological processes triggered by redox oscillations taking place at the intermediate depth zone of the peat profile at the S1 bog are assumed to be responsible for the formation of these heteroatomic PACs in this system. Alternatively, these compounds could stem from black carbon and nitrogen derived from fires that have occurred at the site in the past. Surface and deep DOM exhibited more similar characteristics, compared to the intermediate depth zone, with the deep layer exhibiting greater input of microbially degraded organic matter than the surface suggesting that the entire peat profile consists of similar parent material at different degrees of decomposition and that lateral and vertical advection of pore water from the surface to the deeper horizons is responsible for such similarities. Lastly, our findings suggest that molecular composition of DOM in peatland pore water is dynamic and is a function of ecosystem activity, water table, redox oscillation, and pore water advection.« less

46 CFR 148.290 - Peat moss.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 5 2011-10-01 2011-10-01 false Peat moss. 148.290 Section 148.290 Shipping COAST GUARD... SPECIAL HANDLING Special Requirements for Certain Materials § 148.290 Peat moss. (a) Before shipment, peat... handling or coming into contact with peat moss must wear gloves, a dust mask, and goggles. ...

Exposing ecological and economic costs of the research-implementation gap and compromises in decision making.

PubMed

Kareksela, Santtu; Moilanen, Atte; Ristaniemi, Olli; Välivaara, Reima; Kotiaho, Janne S

2018-02-01

The frequently discussed gap between conservation science and practice is manifest in the gap between spatial conservation prioritization plans and their implementation. We analyzed the research-implementation gap of one zoning case by comparing results of a spatial prioritization analysis aimed at avoiding ecological impact of peat mining in a regional zoning process with the final zoning plan. We examined the relatively complex planning process to determine the gaps among research, zoning, and decision making. We quantified the ecological costs of the differing trade-offs between ecological and socioeconomic factors included in the different zoning suggestions by comparing the landscape-level loss of ecological features (species occurrences, habitat area, etc.) between the different solutions for spatial allocation of peat mining. We also discussed with the scientists and planners the reasons for differing zoning suggestions. The implemented plan differed from the scientists suggestion in that its focus was individual ecological features rather than all the ecological features for which there were data; planners and decision makers considered effects of peat mining on areas not included in the prioritization analysis; zoning was not truly seen as a resource-allocation process and not emphasized in general minimizing ecological losses while satisfying economic needs (peat-mining potential); and decision makers based their prioritization of sites on site-level information showing high ecological value and on single legislative factors instead of finding a cost-effective landscape-level solution. We believe that if the zoning and decision-making processes are very complex, then the usefulness of science-based prioritization tools is likely to be reduced. Nevertheless, we found that high-end tools were useful in clearly exposing trade-offs between conservation and resource utilization. © 2017 Society for Conservation Biology.

A debris flow deposit in alluvial, coal-bearing facies, Bighorn Basin, Wyoming, USA: Evidence for catastrophic termination of a mire

USGS Publications Warehouse

Roberts, S.B.; Stanton, R.W.; Flores, R.M.

1994-01-01

Coal and clastic facies investigations of a Paleocene coal-bearing succession in the Grass Creek coal mine, southwestern Bighorn Basin, Wyoming, USA, suggest that disruption of peat accumulation in recurrent mires was caused by the repetitive progradation of crevasse splays and, ultimately, by a catastrophic mass movement. The mass movement, represented by deposits of debris flow, marked the termination of significant peat accumulation in the Grass Creek coal mine area. Megascopic and microscopic analyses of coal beds exposed along the mine highwalls suggest that these deposits developed in low-lying mires, as evidenced primarily by their ash yields and maceral composition. Disruption of peat accumulation in successive mires was caused by incursions of sediment into the mire environments. Termination by crevasse splay progradation is represented by coarsening-upward successions of mudrock and tabular, rooted sandstone, which overlie coal beds in the lower part of the coal-bearing interval. A more rapid process of mire termination by mass movement is exemplified by a debris flow deposit of diamictite, which overlies the uppermost coal bed at the top of the coal-bearing interval. The diamictite consists of a poorly sorted, unstratified mixture of quartzite cobbles and pebbles embedded in a claystone-rich or sandy mudstone matrix. Deposition of the diamictite may have taken place over a matter of weeks, days, or perhaps even hours, by catastrophic flood, thus reflecting an instantaneous process of mire termination. Coarse clastics and mud were transported from the southwest some 20-40 km as a viscous debris flow along stream courses from the ancestral Washakie Range to the Grass Creek area, where the flow overrode a low-lying mire and effectively terminated peat accumulation. ?? 1994.

Storage dynamics in hydropedological units control hillslope connectivity, runoff generation, and the evolution of catchment transit time distributions

PubMed Central

Tetzlaff, D; Birkel, C; Dick, J; Geris, J; Soulsby, C

2014-01-01

We examined the storage dynamics and isotopic composition of soil water over 12 months in three hydropedological units in order to understand runoff generation in a montane catchment. The units form classic catena sequences from freely draining podzols on steep upper hillslopes through peaty gleys in shallower lower slopes to deeper peats in the riparian zone. The peaty gleys and peats remained saturated throughout the year, while the podzols showed distinct wetting and drying cycles. In this region, most precipitation events are <10 mm in magnitude, and storm runoff is mainly generated from the peats and peaty gleys, with runoff coefficients (RCs) typically <10%. In larger events the podzolic soils become strongly connected to the saturated areas, and RCs can exceed 40%. Isotopic variations in precipitation are significantly damped in the organic-rich soil surface horizons due to mixing with larger volumes of stored water. This damping is accentuated in the deeper soil profile and groundwater. Consequently, the isotopic composition of stream water is also damped, but the dynamics strongly reflect those of the near-surface waters in the riparian peats. “pre-event” water typically accounts for >80% of flow, even in large events, reflecting the displacement of water from the riparian soils that has been stored in the catchment for >2 years. These riparian areas are the key zone where different source waters mix. Our study is novel in showing that they act as “isostats,” not only regulating the isotopic composition of stream water, but also integrating the transit time distribution for the catchment. Key Points Hillslope connectivity is controlled by small storage changes in soil units Different catchment source waters mix in large riparian wetland storage Isotopes show riparian wetlands set the catchment transit time distribution PMID:25506098

Peatland Open-water Pool Biogeochemistry: The Influence of Hydrology and Vegetation

NASA Astrophysics Data System (ADS)

Arsenault, J.; Talbot, J.; Moore, T. R.

2017-12-01

Peatland open-water pools are net sources of carbon to the atmosphere. However, their interaction with the surrounding peat remains poorly known. In a previous study, we showed that shallow pools are richer in nutrients than deep pools. While depth was the main driver of biogeochemistry variations across time and space, analyses also showed that pool's adjacent vegetation may have an influence on water chemistry. Our goal is to understand the relationship between the biogeochemistry of open-water pools and their surroundings in a subboreal ombrotrophic peatland of southern Quebec (Canada). To assess the influence of vegetation on pool water chemistry, we compare two areas covered with different types of vegetation: a forested zone dominated by spruce trees and an open area mostly covered by Sphagnum spp. To evaluate the direction of water (in or out of the pools), we installed capacitance water level probes in transects linking pools in the two zones. Wells were also installed next to each probe to collect peat pore water samples. Samples were taken every month during summer 2017 and analyzed for dissolved organic carbon, nitrogen and phosphorus, pH and specific UV absorbance. Preliminary results show differences in peat water chemistry depending on the dominant vegetation. In both zones, water levels fluctuations are disconnected between peat and the pools, suggesting poor horizontal water movement. Pool water chemistry may be mostly influenced by the immediate surrounding vegetation than by the local vegetation pattern. Climate and land-use change may affect the vegetation structure of peatlands, thus affecting pool biogeochemistry. Considering the impact of pools on the overall peatland capacity to accumulate carbon, our results show that more focus must be placed on pools to better understand peatland stability over time.

Storage dynamics in hydropedological units control hillslope connectivity, runoff generation, and the evolution of catchment transit time distributions.

PubMed

Tetzlaff, D; Birkel, C; Dick, J; Geris, J; Soulsby, C

2014-02-01

We examined the storage dynamics and isotopic composition of soil water over 12 months in three hydropedological units in order to understand runoff generation in a montane catchment. The units form classic catena sequences from freely draining podzols on steep upper hillslopes through peaty gleys in shallower lower slopes to deeper peats in the riparian zone. The peaty gleys and peats remained saturated throughout the year, while the podzols showed distinct wetting and drying cycles. In this region, most precipitation events are <10 mm in magnitude, and storm runoff is mainly generated from the peats and peaty gleys, with runoff coefficients (RCs) typically <10%. In larger events the podzolic soils become strongly connected to the saturated areas, and RCs can exceed 40%. Isotopic variations in precipitation are significantly damped in the organic-rich soil surface horizons due to mixing with larger volumes of stored water. This damping is accentuated in the deeper soil profile and groundwater. Consequently, the isotopic composition of stream water is also damped, but the dynamics strongly reflect those of the near-surface waters in the riparian peats. "pre-event" water typically accounts for >80% of flow, even in large events, reflecting the displacement of water from the riparian soils that has been stored in the catchment for >2 years. These riparian areas are the key zone where different source waters mix. Our study is novel in showing that they act as "isostats," not only regulating the isotopic composition of stream water, but also integrating the transit time distribution for the catchment. Hillslope connectivity is controlled by small storage changes in soil unitsDifferent catchment source waters mix in large riparian wetland storageIsotopes show riparian wetlands set the catchment transit time distribution.

Size and XAD fractionations of trihalomethane precursors from soils.

PubMed

Chow, Alex T; Guo, Fengmao; Gao, Suduan; Breuer, Richard S

2006-03-01

Soil organic matter is an important source of allochthonous dissolved organic matter inputs to the Sacramento-San Joaquin Delta waterways, which is a drinking water source for 22 million people in California, USA. Knowledge of trihalomethane (THM) formation potential of soil-derived organic carbon is important for developing effective strategies for organic carbon removal in drinking water treatment. In this study, soil organic carbon was extracted with electrolytes (deionized H2O and Na- or Ca-based electrolytes) of electrical conductivity bracketing those found in Delta leaching and runoff conditions. The extracts were physically and chemically separated into different fractions: colloidal organic carbon (0.45-0.1 microm), fine colloidal organic carbon (0.1-0.025 microm), and dissolved organic carbon (DOC) (<0.025 microm); hydrophobic acid (HPOA), transphilic acid, and hydrophilic acid. Two representative Delta soils, Rindge Muck (a peat soil) and Scribner Clay Loam (a mineral soil) were examined. Results showed that less than 2% of soil organic carbon was electrolyte-extractable and heterogeneous organic fractions with distinct THM reactivity existed. Regardless of soil and electrolytes, DOC and HPOA fractions were dominant in terms of total concentration and THMFP. The amounts of extractable organic carbon and THMFP were dependent on the cation and to a lesser extent on electrical conductivity of electrolytes. Along with our previous study on temperature and moisture effects on DOC production, we propose a conceptual model to describe the impacts of agricultural practices on DOC production in the Delta. DOC is mainly produced in the surface peat soils during the summer and is immobilized by accumulated salt in the soils. DOC is leached from soils to drainage ditches and finally to the Delta channels during winter salt leaching practices.

Modelling global CO2 emissions into the atmosphere from crown, ground, and peat fires

NASA Astrophysics Data System (ADS)

Eliseev, Alexey V.; Mokhov, Igor I.; Chernokulsky, Alexander V.

2015-04-01

The scheme for natural fires implemented in the climate model (CM) developed at the A.M. Obukhov Institute of Atmospheric Physics (IAP RAS) is extended by a module accounting for ground and peat fires. With the IAP RAS CM, the simulations are performed for 1700-2300 in accordance with the CMIP5 (Coupled Models Intercomparison Project, phase 5) protocol. The modelled present-day burnt area, BA, and the corresponding CO2 emissions into the atmosphere E agree with the GFED-3.1 estimates at most regions. In the 21st century, under the RCP (Representative Concentration Pathways) scenarios, the global BA increases by 10-41% depending on scenario, and E increases by 11-39%. Under the mitigation scenario RCP 2.6, both BA and E slightly decrease in the 22nd-23rd centuries. For scenarios RCP 4.5, RCP 6.0, and RCP 8.5, they continue to increase in these two centuries. All these changes are mostly due to changes in natural fires activity in the boreal regions. Ground and peat fires contribute significantly to the total emissions of CO2 from natural fires (20-25% at the global scale depending on scenario and calendar year). Peat fires markedly intensify interannual variability of regional CO2 emissions from natural fires.

Trends and causes of historical wetland loss, Sabine National Wildlife Refuge, southwest Louisiana

USGS Publications Warehouse

Bernier, Julie C.; Morton, Robert A.; Kelso, Kyle W.

2011-01-01

The thickness of the uppermost Holocene sediments (peat and organic-rich mud) and the elevation of stratigraphic contacts were compared at marsh and open-water sites across areas of formerly continuous marsh to estimate magnitudes of recent elevation loss caused by vertical erosion and subsidence. Results of these analyses indicate that erosion greatly exceeded subsidence at most of the core sites, although both processes have contributed to historical wetland loss. Comparison of these results with results of our prior studies indicates that magnitudes of subsidence and total accommodation space that formed in the western chenier plain were less than those in the delta plain. Compared with the delta plain, where subsidence generally exceeded erosion and peat thicknesses were so great that peat was preserved even where erosion was greater than subsidence, the SNWR peats are thin and were absent (eroded) at most open-water sites. Although historical subsidence rates in the chenier plain are substantially lower than most of the same rates in the delta plain, the temporal and spatial trends of rapid wetland loss, highest rates of land-surface subsidence, and high rates of oil-and-gas production are similar, indicating that historical wetland loss was likely initiated by similar processes (deep-subsurface subsidence) in both regions.

Maceral and palynomorph facies from two tertiary peat-forming environments in the Powder River Basin, U.S.A.

USGS Publications Warehouse

Moore, T.A.; Stanton, R.W.; Pocknall, D.T.; Glores, R.M.

1990-01-01

The differences between the depositional settings of the Smith and Anderson subbituminous coal beds (Paleocene, central Powder River Basin, U.S.A.) are interpreted on the basis of their petrographic composition and palynologic assemblages. The Smith coal bed is relatively thin ( 50 m) sandstone bodies of an abandoned meander-belt complex, the coal bed is generally thicker (> 7 m) and more widespread (> 15 km) in extent than the Smith coal bed. The sands provided a relatively stable, poorly compactable platform that was favorable to the growth of large, arborescent vegetation, such as the dominant ancestral Glyptostrobus, as well as ancestral Nyssa, Carya, and Betulaceae in a well-drained but moist swamp environment. The stability of the peat-forming environment resulted in a raised peat deposit of relatively uniform paleoflora and peat composition. In the thicker areas of the Anderson coal bed, the upward increase in carbonized plant components indicates a progressively drier or better-drained swamp environment. Intervals within the coal bed that overlie or are lateral to crevasse-splay deposits contain a high concentration of pollen attributable to Pterocarya and an absence of carbonized plant remains, an indication that ancestral Pterocarya preferred a water-saturated environment close to the edge of the swamp where detrial influx occurred. ?? 1990.

Vegetation correlates of gibbon density in the peat-swamp forest of the Sabangau catchment, Central Kalimantan, Indonesia.

PubMed

Hamard, Marie; Cheyne, Susan M; Nijman, Vincent

2010-06-01

Understanding the complex relationship between primates and their habitats is essential for effective conservation plans. Peat-swamp forest has recently been recognized as an important habitat for the Southern Bornean gibbon (Hylobates albibarbis), but information is scarce on the factors that link gibbon density to characteristics of this unique ecosystem. Our aims in this study were firstly to estimate gibbon density in different forest subtypes in a newly protected, secondary peat-swamp forest in the Sabangau Catchment, Indonesia, and secondly to identify which vegetation characteristics correlate with gibbon density. Data collection was conducted in a 37.1 km(2) area, using auditory sampling methods and vegetation "speed plotting". Gibbon densities varied between survey sites from 1.39 to 3.92 groups/km(2). Canopy cover, tree height, density of large trees and food availability were significantly correlated with gibbon density, identifying the preservation of tall trees and good canopy cover as a conservation priority for the gibbon population in the Sabangau forest. This survey indicates that selective logging, which specifically targets large trees and disrupts canopy cover, is likely to have adverse effects on gibbon populations in peat-swamp forests, and calls for greater protection of these little-studied ecosystems. (c) 2010 Wiley-Liss, Inc.

Symbiotic potential and survival of native rhizobia kept on different carriers

PubMed Central

Ruíz-Valdiviezo, Víctor Manuel; Canseco, Lucía María Cristina Ventura; Suárez, Luis Antonio Castillo; Gutiérrez-Miceli, Federico Antonio; Dendooven, Luc; Rincón-Rosales, Reiner

2015-01-01

Native rhizobia are ideal for use as commercial legume inoculants. The characteristics of the carrier used to store the inoculants are important for the survival and symbiotic potential of the rhizobia. The objective of this study was to investigate the effects of peat (PEAT), perlite sugarcane bagasse (PSB), carboxymethyl cellulose plus starch (CMCS), and yeast extract mannitol supplemented with mannitol (YEMM) on the survival, nodulation potential and N2 fixation capacity of the native strains Sinorhizobium mexicanum ITTG R7T and Rhizobium calliandrae LBP2-1T and of the reference strain Rhizobium etli CFN42T. A factorial design (4 × 3) with four repetitions was used to determine the symbiotic potential of the rhizobial strains. The survival of the strains was higher for PEAT (46% for strain LBP2-1T, 167% for strain CFN42T and 219% for strain ITTG R7T) than for the other carriers after 240 days, except for CFN42T kept on CMCS (225%). All the strains kept on the different carriers effectively nodulated common bean, with the lowest number of nodules found (5 nodules) when CFN42T was kept on CMCS and with the highest number of nodules found (28 nodules) when ITTG R7T was kept on PSB. The nitrogenase activity was the highest for ITTG R7T kept on PEAT (4911 μmol C2H4 per fresh weight nodule h−1); however, no activity was found when the strains were kept on YEMM. Thus, the survival and symbiotic potential of the rhizobia depended on the carrier used to store them. PMID:26413054

Multi-year net ecosystem carbon balance at a horticulture-extracted restored peatland

NASA Astrophysics Data System (ADS)

Nugent, Kelly; Strachan, Ian; Strack, Maria

2017-04-01

Restoration of previously extracted peatlands is essential to minimize the impact of drainage and peat removal. Best practices restoration methods have been developed that include ditch blocking, site leveling and reintroducing bog vegetation using the moss layer transfer technique. A long term goal of restoration is the return to a peat accumulating ecosystem. Bois-des-Bel is a cool-temperate bog, located in eastern Quebec, Canada, that was vacuum harvested until 1980 and restored in 1999. While several studies have used discrete (chamber) methods to determine the net carbon exchange from rewetted or restored peatlands, ours appears to be the first to have multiple complete years of net ecosystem carbon exchange from a restored northern peatland. An eddy covariance flux tower instrumented with a sonic anemometer and open-path CO2/H2O and CH4 analyzers was operated continuously over three years to produce a robust estimate of net carbon sequestration. Our initial results indicate that this restored peatland was a consistent moderate annual net sink for CO2, a moderate source of CH4 and had low losses of dissolved organic carbon compared to undisturbed northern latitude peatlands. Closed chambers combined with a fast response CO2/H2O/CH4 analyzer were used to investigate ecohydrological controls on net ecosystem exchange of CO2 (NEE) and CH4 flux from the restored fields and remnant ditches at the site. CH4 release was found to be an order of magnitude higher in the ditches compared to the fields, with non-vegetated ditch showing a greater range in flux compared to areas invaded by Typha latifolia. Bubble magnitude and count were highest in the non-vegetated ditch, followed by Typha plots and were undetectable in the restored fields. The latter may be partially attributed to the high cover of Eriophorum vaginatum in the restored fields, plants that have aerenchymous tissue, as well as a much deeper water table level. While the non-vegetated ditch areas were a steady small source of CO2, NEE in the Typha plots showed significantly greater CO2 uptake capacity relative to any other restored plant community. High productivity combined with reduced CH4 flux suggests that Typha may be playing a key role in reducing the overall impact of the remnant ditches on the net ecosystem carbon balance. A preliminary footprint analysis suggests that ecosystem-level CH4 flux is being primarily driven by release from hotspots while the majority of the tower source area is a very small source of methane.

Terrestrial Responses to Variability in the Southern Westerlies Inferred from Deep Holocene Peat Archives

NASA Astrophysics Data System (ADS)

Hughes, P. D. M.; Mauquoy, D.; van Bellen, S.; Roland, T. P.; Loader, N.; Street-Perrott, F. A.; Daley, T.

2017-12-01

The deep ombrotrophic peat bogs of Chile are located throughout the latitudes dominated by the southern westerly wind belt. The domed surfaces of these peatlands make them sensitive to variability in summer atmospheric moisture balance and the near-continuous accumulation of deep peat strata throughout the Holocene to the present day means that these sites provide undisturbed archives of palaeoclimatic change. We have reconstructed late-Holocene bog water table depths - which can be related to changes in the regional balance of precipitation to evaporation (P-E) - from a suite of peat bogs located in three areas of Tierra del Feugo, Chile, under the main path of the SWWB. Water-table depths were reconstructed from sub-fossil testate amoebae assemblages using a conventional transfer function to infer past water-table depths, based on taxonomic classification of tests but also an innovative trait-based transfer function to infer the same parameter. Water table reconstructions derived from the two methods were consistent within sites. They show that mire water tables have been relatively stable in the last 2000 years across Tierra del Feugo. Higher water table levels, most probably indicating increased effective precipitation, were found between c. 1400 and 900 cal. BP., whereas a consistent drying trend was reconstructed across the region in the most recent peat strata. This shift may represent a pronounced regional decrease in precipitation and/or a change to warmer conditions linked to strengthening of the SWWB. However, other factors such as recent thinning of the ozone layer over Tierra del Fuego could have contributed to recent shifts in some testate amoebae species.

The Burning of Surface and Deep Peat during Boreal Forest and Peatland Fires: Implications for Fire Behaviour and Global Carbon Cycling

NASA Astrophysics Data System (ADS)

Turetsky, M. R.

2015-12-01

Fire is increasingly appreciated as a threat to peatlands and their carbon stocks. The global peatland carbon pool exceeds that of global vegetation and is similar to the current atmospheric carbon pool. Under pristine conditions, most of the peat carbon stock is protected from burning, and resistance to fire has increased peat carbon storage in high latitude regions over long time scales. This, in part, is due to the high porosity and storage coefficient of surface peat, which minimizes water table variability and maintains wet conditions even during drought. However, higher levels of disturbance associated with warming and increasing human activities are triggering state changes and the loss of resiliency in some peatland systems. This presentation will summarize information on burn area and severity in peatlands under undisturbed scenarios of hydrologic self-regulation, and will assess the consequences of warming and drying on peatland vegetation and wildfire behaviour. Our goal is to predict where and when peatlands will become more vulnerable to deep smouldering, given the importance of deep peat layers to global carbon cycling, permafrost stability, and a variety of other ecosystem services in northern regions. Results from two major wildfire seasons (2004 in Alaska and 2014 in the Northwest Territories) show that biomass burning in peatlands releases similar amounts of carbon to the atmosphere as patterns of burning in upland forests, but that peatlands are less vulnerable to severe burning that tends to occur in boreal forests during late season fire activity.

The structure of the microbial communities in low-moor and high-moor peat bogs of Tomsk oblast

NASA Astrophysics Data System (ADS)

Dobrovol'skaya, T. G.; Golovchenko, A. V.; Kukharenko, O. S.; Yakushev, A. V.; Semenova, T. A.; Inisheva, L. A.

2012-03-01

The number, structure, and physical state of the microbial communities in high-moor and low-moor peat bogs were compared. Distinct differences in these characteristics were revealed. The microbial biomass in the high-moor peat exceeded that in the low-moor peat by 2-9 times. Fungi predominated in the high-moor peat, whereas bacteria were the dominant microorganisms in the low-moor peat. The micromycetal complexes of the high-moor peat were characterized by a high portion of dark-colored representatives; the complexes of the low-moor peat were dominated by fast-growing fungi. The species of the Penicillum genus were dominant in the high-moor peat; the species of Trichoderma were abundant in the low-moor peat. In the former, the bacteria were distinguished as minor components; in the latter, they predominated in the saprotrophic bacterial complex. In the high-moor peat, the microorganisms were represented by bacilli, while, in the low-moor peat, by cytophages, myxobacteria, and actinobacteria. The different physiological states of the bacteria in the studied objects reflecting the duration of the lag phase and the readiness of the metabolic system to consume different substrates were demonstrated for the first time. The relationships between the trophic characteristics of bacterial habitats and the capacity of the bacteria to consume substrates were established.

Experimental Investigation of the Deepening of the Combustion Front into Peat Layers Different in Botanical Composition

NASA Astrophysics Data System (ADS)

Kasymov, D. P.

2017-01-01

The deepening of the center of combustion into peat layers of different botanical compositions (pine-cotton grass and grass-sphagnum peats), typical for the Tomsk region, was investigated experimentally. Peats were ignited from a model ground forest fire initiated by firing of a needle-litter layer. As a result of laboratory investigations, the change in the temperature in the bulk of peat samples with time was determined and analyzed, and the rates of their combustion in the horizontal and vertical directions were estimated. It was established that a fire penetrates deep into a layer of grass-sphagnum peat, containing more than 70% of combustion conductors in its composition, more rapidly as compared to that of pine-cotton grass peat. The rates of combustion of grass-sphagnum peat in the vertical and horizontal directions are larger by 20 and 22%, respectively, than those of pine-cotton grass peat, which is evidently due to the botanical composition of grass-sphagnum peat and the random arrangement of components in its layers.

Deformation behaviors of peat with influence of organic matter.

PubMed

Yang, Min; Liu, Kan

2016-01-01

Peat is a kind of special material rich in organic matter. Because of the high content of organic matter, it shows different deformation behaviors from conventional geotechnical materials. Peat grain has a non-negligible compressibility due to the presence of organic matter. Biogas can generate from peat and can be trapped in form of gas bubbles. Considering the natural properties of peat, a special three-phase composition of peat is described which indicates the existence of organic matter and gas bubbles in peat. A stress-strain-time model is proposed for the compression of organic matter, and the surface tension effect is considered in the compression model of gas bubbles. Finally, a mathematical model has been developed to simulate the deformation behavior of peat considering the compressibility of organic matter and entrapped gas bubbles. The deformation process is the coupling of volume variation of organic matter, gas bubbles and water drainage. The proposed model is used to simulate a series of peat laboratory oedometer tests, and the model can well capture the test results with reasonable model parameters. Effects of model parameters on deformation of peat are also analyzed.

Effects of spatial heterogeneity in moisture content on the horizontal spread of peat fires.

PubMed

Prat-Guitart, Nuria; Rein, Guillermo; Hadden, Rory M; Belcher, Claire M; Yearsley, Jon M

2016-12-01

The gravimetric moisture content of peat is the main factor limiting the ignition and spread propagation of smouldering fires. Our aim is to use controlled laboratory experiments to better understand how the spread of smouldering fires is influenced in natural landscape conditions where the moisture content of the top peat layer is not homogeneous. In this paper, we study for the first time the spread of peat fires across a spatial matrix of two moisture contents (dry/wet) in the laboratory. The experiments were undertaken using an open-top insulated box (22×18×6cm) filled with milled peat. The peat was ignited at one side of the box initiating smouldering and horizontal spread. Measurements of the peak temperature inside the peat, fire duration and longwave thermal radiation from the burning samples revealed important local changes of the smouldering behaviour in response to sharp gradients in moisture content. Both, peak temperatures and radiation in wetter peat (after the moisture gradient) were sensitive to the drier moisture condition (preceding the moisture gradient). Drier peat conditions before the moisture gradient led to higher temperatures and higher radiation flux from the fire during the first 6cm of horizontal spread into a wet peat patch. The total spread distance into a wet peat patch was affected by the moisture content gradient. We predicted that in most peat moisture gradients of relevance to natural ecosystems the fire self-extinguishes within the first 10cm of horizontal spread into a wet peat patch. Spread distances of more than 10cm are limited to wet peat patches below 160% moisture content (mass of water per mass of dry peat). We found that spatial gradients of moisture content have important local effects on the horizontal spread and should be considered in field and modelling studies. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Predicting drought propagation within peat layers using a three dimensionally explicit voxel based model

NASA Astrophysics Data System (ADS)

Condro, A. A.; Pawitan, H.; Risdiyanto, I.

2018-05-01

Peatlands are very vulnerable to widespread fires during dry seasons, due to availability of aboveground fuel biomass on the surface and belowground fuel biomass on the sub-surface. Hence, understanding drought propagation occurring within peat layers is crucial with regards to disaster mitigation activities on peatlands. Using a three dimensionally explicit voxel-based model of peatland hydrology, this study predicted drought propagation time lags into sub-surface peat layers after drought events occurrence on the surface of about 1 month during La-Nina and 2.5 months during El-Nino. The study was carried out on a high-conservation-value area of oil palm plantation in West Kalimantan. Validity of the model was evaluated and its applicability for disaster mitigation was discussed. The animations of simulated voxels are available at: goo.gl/HDRMYN (El-Nino 2015 episode) and goo.gl/g1sXPl (La-Nina 2016 episode). The model is available at: goo.gl/RiuMQz.

Using Multitemporal and Multispectral Airborne Lidar to Assess Depth of Peat Loss and Correspondence With a New Active Normalized Burn Ratio for Wildfires

NASA Astrophysics Data System (ADS)

Chasmer, L. E.; Hopkinson, C. D.; Petrone, R. M.; Sitar, M.

2017-12-01

Accuracy of depth of burn (an indicator of consumption) in peatland soils using prefire and postfire airborne light detection and ranging (lidar) data is determined within a wetland-upland forest environment near Fort McMurray, Alberta, Canada. The relationship between peat soil burn depth and an "active" normalized burn ratio (ANBR) is also examined beneath partially and fully burned forest and understory canopies using state-of-the-art active reflectance from a multispectral lidar compared with normalized burn ratio (NBR) derived from Landsat 7 ETM+. We find significant correspondence between depth of burn, lidar-derived ANBR, and difference NBR (dNBR) from Landsat. However, low-resolution optical imagery excludes peatland burn losses in transition zones, which are highly sensitive to peat loss via combustion. The findings presented here illustrate the utility of this new remote sensing technology for expanding an area of research where it has previously been challenging to spatially detect and quantify such wildfire burn losses.

Vertical Stratification of Peat Pore Water Dissolved Organic Matter Composition in a Peat Bog in Northern Minnesota

NASA Astrophysics Data System (ADS)

Tfaily, Malak M.; Wilson, Rachel M.; Cooper, William T.; Kostka, Joel E.; Hanson, Paul; Chanton, Jeffrey P.

2018-02-01

We characterized dissolved organic matter (DOM) composition throughout the peat column at the Marcell S1 forested bog in northern Minnesota and tested the hypothesis that redox oscillations associated with cycles of wetting and drying at the surface of the fluctuating water table correlate with increased carbon, sulfur, and nitrogen turn over. We found significant vertical stratification of DOM molecular composition and excitation-emission matrix parallel factor analysis components within the peat column. In particular, the intermediate depth zone ( 50 cm) was identified as a zone where maximum decomposition and turnover is taking place. Surface DOM was dominated by inputs from surface vegetation. The intermediate depth zone was an area of high organic matter reactivity and increased microbial activity with diagenetic formation of many unique compounds, among them polycyclic aromatic compounds that contain both nitrogen and sulfur heteroatoms. These compounds have been previously observed in coal-derived compounds and were assumed to be responsible for coal's biological activity. Biological processes triggered by redox oscillations taking place at the intermediate depth zone of the peat profile at the S1 bog are assumed to be responsible for the formation of these heteroatomic PACs in this system. Alternatively, these compounds could stem from black carbon and nitrogen derived from fires that have occurred at the site in the past. Surface and deep DOM exhibited more similar characteristics, compared to the intermediate depth zone, with the deep layer exhibiting greater input of microbially degraded organic matter than the surface suggesting that the entire peat profile consists of similar parent material at different degrees of decomposition and that lateral and vertical advection of pore water from the surface to the deeper horizons is responsible for such similarities. Our findings suggest that molecular composition of DOM in peatland pore water is dynamic and is a function of ecosystem activity, water table, redox oscillation, and pore water advection.

Caribbean mangroves adjust to rising sea level through biotic controls on change in soil elevation

USGS Publications Warehouse

McKee, K.L.; Cahoon, D.R.; Feller, Ilka C.

2007-01-01

Aim The long-term stability of coastal ecosystems such as mangroves and salt marshes depends upon the maintenance of soil elevations within the intertidal habitat as sea level changes. We examined the rates and processes of peat formation by mangroves of the Caribbean Region to better understand biological controls on habitat stability. Location Mangrove-dominated islands on the Caribbean coasts of Belize, Honduras and Panama were selected as study sites. Methods Biological processes controlling mangrove peat formation were manipulated (in Belize) by the addition of nutrients (nitrogen or phosphorus) to Rhizophora mangle (red mangrove), and the effects on the dynamics of soil elevation were determined over a 3-year period using rod surface elevation tables (RSET) and marker horizons. Peat composition and geological accretion rates were determined at all sites using radiocarbon-dated cores. Results The addition of nutrients to mangroves caused significant changes in rates of mangrove root accumulation, which influenced both the rate and direction of change in elevation. Areas with low root input lost elevation and those with high rates gained elevation. These findings were consistent with peat analyses at multiple Caribbean sites showing that deposits (up to 10 m in depth) were composed primarily of mangrove root matter. Comparison of radiocarbon-dated cores at the study sites with a sea-level curve for the western Atlantic indicated a tight coupling between peat building in Caribbean mangroves and sea-level rise over the Holocene. Main conclusions Mangroves common to the Caribbean region have adjusted to changing sea level mainly through subsurface accumulation of refractory mangrove roots. Without root and other organic inputs, submergence of these tidal forests is inevitable due to peat decomposition, physical compaction and eustatic sea-level rise. These findings have relevance for predicting the effects of sea-level rise and biophysical processes on tropical mangrove ecosystems.

234U/238U and δ87Sr in peat as tracers of paleosalinity in the Sacramento-San Joaquin Delta of California, USA

USGS Publications Warehouse

Drexler, Judith Z.; Paces, James B.; Alpers, Charles N.; Windham-Myers, Lisamarie; Neymark, Leonid; Bullen, Thomas D.; Taylor, Howard E.

2013-01-01

The purpose of this study was to determine the history of paleosalinity over the past 6000+ years in the Sacramento-San Joaquin Delta (the Delta), which is the innermost part of the San Francisco Estuary. We used a combination of Sr and U concentrations, d87Sr values, and 234U/238U activity ratios (AR) in peat as proxies for tracking paleosalinity. Peat cores were collected in marshes on Browns Island, Franks Wetland, and Bacon Channel Island in the Delta. Cores were dated using 137Cs, the onset of Pb and Hg contamination from hydraulic gold mining, and 14C. A proof of concept study showed that the dominant emergent macrophyte and major component of peat in the Delta, Schoenoplectus spp., incorporates Sr and U and that the isotopic composition of these elements tracks the ambient water salinity across the Estuary. Concentrations and isotopic compositions of Sr and U in the three main water sources contributing to the Delta (seawater, Sacramento River water, and San Joaquin River water) were used to construct a three-end-member mixing model. Delta paleosalinity was determined by examining variations in the distribution of peat samples through time within the area delineated by the mixing model. The Delta has long been considered a tidal freshwater marsh region, but only peat samples from Franks Wetland and Bacon Channel Island have shown a consistently fresh signal (<0.5 ppt) through time. Therefore, the eastern Delta, which occurs upstream from Bacon Channel Island along the San Joaquin River and its tributaries, has also been fresh for this time period. Over the past 6000+ years, the salinity regime at the western boundary of the Delta (Browns Island) has alternated between fresh and oligohaline (0.5-5 ppt).

Distinguishing local ecology from regional hydrologic change in a subtropical wetland, Florida Everglades USA

NASA Astrophysics Data System (ADS)

Bernhardt, C. E.; Willard, D. A.

2012-12-01

The Florida Everglades is a subtropical peatland where differences in bedrock topography, water depth, and hydroperiod affect the distribution and composition of vegetation communities. Previous studies have demonstrated that human modification of the natural hydrology and changes in precipitation associated with natural climate variability can alter the distribution wetland vegetation and influence whether a site is accumulating peat or marl. Pollen analysis of sediments from vegetation communities separated by only a few meters, like the ridges and sloughs, demonstrates the strong signature of the local community. However, over decadal to centennial scales, a broader regional climate response is documented in the pollen record. Here, we examine the sedimentary and pollen records from a suite of 42 cores to tease apart local and regional hydrologic patterns in the marl prairie wetland community. The marl prairie community, which covers an area of 190,000 ha, is a short hydroperiod wetland characterized by sparse vegetation and dominated by grasses and sedges. Pollen and geochronologic data from an earlier study suggested that changes in the vegetation (sawgrass marsh to prairie) and sediment type (peat to marl) were tied exclusively to 20th century water management. However, our results show a diverse assemblage of sediment profiles include marl over peat, peat over marl, all peat, and all marl; and, that the onset of marl accumulation is not limited to the 20th century but occurs at several intervals over the last 1700 years. The primary control on substrate type (marl vs. peat) may be local hydrologic and geomorphic features (sinkholes vs depressions) rather than changes in regional hydrology. Pollen evidence from most sites is consistent with our early study and indicates a regional shift to shorter hydroperiod conditions early in the 20th century that are tied to changes in water management. This study reflects the importance of relying on more than just a single core, or single transect of cores, for teasing apart the local and regional effects on peatlands.

The effect of wood ash fertilization on soil respiration and tree stand growth in boreal peatland forests

NASA Astrophysics Data System (ADS)

Liimatainen, Maarit; Maljanen, Marja; Hytönen, Jyrki

2017-04-01

Out of Finland's original 10 million hectares of peatlands over half has been drained for forestry. Natural peatlands act as a sink for carbon but when peatland is drained, increased oxygen concentration in the peat accelerates the aerobic decomposition of the old organic matter of the peat leading to carbon dioxide (CO2) emissions to atmosphere. Increasing use of bioenergy increases also the amount of ash produced as a byproduct in power plants. Wood ash contains all essential nutrients for trees to grow except nitrogen. Therefore, wood ash is ideal fertilizer for nitrogen rich peatland forests where lack of phosphorus or potassium may restrict tree growth. At the moment, wood ash is the only available PK-fertilizer for peatland forests in Finland and areas of peatland forests fertilized with ash are increasing annually. The effects of wood ash on vegetation, soil properties and tree growth are rather well known although most of the studies have been made using fine ash whereas nowadays mostly stabilized ash (e.g. granulated) is used. Transporting and spreading of stabilized ash is easier than that of dusty fine ash. Also, slower leaching rate of nutrients is environmentally beneficial and prolongs the fertilizer effect. The knowledge on the impact of granulated wood ash on greenhouse gas emissions is still very limited. The aim of this study was to examine the effects of granulated wood ash on CO2 emissions from peat and tree stand growth. Field measurements were done in two boreal peatland forests in 2011 and 2012. One of the sites is more nutrient rich with soil carbon to nitrogen ratio (C/N) of 18 whereas the other site is nutrient poor with C/N ratio of 82. Both sites were fertilized with granulated wood ash in 2003 (5000 kg ha-1). The effect of fertilization was followed with tree stand measurements conducted 0, 5 and 10 years after the fertilization. The CO2 emissions of the decomposing peat (heterotrophic respiration) were measured from study plots where vegetation and litter were removed to eliminate respiration by vegetation (autotrophic respiration). Roots were cut by installing aluminum tubes into the depth of 30 cm. Emissions were measured with chamber method using portable CO2 analyzer. Soil temperature was measured simultaneously with gas measurements manually from the depth of 5 cm as well as continuously with data loggers embedded into the peat. Annual soil respiration was modelled assuming that emissions change as a function of temperature. According to preliminary results, fertilization with granulated wood ash increased CO2 emissions of the peat significantly, especially in nutrient poor site. Ash fertilization increased also strongly the accumulation of carbon into the trees. Nonetheless, in both sites CO2emissions from decomposing peat where higher than carbon that was stored in biomass. This was the case especially in the nutrient poor site where trees are growing poorly and due to low peat nitrogen content the area is not considered suitable for ash fertilization. However, at the more fertile site both stand C sequestration and soil C efflux increased similarly.

SPRUCE Whole Ecosystem Warming (WEW) Peat Water Content and Temperature Profiles for Experimental Plot Cores Beginning June 2016

DOE Data Explorer

Gutknecht, J. [Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.; Kluber, L. A. [Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.; Hanson, P. J. [Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.; Schadt, C. W. [Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A.

2016-06-01

This data set provides the peat water content and peat temperature at time of sampling for peat cores collected before and during the SPRUCE Whole Ecosystem Warming (WEW) study. Cores for the current data set were collected during the following bulk peat sampling events: 13 June 2016 and 23 August 2016. Over time, this dataset will be updated with each new major bulk peat sampling event, and dates/methods will be updated accordingly.

Microbiological profile of selected mucks

NASA Astrophysics Data System (ADS)

Dąbek-Szreniawska, M.; Wyczółkowski, A. I.

2009-04-01

INTRODUCTION Matyka-Sarzynska and Sokolowska (2000) emphasize that peats and peat soils comprise large areas of Poland. The creation of soil begins when the formation of swamp has ended. Gawlik (2000) states that the degree of influence of the mucky process of organic soils on the differentiations of the conditions of growth and development of plants is mainly connected with the changes of moisture-retentive properties of mucks which constitute the material for these soils, and the loss of their wetting capacities. The above-mentioned changes, which usually occur gradually and show a clear connection with the extent of dehydration and, at times, with its duration, intensify significantly when the soils are under cultivation. The mucky process of peat soils leads to transformations of their physical, chemical and biological properties. The main ingredient of peat soils is organic substance. The substance is maintained inside them by the protective activity of water. The process of land improvement reduces the humidity of the environment, and that Intensifies the pace of the activity of soil microorganisms which cause the decay of organic substance. The decay takes place in the direction of two parallel processes: mineralization and humification. All groups of chemical substances constituting peat undergo mineralization. Special attention should be called to the mineralization of carbon and nitrogen compounds, which constitute a large percentage of theorganic substance of the peat organic mass. Okruszko (1976) has examined scientificbases of the classification of peat soils depending on the intensity of the muck process. The aim of this publication was to conduct a microbiological characteristic of selected mucky material. METHODS AND MATERIALS Soil samples used in the experiments were acquired from the Leczynsko-Wlodawski Lake Region, a large area of which constitutes a part of the Poleski National Park, which is covered to a large extent with high peat bogs. It was a mucky-peat soil with different degrees of muck process, described by Gawlik (2000) as MtI - first step of muck process, and MtII - second step of muck process. The numbers of selected groups of microorganisms were established using the cultivation method. The total number of microorganisms, zymogenic, aerobic and anaerobic microorganisms (Fred, Waksman 1928), oligotrophic microorganisms, the number of fungi (Parkinson 1982), ammonifiers (Parkinson et al 1971), nitrogen reducers and amolytic microorganisms (Pochon and Tardieux 1962), were determined. RESULTS The interpretation of the obtained results should take into consideration not only the characteristics of the studied objects, but also the characteristics of the methods used and of the examined microorganisms. As a result of the experiments that were carried out, significant differences of the numbers of the examined groups of microorganisms, depending on the degree of the muck process, have been observed. The number of the examined groups was significantly higher in the soil at the first step muck process than the second step of muck process. Amylolytic bacteria were an exception. Probably, during the muck process, ammonification, nitrification and nitrogen reduction process take place at the same time, which is indicated by the number of individual groups of examined microorganisms. CONCLUSIONS During the muck process, the number of microorganisms in the soil decreases. It can be presupposed that during the muck process, the basic process realized by microorganisms is the degradation of organic substance, using nitrates as oxidizers. Dąbek-Szreniawska M.: 1992 Results of microbiological analysis related to soil physical properties. Zesz. Probl. Post. Nauk Roln., 398, 1-6. Fred E.B., Waksman S.A.: 1928 Laboratory manual of general microbiology. Mc Graw-Hill Book Company, New York - London pp. 145. Gawlik J.: 2000 Division of differently silted peat formations into classes according to their state of secondary transformations. Acta Agrophysica, 26, 17-24. Maciak F.: 1985 MateriaŁ y do ćwiczeń z rekultywacji teren

Reduction of trichloroethylene and nitrate by zero-valent iron with peat.

PubMed

Min, Jee-Eun; Kim, Meejeong; Pardue, John H; Park, Jae-Woo

2008-02-01

The feasibility of using zero-valent iron (ZVI) and peat mixture as in situ barriers for contaminated sediments and groundwater was investigated. Trichloroethylene (TCE) and nitrate (NO(3)(-)), redox sensitive contaminants were reduced by ZVI and peat soil mixture under anaerobic condition. Peat was used to support the sorption of TCE, microbial activity for biodegradation of TCE and denitrification while TCE and nitrate were reduced by ZVI. Decreases in TCE concentrations were mainly due to ZVI, while peat supported denitrifying microbes and further affected the sorption of TCE. Due to the competition of electrons, nitrate reduction was inhibited by TCE, while TCE reduction was not affected by nitrate. From the results of peat and sterilized peat, it can be concluded that peat was involved in both dechlorination and denitrification but biological reduction of TCE was negligible compared to that of nitrate. The results from hydrogen and methane gas analyses confirmed that hydrogen utilization by microbes and methanogenic process had occurred in the ZVI-peat system. Even though effect of the peat on TCE reduction were quantitatively small, ZVI and peat contributed to the removal of TCE and nitrate independently. The 16S rRNA analysis revealed that viable bacterial diversity was narrow and the most frequently observed genera were Bacillus and Staphylococcus spp.

Microbial Activity in Peat Soil Treated With Ordinary Portland Cement (OPC) and Coal Ashes

NASA Astrophysics Data System (ADS)

Rahman, J. A.; Mohamed, R. M. S. R.; Al-Gheethi, A. A.

2018-04-01

Peat soil is a cumulative of decayed plant fragment which developed as a result of microbial activity. The microbes degrade the organic matter in the peat soils by the production of hydrolysis enzyme. The least decomposed peat, known as fibric peat has big particles and retain lots of water. This made peat having high moisture content, up to 1500 %. The most decomposed peat known as sapric peat having fines particles and less void ratio. The present study aimed to understand the effects of solidification process on the bacterial growth and cellulase (CMCase) enzyme activity. Two types of mixing were designed for fibric, hemic and sapric peats; (i) Ordinary Portland cement (OPC) at an equal amount of dry peat, with 25 % of fly ash (FA) and total of coarse particle, a combination of bottom ash and fibre of 22 – 34 %, (ii) fibric peat was using water-to-binder ratio (w/b) = 1, 50% OPC, 25 % bottom ash (BA) and 25 % FA. For hemic and sapric peat, w/b=3 with 50 % OPC and 50 % BA were used. All samples were prepared triplicates, and were cured for 7, 14, 28 and 56 days in a closed container at room temperature. The results revealed that the first mix design giving a continuous strength development. However, the second mix design shows a decreased in strength pattern after day 28. The influence of the environment factors such as alkaline pH, reduction of the water content and peat temperature has no significant on the reduction amount of native microbes in the peat. The microbes survived in the solidified peat but the amount of microbes were found reduced for all types of mixing Fibric Mixed 1 (FM1), Hemic Mixed 1(HM1) and Sapric Mixed 1 (SM1) were having good strength increment for about 330 – 1427 % with enzymatic activity recorded even after D56. Nevertheless, with increase in the strength development through curing days, the enzymatic activities were reduced. For the time being, it can be concluded that the microbes have the ability to adapt with new environment. The reactivity of the microbes relates with the strength of solidified peat.

Subsidence due to peat oxidation and impact on drainage infrastructures in a farmland catchment south of the Venice Lagoon

NASA Astrophysics Data System (ADS)

Gambolati, G.; Putti, M.; Teatini, P.; Gasparetto Stori, G.

2006-03-01

Large agricultural areas reclaimed in the past century, south of the Venice Lagoon, have experienced significant land subsidence due to oxidation of peat organic soils. This has exposed the region to flood hazard particularly during severe storms and has contributed to increase the marginal management cost of the infrastructures (ditches, levees, pumping stations) designed to operate the drainage system. Direct measurements and indirect evidence from the channel network suggest a land settlement between 1.5 and 2 m over the past 70 years. This paper provides an overview of the problem with important information on its most recent evolution.

Does Miscanthus cultivation on organic soils compensate for carbon loss from peat oxidation? A dual label study

NASA Astrophysics Data System (ADS)

Bader, Cédric; Leifeld, Jens; Müller, Moritz; Schulin, Rainer

2016-04-01

Agricultural use of organic soils requires drainage and thereby changes conditions in these soils from anoxic to oxic. As a consequence, organic carbon that had been accumulated over millennia is rapidly mineralized, so that these soils are converted from a CO2 sink to a source. The peat mineralization rate depends mainly on drainage depth, but also on crop type. Various studies show that Miscanthus, a C4 bioenergy plant, shows potential for carbon sequestration in mineral soils because of its high productivity, its dense root system, absence of tillage and high preharvest litterfall. If Miscanthus cropping would have a similar effect in organic soils, peat consumption and thus CO2 emissions might be reduced. For our study we compared two adjacent fields, on which organic soil is cultivated with Miscanthus (since 20 years) and perennial grass (since 6 years). Both sites are located in the Bernese Seeland, the largest former peatland area of Switzerland. To determine wether Miscanthus-derived carbon accumulated in the organic soil, we compared the stable carbon isotopic signatures of the experimental soil with those of an organic soil without any C4-plant cultivation history. To analyze the effect of C4-C accumulation on peat degradability we compared the CO2 emissions by incubating 90 soil samples of the two fields for more than one year. Additionally, we analysed the isotopic CO2 composition (13C, 14C) during the first 25 days of incubation after trapping the emitted CO2 in NaOH and precipitating it as BaCO3. The ∂13C values of the soil imply, that the highest share of C4-C of around 30% is situated at a depth of 10-20 cm. Corn that used to be cultivated on the grassland field before 2009 still accounts for 8% of SOC. O/C and H/C ratios of the peat samples indicate a stronger microbial imprint of organic matter under Miscanthus cultivation. The amount of CO2 emitted was not affected by the cultivation type. On average 57% of the CO2 was C4 derived in the Miscanthus field, whereas 38% was C4-derived in the Grassland field. According to our radiocarbon data, 38% of the CO2 must have originated from peat-derived OM on the Miscanthus field, whereas 57% of the CO2 was derived from peat in the grassland. Although peat minerlaization seems to be smaller and a significant amount of C4-C accumulated under Miscanthus, peat mineralization nonetheless contributed substantially to soil respiration. Together, our data do not support the hypothesis that Miscanthus cultivation can fully compensate for organic matter loss in drained peatlands.

Preliminary stable isotope results from the Mohos peat bog, East-Carpathians

NASA Astrophysics Data System (ADS)

Túri, Marianna; Palcsu, László; Futó, István; Hubay, Katalin; Molnár, Mihály; Rinyu, László; Braun, Mihály

2016-04-01

This work provides preliminary results of an isotope investigation carried out on a peat core drilled in the ombrotrophic Mohos peat bog, Ciomadul Mountain, (46°8'3.60"N, 25°54'19.43"E, 1050 m.a.s.l.), East Carpathians, Romania. The Ciomadul is a single dacitic volcano with two craters: the younger Saint Ana and the older Mohos which is a peat bog, and surrounded by a number of individual lava domes as well as a narrow volcaniclastic ring plain volcano. A 10 m long peat core has been taken previously, and is available for stable oxygen and carbon isotope analysis. It is known from our previous work (Hubay et al., 2015) that it covers a period from 11.500 cal year B.P. to present. The peat bog is composed mainly of Sphagnum, which has a direct relationship with the environment, making it suitable for examine the changes in the surrounding circumstances. Isotopic analysis of the prepared cellulose from Sphagnum moss has the attribute to provide such high resolution quantitative estimates of the past climate and there is no such climate studies in this area where the past climate investigations based on oxygen isotope analysis of the Sphagnum. Oxygen and carbon stable isotope analysis were carried out on the hemicellulose samples, which were chemically prepared for 14C dating and taken from every 30 cm of the 10 m long peat core. The oxygen isotope composition of the precipitation can be revealed from the δ18O values of the prepared cellulose samples, since, while carbon isotope ratio tells more about the wet and dry periods of the past. Studying both oxygen and carbon isotope signatures, slight fluctuations can be seen during the Holocene like some of the six periods of significant climate changes can be seen in this resolution during the time periods of 9000-8000, 6000-5000, 4200-3800, 3500-2500, 1200-1000, and 600-150 cal yr B.P. Additionally, the late Pleistocene - early Holocene environmental changes can be clearly observed as Pleistocene peat samples have increasingly negative delta values as going back in time. All measurements were carried out in Hertelendi Laboratory of Environmental Studies, Institute for Nuclear Research, Hungarian Academy of Sciences. Katalin Hubay, Mihály Braun, Sándor Harangi, László Palcsu, Marianna Túri, László Rinyu, Mihály Molnár, 2015. European Geosciences Union (EGU) General Assembly 2015, Radiocarbon dating of Sphagnum cellulose from Mohos peat bog, East Carpathians, accepted in CL5.10/GM1.10 Geophysical Research Abstracts Vol. 17, EGU2015-10813, 2015

Comparison of Shear Strength Properties for Undisturbed and Reconstituted Parit Nipah Peat, Johor

NASA Astrophysics Data System (ADS)

Azhar, A. T. S.; Norhaliza, W.; Ismail, B.; Abdullah, M. E.; Zakaria, M. N.

2016-11-01

Shear strength of soil is required to determine the soil stability and design the foundations. Peat is known as a soil with complex natural formations which also contributes problems to the researchers, developers, engineers and contractors in constructions and infrastructures. Most researchers conducted experiment and investigation of shear strength on peat using shear box test and simple shear test, but only a few had discovered the behavior of peat using triaxial consolidated undrained test. The aim of this paper is to determine the undrained shear strength properties of reconstituted peat and undisturbed peat of Parit Nipah, Johor for comparison purposes. All the reconstituted peat samples were formed with the size that passed opening sieve 3.35 mm and preconsolidation pressure at 100 kPa. The result of undrained shear strength of reconstituted peat was 21kPa for cohesion with the angle of friction, 41° compare to the undisturbed peat with cohesion 10 kPa and angle of friction, 16°. The undrained shear strength properties result obtained shows that the reconstituted peat has higher strength than undisturbed peat. For relationship deviator stress-strain, σd max and excess pore pressure, Δu, it shows that both of undisturbed and reconstituted gradually increased when σ’ increased, but at the end of the test, the values are slightly dropped. The physical properties of undisturbed and reconstituted peat were also investigated to correlate with the undrained shear strength results.

Investigation of occupational radiation exposures to NORM at an Irish peat-fired power station and potential use of peat fly ash by the construction industry.

PubMed

Organo, C; Lee, E M; Menezes, G; Finch, E C

2005-12-01

Annually, approximately 15% of Ireland's electricity requirement is provided through the combustion of 3 x 10(6) tonnes of peat. While the literature on coal-fired power generation is quite abundant, studies on the peat-fired power generation industry from a radiological point of view are scarce. A study of the largest Irish peat-fired power plant was initiated to review the potential occupational radiation exposures arising from the occurrence of naturally occurring radioactive material (NORM) at different stages of the industrial process and to investigate any radiological health consequences that may arise should peat fly ash be used as a component of building materials. Ambient gamma dose rate measurements, radon measurements, quantification of the occupational exposure from inhalation of airborne particles (personal air sampling) and gamma spectrometry analysis of peat, peat ash and effluent samples from the ash ponds were undertaken. The results indicate that the radiation dose received by any worker involved in the processing of the peat and the handling of the ash resulting from peat combustion does not exceed 150 microSv per annum. Regulatory control of the peat-fired power generation is therefore unnecessary according to the Irish legislation with regards to NORM. The potential use of peat fly ash as a by-product in the building industry was also found to have a negligible radiological impact for construction workers and for members of the public.

The legacy of wetland drainage on the remaining peat in the Sacramento-San Joaquin Delta, California, USA

USGS Publications Warehouse

Drexler, Judith Z.; Christian S. de Fontaine,; Steven J. Deverel,

2009-01-01

Throughout the world, many extensive wetlands, such as the Sacramento-San Joaquin Delta of California (hereafter, the Delta), have been drained for agriculture, resulting in land-surface subsidence of peat soils. The purpose of this project was to study the in situ effects of wetland drainage on the remaining peat in the Delta. Peat cores were retrieved from four drained, farmed islands and four relatively undisturbed, marsh islands. Core samples were analyzed for bulk density and percent organic carbon. Macrofossils in the peat were dated using radiocarbon age determination. The peat from the farmed islands is highly distinct from marsh island peat. Bulk density of peat from the farmed islands is generally greater than that of the marsh islands at a given organic carbon content. On the farmed islands, increased bulk density, which is an indication of compaction, decreases with depth within the unoxidized peat zone, whereas, on the marsh islands, bulk density is generally constant with depth except near the surface. Approximately 55–80% of the original peat layer on the farmed islands has been lost due to landsurface subsidence. For the center regions of the farmed islands, this translates into an estimated loss of between 2900-5700 metric tons of organic carbon/hectare. Most of the intact peat just below the currently farmed soil layer is over 4000 years old. Peat loss will continue as long as the artificial water table on the farmed islands is held below the land surface.

Zebrafish Locomotor Responses Predict Irritant Potential of ...

EPA Pesticide Factsheets

Over the past few decades, the drying and warming trends of global climate change have increased wildland fire (WF) season length, as well as geographic area impacted. Consequently, exposures to WF fine particulate matter (PM2.5; aerodynamic diameter <2.5 µm) are likely to increase in frequency and duration, contributing to a growing public health burden. Given the influence of fuel type and combustion conditions on WFPM2.5 composition, there is pressing need to identify the biomass fuel sources and emission constituents that drive toxicity. Previously, we reported the utility of 6-day post-fertilization (dpf) zebrafish larvae in evaluating diesel exhaust PM-induced irritation, demonstrating responses analogous to those in mammals. In the present study, combustions, separated by smoldering or flaming conditions, of pine needles, red oak, pine, eucalyptus, and peat were achieved using an automated tube furnace paired with a cryo-trapping apparatus to collect condensates of emissions. The condensates were extracted and prepared for use in zebrafish assays. We hypothesized that 1) the extractable organic fractions of biomass smoke PM will elicit dose-dependent irritant responses in 6-dpf zebrafish larvae, and 2) the relative potencies will vary across biomass emissions, potentially driven by varying chemical composition of fuel sources. Six-dpf zebrafish (n= 28-32/group) were exposed acutely to PM extracts (5 concentrations; 0.3-30 µg/ml; half-log intervals) and

Removal of metal(oid)s from contaminated water using iron-coated peat sorbent.

PubMed

Kasiuliene, Alfreda; Carabante, Ivan; Bhattacharya, Prosun; Caporale, Antonio Giandonato; Adamo, Paola; Kumpiene, Jurate

2018-05-01

This study aimed at combining iron and peat to produce a sorbent suitable for a simultaneous removal of cations and anions from a solution. Peat powder, an industrial residue, was coated with iron by immersing peat into iron salt solutions. The adsorption efficiency of the newly produced sorbent towards As, Cr, Cu and Zn was tested by means of batch adsorption experiments at a constant pH value of 5. Coating of Fe on peat significantly increased the adsorption of As (from <5% to 80%) and Cr (from <3% to 25%) in comparison to uncoated peat. Removal of cations on coated peat slightly decreased (by 10-15%), yet remained within acceptable range. Electron Microscopy combined with X-Ray Energy Dispersive Spectroscopy revealed that iron coating on the peat was rather homogenous and As and Cr were abundantly adsorbed on the surface. By contrast, Cu and Zn displayed a sparing distribution on the surface of the iron coated peat. These results indicate that iron-peat simultaneously target sufficient amounts of both cations and anions and can be used for a one-step treatment of contaminated groundwater. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Relationship between peat geochemistry and depositional environments, Cranberry Island, Maine

USGS Publications Warehouse

Raymond, R.; Cameron, C.C.; Cohen, A.D.

1987-01-01

The Heath, Great Cranberry Island, Maine, offers a unique locality for studying lateral and vertical relationships between radically different peat types within 1 km2. The majority of The Heath is a Sphagnum moss-dominated raised bog. Surrounding the raised bog is a swamp/marsh complex containing grass, sedge, Sphagnum moss, alder, tamarack, and skunk cabbage. Swamp/ marsh-deposited peat occurs both around the margins of The Heath and under Sphagnum-dominated peat, which was deposited within the raised bog. A third peat type, dominated by herbaceous aquatics, is present underlying the swamp/marsh-dominated peat but is not present as a dominant botanical community of The Heath. The three peat types have major differences in petrographic characteristics, ash contents, and associated minerals. Sulfur contents range from a low of 0.19 wt.% (dry) within the raised bog to a high of 4.44 wt% (dry) near the west end of The Heath, where swamp/marsh peat occurring directly behind a storm beach berm has been influenced by marine waters. The presence of major geochemical variations within a 1-km2 peat deposit suggests the need for in-depth characterization of potential peat resources prior to use. ?? 1987.

Antimony in recent, ombrotrophic peat from Switzerland and Scotland: Comparison with natural background values (5,320 to 8,020 14C yr BP) and implications for the global atmospheric Sb cycle

NASA Astrophysics Data System (ADS)

Shotyk, William; Krachler, Michael; Chen, Bin

2004-03-01

The lowest concentrations, atmospheric fluxes, and enrichments of Sb in a Swiss bog were found in peat samples dating from 8,020 to 5,320 14C yr BP when Sb inputs were proportional to those of Sc and effectively controlled by deposition of soil dust. For comparison with these ancient samples, modern peat samples from five rural areas of Switzerland and two remote areas of Scotland and Shetland are highly contaminated with Sb, with enrichments of the order of 30 to 80 times. "Lithogenic" Sb concentrations calculated using the Sc concentrations and background Sb/Sc ratio are dwarfed at all sites by "anthropogenic" Sb. The chronology and intensity of the Sb enrichments are in many ways similar to those of Pb which indicates that (1) Sb, like Pb, is well preserved in ombrotrophic peat and (2) the extent of human impacts on the geochemical cycle of Sb is comparable to that of Pb. The similar distribution of Sb and Pb can be explained in terms of their chemical and mineralogical associations, with most lead minerals being rich in Sb. Assuming that the "background" Sb flux (0.35 μg/m2/yr) from the Swiss bog is representative of preanthropogenic deposition rates worldwide, the global flux of natural Sb is estimated at 154 T/a. Using the natural Pb flux published by [1987] of 2600 T/a and the "background" Pb/Sb ratio (29) of the preanthropogenic peat samples, the global flux of natural Sb is estimated at 90 T/a. Either way, these values (90 to 154 T/a) are considerably lower than the current estimate of natural Sb to the global atmosphere (2400 T/a) published by [2001]. Assuming that the current estimate of anthropogenic Sb to the global atmosphere (1600 T/a) is correct [, 2001], the ratio of anthropogenic to natural Sb emissions is on the order of 10 to 18. Taken together, the data from modern and ancient peat samples suggests that the impact of human activities on the global geochemical cycle of Sb may have been underestimated by an order of magnitude. Like Pb, Sb has no known biological function, has a similar toxicity, and is a cumulative poison. The environmental geochemistry of Sb therefore may have a relevance to human and environmental health comparable to that of Pb.

Substrate quality and nutrient availability influence CO2 production from tropical peat decomposition

NASA Astrophysics Data System (ADS)

Swails, E.; Jaye, D.; Verchot, L. V.; Hergoualc'h, K.; Wahyuni, N. S.; Borchard, N.; Lawrence, D.

2015-12-01

In Indonesia, peatlands are a major and growing source of greenhouse gas emissions due to increasing pressure from oil palm and pulp wood plantations. We are using a combination of field measures, laboratory experiments, and remote sensing to investigate relationships among land use, climatic factors and biogeochemical controls, and their influence on trace gas fluxes from tropical peat soils. Analysis of soils collected from peat sites on two major islands indicated substantial variation in peat substrate quality and nutrient content among land uses and geographic location. We conducted laboratory incubations to test the influence of substrate quality and nutrient availability on CO2 production from peat decomposition. Differences in peat characteristics attributable to land use change were tested by comparison of forest and oil palm peat samples collected from the same peat dome in Kalimantan. Regional differences in peat characteristics were tested by comparison of samples from Sumatra with samples from Kalimantan. We conducted additional experiments to test the influence of N and P availability and labile carbon on CO2 production. Under moisture conditions typical of oil palm plantations, CO2 production was higher from peat forest samples than from oil palm samples. CO2 production from Sumatra and Kalimantan oil palm samples was not different, despite apparent differences in nutrient content of these soils. N and P treatments representative of fertilizer application rates raised CO2 production from forest samples but not oil palm samples. Labile carbon treatments raised CO2 production in all samples. Our results suggest that decomposition of peat forest soils is nutrient limited, while substrate quality controls decomposition of oil palm soils post-conversion. Though fertilizer application could accelerate peat decomposition initially, fertilizer application may not influence long-term CO2 emissions from oil palm on peat.

Biofiltration using peat and a nutritional synthetic packing material: influence of the packing configuration on H2S removal.

PubMed

Dumont, Eric; Cabral, Flavia Da Silva; Le Cloirec, Pierre; Andrès, Yves

2013-01-01

This study aims to evaluate the feasibility of using a nutritional synthetic material (UP20) combined with fibrous peat as a packing material in treating H2S (up to 280 ppmv). Three identical laboratory-scale biofilters with different packing material configurations (peat only; peat + UP20 in a mixture; peat + UP20 in two layers) were used to determine the biofilter performances. The superficial velocity of the polluted gas on each biofilter was 65 m/h (gas flow rate 0.5 Nm3 /h) corresponding to an empty bed residence time = 57 s. Variations in elimination capacity, removal efficiency, temperature and pH were tracked during 111 d. A removal efficiency of 100% was obtained for loading rates up to 6 g/m3/h for the biofilter filled with 100% peat, and up to 10 g/m3/h for both biofilters using peat complemented with UP20. For higher loading rates (up to 25.5 g/m3/h), the configuration ofpeat-UP20 in a mixture provided the best removal efficiencies (around 80% compared to 65% for the configuration of peat-UP20 in two layers and 60% for peat only). Microbial characterization highlighted that peat is able to provide sulfide-oxidizing bacteria. Through kinetic analysis (Ottengrafand Michaelis-Menten models were applied), it appeared that the configuration peat-UP20 in two layers (80/20 v/v) did not show significant improvement compared with peat alone. Although the configuration of peat-UP20 in a mixture (80/20 v/v) offered a real advantage in improving H2S treatment, it was shown that this benefit was related to the bed configuration rather than the nutritional properties of UP20.

A Study on Factors Affecting Strength of Solidified Peat through XRD and FESEM Analysis

NASA Astrophysics Data System (ADS)

Rahman, J. A.; Napia, A. M. A.; Nazri, M. A. A.; Mohamed, R. M. S. R.; Al-Geethi, A. S.

2018-04-01

Peat is soft soil that often causes multiple problems to construction. Peat has low shear strength and high deformation characteristics. Thus, peat soil needs to be stabilized or treated. Study on peat stabilization has been conducted for decades with various admixtures and mixing formulations. This project intends to provide an overview of the solidification of peat soil and the factors that affecting the strength of solidified peat soil. Three types of peats which are fabric, hemic and sapric were used in this study to understand the differences on the effect. The understanding of the factors affecting strength of solidified peat in this study is limited to XRD and FESEM analysis only. Peat samples were collected at Pontian, Johor and Parit Raja, Johor. Peat soil was solidified using fly ash, bottom ash and Portland cement with two mixing formulation following literature review. The solidified peat were cured for 7 days, 14 days, 28 days and 56 days. All samples were tested using Unconfined Compressive Strength Test (UCS), X-ray diffraction (XRD) and Field Emission Scanning Electron Microscope (FESEM). The compressive strength test of solidified peat had shown consistently increase of sheer strength, qu for Mixing 1 while decrease of its compressive strength value for Mixing 2. All samples were tested and compared for each curing days. Through XRD, it is found that all solidified peat are dominated with pargasite and richterite. The highest qu is Fabric Mixing 1(FM1) with the value of 105.94 kPa. This sample were proven contain pargasite. Samples with high qu were observed to be having fly ash and bottom ash bound together with the help of pargasite. Sample with decreasing strength showed less amount of pargasite in it. In can be concluded that XRD and FESEM findings are in line with UCS values.

Preliminary investigation of the formation age and chemical characterization of the tropical peat in the middle Sepik Plain, northern Papua New Guinea

NASA Astrophysics Data System (ADS)

Ono, Eisuke; Umemura, Mitsutoshi; Ishida, Takuya; Takenaka, Chisato

2015-12-01

Seven gouge cores in the middle Sepik Plain (northern Papua New Guinea) were bored to clarify the depositional age and the chemical characteristics of the tropical peat. The weakly-acidic peat layer (3-4 m thick) is distributed around the south bank of the Blackwater Lakes. The peat layer consists mainly of sago palm and grass remains within a mineral matrix of very fine sand and clay. Radiocarbon dating indicates that the peat's formation had commenced by 3,710-3,560 cal BP. Nitrogen and exchangeable potassium reach their highest values in the upper 60 cm of the peat column. Conversely, exchangeable sodium, calcium and magnesium, as well as carbon, increase their values with depth in the peat. These differences in the exchangeable cations' contribution suggest changes in the plant species, which were decomposed during the peat's formation.

Late-Holocene environmental and climatic changes in central part of the Western Sayan Mountain

NASA Astrophysics Data System (ADS)

Grenaderova, Anna; Sharafutdinov, Ruslan

2016-04-01

The purpose of this collaborative research is to determine how Holocene climate variability affects the landscapes evolution in valley of Buyba River. The work was conducted at the intersection of three disciplines: paleobotany, mineralogy and geochemistry. Data about environmental and climate changes in the Late Holocene in central part of Western Sayan are presented. We analyzed four peatland locations that, related to a single area of the river catchment. Sediment cores were taken from the central part of the peatland landscape. The age was determined by radiocarbon dating. Start of bog forming occurred asynchronously within the northern macroslope of Western Sayan. Bogs age decreases with the increase in the absolute elevations. On the highest elevation of 1656 m, the process of peat accumulation started 460 ± 80 years ago, after a significant reduction of snowfields. The most ancient peat layers formed at the altitude of 1320 meters and in elevations down the slope, and were aged 2950 ± 110 years or more (up to 5000 years). Over the period from 5000 to 4000 years ago, there were dryer and warmer climate conditions in the research area. Slopes of trough valleys were covered with sub-alpine shrubs of dwarf birch and alder, tree layer was absent. According to the pollen analysis, the role of tree vegetation (Pinus forest with participation of Pinus sibirica and Betula sect. Albae) was larger at the foothills. At the same time, at an altitude of 1650 m peat deposits are not formed, only isolated remains of plant detritus were found in much younger gravelly-clay sediments. Shallow flowing pond conditions were characteristic for stages before peat accumulation . Geochemical analysis of the ratio Th / U in loam, underlying peat, allows one to infer about oxidizing conditions during sedimentation. Analysis of the minerals in the peat layer, and the dynamics of accumulation of Na, Al, Ti (INAA-method) indicate that the time interval 500-2200 years was characterized with most stable hydrological conditions. During this period, the flood waters have supplied the least amount of allochthonous contaminants on the surface of the swamp. On the peatlands, sedge and sedge-moss plant communities were developed. Main plant species which grows in the peatlands are Carex altaica (Gorodk.) V.Krecz, Carex limosa L. Tomentypnum nitens Hedw., Aulacomnium palustre (Hedw.) Schwaegr., Warnstorfia exannulata (B.S.G.) Loeske., Thelypteris palustris Schott, Baeothryon caespitosum (L.) A.Dietr. During the last 500 years an increase of allochthonous contaminants inputs to marsh sediments is observed. In our opinion, the main causes of the increase were reduction the forest area, sharper contrast of summer and winter temperatures and more rapid melting of snow in early summer. The last cause lead to increased levels of floods. Eutrophic-mesotrophic sphagnum communities (Sphagnum warnstorfii Russ., Sph.subsecundum Nees,, Sphagnum angustifolium Jensen., Sph. fuscum (Schimp.) Klinggr.), which are growing at the moment, begin to develop in the peatlands since 500 years ago.

Ditch network maintenance in peat-dominated boreal forests: Review and analysis of water quality management options.

PubMed

Nieminen, Mika; Piirainen, Sirpa; Sikström, Ulf; Löfgren, Stefan; Marttila, Hannu; Sarkkola, Sakari; Laurén, Ari; Finér, Leena

2018-03-27

The objective of this study was to evaluate the potential of different water management options to mitigate sediment and nutrient exports from ditch network maintenance (DNM) areas in boreal peatland forests. Available literature was reviewed, past data reanalyzed, effects of drainage intensity modeled, and major research gaps identified. The results indicate that excess downstream loads may be difficult to prevent. Water protection structures constructed to capture eroded matter are either inefficient (sedimentation ponds) or difficult to apply (wetland buffers). It may be more efficient to decrease erosion, either by limiting peak water velocity (dam structures) or by adjusting ditch depth and spacing to enable satisfactory drainage without exposing the mineral soil below peat. Future research should be directed towards the effects of ditch breaks and adjusted ditch depth and spacing in managing water quality in DNM areas.

The legacy of wetland drainage on the remaining peat in the Sacramento San Joaquin Delta, California, USA

USGS Publications Warehouse

Drexler, J.Z.; De Fontaine, C. S.; Deverel, S.J.

2009-01-01

Throughout the world, many extensive wetlands, such as the Sacramento-San Joaquin Delta of California (hereafter, the Delta), have been drained for agriculture, resulting in land-surface subsidence of peat soils. The purpose of this project was to study the in situ effects of wetland drainage on the remaining peat in the Delta. Peat cores were retrieved from four drained, farmed islands and four relatively undisturbed, marsh islands. Core samples were analyzed for bulk density and percent organic carbon. Macrofossils in the peat were dated using radiocarbon age determination. The peat from the farmed islands is highly distinct from marsh island peat. Bulk density of peat from the farmed islands is generally greater than that of the marsh islands at a given organic carbon content. On the farmed islands, increased bulk density, which is an indication of compaction, decreases with depth within the unoxidized peat zone, whereas, on the marsh islands, bulk density is generally constant with depth except near the surface. Approximately 5580 of the original peat layer on the farmed islands has been lost due to land-surface subsidence. For the center regions of the farmed islands, this translates into an estimated loss of between 29005700 metric tons of organic carbon/hectare. Most of the intact peat just below the currently farmed soil layer is over 4000 years old. Peat loss will continue as long as the artificial water table on the farmed islands is held below the land surface. ?? 2009 The Society of Wetland Scientists.

Spatial-temporal controls on peatland carbon dynamics in the Hudson Bay Lowland, Canada: Reducing landscape-scale uncertainty in a changing climate

NASA Astrophysics Data System (ADS)

Packalen, M. S.; Finkelstein, S. A.; McLaughlin, J.

2015-12-01

Global peatlands currently store more than 650 Pg of carbon (C) that has accumulated over millennia, and contributed to a net climatic cooling. However, controls on spatial-temporal C dynamics may differ regionally. With at least 30 Pg C sequestered in the Hudson Bay Lowlands Canada (HBL), the vulnerability of this globally significant peat C reservoir remains uncertain under conditions of a changing climate and enhanced anthropogenic pressure. Here, we synthesize our current understanding of controls on C dynamics in the HBL using detailed peat records. Our data reveal that widespread bog-fen patterning across the HBL is related to the distribution of peat C in space and time, indicating that topographic and ecohydroclimatic controls are potentially important determinants of C mass accretion. We find that while peat age is closely related to timing of land emergence and peat depth in the HBL, considerable variation in the total C mass among sites of similar peat age suggests that additional factors may further explain trends in peat C dynamics. Among these factors, we find that temperature, precipitation, and potential evapotranspiration in the HBL account for up to half of the variation in the distribution of the peat C mass, whereby regions with warmer and wetter conditions support larger peat C masses. Moreover, we find that the rate of C accumulation is greatest for young fen peatlands developing during warmer mid-Holocene climates; but that long-term C stores are greatest in association with bog peatlands. Although nearly two-thirds of HBL peat C is of late Holocene age, most of the reconstructed potential C losses also occurred during the late Holocene, as previously accrued peat decayed. Our findings support the hypothesis that both climate and ecohydrological factors are important drivers of peat C dynamics in the HBL, alongside geophysical controls on the timing of peat initiation. As the HBL peat complex continues to rapidly expand, it may remain a globally significant C reservoir. However, conservative climate scenarios predict warmer and wetter conditions in the next century, beyond the range of past climate variability. Ongoing elucidation of controls on peat C dynamics may further inform our understanding of the response of the HBL peat C reservoir to future climate and resource management scenarios.

The wettability of selected organic soils in Poland

NASA Astrophysics Data System (ADS)

Całka, A.; Hajnos, M.

2009-04-01

The wettability was measured in the laboratory by means of two methods: Water Drop Penetration Time (WDPT) test and Thin Column Wicking (TCW) method. WDPT is fast and simple method and was used to investigate potential water repellency of analyzed samples. TCW is an indirect method and was used to determine contact angles and surface free energy components. The measurement was performed in horizontal teflon chambers for thin-layer chromatography, adapted for tubes 10 cm long. The experiment was carried out on muck soils (samples were taken from two levels of soil profile: 0-20 cm and 20-40 cm) and peat soils. There were two types of peats: low-moor peats and high moor peats. Samples of low-moor peats were taken from level 25-75 cm (alder peat) and 75-125cm (sedge peat) and 25-75 cm (peloid peat). Samples of high moor peats from level 25-175 cm (sphagnum peat) and 175-225 cm (sphagnum peat with Eriophorum). There was found no variability in persistence of potential water repellency but there were differences in values of contact angles of individual soil samples. Both muck and peat samples are extremely water repellent soils. Water droplets persisted on the surface of soils for more than 24 hours. Contact angles and surface free energy components for all samples were differentiated. Ranges of water contact angles for organic soils are from 27,54o to 96,50o. The highest values of contact angles were for sphagnum peats, and the lowest for muck soil from 20-40 cm level. It means, that there are differences in wettability between these samples. Muck soil is the best wettable and sphagnum peats is the worst wettable soil. If the content of organic compounds in the soil exceeds 40% (like in peats), the tested material displays only dispersion-type interactions. Therefore for peat soils, the technique of thin column wicking could only be used to determine the dispersive component γiLW. For muck soils it was also determined electron-acceptor (Lewis acid) γ+ and electron-donor (Lewis base) γ- surface free energy components. The authors gratefully acknowledge the Ministry of Science and Higher Education for financial support of this work (grant No. N N310 149335).

Methodology for producing 100 tons of fuel peat for a cement plant test burn. Metodologia para producir 100 toneladas de turba combustible para una prueba de quema en uns planta de cemento (in English; Spanish)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen, A.B.; Malavassi, L.; Ramirez, O.

1989-05-01

As a part of the Agency for International Development-funded cooperative project between Los Alamos and Costa Rica, the burning characteristics of Costa Rican peat were to be tested in an application. The cement plant owned by Industria National de Cemento in Cartago has a capability to handle solid fuel and was chosen for the burn demonstration. The Jungle No. 1 Peat Deposit near El Cairo was chosen as the site of the peat excavation. This peat production methodology study covers project site selection, installation of an access road and clearing of the jungle vegetation, removal of an upper layer ofmore » organic peat, excavation of fuel-grade peat, transport of the peat to the drying site, and drying and stockpiling of the finished product. As of this date the peat removal for the demonstration project has been started, and a description of the operation is included as an appendix to this paper. 10 figs.« less

Development of new index for forest fire risk using satellite images in Indonesia through the direct spectral measurements of soil

NASA Astrophysics Data System (ADS)

Hashimoto, A.; Akita, M.; Takahashi, Y.; Suzuki, H.; Hasegawa, Y.; Ogino, Y.; Naruse, N.; Takahashi, Y.

2016-12-01

In recent years, the smoke caused by the forest fires in Indonesia has become a serious problem. Most of the land in Indonesia is covered with peat moss, which occurs the expanding of fires due to the burning itself. Thus, the surface soil water, reflecting the amount of precipitation in the area, can become the indication of the risk of fires. This study aims to develop a new index reflecting the risk of forest fires in Indonesia using satellite remote sensing through the direct spectral measurements of peat moss soil.We have prepared the peat moss in 7 steps of soil water content measured at an accuracy of ±15 percent (Field pro, WD-3). We obtained spectra between 400nm and 1050nm (Source: halogen lamp, spectroscope: self-made space time, spectral analysis kit) from the peat moss.The obtained spectra show the difference from the previous spectral measurement for the soil in various water content. There are the features, especially, in the wavelength range of ultraviolet (400-450nm) and infrared (530-800nm) as shown in the figure; the more the soil water increases, the lower the reflectance becomes. We have developed a new index using the New deep blue band (433 453nm and NIR band 845 885nm of Landsat 8. The resulting satellite images calculated by our original index appears to reflect the risk of forest fires rather than well-known indices such as Normalized Difference Water Index and Normalized difference Soil Index.In conclusion, we have created a new index that highly reflects to the degree of soil water of a peat soil in Indonesia.

Peat

USGS Publications Warehouse

Jasinski, S.M.

2006-01-01

In 2005, peat was harvested in 15 US states. Florida, Michigan and Minnesota accounted for more than 80% of the US production. Reed-sedge was the dominant variety of peat harvested in the United States. More than 56% of all peat used in the US was imported from Canada. With the growing interest in gardening, landscaping related to home construction and golf courses, peat usage is expected to remain near current levels during the next several years.

Influence of peat formation conditions on the transformation of peat deposit organic matter

NASA Astrophysics Data System (ADS)

Serebrennikova, O. V.; Strelnikova, E. B.; Preis, Yu I.; Duchko, M. A.

2015-11-01

The paper studies the individual composition of n-alkanes, polycycloaromatic hydrocarbons, steroids, bi-, tri-, and pentacyclic terpenoids of two peat deposits of rich fen Kirek located in Western Siberia. Considering the individual n-alkanes concentrations, some indexes were calculated to estimate the humidity during peat formation. It was shown that the pH of peat medium primarily affects steroids, tri- and pentacyclic terpenoids transformations.

Content of radionuclides in the peat deposit of swamps

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nifontova, M.G.; Makovskii, V.I.

1995-11-01

The results are given of comparative analysis of the content and transformation of {sup 90}Sr and {sup 137}Cs over a peat deposit of swamps. During radioecological study, account was taken of the quantitative composition and physicochemical properties of the peat, as well as of the specific nature of the entry of radioactive products to peat deposits. Considering the increased capacity of peat for accumulating radionuclides and the specific features of sorption processes in a peat deposit, it is expedient to utilize swamps as a convenient natural object for continuous monitoring of radioactive contamination of the environment.

Micropetrographic characteristics of peats from modern coal-forming environments in Okefenokee Swamp, Georgia and Albemarle-Pamlico Peninsular Swamps, North Carolina

DOE Office of Scientific and Technical Information (OSTI.GOV)

Corvinus, D.A.

1982-01-01

The Okefenokee Swamp, over 400,000 acres, is a swamp-marsh complex dominated by Taxodium-swamp vegetaion on its west side and Nymphaea-marsh vegetation onits east side. The Albemarle-Pamlico Peninsular Swamps primarily support a pocosin-bay vegetation. The Taxodium-dominated peats of the Okefenokee are more similar botanically to the Albemarle-Pamlico bay peats than are the Okefenokee Nymphaea-dominated peats. Some petrographic characteristics are common to all three peat types. The majority of cell walls in the peat exhibit colors (yellow to orange to red) which they did not display in their living state. This is believed to be from impregnation by the various cell fillingsmore » present in the peats. Unoxidized fragmented (granular) material in all three peat types usually occurs in larger amounts than oxidized (darkened) material. In Taxodium-dominated and bay peats the fragmented matrix is also usually more prevalent than the preserved material (intact cell walls and cell fillings). On the other hand, preserved material is most common in Nymphaea-dominated peats. It is believed that the majority of fragmented material is derived from the surface litter and that swamp vegetation contributes more surface litter than does marsh vegetation.« less

Soils of the Southwestern Part of the Pacific Coast of Russia

NASA Astrophysics Data System (ADS)

Kostenkov, N. M.; Zharikova, E. A.

2018-02-01

The diversity of soils in the southwestern part of the Pacific coast of Russia (Primorie region) is discussed. Overall, 17 soil types belonging to 8 soil orders have been described in this region, and their morphology and properties have been studied. The diversity of plant communities, geomorphic conditions, and parent materials and relatively mild (as compared with other parts of the Far East region of Russia) specify the great variability of soil cover patterns. Low sea terraces are occupied by various peat, organo-accumulative, and gley soils; poorly drained medium-high terraces are the areas of various dark-humus and darkhumus gleyed soils. Typical and gleyic dark-humus podbels, dark-humus, and dark-humus gleyed soils formed on the high sea terraces. Residual elevations are occupied by brown forest (burozemic) soils, including typical burozems, dark-humus burozems, and gleyic dark-humus burozems and by dark-humus podbels. Various alluvial, gleyic gray-humus, and mucky gley soils are developed on riverine plains. On general, darkhumus soils with the high (>10%) humus content predominate; the area of dark-humus podbels us estimated at about 20%, and the area of dark-humus burozems is about 12%. All the soils in this region are specified by increased acidity values. The exchangeable sodium content is often high in the upper soil horizons with maximum values (0.71-1.19 cmol(c)/kg) in the peat gleyzems, peaty dark-humus soils, mucky-gley soils, and eutrophic peat soils of sea terraces. The grouping of the soils with respect to their physicochemical and agrochemical properties is suggested.

How temporal patterns in rainfall determine the geomorphology and carbon fluxes of tropical peatlands.

PubMed

Cobb, Alexander R; Hoyt, Alison M; Gandois, Laure; Eri, Jangarun; Dommain, René; Abu Salim, Kamariah; Kai, Fuu Ming; Haji Su'ut, Nur Salihah; Harvey, Charles F

2017-06-27

Tropical peatlands now emit hundreds of megatons of carbon dioxide per year because of human disruption of the feedbacks that link peat accumulation and groundwater hydrology. However, no quantitative theory has existed for how patterns of carbon storage and release accompanying growth and subsidence of tropical peatlands are affected by climate and disturbance. Using comprehensive data from a pristine peatland in Brunei Darussalam, we show how rainfall and groundwater flow determine a shape parameter (the Laplacian of the peat surface elevation) that specifies, under a given rainfall regime, the ultimate, stable morphology, and hence carbon storage, of a tropical peatland within a network of rivers or canals. We find that peatlands reach their ultimate shape first at the edges of peat domes where they are bounded by rivers, so that the rate of carbon uptake accompanying their growth is proportional to the area of the still-growing dome interior. We use this model to study how tropical peatland carbon storage and fluxes are controlled by changes in climate, sea level, and drainage networks. We find that fluctuations in net precipitation on timescales from hours to years can reduce long-term peat accumulation. Our mathematical and numerical models can be used to predict long-term effects of changes in temporal rainfall patterns and drainage networks on tropical peatland geomorphology and carbon storage.

How temporal patterns in rainfall determine the geomorphology and carbon fluxes of tropical peatlands

PubMed Central

Hoyt, Alison M.; Gandois, Laure; Eri, Jangarun; Dommain, René; Abu Salim, Kamariah; Kai, Fuu Ming; Haji Su’ut, Nur Salihah; Harvey, Charles F.

2017-01-01

Tropical peatlands now emit hundreds of megatons of carbon dioxide per year because of human disruption of the feedbacks that link peat accumulation and groundwater hydrology. However, no quantitative theory has existed for how patterns of carbon storage and release accompanying growth and subsidence of tropical peatlands are affected by climate and disturbance. Using comprehensive data from a pristine peatland in Brunei Darussalam, we show how rainfall and groundwater flow determine a shape parameter (the Laplacian of the peat surface elevation) that specifies, under a given rainfall regime, the ultimate, stable morphology, and hence carbon storage, of a tropical peatland within a network of rivers or canals. We find that peatlands reach their ultimate shape first at the edges of peat domes where they are bounded by rivers, so that the rate of carbon uptake accompanying their growth is proportional to the area of the still-growing dome interior. We use this model to study how tropical peatland carbon storage and fluxes are controlled by changes in climate, sea level, and drainage networks. We find that fluctuations in net precipitation on timescales from hours to years can reduce long-term peat accumulation. Our mathematical and numerical models can be used to predict long-term effects of changes in temporal rainfall patterns and drainage networks on tropical peatland geomorphology and carbon storage. PMID:28607068

Reconstruction of postglacial landscape evolution within the eastern periphery of Chuya depression on the basis of multidisciplinary analysis of peats in Boguty river basin, SE Altai, Russia

NASA Astrophysics Data System (ADS)

Agatova, A. R.; Khazina, I. V.; Bronnikova, M. A.; Uspenskaya, O. N.; Nepop, R. K.

2018-03-01

This paper presents the results of multidisciplinary investigations of the peat-bed under hummocky permafrosted boggy meadow within the Boguty basin. For the last 7600 years 4 evolutionary phases of peatbog formation within the drained part of Low Boguty Lake bottom were established and corresponding 4 pollen complexes were described. 18 radiocarbon dates suggest some chronological bench marks of postglacial landscape evolution in the region. After degradation of Sartan glaciation about 14000 BP, trees grew in now forestless areas at 11000 BP and 8500-7800 BP. The climate in the first half of the Holocene was warmer and more humid. Accumulation of lacustrine loams within the studied peatbog occurred before 7600 BP with predominated algae Pediastrum, Zygnemataceae and Botryococcus. After the lake level lowered in the result of destructing moraine dam, two lower peat horizons were developed about 7600 – 7200 BP. An episode of significant lake desiccation (later than 7200 BP) was recorded in all proxy archives. Further rise of water supply led to increasing the number of water-bog plants, diatomaceous, euglenic and green algae. At the same time, the pollen of xerophytes began to predominate in the pollen complexes, indicating aridization. The final stage reflects stable peatbog drying and its transformation into boggy meadow, decomposition and mineralization of peat.

The roles of weather modification technology in mitigation of the peat fires during a period of dry season in Bengkalis, Indonesia

NASA Astrophysics Data System (ADS)

Sandhyavitri, A.; Perdana, M. A.; Sutikno, S.; Widodo, F. H.

2018-02-01

The annual peat fire disasters have suffered human life, deteriorated peat land ecosystems, and caused severe economic losses in Indonesia, Malaysia, Brunei, and Singapore during a period of 2014-2016. The objective of this study is to investigate to what extent the weather modification technology (WMT) may play its roles in increasing the precipitation rates in order to mitigate the peat fires disaster in Bengkalis, Riau Province, Indonesia. The study obtained the precipitation rates data from the tropical rainfall measuring mission (TRMM) satellite during the period of 2014, 2015 and 2016. The data then statistically analyzed using the Grads software package. While the process of WMT at the designated research location was evaluated together between the Artificial Rain Unit of BPPT (Agency for the Assessment and Application Technology), and the Engineering Faculty, University of Riau, 2016. The research showed that the WMT increased the rainfall rates during the dry season within the study area by 8% (520.7 mm to 557 mm) in the 3 months period (July 14 -October 6, 2016), and reducing significantly hotspots by 88.6% from 6.725 in 2014 to 770 in 2016. Hence, it confirmed that the application of technical WMT procedures may increase precipitation rates and reduce the number of hot spots in Bengkalis.

New Mechanisms of Mercury Binding to Peat

NASA Astrophysics Data System (ADS)

Nagy, K. L.; Manceau, A.; Gasper, J. D.; Ryan, J. N.; Aiken, G. R.

2007-12-01

Mercury can be immobilized in the aquatic environment by binding to peat, a solid form of natural organic matter. Binding mechanisms can vary in strength and reversibility, and therefore will control concentrations of bioreactive mercury, may explain rates of mercury methylation, and are important for designing approaches to improve water quality using natural wetlands or engineered phytoremediation schemes. In addition, strong binding between mercury and peat is likely to result in the fixation of mercury that ultimately resides in coal. The mechanisms by which aqueous mercury at low concentrations reacts with both dissolved and solid natural organic matter remain incompletely understood, despite recent efforts. We have identified three distinct binding mechanisms of divalent cationic mercury to solid peats from the Florida Everglades using EXAFS spectroscopic data (FAME beamline, European Synchrotron Radiation Facility (ESRF)) obtained on experimental samples as compared to relevant references including mercury-bearing solids and mercury bound to various organic molecules. The proportions of the three molecular configurations vary with Hg concentration, and two new configurations that involve sulfur ligands occur at Hg concentrations up to about 4000 ppm. The binding mechanism at the lowest experimental Hg concentration (60-80 ppm) elucidates published reports on the inhibition of metacinnabar formation in the presence of Hg-bearing solutions and dissolved natural organic matter, and also, the differences in extent of mercury methylation in distinct areas of the Florida Everglades.

The peats of Costa Rica (in English; Spanish)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thayer, G.R.

Peat has been identified in Cost Rica, and an economic analysis of energy applications for peat has been done. About 1000 km{sup 2} of Cost Rica has the potential of being covered by peat. The Talamanca Mountains and the northeastern plains contain most of the Costa Rican peat. Specific bogs have been identified by the Medio Queso River in north-central Costa Rica and near El Cairo, Moin, and the Limon airport in northeastern Costa Rica. The Medio Queso bog, which is supplying peat for use as a carrier for nitrogen-fixing bacteria, and the El Cairo bog, which has been identifiedmore » as a source of horticultural peat for nearby ornamental plant farms, are of special interest. The economics of three energy applications of peat were examined -- as a fuel in large boilers, as a fuel in small boilers, and as an oil substitute in a cement plant. A facility using coal would have the same total costs as one using peat if coal prices were $45 and $30 per metric ton (used for large boilers and a cement plant, respectively). A facility using Bunker C or diesel would have the same total cost as one using peat if oil prices were $0.11, $0.08, and $0.06 per liter (used for large boilers, small boilers, and a cement plant, respectively). In all three cases, the costs for peat were comparable or less than the costs for coal and oil at 1987 prices. 6 refs., 8 figs.« less

Formation of lacustrine plains in west-central Alaska as a result of permafrost degradation and aggradation

NASA Astrophysics Data System (ADS)

Kanevskiy, M. Z.; Jorgenson, M. T.; Shur, Y.; O'Donnell, J.; Harden, J. W.; Fortier, D.

2012-12-01

Perennially frozen lacustrine sediments containing a large amount of ground ice comprise a significant part of the upper permafrost of the lowlands of west-central Alaska, including Koyukuk Flats and Innoko Flats. Study sites are located in the discontinuous permafrost zone, where permafrost was encountered mainly within uplifted peat plateaus. The upper part of studied sections is formed by frozen peat up to 3 m thick underlain by lacustrine silt, which is mostly ice-rich. Cryogenic structure of lacustrine sediments at different sites has common features: (1) prevalence of layered, braided, and reticulate cryostructures; (2) high variability in the ice content of sediments; (3) high density and low water content of soil aggregates separated by ice lenses. Volume of visible ice in silt reaches at places 40% and more. The thickness of ice lenses generally varies from 1 to 5 cm and occasionally reaches 10 cm. Remnants of peat plateaus are surrounded by unfrozen bogs and fens, formed as a result of thawing and settling of ice-rich lacustrine silt. Modern thermokarst scars initially form at places where ice-rich silt is not protected by a thick layer of organic material. Further development of thermokarst bogs includes lateral enlargement of thaw bulbs and collapsing of the margins of peat plateaus. Lacustrine silt within taliks is covered by woody peat accumulated under forests during the stage of permafrost plateau formation and then by aquatic sphagnum peat accumulated in taliks after collapse. We relate the formation of ice-rich lacustrine sediments to development of lake thermokarst, which affected ice-rich silty yedoma deposits during the transition from Pleistocene to Holocene. Terrain development in lacustrine lowlands of west-central Alaska includes five stages related to permafrost aggradation and degradation from the late Pleistocene to the present time: 1) formation of the ice-rich syngenetic permafrost (yedoma) during the late Pleistocene; 2) yedoma degradation in the yearly Holocene and formation of thaw lakes; 3) complete yedoma degradation under thaw lakes and refreezing of thawed sediments at elevated areas; 4) peat accumulation and freezing of sediments in thaw lake basins; and 5) new cycle of thermokarst and formation of taliks under thaw lakes, bogs and fens. Stages of terrain development of lacustrine lowlands since the Late Pleistocene

Degradation of Malaysian peatlands decreases levels of phenolics in soil and in leaves of Macaranga pruinosa

NASA Astrophysics Data System (ADS)

Yule, Catherine; Lim, Yau; Lim, Tse

2016-04-01

Indo-Malaysian tropical peat swamp forests (PSF) sequester enormous stores of carbon in the form of phenolic compounds, particularly lignin as well as tannins. These phenolic compounds are crucial for ecosystem functioning in PSF through their inter-related roles in peat formation and plant defenses. Disturbance of PSF causes destruction of the peat substrate, but the specific impact of disturbance on phenolic compounds in peat and its associated vegetation has not previously been examined. A scale was developed to score peatland degradation based on the three major human impacts that affect tropical PSF - logging, drainage and fire. The objectives of this study were to compare the amount of phenolic compounds in Macaranga pruinosa, a common PSF tree, and in the peat substrate along a gradient of peatland degradation from pristine peat swamp forest to cleared, drained and burnt peatlands. We examined phenolic compounds in M. pruinosa and in peat and found that levels of total phenolic compounds and total tannins decrease in the leaves of M.pruinosa and also in the surface peat layers with an increase in peatland degradation. We conclude that waterlogged conditions preserve the concentration of phenolic compounds in peat, and that even PSF that has been previously logged but which has recovered a full canopy cover will have high levels of total phenolic content (TPC) in peat. High levels of TPC in peat and in the flora are vital for the inhibition of decomposition of organic matter and this is crucial for the accretion of peat and the sequestration of carbon. Thus regional PSF flourish despite the phenolic rich, toxic, waterlogged, nutrient poor, conditions, and reversal of such conditions is a sign of degradation.

The Impact of Tropical Peat Fire on Termite Assemblage in Sumatra, Indonesia: Reduced Complexity of Community Structure and Survival Strategies.

PubMed

Neoh, Kok-Boon; Bong, Lee-Jin; Muhammad, Ahmad; Itoh, Masayuki; Kozan, Osamu; Takematsu, Yoko; Yoshimura, Tsuyoshi

2016-10-01

Tropical peat swamp forests in Southeast Asia account for approximately 72% of global peatland. However, extensive forest exploitation following peat drainage for agricultural expansion has been leading to catastrophic peat fires. In this study, we compared the termite assemblage in burnt and unburnt peats in Sumatra, Indonesia. We also identified which taxonomic group is particularly resistant to fire disturbance and the traits that correlate with its persistence in fire-impacted peatlands. Overall, the termite species richness in fire-impacted peats was up to 40% lower than that of the total species found in peat swamp forests. Although the estimated species richness values in fire-impacted peats and peat swamp forests were not significantly different, fire changed termite community structure significantly. Only termites of the family Rhinotermitidae survived in the fire event, whereas members of the Termitidae that were reportedly resilient to fire and open habitats elsewhere disappeared during the fire events. The rhinotermitids found in the burnt sites were exclusively wood nesters. This suggests that the desiccation tolerance of termites in open habitat is not the simple underlying survival strategy, but tree branches and barks might have provided a refuge from heat during fire. The result also suggests that the high similarity in species composition in recently burnt peats and long burnt peats implies low species turnover. Thus, regardless of how much time had passed since the fire-impacted peats were abandoned or cultivated, the increase in habitat complexity did not favor colonization by the forest-dependent group. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The paleoecology, peat chemistry and carbon storage of a discontinuous permafrost peatland

NASA Astrophysics Data System (ADS)

Talbot, Julie; Pelletier, Nicolas; Olefeldt, David; Turetsky, Merritt; Blodau, Christian; Sonnentag, Oliver; Quinton, William

2017-04-01

Permafrost in peatlands strongly influences ecosystem biogeochemical functioning, vegetation composition and hydrological functions. Permafrost peatlands of northwestern Canada store large amounts of carbon but the peatlands located at the southern margin of the permafrost zone are thawing rapidly. This thaw triggers changes in vegetation, hydrology and peat characteristics, and may affect carbon stocks. We present data from a permafrost plateau to thermokarst bog chronosequence located in the southern portion of the Scotty Creek watershed near Fort Simpson, Northwest Territories, Canada. We assessed changes in plant communities, hydrology, biogeochemistry and permafrost status over 9000 years of peatland development using plant macrofossil, testate amoeba and peat chemical characteristics. Peat accumulation started after the infilling of a lake 8500 cal. yr BP. Minerotrophic peat prevailed at the site until permafrost formed around 5000 cal. yr BP. Permafrost apparently formed three times, although there is spatial variability in the permafrost aggradation - degradation cycles. Permafrost thawed 550 cal. yr BP in the center of the thermokarst bog. Ombrotrophic peat is a fairly recent feature of the peat profiles, only appearing after the most recent permafrost thaw event. Both allogenic (temperature/precipitation/snow cover changes and wildfire) and autogenic (peat accumulation, Sphagnum growth) processes likely influenced permafrost aggradation and thaw. While apparent carbon accumulation rates were lower during present and past permafrost periods than during non-permafrost periods, long term carbon accumulation remained similar between cores with different permafrost period lengths. Deep peat was more decomposed in the thermokarst bog peat profile than in the permafrost plateau profile, highlighting the importance of considering potential deep peat carbon losses to project the fate of thawing permafrost peat carbon stores. Average long-term carbon accumulation derived from the peat cores (n=3, 20.6 ± 1.9 g C m-2 a-1) is in the same range than the contemporary landscape-scale carbon balance measured from eddy covariance at the site ( 15 g C m-2 a-1). While the carbon to nitrogen ratio tends to decrease with peat depth, the carbon to phosphorus ratio tends to increase, perhaps indicating a preferential uptake of phosphorus over nitrogen by plants.

Effects of Humic Acids Isolated from Peat of Various Origin on in Vitro Production of Nitric Oxide: a Screening Study.

PubMed

Trofimova, E S; Zykova, M V; Ligacheva, A A; Sherstoboev, E Yu; Zhdanov, V V; Belousov, M V; Yusubov, M S; Krivoshchekov, S V; Danilets, M G; Dygai, A M

2016-09-01

A screening study of biological activity of native humic acids isolated from peat was performed; several physical and chemical parameters of their structures were studied by UV- and infrared spectroscopy. Spectroscopy yielded similar shape of light absorption curves of humic acids of different origin, which can reflect similarity of general structural principles of these substances. Alkaline humic acids have more developed system of polyconjugation, while molecular structures of pyrophosphate humic acids were characterized by higher aromaticity and condensation indexes. Biological activity of the studied humic acids was assessed by NO-stimulating capacity during their culturing with murine peritoneal macrophages in a wide concentration range. It was shown that due to dose-dependent enhancement of NO production humic acids can change the functional state of macrophages towards development of pro-inflammatory properties. These changes were associated with high activity of humic acids isolated by pyrophosphate extraction, which allows considering effects of isolation method on biological activity.

Dissolved Organic Carbon in Marginal, Damaged Peatlands: Using 14C to Understand DOC Losses

NASA Astrophysics Data System (ADS)

Luscombe, D.; Grand-Clement, E.; Garnett, M.; Anderson, K.; Gatis, N.; Benaud, P.; Brazier, R.

2013-12-01

Peatlands are widely represented throughout the world and act as an important store of carbon, as well as providing society with a range of other ecosystem services, such as drinking water or the support of rare habitats. However, the combination of historical management practices, and the predicted impact of climate change means that they are now largely under threat. In the shallow peatlands of Exmoor National Park (South West UK), peat cutting and intensive drainage in the 19th and 20th century for agricultural reclamation have changed the hydrological behaviour of the peat. This damage has dried out the upper layers, causing oxidation, erosion and vegetation change. In addition, their location on the southernmost limit of peatlands geographical extent in northern Europe makes them particularly vulnerable to the predicted changes in rainfall and temperature. Recent modelling work has shown that such marginal peatlands may disappear as early as 2050. Restoration programs are currently in place, aiming to restore the hydrological functioning of the peat. However, current dissolved organic carbon (DOC) losses from damaged peatlands are especially of concern, because of the contribution of the aquatic pathways in the C flux, and because of the impact on water quality. DOC has been shown to originate from the drainage of highly-aged organic matter. In stream waters, DOC from low flow tends to contain a larger component of older C compared to that of high flow. Both the impact of extensive drainage on where DOC is originating from and the effect of peatland restoration on this process remain poorly understood. We used 14C dating of DOC from streams and pore water, as well as from damaged peat, in order to gain a better understanding of the process and origin of DOC loss in drained shallow peatlands. This will further help us understand the potential for peatland restoration. Work was carried out in a small intensively monitored catchment in Exmoor. Samples were taken in an area of shallow peat (ca. 20-30 cm depth) drained by a medium size ditch (50 x 50 cm). Samples of DOC from stream water were taken at low and high flow during 3 separate rain events in Winter- Spring 2013 using automatic pump samplers. Samples of DOC in pore water were taken 2 m away from the ditch at 5 and 15 cm depth on two occasions. Finally, matching bulk peat samples were collected at 5 and 15 cm depth. Intensive monitoring data also provides information on water table depth and level in streams. A neighbouring pristine peat area was used as a control, and DOC pore water and bulk peat soil samples were taken at 5, 15 and 45 cm depth on two occasions. Preliminary results show that DOC lost in streams at high flow contains a greater contribution of bomb-14C compared to that at low flow (107 and 101 % modern respectively). Stream water DOC at low flow had a 14C concentration lower than that in pore water at both 5 and 15 cm depth (105 and 102% modern, respectively), suggesting that low flow stream water DOC is predominantly older than that found in pore water at depth.

Fens, seasonal wetlands, and the unconfined pumice aquifer east of the Cascade Range, south-central Oregon

NASA Astrophysics Data System (ADS)

Cummings, M. L.; Large, A.; Mowbray, A.; Weatherford, J.; Webb, B.

2013-12-01

Fens and seasonal wetlands in the headwaters of the Klamath and Deschutes river basins in south-central Oregon are present in an area blanketed by 2 to 3 m of pumice during the Holocene eruption of Mount Mazama. The lower pumice unit, moderately sorted coarse pumice lapilli to blocks (0.3 to 0.7 cm), phenocrysts, and lithics is 1.5 to 2 m thick; the upper pumice unit, poorly sorted lapilli to blocks (0.2 to 6 cm), minor phenocrysts, and lithics is 1 m thick. Pumice is a perched, unconfined aquifer over low permeability bedrock or pre-eruption fine-grained sediment. Early landscape response included partial erosion of pumice from pre-eruption valleys followed by partial filling by alluvium: phenocryst- and lithic-rich sand grading upward to glassy silt with rounded pumice pebbles. Groundwater-fed wetlands, fens, associated with the unconfined pumice aquifer occur as areas of diffuse groundwater discharge through gently sloping, convex surfaces underlain by up to 1.4 m of peat. Locally, focused discharge through the confining peat layer feeds low discharge streams. Carnivorous plants (sundews and pitcher plants) may be present. The sharp contact between peat and underlying pumice is an erosion surface that cuts progressively deeper into the upper and lower pumice units downslope. At the base of the slope peat with fen discharge feeding surface flow, alluvium with no surface flow, or a subtle berm separating the slope underlain by peat from the valley bottom underlain by alluvium may be present. Distinct vegetation changes take place at this transition. The erosion surface that underlies the peat layer in the fen is at the surface on the opposing valley wall and progressively rises up through the lower and upper pumice units: iron staining and cementation of pumice is locally prominent. Up to 1.5 m difference in water table occurs between the fen and opposing valley wall. Water table in piezometers screened in peat is at the surface. Locally, water table screened in pumice below the peat confining layer is up to 24 cm above the surface. Electrical conductivity in groundwater from the unconfined pumice aquifer ranged between 20 and 45 μS/cm. Rarely, electrical conductivity greater than 250 μS/cm is measured. Hydrochemistry indicates these waters are distinctly different (Ca-bicarbonate, [Fe] up to 22 mg/l) from water commonly encountered in the unconfined pumice aquifer (Na-bicarbonate, [Fe] less than 0.07 mg/l). Seasonally elevated water tables are present where pre-eruption topography allows snowmelt to accumulate in the unconfined pumice aquifer in valley bottoms and upland surfaces. Differential hardness of volcanic bedrock units control distribution in valley bottoms; emplacement processes and weathering of flow tops control distribution in upland settings. In both settings the lower pumice unit is saturated, but the upper pumice unit may be absent or thin. Alluvium commonly overlies pumice in valley bottoms. The water table may fluctuate up to 1.5 m from the spring snowmelt to late summer. Electrical conductivity in the pumice aquifer ranges between 19 and 250 μS/cm and commonly increases at single sites as the dry season progresses.

Influence of peat on Fenton oxidation.

PubMed

Huling, S G; Arnold, R G; Sierka, R A; Miller, M R

2001-05-01

A diagnostic probe was used to estimate the activity of Fenton-derived hydroxyl radicals (.OH), reaction kinetics, and oxidation efficiency in batch suspensions comprised of silica sand, crushed goethite (alpha-FeOOH) ore, peat, and H2O2 (0.13 mM). A simple method of kinetic analysis is presented and used to estimate the rate of .OH production (POH) and scavenging term (ks), which were used to establish the influence of organic matter (Pahokee peat) in Fenton systems. POH was greater in the peat-amended systems than in the unamended control, and ks was approximately the same. Any increase in scavenging of .OH that resulted from the addition of peat was insignificant in comparison to radical scavenging by reaction with H2O2. Also, treatment efficiency, defined as the ratio of probe conversion to H2O2 consumption over the same period was greater in the peat-amended system. Results suggest that .OH production is enhanced in the presence of peat by one or more peat-dependent mechanisms. Fe concentration and availability in the peat, reduction of Fe(III) to Fe(II) by the organic matter, and reduction of organic-complexed Fe(III) to Fe(II) are discussed in the context of the Fenton mechanism.

Isotopic evidence for nitrogen mobility in peat bogs

NASA Astrophysics Data System (ADS)

Novak, Martin; Stepanova, Marketa; Jackova, Ivana; Vile, Melanie A.; Wieder, R. Kelman; Buzek, Frantisek; Adamova, Marie; Erbanova, Lucie; Fottova, Daniela; Komarek, Arnost

2014-05-01

Elevated nitrogen (N) input may reduce carbon (C) storage in peat. Under low atmospheric deposition, most N is bound in the moss layer. Under high N inputs, Sphagnum is not able to prevent penetration of dissolved N to deeper peat. Nitrogen may become available to the roots of invading vascular plants. The concurrent oxygenation of deeper peat layers, along with higher supply of labile organic C, may enhance microbial decomposition and lead to peat thinning. The resulting higher emissions of greenhouse gases may accelerate global warming. Seepage of N to deeper peat has never been quantified. Here we present evidence for post-depositional mobility of atmogenic N in peat, based on natural-abundance N isotope ratios. We conducted a reciprocal peat transplant experiment between two Sphagnum-dominated peat bogs in the Czech Republic (Central Europe), differing in anthropogenic N inputs. The northern site VJ received as much as 33 kg N ha-1 yr-1 via spruce canopy throughfall. The southern site was less polluted (17.6 kg N ha-1 yr-1). Isotope signatures of living moss differed between the two sites (δ15N of -3‰ and -7‰ at VJ and CB, respectively). After 18 months, an isotope mass balance was constructed. In the CB-to-VJ transplant, a significant portion of original CB nitrogen (98-31%) was removed and replaced by nitrogen of the host site throughout the top 10 cm of the profile. Nitrogen, deposited at VJ, was immobilized in imported CB peat that was up to 20 years old. Additionally, we compared N concentration and N accumulation rates in 210Pb-dated peat profiles with well-constrained data on historical atmospheric N pollution. Nationwide N emissions peaked in 1990, while VJ exhibited the highest N content in peat that formed in 1930. This de-coupling of N inputs and N retention in peat might be interpreted as a result of translocation of dissolved pollutant N downcore, corroborating our δ15N results at VJ and CB. Data from a variety of peat bogs along pollution and climatic gradients would be needed to test to what extent the record of atmospheric N inputs in peat is overprinted by variable, locally-controlled decomposition rates.

Facies development in the Lower Freeport coal bed, west-central Pennsylvania, U.S.A.

USGS Publications Warehouse

Pierce, B.S.; Stanton, R.W.; Eble, C.F.

1991-01-01

The Lower Freeport coal bed in west-central Pennsylvania is interpreted to have formed within a lacustrine-mire environment. Conditions of peat formation, caused by the changing chemical and physical environments, produced five coal facies and two mineral-rich parting facies within the coal bed. The coal bed facies are compositionally unique, having developed under varying conditions, and are manifested by megascopic, petrographic, palynologic and quality characteristics. The initial environment of the Lower Freeport peat resulted in a coal facies that is relatively high in ash yield and contains large amounts of lycopod miospores and moderate abundances of cryptotelinite, crypto-gelocollinite, inertinite and tree fern miospores. This initial Lower Freeport peat is interpreted to have been a topogenous body that was low lying, relatively nutrient rich (mesotrophic to eutrophic), and susceptible to ground water and to sediment influx from surface water. The next facies to form was a ubiquitous, clay-rich durain parting which is attributed to a general rise in the water table accompanied by widespread flooding. Following formation of the parting, peat accumulation resumed within an environment that inhibited clastic input. Development of doming in this facies restricted deposition of the upper shale parting to the margins of the mire and allowed low-ash peat to form in the interior of the mire. Because this environment was conducive to preservation of cellular tissue, this coal facies also contains large amounts of crypto-telinite. This facies development is interpreted to have been a transitional phase from topogenous, planar peat formation to slightly domed, oligotrophic (nutrient-poor) peat formation. As domed peat formation continued, fluctuations in the water table enabled oxidation of the peat surface and produced high inertinite concentrations toward the top of the coal bed. Tree ferns became an increasingly important peat contributor in the e upper facies, based on the palynoflora. This floral change is interpreted to have resulted from the peat surface becoming less wet or better drained, a condition that inhibited proliferation of lycopod trees. Accumulation of the peat continued until rising water levels formed a freshwater lake within which clays and silts were deposited. The development of the Lower Freeport peat from a planar mire through transitional phases toward domed peat formation may be an example of the type of peat formation of other upper Middle and Upper Pennsylvanian coal beds. ?? 1991.

An immunological approach to quantifying the saprotrophic growth dynamics of Trichoderma species during antagonistic interactions with Rhizoctonia solani in a soil-less mix.

PubMed

Thornton, Christopher R

2004-04-01

Studies of the saprotrophic growth dynamics of Trichoderma species and their fungal hosts during antagonistic interactions are severely hampered by the absence of methods that allow the unambiguous identification and quantification of individual genera in complex environments such as soil or compost containing mixed populations of fungi. Furthermore, methods are required that allow discrimination between active hyphal growth and other components of fungal biomass such as quiescent spores that are produced in large numbers by Trichoderma species. This study details the use of monoclonal antibodies to quantify the saprotrophic growth dynamics of the soil-borne plant pathogen Rhizoctonia solani and biological control strains of Trichoderma asperellum and Trichoderma harzianum during antagonistic interactions in peat-based microcosms. Quantification was based on the immunological detection of constitutive, extracellular antigens that are secreted from the growing tip of Rhizoctonia and Trichoderma mycelium and, in the case of Trichoderma harzianum, from quiescent phialoconidia also. The Trichoderma-specific monoclonal antibody (MF2) binds to a protein epitope of the enzyme glucoamylase, which was shown by immunofluorescence and immunogold electron gold microscopy studies of Trichoderma virens in vitro to be produced at the origin of germ tube emergence in phialoconidia and from the growing tip of germ tubes. In addition, a non-destructive immunoblotting technique showed that the enzyme was secreted during active growth of Trichoderma asperellum mycelium in peat. The Rhizoctonia solani-specific monoclonal antibody (EH2) similarly binds to a protein epitope of a glycoprotein that is secreted during active mycelial growth. Extracts derived from lyophilized mycelium were used as a quantifiable and repeatable source of antigens for construction of calibration curves. These curves were used to convert the absorbance values obtained in ELISA tests of peat extracts to biomass equivalents, which allowed comparisons of the saprotrophic growth dynamics of the pathogen and antagonists to be made in single or mixed species microcosms. Trichoderma species were able to compete successfully with R. solani for nutrients and to prevent saprotrophic growth of the pathogen. Specificity of the Trichoderma quantitative assay was tested in non-sterile soil-based microcosms artificially inoculated with T. asperellum. The assay was highly specific and only detected T. asperellum population dynamics. No cross-reactivity was found with extracts from soil samples containing contaminant fungi.

Factors controlling peat chemistry and vegetation composition in Sudbury peatlands after 30 years of pollution emission reductions.

PubMed

Barrett, Sophie E; Watmough, Shaun A

2015-11-01

The objective of this research was to assess factors controlling peat and plant chemistry, and vegetation composition in 18 peatlands surrounding Sudbury after more than 30 years of large (>95%) pollution emission reductions. Sites closer to the main Copper Cliff smelter had more humified peat and the surface horizons were greatly enriched in copper (Cu) and nickel (Ni). Copper and Ni concentrations in peat were significantly correlated with that in the plant tissue of Chamaedaphne calyculata. The pH of peat was the strongest determining factor for species richness, diversity, and community composition, although percent vascular plant cover was strongly negatively correlated with surface Cu and Ni concentrations in peat. Sphagnum frequency was also negatively related to peat Cu and Ni concentrations indicating sites close to Copper Cliff smelter remain adversely impacted by industrial activities. Copyright © 2015 Elsevier Ltd. All rights reserved.

Coastal Landforms and Accumulation of Mangrove Peat Increase Carbon Sequestration and Storage

NASA Astrophysics Data System (ADS)

Costa, M. T.; Excurra, P.; Ezcurra, E.; Garcillan, P. P.; Aburto-Oropeza, O.

2016-02-01

Many studies have highlighted the considerable belowground carbon storage of mangroves and other coastal ecosystems (as much 30% of total ocean carbon storage). Mangroves are among the most carbon-rich forests in the tropics, containing on average more than 1,000 Mg C/ha. We sampled mangrove sediments in four locations along the Pacific Coast of Mexico, from the Baja California Sur in the north to Chiapas near the Guatemalan boarder. These sites varied in their coastal geomorphology and rainfall regimes. The mangroves of rainy Chiapas possessed the deepest and most carbon-rich Rhizophora peat deposits of any of the sites (in places more than 2,000 Mg/ha). More surprisingly, in Balandra, one of the desert mangrove lagoons of Baja California Sur, the Avicennia-dominated mudflat zone of the forest possessed deep and rich peat deposits, ranging from 400-1,300 Mg/ha. This forest, hemmed in by relatively steep hillsides demonstrates the potential for mangroves to accrete carbon-rich peat vertically when local topography precludes their landwards expansion with sea-level rise. Our microscopic examination of root fibers from these peat deposits revealed the importance of Avicennia to the formation of buried organic matter deposits. We used 14C dating to track the age of the Baja California deposits, whose ages ranged between 1193 and 1636 BP. Plotting the calibrated 14C age of each peat sample from Balandra against the depth of the sample below the mean sea-level, we found a very significant linear trend (r2 = 0.87, P < 0.0001) with a slope of 0.070 ±0.007 mm/yr. Belowground carbon sequestration rates during recent decades varied from very low (ca. 0.1 Mg.ha-1.yr-1) in a receding fringe in Bahía Magdalena or a halophilic hinterland in Balandra, to 9-20 Mg.ha-1.yr-1 in a Rhizophora mudflat in La Encrucijada. With only 0.49% of the total area, the mangroves around the Gulf of California store 18% of the total belowground carbon pool of the whole region, 76 Tg in total.

Fluvial organic carbon losses from oil palm plantations on tropical peat, Sarawak, Southeast Asia

NASA Astrophysics Data System (ADS)

Cook, Sarah; Page, Susan; Evans, Chris; Whelan, Mick; Gauci, Vincent; Lip Khoon, Kho

2017-04-01

Tropical peatlands are valuable stores of carbon. However, tropical peat swamp forests (TPSFs) in Southeast Asia have increasingly been converted to other land-uses. For example, more than 25% of TPSFs are now under oil palm plantations. This conversion - requiring felling and burning of trees and drainage of the peat - can enhance carbon mineralization, dissolved organic carbon (DOC) losses and can contribute significantly to global anthropogenic greenhouse gas emissions, changing these natural carbon sinks into carbon sources. At present, relatively few scientifically sound studies provide dependable estimates of gaseous and fluvial carbon losses from oil palm plantations or from drained tropical peat in general. Here we present an annual (54 week) estimate of the export of dissolved and particulate organic carbon in water draining two oil palm estates and nearby stands of TPSF in Sarawak, Malaysia, subjected to varying degrees of past anthropogenic disturbance. Spectrophotometric techniques including SUVA254 (Specific Ultra-Violet Absorption) were used to gain insight into the aromaticity and subsequent bioavailability of the exported DOC. Water draining plantation and deforested land had a higher proportion of labile carbon compared to water draining forested areas. Preliminary data suggest a total fluvial DOC flux from plantations of ca. 190 g C m-2 year-1; nearly three times estimates from intact TPSFs (63 g C m-2 year-1). DOC accounted for between 86 % - 94 % of the total organic carbon lost (most of which was bioavailable). Wit et al. (2015) estimates that an average of 53 % of peat-derived DOC is decomposed and emitted as CO2, on a monthly basis. Based on these estimates our data suggests an additional 101 g CO2 m-2 may be emitted indirectly from fluvial organic carbon in degraded TPSFs per year. Overall, these findings emphasize the importance of including fluvial organic carbon fluxes when quantifying the impact of anthropogenic disturbance on the peatland carbon budget. Given the increasing expansion of oil palm plantations on tropical peat, within Southeast Asia, it is essential that fluvial organic carbon data is incorporated into assessment criteria, helping countries to better monitor, report and verify their land-based greenhouse gas emissions.

ORCHIDEE-PEAT (revision 4596), a model for northern peatland CO2, water, and energy fluxes on daily to annual scales

NASA Astrophysics Data System (ADS)

Qiu, Chunjing; Zhu, Dan; Ciais, Philippe; Guenet, Bertrand; Krinner, Gerhard; Peng, Shushi; Aurela, Mika; Bernhofer, Christian; Brümmer, Christian; Bret-Harte, Syndonia; Chu, Housen; Chen, Jiquan; Desai, Ankur R.; Dušek, Jiří; Euskirchen, Eugénie S.; Fortuniak, Krzysztof; Flanagan, Lawrence B.; Friborg, Thomas; Grygoruk, Mateusz; Gogo, Sébastien; Grünwald, Thomas; Hansen, Birger U.; Holl, David; Humphreys, Elyn; Hurkuck, Miriam; Kiely, Gerard; Klatt, Janina; Kutzbach, Lars; Largeron, Chloé; Laggoun-Défarge, Fatima; Lund, Magnus; Lafleur, Peter M.; Li, Xuefei; Mammarella, Ivan; Merbold, Lutz; Nilsson, Mats B.; Olejnik, Janusz; Ottosson-Löfvenius, Mikaell; Oechel, Walter; Parmentier, Frans-Jan W.; Peichl, Matthias; Pirk, Norbert; Peltola, Olli; Pawlak, Włodzimierz; Rasse, Daniel; Rinne, Janne; Shaver, Gaius; Schmid, Hans Peter; Sottocornola, Matteo; Steinbrecher, Rainer; Sachs, Torsten; Urbaniak, Marek; Zona, Donatella; Ziemblinska, Klaudia

2018-02-01

Peatlands store substantial amounts of carbon and are vulnerable to climate change. We present a modified version of the Organising Carbon and Hydrology In Dynamic Ecosystems (ORCHIDEE) land surface model for simulating the hydrology, surface energy, and CO2 fluxes of peatlands on daily to annual timescales. The model includes a separate soil tile in each 0.5° grid cell, defined from a global peatland map and identified with peat-specific soil hydraulic properties. Runoff from non-peat vegetation within a grid cell containing a fraction of peat is routed to this peat soil tile, which maintains shallow water tables. The water table position separates oxic from anoxic decomposition. The model was evaluated against eddy-covariance (EC) observations from 30 northern peatland sites, with the maximum rate of carboxylation (Vcmax) being optimized at each site. Regarding short-term day-to-day variations, the model performance was good for gross primary production (GPP) (r2 = 0.76; Nash-Sutcliffe modeling efficiency, MEF = 0.76) and ecosystem respiration (ER, r2 = 0.78, MEF = 0.75), with lesser accuracy for latent heat fluxes (LE, r2 = 0.42, MEF = 0.14) and and net ecosystem CO2 exchange (NEE, r2 = 0.38, MEF = 0.26). Seasonal variations in GPP, ER, NEE, and energy fluxes on monthly scales showed moderate to high r2 values (0.57-0.86). For spatial across-site gradients of annual mean GPP, ER, NEE, and LE, r2 values of 0.93, 0.89, 0.27, and 0.71 were achieved, respectively. Water table (WT) variation was not well predicted (r2 < 0.1), likely due to the uncertain water input to the peat from surrounding areas. However, the poor performance of WT simulation did not greatly affect predictions of ER and NEE. We found a significant relationship between optimized Vcmax and latitude (temperature), which better reflects the spatial gradients of annual NEE than using an average Vcmax value.

Growing reforestation conifer stock: Utilizing peat/sawdust medium

Treesearch

Janice K. Schaefer

2009-01-01

Western Forest Systems, Incorporated (WFS) (Lewiston, ID) has been utilizing a peat/sawdust blended mix as our growing medium for the past 10 years. Our decision to change from a peat/vermiculite blend to a peat/Douglas-fir (Pseudotsuga menziesii) sawdust blend involved worker health and safety issues, seedling culture, seedling production, and...

Spatial variation of peat soil properties in the oil-producing region of northeastern Sakhalin

NASA Astrophysics Data System (ADS)

Lipatov, D. N.; Shcheglov, A. I.; Manakhov, D. V.; Zavgorodnyaya, Yu. A.; Rozanova, M. S.; Brekhov, P. T.

2017-07-01

Morphology and properties of medium-deep oligotrophic peat, oligotrophic peat gley, pyrogenic oligotrophic peat gley, and peat gley soils on subshrub-cotton grass-sphagnum bogs and in swampy larch forests of northeastern Sakhalin have been studied. Variation in the thickness and reserves of litters in the studied bog and forest biogeocenoses has been analyzed. The profile distribution and spatial variability of moisture, density, ash, and pHKCl in separate groups of peat soils have been described. The content and spatial variability of petroleum hydrocarbons have been considered in relation to the accumulation of natural bitumoids by peat soils and the technogenic pressing in the oil-producing region. Variation of each parameter at different distances (10, 50, and 1000 m) has been estimated using a hierarchical sampling scheme. The spatial conjugation of soil parameters has been studied by factor analysis using the principal components method and Spearman correlation coefficients. Regression equations have been proposed to describe relationships of ash content with soil density and content of petroleum hydrocarbons in peat horizons.

A Database and Synthesis of Northern Peatland Soil Properties and Holocene Carbon and Nitrogen Accumulation

NASA Technical Reports Server (NTRS)

Loisel, Julie; Yu, Zicheng; Beilman, David W.; Camill, Philip; Alm, Jukka; Amesbury, Matthew J.; Anderson, David; Andersson, Sofia; Bochicchio, Christopher; Barber, Keith;

Physicochemical properties of hydrothermally treated peat fuel obtained from Mempawah-West Kalimantan: influence of hydrophilicity index on carbon aromaticity and combustibility

NASA Astrophysics Data System (ADS)

Mursito, Anggoro Tri; Hirajima, T.; Listiyowati, L. N.

2018-02-01

Mempawah peat of West Kalimantan was selected as raw material for studying the physicochemical properties of peat fuel products and their characteristic in the hydrothermal upgrading process at a temperature range of 150°C to 380°C at an average heating rate of 6.6°C/min for 30 minutes. The 13C NMR spectra revealed changes in the effect of temperature on carbon aromaticity of raw peat and peat fuel products which were in 0.39 to 0.63 as the temperature increased. Other phenomenon occurring during the experiment was hydrophilicity index of peat fuel surface decreases of about 1.7 and 1.4 with increased treatment temperature. We also found that hydrothermal upgrading also affected the combustion properties of peat fuel products. Ignition temperature of raw peat and solid products were at 175°C and between 188°C to 285°C respectively. Temperature at the maximum combustion rate of raw peat and solid products was at 460°C, and between 477°C to 509°C were suggested to the increasing of reactivity of solid products respectively. Here, we discussed several phenomenon of the peat fuel product during hydrothermal process with a respect to the change in the physicochemical properties as determined by Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric and Differential Thermal Analysis (TG-DTA) analyses, 13C NMR and also other supporting analytical equipment.

Age Determination of the Remaining Peat in the Sacramento-San Joaquin Delta, California, USA

USGS Publications Warehouse

Drexler, Judith Z.; de Fontaine, Christian S.; Knifong, Donna L.

2007-01-01

Introduction The Sacramento-San Joaquin Delta of California was once a 1,400 square kilometer (km2) tidal marsh, which contained a vast layer of peat ranging up to 15 meters (m) thick (Atwater and Belknap, 1980). Because of its favorable climate and highly fertile peat soils, the majority of the Delta was drained and reclaimed for agriculture during the late 1800s and early 1900s. Drainage of the peat soils changed the conditions in the surface layers of peat from anaerobic (having no free oxygen present) to aerobic (exposed to the atmosphere). This change in conditions greatly increased the decomposition rate of the peat, which consists largely of organic (plant) matter. Thus began the process of land-surface subsidence, which initially was a result of peat shrinkage and compaction, and later largely was a result of oxidation by which organic carbon in the peat essentially vaporized to carbon dioxide (Deverel and others, 1998; Ingebritsen and Ikehara, 1999). Because of subsidence, the land-surface elevation on farmed islands in the Delta has decreased from a few meters to as much as 8 m below local mean sea level (California Department of Water Resources, 1995; Steve Deverel, Hydrofocus, Inc., written commun., 2007). The USGS, in collaboration with the University of California at Davis, and Hydrofocus Inc. of Davis, California, has been studying the formation of the Delta and the impact of wetland reclamation on the peat column as part of a project called Rates and Evolution of Peat Accretion through Time (REPEAT). The purpose of this report is to provide results on the age of the remaining peat soils on four farmed islands in the Delta.

The thin brown line: The crucial role of peat in protecting permafrost in Arctic Alaska

NASA Astrophysics Data System (ADS)

Gaglioti, B.; Mann, D. H.; Farquharson, L. M.; Baughman, C. A.; Jones, B. M.; Romanovsky, V. E.; Williams, A. P.; Andreu-Hayles, L.

2017-12-01

Ongoing warming threatens to thaw Arctic permafrost and release its stored carbon, which could trigger a permafrost-carbon feedback capable of augmenting global warming. The effects of warming air temperatures on permafrost are complicated by the fact that across much of the Arctic and Subarctic a mat of living plants and decaying litter cover the ground and buffer underlying permafrost from air temperatures. For simplicity here, we refer to this organic mat as "peat". Because this peat modifies heat flow between ground and air, the rate and magnitude of permafrost responses to changing climate - and hence the permafrost-carbon feedback - are partly slaved to the peat layer's slower dynamics. To explore this relationship, we used 14C-age offsets within lake sediments in Alaskan watersheds underlain by yedoma deposits to track the changing responses of permafrost thaw to fluctuating climate as peat accumulated over the last 14,000 years. As the peat layer built up, warming events became less effective at thawing permafrost and releasing ancient carbon. Consistent with this age-offset record, the geological record shows that early in post-glacial times when the peat cover was still thin and limited in extent, warm intervals triggered extensive thermokarst that resulted in rapid aggradation of floodplains. Today in contrast, hillslopes and floodplains remain stable despite rapid warming, probably because of the buffering effects of the extensive peat cover. Another natural experiment is provided by tundra fires like the 2007 Anaktuvuk River fire that removed the peat cover from tundra underlain by continuous permafrost and resulted in widespread thermkarsting. Further support for peat's critical role in protecting permafrost comes from the results of modeling how permafrost temperatures under different peat thicknesses respond to warming air temperature. Although post-industrial warming has not yet surpassed the buffering capacity of 14,000 years of peat buildup in Arctic Alaska, modeling suggests that a threshold is imminent.

Electron transfer properties of peat organic matter: from electrochemical analysis to redox processes in peatlands

NASA Astrophysics Data System (ADS)

Sander, Michael; Getzinger, Gordon; Walpen, Nicolas

2017-04-01

Peat organic matter contains redox-active functional groups that can accept and/or donate electrons from and to biotic and abiotic reaction partners present in peatlands. Several studies have provided evidence that electron accepting quinone moieties in the peat organic matter may act as terminal electron acceptors for anaerobic microbial respiration. This respiration pathway may competitively suppress methanogenesis and thereby lead to excess carbon dioxide to methane formation in peatlands. Electron donating phenolic moieties in peat organic matter have long been considered to inhibit microbial and enzymatic activities in peatlands, thereby contributing to carbon stabilization and accumulation in these systems. Phenols are expected to be comparatively stable in anoxic parts of the peats as phenoloxidases, a class of enzymes capable of oxidatively degrading phenols, require molecular oxygen as co-substrate. Despite the general recognition of the importance of redox-active moieties in peat organic matter, the abundance, redox properties and reactivities of these moieties remain poorly studied and understood, in large part due to analytical challenges. This contribution will, in a first part, summarize recent advances in our research group on the analytical chemistry of redox-active moieties in peat organic matter. We will show how mediated electrochemical analysis can be used to quantify the capacities of electron accepting and donating moieties in both dissolved and particulate peat organic matter. We will link these capacities to the physicochemical properties of peat organic matter and provide evidence for quinones and phenols as major electron accepting and donating moieties, respectively. The second part of this contribution will highlight how these electroanalytical techniques can be utilized to advance a more fundamental understanding of electron transfer processes involving peat organic matter. These processes include the redox cycling (i.e., repeated reduction and re-oxidation) of peat organic matter under alternating anoxic-oxic conditions as well as the oxidation of phenolic moieties in peat organic matter by phenol oxidases in the presence of molecular oxygen. Overall, this contribution will attempt to link molecular-level insights into the redox properties of peat organic matter to larger scale redox processes that are important to carbon cycling in peatlands.

Can a novel combination of organic chemical analysis and inverse modeling help reconstruct the past upper forest line in the Ecuadorian Andes?

NASA Astrophysics Data System (ADS)

Jansen, B.; van Loon, E. E.; Nierop, K. G. J.

2009-04-01

The higher parts of the Ecuadorian Andes consist of fragile ecosystems characterized by páramo grasslands and montane cloud forests. Natural climatic change and human interference (i.a. burning and clear-cutting) are believed to have dramatically lowered the UFL in the area to the point that its natural position in the absence of disturbance is now uncertain. This is impeding our understanding of the response of the UFL to global climate change and hindering a correct strategy to reforest areas in the frame of Kyoto Protocol driven activities to fix carbon dioxide. An important cause of the uncertainty is that the traditional method of pollen analysis from peat or sediment deposits alone does not suffice to reconstruct shifts in the UFL. Reasons are the spatial uncertainty caused by wind-blown dispersal of pollen and the limited availability of peat or sediment deposits at all altitudes of interest. The RUFLE* program tackles this problem by combining traditional pollen and vegetation analyses with a novel biomarker approach. In the latter, plant species typical for specific vegetation zones are examined for the presence of biomarkers, defined as plant-specific (combinations of) organic chemical components. Our results show that the leaves and roots of the higher plants responsible for the dominant biomass input in our study area in the Eastern Cordillera in the Northern Ecuadorian Andes contain unique combinations of n-alkanes and n-alcohols in the carbon number range of C20-C36(1). Furthermore, we found these compounds to be well preserved in peat deposits and soils in chronological order for extended time periods (>6000 14C years B.P.)(2,3). As such they offer great potential to serve as biomarkers for past vegetation dynamics, including UFL shifts. However, since it are unique combinations of otherwise ubiquitous n-alkanes, n-alcohols of various carbon chain-lengths that constitute our biomarkers, unraveling the mixed signal of various plants accumulated in soils and peat sediment over time poses a major challenge. To tackle this problem, we developed the VERHIB model that describes the accumulation of biomarkers in soils and peat sediments(4). By inversion the most likely vegetation composition leading to the mixed biomarker signal in the soil or peat sediment in question can be derived. Here we describe the results of the first application of the model in a peat core and several soil monoliths at various altitudes from our study area. Our results show that biomarker analysis using the VERHIB model can indeed serve as a new proxy to reconstruct historic vegetation compositions including the UFL in the Ecuadorian Andes, yielding information that is highly complementary to that which can be obtained through traditional pollen analysis. This is a significant breakthrough from a paleo-ecological point of view as it means an additional proxy is available to be used in combination with traditional pollen- and vegetation analysis. In addition, it is a very promising result from an applied point of view as the information gained will aid the Ecuadorian government in its strategic decisions concerning reforestation of possibly degraded natural areas. 1)Jansen, B. Nierop, K.G.J., Hageman, J.A., Cleef, A.M. & Verstraten, J.M. 2006. The straight chain lipid biomarker composition of plant species responsible for the dominant biomass production along two altitudinal transects in the Ecuadorian Andes. Organic Geochemistry 37: 1514-1536. 2)Jansen, B. & Nierop, K.G.J. 2008. Methyl ketones in high altitude Ecuadorian Andosols confirm excellent conservation of plant-specific n-alkane patterns. Organic Geochemistry (in press). 3)Tonneijck, F.H. & Jongmans, A.G. 2008. The influence of bioturbation on the vertical distribution of soil organic matter in volcanic ash soils: a case study in Northern Ecuador. European Journal of Soil Science 59: 1063-1075. 4)Jansen, B., Van Loon, E.E., Hooghiemstra, H. & Verstraten, J.M. 2008. Analysis of plant biomarkers greatly improves reconstruction of palaeo-environments. Geology (submitted). *RUFLE stands for Reconstruction of the Upper Forest Line in Ecuador

Tangled history of the European uses of Sphagnum moss and sphagnol.

PubMed

Drobnik, Jacek; Stebel, Adam

2017-09-14

Sphagnum mosses and peat could have been utilized as wound dressings for centuries, however reliable data on this subject are ambiguous; sometimes even no distinction between peat moss (Sphagnum spp.) and peat is made or these terms become confused. The first scientific account on surgical use of peat comes from 1882: a peat digger who successfully, by himself and in the way unknown to the then medicine, cured an open fracture of his forearm with peat. The peat, and very soon the peat moss itself (which is the major constituent of peat) drew attention of the 19th-century surgeons. We search for reliable information on: (1) inspirations for Sphagnum usage for medical purposes and its beginnings in the 19th century, (2) substances or products named sphagnol and their connections with (1); (3) on the origin of this name, (4) and on the occurrence of this name in medical sources. We have identified and studied published sources on the uses of peat-based and Sphagnum-based preparations and products of any processing level (including herbal stock, distillate, isolated pure or impure active principle, or a mixture of such) in surgery, pharmacy or cosmetics. A special attention was paid to the name sphagnol, which appeared many a time, in more than one context since 1899. Source publications were critically analysed from the taxonomical, pharmacognostical and ethnopharmacological points of view. Gathered data were cross-checked with the modern knowledge of the biologically active principles of Sphagnum and the prospects of their medical use. The application of peat in surgery started 1882. The use of peat moss as dressings was developed in the 1880's. It returned to surgical practice during WW1. The name sphagnol has two meanings: (1) A chemical substance isolated from the cell walls of Sphagnum mosses in 1899. A post-1950 research showed it to be a mixture of phenols dominated by sphagnum acid. (2) A product of dry distillation of peat contains solid and liquid fractions and was applied in skin diseases due to antiseptic properties. It was added to ointments and medicated soaps manufactured up to the late 1960's. Today none of these two sphagnols is in use. Surgical application of peat had an ethnopharmacological origin: a case of wound treatment with peat as a remedy rather than a dressing (1880, published 1882) shortly shifted the surgeons' attention to peat moss as an absorptive dressing. The 1880's tests of antiseptic properties of peat and peat moss failed, the sterilization methods overrode the physiological effects of Sphagnum dressings. Sphagnan, a polysaccharide from Sphagnum cell walls, discovered 1983, inhibits microbial growth, tans the collagen and removes ammonia from microbial environments. Portions of raw peat could be sterile. The isolation of sphagnol (1899) from Sphagnum cell walls was not inspired by old surgery. Main component of sphagnol, the sphagnic acid, was used clinically during WW2, but was proved a weak antimicrobial agent. A homonymous name sphagnol appeared independently for a product of dry distillation of peat, introduced commercially probably about 1899, too, which gave rise to confusions: a) the commercial, "distilled" sphagnol was not the crystalline principle of Sphagnum cell walls. 2) the "distilled" sphagnol was hardly defined technologically or pharmacologically, never standardized in terms of the substrate (a variety of peat rather than Sphagnum herb) and the production process. This sphagnol, resembling pitch or tar, was an additive to medicated soaps and ointments for skin treatment and care. It must have been a low-scale product although advertised worldwide. Neither sphagnum acid nor sphagnan are used medicinally today. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Holocene climate dynamics in the Eastern Italian Alps: a multi-proxy study from ice and peat bogs

NASA Astrophysics Data System (ADS)

Poto, Luisa; Gabrieli, Jacopo; Segnana, Michela; Festi, Daniela; Oeggl, Klaus; Barbante, Carlo

2014-05-01

The Eastern Italian Alps are located near one of the areas in the world with some of the longest records of extreme environmental use by human activity. In this area, paleo-climate studies are hampered by the lack of high-resolution multi-proxy records with adequate chronological control. With this project, we propose to reconstruct Holocene climatic and environmental variations in the Eastern Italian Alps using terrestrial and glaciological archives. We aim to study the characteristics of different climate stages in this sector of the Alps using an ice core drilled on the top of the Ortles glacier (46°30' N, 10°32 E, 3850 m a.s.l.) and ombrotrophic peat bog records from the Dolomites (Danta di Cadore, 46°34' N, 12°33 E, 1400 m a.s.l. and Coltrondo 46°39'28.37''N 12°26'59.17''E, 1800 m a.s.l., Belluno province). The study of global climatic change require a holistic and multi-proxy approach to better understand several complex and often non-linear relationships. In the Italian Alps our study on peat cores represents the first attempt where a multi-proxy approach is applied, and here we report our first results. A 7.0 m peat sequence was extracted in Danta di Cadore. The depth-age scale, based upon independent 14C and 210Pb dates and modeled with the Clam method (Blaauw, 2010), demonstrates that the archive covers more than 13,200 years (cal BP). We determined physical proprieties, Ca and Ti trends, pore water pH, conductivity, and Ca/Mg ratios to identify changes in trophic conditions. The results confirm that the uppermost 400 cm are composed of ombrotrophic peat representing the longest Eastern Alpine ombrotrophic record yet obtained, covering the last 7,000 years. The oldest radiocarbon age (13,200 years cal BP) provides evidence that, during the Bölling-Alleröd interstadial, the upper part of the Piave Glacier was ice-free up to 1400 m a.s.l.. At that time pollen assemblages show that a conifer forest characterized the local vegetation. This forest was then affected by the climatic cooling of the Younger Dryas, which caused an opening of the vegetation. The climatic amelioration occurring at the onset of the Holocene favored the local expansion of warmth-demanding species. X-ray Fluorescence Core Scanner (XRF-CS) analysis was applied for the first time on Eastern Alpine peat sequences. XRF-CS signals were calibrated with ICP-MS, showing very high correlation and demonstrating that the XRF-CS technique provides reliable quantitative data. Results provide information about geochemical processes occurring in the bog. The impact of mining activity was also evaluated. Concentration levels and enrichment factors (EFs) of several trace elements such as Pb, Ag and Cd correspond to the historical data about mining activities in the Cadore region. Lead isotopes ratios were measured to identify natural and anthropogenic sources of Pb emissions. Results show an increase of Pb deriving from fuel combustion over the last decades that gradually overlie the impacts of mining activity. The decreasing 206Pb/207Pb trend reached its minimum value of 1.153 in the 1990s and then increased again. In these years, Italy started to follow EU rules to limit global pollutants in the atmosphere, and finally banned leaded fuels in 2002. Both 206Pb/207Pb ratio and Pb fluxes show a particular event between 1975 and 1980: this behavior is characteristic of the ILE (Isotopic Lead Experiment), a large-scale isotopic tracer experiment which was carried out in the Piedmont region (N-W Italy). This multi-proxy approach that integrates, using new chronological insights, chemical physical and biological features of the core, improves our understanding of Eastern Alpine Holocene climate, helping to delineate biotic and abiotic responses to climate dynamics during the present interglacial. Blaauw, M. 2010. Methods and code for 'classical' age modeling of radiocarbon sequences. Quarternary Geochronology, 5: 512-518.

The Peat Marwick/AS&U Compensation Survey for School Executives.

ERIC Educational Resources Information Center

American School and University, 1986

1986-01-01

A total of 396 districts responded from all 50 states and the District of Columbia to this survey about administrative positions, with full-time teachers as a comparison point, in the areas of base salaries, bonuses, benefits, and perquisites. (MLF)

Mixing of Marine and Terrestrial Sources of Strontium in Coastal Environments

NASA Astrophysics Data System (ADS)

Ryan, Saskia; Crowley, Quentin; Deegan, Eileen; Snoeck, Christophe

2017-04-01

87Sr/86Sr from bulk soils, soil extracts and plant material have been used to investigate and quantify the extent of marine-derived Sr in the terrestrial biosphere. Samples were collected along coastal transects and 87Sr/86Sr biosphere values (plant and soil) converge to marine values with increasing proximity to the coast. R2values indicate highly significant trends in certain regions. The National Soils Database (NSDB), TELLUS and TELLUS Border datasets, all of which are geochemical surveys have been employed to further test the extent of marine elemental contribution. Collectively these data cover all of Ireland and Northern Ireland, with varying degrees of sampling density. A strong spatial correlation exists between the Chemical Index of Alteration (CIA; (Al2O3-(CaO*+Na2O)-K2O)) in topsoil (CIA <60; 27% n = 11651) and areas of blanket peat. The enrichment of Ca and Na in these regions would suggest a significant marine geochemical contribution. Topsoil CIA can therefore be used to identify areas likely to feature significant marine inputs and identify regions where the 87Sr/86Sr budget may deviate from bedrock values.

Development of recent chronologies and evaluation of temporal variations in Pb fluxes and sources in lake sediment and peat cores in a remote, highly radiogenic environment, Cairngorm Mountains, Scottish Highlands

NASA Astrophysics Data System (ADS)

Farmer, John G.; MacKenzie, Angus B.; Graham, Margaret C.; Macgregor, Kenneth; Kirika, Alexander

2015-05-01

The use of stable Pb isotope analyses in conjunction with recent (210Pb and anthropogenic radionuclide) chronologies has become a well-established method for evaluating historical trends in depositional fluxes and sources of atmospherically deposited Pb using archival records in lake sediment or peat cores. Such studies rely upon (i) simple radioactive disequilibrium between unsupported 210Pb and longer-lived members of the 238U decay series and (ii) well-defined values for the isotopic composition of contaminant Pb and indigenous Pb in the study area. However, areas of high natural radioactivity can present challenging environments for such studies, with potential complications arising from more complex disequilibria in the 238U decay series and the occurrence, at local or regional level, of anomalous, ill-defined stable isotope ratios due to the presence of elevated levels of radiogenic Pb. Results are presented here for a study of a sediment core from a freshwater lake, Loch Einich, in the high natural radioactivity area of the Cairngorm Mountains of Scotland. 238U decay series disequilibria revealed recent diagenetic re-deposition of both U and 226Ra, the latter resulting in a requirement to use a modified calculation to derive a 210Pb chronology for the core. Confidence in the chronology was provided by good agreement with the independent 241Am chronology, but the 137Cs distribution was affected by significant post-depositional mobility in the organic-rich sediment. The systematics of variations in 230Th, 232Th and stable Pb isotope ratio distributions were used to establish the indigenous Pb characteristics of the sediment. The relatively high radiogenic content of the indigenous Pb resulted in complications in source apportionment, in particular during the 20th century, with multiple natural and anthropogenic sources precluding the use of a simple binary mixing model. Consequently, 206Pb/207Pb ratios in Scottish moss samples from an archive collection were used to provide the input term for atmospheric deposition in order to establish historical trends in indigenous and anthropogenic Pb fluxes. A test of the accuracy of the derived Pb fluxes was provided by analysis of a core from a nearby blanket peat deposit, Great Moss. Independent atmospheric and basal inputs gave a complex distribution of 210Pb in the peat, but this did not affect calculation of a 210Pb chronology. Once again, the 210Pb chronology was supported by the 241Am distribution. Temporal trends in anthropogenic Pb deposition derived for the Loch Einich sediment core were in generally good agreement with those for the Great Moss peat core, other peat cores and some other lake sediment cores from northern Scotland, providing confidence in the use of the archive moss data to characterise atmospheric deposition. However, sustained input of Pb to Loch Einich sediment at relatively high levels in the late 20th century, after the regional decline in atmospheric Pb deposition, suggested that catchment-derived Pb is now a significant component of the depositional flux for Loch Einich.

Diamondoid hydrocarbons as a molecular proxy for thermal maturity and oil cracking: Geochemical models from hydrous pyrolysis

USGS Publications Warehouse

Wei, Z.; Moldowan, J.M.; Zhang, S.; Hill, R.; Jarvie, D.M.; Wang, Hongfang; Song, F.; Fago, F.

2007-01-01

A series of isothermal hydrous pyrolysis experiments was performed on immature sedimentary rocks and peats of different lithology and organic source input to explore the generation of diamondoids during the thermal maturation of sediments. Oil generation curves indicate that peak oil yields occur between 340 and 360 ??C, followed by intense oil cracking in different samples. The biomarker maturity parameters appear to be insensitive to thermal maturation as most of the isomerization ratios of molecular biomarkers in the pyrolysates have reached their equilibrium values. Diamondoids are absent from immature peat extracts, but exist in immature sedimentary rocks in various amounts. This implies that they are not products of biosynthesis and that they may be generated during diagenesis, not just catagenesis and cracking. Most importantly, the concentrations of diamondoids are observed to increase with thermal stress, suggesting that they can be used as a molecular proxy for thermal maturity of source rocks and crude oils. Their abundance is most sensitive to thermal exposure above temperatures of 360-370 ??C (R0 = 1.3-1.5%) for the studied samples, which corresponds to the onset of intense cracking of other less stable components. Below these temperatures, diamondoids increase gradually due to competing processes of generation and dilution. Calibrations were developed between their concentrations and measured vitrinite reflectance through hydrous pyrolysis maturation of different types of rocks and peats. The geochemical models obtained from these methods may provide an alterative approach for determining thermal maturity of source rocks and crude oils, particularly in mature to highly mature Paleozoic carbonates. In addition, the extent of oil cracking was quantified using the concentrations of diamondoids in hydrous pyrolysates of rocks and peats, verifying that these hydrocarbons are valuable indicators of oil cracking in nature. ?? 2006 Elsevier Ltd. All rights reserved.

Bacterial populations and environmental factors controlling cellulose degradation in an acidic Sphagnum peat.

PubMed

Pankratov, Timofey A; Ivanova, Anastasia O; Dedysh, Svetlana N; Liesack, Werner

2011-07-01

Northern peatlands represent a major global carbon store harbouring approximately one-third of the global reserves of soil organic carbon. A large proportion of these peatlands consists of acidic Sphagnum-dominated ombrotrophic bogs, which are characterized by extremely low rates of plant debris decomposition. The degradation of cellulose, the major component of Sphagnum-derived litter, was monitored in long-term incubation experiments with acidic (pH 4.0) peat extracts. This process was almost undetectable at 10°C and occurred at low rates at 20°C, while it was significantly accelerated at both temperature regimes by the addition of available nitrogen. Cellulose breakdown was only partially inhibited in the presence of cycloheximide, suggesting that bacteria participated in this process. We aimed to identify these bacteria by a combination of molecular and cultivation approaches and to determine the factors that limit their activity in situ. The indigenous bacterial community in peat was dominated by Alphaproteobacteria and Acidobacteria. The addition of cellulose induced a clear shift in the community structure towards an increase in the relative abundance of the Bacteroidetes. Increasing temperature and nitrogen availability resulted in a selective development of bacteria phylogenetically related to Cytophaga hutchinsonii (94-95% 16S rRNA gene sequence similarity), which densely colonized microfibrils of cellulose. Among isolates obtained from this community only some subdivision 1 Acidobacteria were capable of degrading cellulose, albeit at a very slow rate. These Acidobacteria represent indigenous cellulolytic members of the microbial community in acidic peat and are easily out-competed by Cytophaga-like bacteria under conditions of increased nitrogen availability. Members of the phylum Firmicutes, known to be key players in cellulose degradation in neutral habitats, were not detected in the cellulolytic community enriched at low pH. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

Storms in a lagoon: the flooding history of Schokland (Noordoostpolder, The Netherlands) during the last 1200 years derived from geological and historical archives

NASA Astrophysics Data System (ADS)

Van den Biggelaar, Don; Kluiving, Sjoerd; Van Balen, Ronald; Kasse, Kees

2013-04-01

Flevoland (central part of the Netherlands) is an area of long-term discontinuous deposition, which has been reclaimed from the Zuiderzee in the 20th century. The Zuiderzee was an inlet of the North Sea, which came into existence during Medieval times at the expense of vast peat swamps. The inhabitants of the Zuiderzee area have a long tradition of living and struggling with water. For Schokland, located in the northern part of Flevoland (The Netherlands) and its inhabitants, this tradition started at around AD 800 when peat formation came to an end in the former Flevo lagoon region. Since that time, a surficial clay cover was deposited on Schokland. The top of the peat underlying the clay is dated at ~1200 BP, while the top is dated up to ~70 BP, implying that the clay was deposited during the Medieval to Recent occupation of the former Flevo lagoon region. We have studied the clay sequence with the combined use of geological and historical archives in order to determine the most recent flooding history of Flevoland (last 1200 years). Field data, lab analyses (grainsize anlyses, TOC, pollen, microfossils) and a literature study show that storm events had a major impact on both the sedimentary and the anthropogenic history of Schokland. A comparison between geological data and documented historical storms is made and possible remnants of the eleven major storm events, mentioned in the historical sources, that eroded parts of Schokland are identified in the subsurface of the area in the form of spikes with coarser sediment relative to the background sedimentation.

Spatial variability of active layer thickness detected by ground-penetrating radar in the Qilian Mountains, Western China

NASA Astrophysics Data System (ADS)

Cao, Bin; Gruber, Stephan; Zhang, Tingjun; Li, Lili; Peng, Xiaoqing; Wang, Kang; Zheng, Lei; Shao, Wanwan; Guo, Hong

2017-03-01

The active layer plays a key role in geomorphic, hydrologic, and biogeochemical processes in permafrost regions. We conducted a systematic investigation of active layer thickness (ALT) in northeastern Qinghai-Tibetan Plateau by using ground-penetrating radar (GPR) with 100 and 200 MHz antennas. We used mechanical probing, pit, and soil temperature profiles for evaluating ALT derived from GPR. The results showed that GPR is competent for detecting ALT, and the error was ±0.08 m at common midpoint co-located sites. Considerable spatial variability of ALT owing to variation in elevation, peat thickness, and slope aspect was found. The mean ALT was 1.32 ± 0.29 m with a range from 0.81 to 2.1 m in Eboling Mountain. In Yeniu Gou, mean ALT was 2.72 ± 0.88 m and varied from 1.07 m on the north-facing slope to 4.86 m around the area near the lower boundary of permafrost. ALT in peat decreased with increasing elevation at rates of -1.31 m/km (Eboling Mountain) and -2.1 m/km (Yeniu Gou), and in mineral soil in Yeniu Gou, the rate changed to -4.18 m/km. At the same elevation, ALT on the south-facing slope was about 0.8 m thicker than that on the north-facing slopes, while the difference was only 0.18 m in peat-covered area. Within a 100 m2 area with a local elevation difference of 0.8 m, ALT varied from 0.68 m to 1.25 m. Both field monitoring and modeling studies on spatial ALT variations require rethinking of the current strategy and comprehensive design.

Comparative Study of Emission Factors and Mutagenicity of ...

EPA Pesticide Factsheets

Wildfire events produce massive amounts of smoke and thus play an important role in local and regional air quality as well as public health. It is not well understood however if the impacts of wildfire smoke are influenced by fuel types or combustion conditions. Here we developed a novel combustion and sample-collection system that features an automated tube furnace to control combustion conditions and a multistage cryotrap system to efficiently collection particulate and semi-volatile phases of smoke emissions. The furnace sustained stable flaming and smoldering biomass (red oak and peat) burning conditions consistently for ~60 min. The multi-stage cryo-trap system (-10°C followed by -47°C, and ending in -70°C sequential impingers) collected up to 90% (by mass) of the smoke. Condensates were extracted and assessed for mutagenicity (polycyclic aromatic hydrocarbons (PAHs)- and nitroarene-type activity) in Salmonella strains TA100 and TA98+/-S9. Carbon dioxide, carbon monoxide (CO), and particulate matter (PM) concentrations monitored continuously during the combustion process were used to calculate modified combustion efficiency (MCE) and emission factors (EFs). We found that the MCE during smoldering conditions was 74% and 71% and during flaming conditions was 99% and 96% for red oak and peat, respectively. Red oak smoldering EFs for CO and PM were 209 g/kg and 147 g/kg, whereas flaming EFs were 16 g/kg and 0.6 g/kg, respectively. Peat smoldering EF

Vinegar residue compost as a growth substrate enhances cucumber resistance against the Fusarium wilt pathogen Fusarium oxysporum by regulating physiological and biochemical responses.

PubMed

Shi, Lu; Du, Nanshan; Yuan, Yinghui; Shu, Sheng; Sun, Jin; Guo, Shirong

2016-09-01

Fusarium wilt caused by the fungus Fusarium oxysporum f. sp. cucumerinum (FOC) is the most severe soil-borne disease attacking cucumber. To assess the positive effects of vinegar residue substrate (VRS) on the growth and incidence of Fusarium wilt on cucumber, we determined the cucumber growth parameters, disease severity, defense-related enzyme and pathogenesis-related (PR) protein activities, and stress-related gene expression levels. In in vitro and pot experiments, we demonstrated the following results: (i) the VRS extract exhibited a higher biocontrol activity than that of peat against FOC, and significantly improved the growth inhibition of FOC, with values of 48.3 %; (ii) in response to a FOC challenge, antioxidant enzymes and the key enzymes of phenylpropanoid metabolic activities, as well as the PR protein activities in the roots of cucumber, were significantly increased. Moreover, the activities of these proteins were higher in VRS than in peat; (iii) the expression levels of stress-related genes (including glu, pal, and ethylene receptor) elicited responses to the pathogens inoculated in cucumber leaves; and (iv) the FOC treatment significantly inhibited the growth of cucumber seedlings. Moreover, all of the growth indices of plants grown in VRS were significantly higher than those grown in peat. These results offer a new strategy to control cucumber Fusarium wilt, by upregulating the activity levels of defense-related enzymes and PR proteins and adjusting gene expression levels. They also provide a theoretical basis for VRS applications.

Environmental changes, forest history and human impact in the southern part of Valdai Hills (European Russia) during the last 7000 years

NASA Astrophysics Data System (ADS)

Novenko, Elena; Tsyganov, Andery; Pisarchuk, Natalia; Kozlov, Daniil

2017-04-01

Understanding the long-term ecological dynamics of swampy boreal forest is essential for assessment of the possible responses and feedbacks of forest ecosystems to climate change and natural disturbance. The multi-proxy record from the Central Forest State Natural Biosphere Reserve (CFSNBR), locate on the South of Valdai Hills, provides important new data on the forest history, human impact, paludification dynamics and environmental changes in the central part of the East European Plain during the Holocene. The results of peat humification, pollen, plant macrofossil, micro charcoal and testate amoeba analyses from forest pealand show that between 7000 and 4000 cal yr BP the southern part of Valdai Hills was occupied by broad-leaved forests. Spruce occurred in forest communities as small admixture and gradually increased its abundance. After 4000 cal yr BP spruce rapidly become the main forest forming species, however broad-leaved trees took place in plant cover. Despite significant climatic fluctuation, mixed broad-leaved-spruce forests persisted in vegetation until 900 cal yr BP and then were replaced by waterlogged herbal spruce forests. The extensive Sphagnum spruce forests are recent plant communities and were formed during the last 100 years that could be explain by changes in water balance of the territory due to both climate and anthropogenic factors. According to reconstruction of Mid- and Late Holocene climate changes, warm and relatively dry period of the Holocene Thermal Maximum (7000-5500 cal yr BP) was followed by climate cooling that included several relatively cold phases at about 5000, 3500, 2000, 1200 cal yr BP and warm intervals at about 2600, 1500 and 900 cal yr BP. The distinct cooling was reconstructed between 800 and 400 cal yr BP, apparently, correlated with the Little Ice Age. Climate dynamics appeared as significant changes of environmental conditions at local ecosystem. Warming phases are indicated by high peat humification and organic matter content and relatively low peat accumulation rates. Peat deposits poses sign of several fire episodes. During cool and humid phases the rate of vertical and lateral peat growth increased, while degree of peat decomposition become lower. Dramatic changes in environmental conditions in the study area and changes in trends of ecosystem dynamics occurred during the last 400-350 year. The obtained results suggest evident climate warming, significant increase in surface wetness and increase fivefold of peat accumulation rates. During the last hundred years, the local wetness in the studied localities became considerably higher that promoted the growth of Sphagnum mosses and overall transformation of forest stands to Sphagnum spruce forests. Evidences of significant human impact on the area about 300-250 cal yr BP were detected by indicator species in pollen analysis and reconstructions of woodland coverage by BMA approach. The modern vegetation of the Reserve may develop from a plant cover with mosaic pattern that included not only the mature spruce forests but also secondary birch woodlands, meadows and agricultural lands. This study was supported by the Russian Science Foundation (Grant 16-17-10045).

PILOT PEAT-BED TREATMENT SYSTEM FOR NPDES OUTFALL H-12

DOE Office of Scientific and Technical Information (OSTI.GOV)

Halverson, N; Ralph Nichols, R; Topher Berry, T

2007-10-22

A National Pollutant Discharge Elimination System (NPDES) Permit was issued to the Savannah River Site (SRS) by the South Carolina Department of Health and Environmental Control (SCDHEC) and became effective on December 1, 2003. The new permit contained revised limits for copper and zinc derived by adjusting the South Carolina aquatic life water quality standards in accordance with dissolved metals criteria. The new copper and zinc limits are very low and may not be met consistently at Outfall H-12. The outfall has periodically exceeded the new 6 {micro}g/l (0.006 mg/L) monthly average limit and the 8 {micro}g/l (0.008 mg/L) maximummore » limit for copper and recently has begun exceeding the 100 {micro}g/l (0.100 mg/L) limit for zinc. The compliance date for Outfall H-12 is November 1, 2008. A study was conducted on this outfall and other outfalls to evaluate possible alternatives for meeting the new permit limits (Shipman and Bugher 2004). The study team recommended construction of a peat bed for treatment of the Outfall H-12 effluent. This recommendation was repeated by a second alternatives study team in 2007 (WSRC 2007). A bench-scale laboratory study demonstrated the feasibility of peat-bed treatment for Outfall H-12 effluent, with the peat demonstrating excellent removal of copper (Nelson and Specht 2005). An additional study was performed in 2006 and early 2007 using vertical-flow peat columns to investigate the influence of water retention time (contact time) on the removal of copper and zinc from the water (Nelson 2007c). Analytical results indicated that copper removal was very high at each of the three retention times tested, ranging from 99.6% removal at five and three hours to 98.8% removal at one hour. Effluent copper levels from these studies were much lower than the new compliance limit for the outfall. Most divalent metals, including zinc, were removed to below their normal reporting detection limit. The H-Area Material Disposition organization requested a larger-scale study to investigate key design and operation parameters/issues, such as the possibility of rapid plugging of the piping or clogging of the peat bed, the effectiveness of the treatment, hydraulic conductivity, etc. The resulting pilot-scale facility was constructed adjacent to Outfall H-12 with SCDHEC approval (Mullinax 2007). The pilot-scale study was performed by the Savannah River National Laboratory's (SRNL) Environmental Science and Biotechnology Directorate personnel. Since the construction and operation of the pilot-scale peat bed facility, however, a new strategy for achieving compliance of Outfall H-12 effluent with the new permit limits has been selected. This new strategy incorporates a variety of efforts including source reduction, recalculation of limits using an aquatic species that is indigenous to the area instead of a standard species, and dissolved organic carbon addition to reduce copper toxicity. This report documents the construction and operation of the pilot-scale treatment system, the results obtained, and recommendations on the usefulness of this technology for Outfall H-12 or other outfalls at SRS.« less

Effectiveness of lime and peat applications on cadmium availability in a paddy soil under various moisture regimes.

PubMed

Chen, Yanhui; Xie, Tuanhui; Liang, Qiaofeng; Liu, Mengjiao; Zhao, Mingliu; Wang, Mingkuang; Wang, Guo

2016-04-01

In paddy soils, amendments and moisture play important role in the immobilization of cadmium (Cd). The effects of applying lime, peat, and a combination of both on soil Eh, pH, and Cd availability in contaminated soils were investigated under wetted (80 ± 5 % of water holding capacity) and flooded (completely submerged) conditions. In wetted soils, there was little change in Eh, compared to flooded soils where Eh reduced rapidly. Amendments of lime only or in a mixture with peat increased soil pH to different degrees, depending on the lime application rate. However, peat addition only slightly affected soil pH. The decreased Cd availability in flooded soils was related to submergence duration and was significantly lower than that in wetted soils after 14 days. Liming wetted and flooded soils decreased exchangeable Cd and increased carbonates or Fe-Mn oxides bound fractions, while peat addition transformed Cd from carbonates to organic matter bound fractions. The combined application of peat and lime generally showed better inhibitory effects on the availability of Cd than separately application of lime or peat. Higher application rates of lime, peat, or their mixture were more effective at reducing Cd contamination in flooded soil. This indicates that application of peat and lime mixture under flooded conditions was most effective for in situ remediation of Cd-contaminated soils. Further studies are required to assess the long-term effectiveness of the peat and lime mixture on Cd availability in paddy soils.

Peat accumulation in drained thermokarst lake basins in continuous, ice-rich permafrost, northern Seward Peninsula, Alaska

USGS Publications Warehouse

Jones, Miriam C.; Grosse, Guido; Jones, Benjamin M.; Anthony, Katey Walter

2012-01-01

Thermokarst lakes and peat-accumulating drained lake basins cover a substantial portion of Arctic lowland landscapes, yet the role of thermokarst lake drainage and ensuing peat formation in landscape-scale carbon (C) budgets remains understudied. Here we use measurements of terrestrial peat thickness, bulk density, organic matter content, and basal radiocarbon age from permafrost cores, soil pits, and exposures in vegetated, drained lake basins to characterize regional lake drainage chronology, C accumulation rates, and the role of thermokarst-lake cycling in carbon dynamics throughout the Holocene on the northern Seward Peninsula, Alaska. Most detectable lake drainage events occurred within the last 4,000 years with the highest drainage frequency during the medieval climate anomaly. Peat accumulation rates were highest in young (50–500 years) drained lake basins (35.2 g C m−2 yr−1) and decreased exponentially with time since drainage to 9 g C m−2 yr−1 in the oldest basins. Spatial analyses of terrestrial peat depth, basal peat radiocarbon ages, basin geomorphology, and satellite-derived land surface properties (Normalized Difference Vegetation Index (NDVI); Minimum Noise Fraction (MNF)) from Landsat satellite data revealed significant relationships between peat thickness and mean basin NDVI or MNF. By upscaling observed relationships, we infer that drained thermokarst lake basins, covering 391 km2 (76%) of the 515 km2 study region, store 6.4–6.6 Tg organic C in drained lake basin terrestrial peat. Peat accumulation in drained lake basins likely serves to offset greenhouse gas release from thermokarst-impacted landscapes and should be incorporated in landscape-scale C budgets.

Polycyclic aromatic hydrocarbons in post-fire soils of drained peatlands in western Meshchera (Moscow region, Russia)

NASA Astrophysics Data System (ADS)

Tsibart, A.; Gennadiev, A.; Koshovskii, T.; Watts, A.

2014-12-01

Polycyclic aromatic hydrocarbons (PAHs) are priority pollutants that arrive in the environment from numerous anthropogenic and natural sources, but the data on their natural sources including wildfires remain insufficient. The level of contamination and the composition of PAHs in soils of the areas affected by wildfires were studied in this work. The study was conducted in the Moscow region (Russia) in areas occupied by drained peatland and strongly damaged by fires in 2002, 2010 and 2012. The features of PAH accumulation and the profile distributions in histosols and histic podzols after the fires of different times were analyzed. It was shown that new soil horizons formed after the fires - Cpir, Hpir and incipient O horizons - and that these horizons differ in PAH accumulation rate. Maximal total concentrations of 14 PAHs were detected in charred peat horizons Hpir (up to 330 ng g-1) and in post-fire incipient O horizons (up to 180 ng g-1), but the high-molecular-weight PAHs (benz(ghi)perylene, benz(a)pyrene, benz(k)fluoranthene) were revealed only in charry peat horizons. The trends of higher PAH concentrations were found in cases when smoldering combustion resulted in rather thick residual peat horizons. In cases of almost complete pyrogenic destruction of He horizons, total PAH concentrations were no more than 50 ng g-1. Also, PAH accumulation in upper horizons of soils near the sites of the latest fires was observed.

A post-Calumet shoreline along southern Lake Michigan

USGS Publications Warehouse

Capps, D.K.; Thompson, T.A.; Booth, R.K.

2007-01-01

The southern shore of Lake Michigan is the type area for many of ancestral Lake Michigan's late Pleistocene lake phases, but coastal deposits and features of the Algonquin phase of northern Lake Michigan, Lake Huron, and Lake Superior are not recognized in the area. Isostatic rebound models suggest that Algonquin phase deposits should be 100 m or more below modern lake level. A relict shoreline, however, exists along the lakeward margin of the Calumet Beach that was erosional west of Deep River and depositional east of the river. For this post-Calumet shoreline, the elevation of basal foreshore deposits east of Deep River and the base of the scarp west of Deep River indicate a slightly westward dipping water plane that is centered at ???184 m above mean sea level. Basal foreshore elevations also indicate that lake level fell ???2 m during the development of the shoreline. The pooled mean of radiocarbon dates from the surface of the peat below post-Calumet shoreline foreshore deposits indicate that the lake transgressed over the peat at 10,560 ?? 70 years B.P. Pollen assemblages from the peat are consistent with this age. The elevation and age of the post-Calumet shoreline are similar to the Main Algonquin phase of Lake Huron. Recent isostatic rebound models do not adequately address a high-elevation Algonquin-age shoreline along the southern shore of Lake Michigan, but the Goldthwait (1908) hinge-line model does. ?? 2006 Springer Science+Business Media B.V.

Estimating of Gonystiluss Bancanus Growing Stock in Indonesia (Case study: Riau and Central Kalimantan)

NASA Astrophysics Data System (ADS)

Samsuri; Jaya, I. N. S.; Partomihardjo, T.

2017-03-01

Gonystylus bancanus is protected species because it is included in list of critically endangered plant species that is heading to be extinct. Export banned Gonystylus bancanus log trigger illegal logging caused ramin’s demand is high. This study aimed to estimate Gonystylus bancanus growing stock in Indonesia. Time series of satellite image was used to identify land use change. Spatial analysis by overlaying of land cover and peatland map found the potential habitat of Gonystylus bancanus. Cluster sampling method was applied to predict growing stock recently year. The study found that growing stock in peat swamp forest in Central Kalimantan (Sebangau National Park area) tend to be elevated. It is also occurred in production forest of peat swamp that is harvested, especially in concession area of Diamond Raya Timber Ltd that also tend to elevate. The most increasing of growing stock is caused by ingrowth). Growing of Gonystylus bancanus seedling is hardly occurred. It is caused by youngest seedling characteristics that are need a covering.. Gonystylus bancanus (growing stock is not be spread evenly overall growing stages. This study also found that Gonystylus bancanus growing stock ranging between 4.2 m3/ha to 15.2 m3/ha. The growing stock of Gonystylus bancanus is between 3.3% to 5.4% of all species in peat swamp forest. Average of Gonystylus bancanus increment about 0.63 m3/ha/year. Average growing stock of all species is 3.1 ∼ 20.5 m3/ha/year).

Uncertainty in peat volume and soil carbon estimated using ground-penetrating radar and probing

Treesearch

Andrew D. Parsekian; Lee Slater; Dimitrios Ntarlagiannis; James Nolan; Stephen D. Sebestyen; Randall K. Kolka; Paul J. Hanson

2012-01-01

Estimating soil C stock in a peatland is highly dependent on accurate measurement of the peat volume. In this study, we evaluated the uncertainty in calculations of peat volume using high-resolution data to resolve the three-dimensional structure of a peat basin based on both direct (push probes) and indirect geophysical (ground-penetrating radar) measurements. We...

Economics of selected energy applications of peat in Panama and Costa Rica

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thayer, G.R.; Ramirez E., O.; Ramirez, A.

Studies were performed to determine the economic competitiveness of peat in Costa Rica and Panama. The cases examined were (1) electrical production in Panama, and (2) industrial boilers and cement plants in Costa Rica. Based on estimates of peat mining costs and the end-use costs we calculated for each application, the price of coal and oil at which the levelized life cycle cost of energy using peat was the same as that when coal or oil was used. We found that a peat-fueled power plant in Panama would be economic if the price of fuel oil was above $0.10 permore » liter and the cost of coal was above $40.00 per metric ton delivered. In Costa Rica, peat was competitive with fuel oil for large boilers (34,000 kg of steam per hour) when the cost of oil was above $0.10 per liter. For smaller boilers (5,000 kg of steam per hour) peat was cheaper than fuel oil when oil was above $0.08 per liter. Peat would be competitive in a cement plant when fuel oil prices were above $0.075 per liter. 5 figs.« less

Comparative study of the thermal properties of mud and peat solutions applied in clinical practice.

PubMed

Beer, A M; Grozeva, A; Sagorchev, P; Lukanov, J

2003-11-01

Different peloids as e.g. mud and peat have been traditionally used for therapeutic purposes successfully, especially of there thermal actions. It was the aim of the experimental study to compare the thermal properties of two peloids, mud and peat, with a view to assessing their thermal effects when they are applied in clinical practice. The studies were carried out using peat of the marsh type of peats (Hochmoor), and curative Pomorie (Bulgaria) mud. As important parameters were determined the specific thermal capacity at constant pressure (Cp), the density of solutions (rho), the cooling rate (m), the coefficient of temperature transfer (a) of solutions and the coefficient of thermal conductivity (lambda) of solutions of peat and curative mud, compared to water bath. The comparative studies of the thermal properties of water and water solutions of peat and curative mud show that the thermal effect of the water bath is substantially smaller than that of the peat and mud applications. This difference is due to a greater extent to the high values of the dynamic viscosity, not allowing cooling by convection and protecting the surface of the skin upon applications of peloid solutions with a higher temperature.

Cardiopulmonary toxicity of peat wildfire particulate matter and the predictive utility of precision cut lung slices.

PubMed

Kim, Yong Ho; Tong, Haiyan; Daniels, Mary; Boykin, Elizabeth; Krantz, Q Todd; McGee, John; Hays, Michael; Kovalcik, Kasey; Dye, Janice A; Gilmour, M Ian

2014-06-16

Emissions from a large peat fire in North Carolina in 2008 were associated with increased hospital admissions for asthma and the rate of heart failure in the exposed population. Peat fires often produce larger amounts of smoke and last longer than forest fires, however few studies have reported on their toxicity. Moreover, reliable alternatives to traditional animal toxicity testing are needed to reduce the number of animals required for hazard identification and risk assessments. Size-fractionated particulate matter (PM; ultrafine, fine, and coarse) were obtained from the peat fire while smoldering (ENCF-1) or when nearly extinguished (ENCF-4). Extracted samples were analyzed for chemical constituents and endotoxin content. Female CD-1 mice were exposed via oropharyngeal aspiration to 100 μg/mouse, and assessed for relative changes in lung and systemic markers of injury and inflammation. At 24 h post-exposure, hearts were removed for ex vivo functional assessments and ischemic challenge. Lastly, 8 mm diameter lung slices from CD-1 mice were exposed (11 μg) ± co-treatment of PM with polymyxin B (PMB), an endotoxin-binding compound. On an equi-mass basis, coarse ENCF-1 PM had the highest endotoxin content and elicited the greatest pro-inflammatory responses in the mice including: increases in bronchoalveolar lavage fluid protein, cytokines (IL-6, TNF-α, and MIP-2), neutrophils and intracellular reactive oxygen species (ROS) production. Exposure to fine or ultrafine particles from either period failed to elicit significant lung or systemic effects. In contrast, mice exposed to ENCF-1 ultrafine PM developed significantly decreased cardiac function and greater post-ischemia-associated myocardial infarction. Finally, similar exposures to mouse lung slices induced comparable patterns of cytokine production; and these responses were significantly attenuated by PMB. The findings suggest that exposure to coarse PM collected during a peat fire causes greater lung inflammation in association with endotoxin and ROS, whereas the ultrafine PM preferentially affected cardiac responses. In addition, lung tissue slices were shown to be a predictive, alternative assay to assess pro-inflammatory effects of PM of differing size and composition. Importantly, these toxicological findings were consistent with the cardiopulmonary health effects noted in epidemiologic reports from exposed populations.

Cardiopulmonary toxicity of peat wildfire particulate matter and the predictive utility of precision cut lung slices

PubMed Central

2014-01-01

Background Emissions from a large peat fire in North Carolina in 2008 were associated with increased hospital admissions for asthma and the rate of heart failure in the exposed population. Peat fires often produce larger amounts of smoke and last longer than forest fires, however few studies have reported on their toxicity. Moreover, reliable alternatives to traditional animal toxicity testing are needed to reduce the number of animals required for hazard identification and risk assessments. Methods Size-fractionated particulate matter (PM; ultrafine, fine, and coarse) were obtained from the peat fire while smoldering (ENCF-1) or when nearly extinguished (ENCF-4). Extracted samples were analyzed for chemical constituents and endotoxin content. Female CD-1 mice were exposed via oropharyngeal aspiration to 100 μg/mouse, and assessed for relative changes in lung and systemic markers of injury and inflammation. At 24 h post-exposure, hearts were removed for ex vivo functional assessments and ischemic challenge. Lastly, 8 mm diameter lung slices from CD-1 mice were exposed (11 μg) ± co-treatment of PM with polymyxin B (PMB), an endotoxin-binding compound. Results On an equi-mass basis, coarse ENCF-1 PM had the highest endotoxin content and elicited the greatest pro-inflammatory responses in the mice including: increases in bronchoalveolar lavage fluid protein, cytokines (IL-6, TNF-α, and MIP-2), neutrophils and intracellular reactive oxygen species (ROS) production. Exposure to fine or ultrafine particles from either period failed to elicit significant lung or systemic effects. In contrast, mice exposed to ENCF-1 ultrafine PM developed significantly decreased cardiac function and greater post-ischemia-associated myocardial infarction. Finally, similar exposures to mouse lung slices induced comparable patterns of cytokine production; and these responses were significantly attenuated by PMB. Conclusions The findings suggest that exposure to coarse PM collected during a peat fire causes greater lung inflammation in association with endotoxin and ROS, whereas the ultrafine PM preferentially affected cardiac responses. In addition, lung tissue slices were shown to be a predictive, alternative assay to assess pro-inflammatory effects of PM of differing size and composition. Importantly, these toxicological findings were consistent with the cardiopulmonary health effects noted in epidemiologic reports from exposed populations. PMID:24934158

Radiocarbon ages of different fractions of peat on coastal lowland of Bohai Bay: marine influence?

NASA Astrophysics Data System (ADS)

Shang, Zhiwen; Wang, Fu; Fang, Jing; Li, Jianfen; Chen, Yongsheng; Jiang, Xingyu; Tian, Lizhu; Wang, Hong

2018-05-01

Peat in boreholes is the most important 14C dating material used for constructing age framework. 20 bulk peat samples were collected from five boreholes, the 14C ages of two fractions (organic sediment fraction and peat fraction) of the bulk peat samples were investigated by AMS-dating and which fraction is better to help construct an age framework for the boreholes were compared and discussed. The results indicated that the peat fraction give a good dating results sequence in the boreholes, compared with the corresponding organic sediment fraction. And the dating results of organic sediment fraction show 161-6 702 years older than corresponding peat fraction, which was caused by marine influence. Then, we suggest an experience formula as y=0.99x-466.5 by the correlation analysis for correcting the marine influenced organic sediment ages within the conventional ages between 4 000 to 9 000 yrs BP, and more study should be carried out for the AMS 14C dating of the bulk organic sediments.

Biochemical processes of oligotrophic peat deposits of Vasyugan Mire

NASA Astrophysics Data System (ADS)

Inisheva, L. I.; Sergeeva, M. A.

2009-04-01

The problem of peat and mire ecosystems functioning and their rational use is the main problem of biosphere study. This problem also refers to forecasting of biosphere changes results which are global and anthropogenic. According to many scientists' research the portion of mires in earth carbon balance is about 15% of world's stock. The aim of this study is to investigate biochemical processes in oligotrophic deposits in North-eastern part of Vasyugan Mire. The investigations were made on the territory of scientific-research ground (56˚ 03´ and 56˚ 57´ NL, 82˚ 22´ and 82˚ 42´ EL). It is situated between two rivers Bakchar and Iksa (in outskirts of the village Polynyanka, Bakchar region, Tomsk oblast). Evolution of investigated mire massif began with the domination of eutrophic phytocenosis - Filicinae, then sedge. Later transfer into oligotrophic phase was accompanied by formation of meter high-moor peat deposit. The age of three-meter peat deposit reaches four thousand years. Biochemical processes of carbon cycle cover the whole peat deposit, but the process activity and its direction in different layers are defined by genesis and duration of peat formation. So, the number of cellulose-fermenting aerobes in researched peat deposits ranges from 16.8 to 75.5 million CFU/g, and anaerobic bacteria from 9.6 to 48.6 million CFU/g. The high number of aerobes is characteristic for high water levels, organizing by raised bog peats. Their number decreases along the profile in 1.7 - 2 times. The number of microflora in peat deposit is defined by the position in the landscape profile (different geneses), by the depth, by hydrothermic conditions of years and individual months. But microflora activity shows along all depth of peat deposit. We found the same in the process of studying of micromycete complex structure. There was revealed either active component micromycete complex - mycelium, or inert one - spores in a meter layer of peat deposit. If mushrooms spores are observed in all deposit layers, mycelium of mushrooms deepens into the peat deposit (to 2 meters) within the limits of aerobic (meter) zone and only in particular months of dry years. The existence of seasonal dynamics of eukaryotic cells, and also capability of yeast and other groups of micromycetes for growth, testifies about vital activity of a number of eukaryotic cells at a depth of 2 meters. Researched peat deposits are biochemically active along the whole profile. But they are different in a microflora number of individual physiological groups either in items of the landscape, or in deposit depth. The largest quantity of aerobic cellulose-fermenting microorganisms is marked during dry years. Anaerobic cellulose-fermenting microorganisms dominate during wet years. The quantity of microbe biomass increases in bottom lifts of peat deposits. This fact testifies about viable condition of microbe complex at depth. The formation process of carbon dioxide in peat deposits of Vasyugan Mire actively occurs during dry years and is defined by hydrothermic conditions of a meter layer of peat deposit. The intensity of CO2 isolation for certain correlates with the temperature in horizon of 0 - 50 sm. and with bog waters level. The study of gas composition for the three years showed that the largest concentration of carbon dioxide in peat soils is marked along the whole profile during a dryer year (0.08 - 2.65 millimole/l), increasing other years' level in about 1.5 0 2 times. Emission of carbon dioxide in peat

How does conversion from peat swamp forest to oil palm plantation affect emissions of nitrous oxide from the soil? A case study in Jambi, Indonesia

NASA Astrophysics Data System (ADS)

Hartill, Jodie; Hergoualc'h, Kristell; Comeau, Louis-Pierre; Jo, Smith; Lou, Verchot

2017-04-01

Half of the peatlands across Peninsular Malaysia, Borneo and Sumatra are 'managed'. Conversion of peat swamp forest to workable oil palm plantation requires a drastic, potentially irreversible, change to the landscape, to which fertilizers are then routinely applied. A combination of these factors is now widely thought to increase soil nitrous oxide (N2O) emissions, although there is high uncertainty due to gaps in the knowledge, both regionally and nationally. Despite the widespread use of fertilizers in plantations on peats, studies observing their effects remain very limited. Therefore, there is a need for in situ studies to evaluate how environmental parameters (edaphic properties, climate, soil moisture and N availability indicators) influence soil emissions. This 18 month study was located in plots local to each other, representing the start, intermediate and end of the land conversion process; namely mixed peat swamp forest, drained and logged forest and industrial oil palm plantation. Spatial variability was taken into account by differentiating the hollows and hummocks in the mixed peat swamp forest, and the fertilized zone and the zone without fertilizer addition in the oil palm plantation. Gas samples were collected each month from static chambers at the same time as key environmental parameters were measured. Intensive sampling was performed during a 35 day period following two fertilizer applications, in which urea was applied to palms at rates of 0.5 and 1 kg urea palm-1. Soil N2O emissions (kg N ha-1 y-1 ± SE) were low overall, but they were greater in the oil palm plantation (0.8 ± 0.1) than in the mixed peat swamp forest (0.3 ± 0.0) and the drained/logged forest (0.2 ± 0.0). In the mixed peat swamp forest, monthly average fluxes of N2O (g N ha-1 d-1 ± SE) were similar in the hollows (0.6 ± 0.2) and the hummocks (0.3 ± 0.1), whereas in the oil palm plantation they were consistently higher in the zone without fertilizer (2.5 ± 0.4) than in the fertilized zone (0.5 ± 0.1), even after fertilizer application. In the fertilized zones, the N2O fluxes following the two fertilizer applications were 2.4 and 4.5 times higher respectively than fluxes observed in the absence of fertilizers. No change in emissions was observed in the neighboring unfertilized zone at the time of fertilizer application. Soil N2O emissions were related to changes in air and soil temperature in the mixed peat swamp forest, air temperature and water table depth in the drained and logged forest, and rainfall on the day of measurement in the oil palm plantation. This research confirms that peat forest conversion to oil palm plantation has negative consequences on the emissions of N2O. It also corroborates an increase in emission due to fertilizer application, with a magnitude comparable to the emission factor provided by the IPCC guidelines, but this is restricted to the limited area of fertilizer application.

Stocks and fluxes of carbon associated with land use change in Southeast Asian tropical peatlands: A review

NASA Astrophysics Data System (ADS)

Hergoualc'h, Kristell; Verchot, Louis V.

2011-06-01

The increasing and alarming trend of degradation and deforestation of tropical peat swamp forests may contribute greatly to climate change. Estimates of carbon (C) losses associated with land use change in tropical peatlands are needed. To assess these losses we examined C stocks and peat C fluxes in virgin peat swamp forests and tropical peatlands affected by six common types of land use. Phytomass C loss from the conversion of virgin peat swamp forest to logged forest, fire-damaged forest, mixed croplands and shrublands, rice field, oil palm plantation, and Acacia plantation were calculated using the stock difference method and estimated at 116.9 ± 39.8, 151.6 ± 36.0, 204.1 ± 28.6, 214.9 ± 28.4, 188.1 ± 29.8, and 191.7 ± 28.5 Mg C ha-1, respectively. Total C loss from uncontrolled fires ranged from 289.5 ± 68.1 Mg C ha-1 in rice fields to 436.2 ± 77.0 Mg C ha-1 in virgin peat swamp forest. We assessed the effects of land use change on C stocks in the peat by looking at how the change in vegetation cover altered the main C inputs (litterfall and root mortality) and outputs (heterotrophic respiration, CH4 flux, fires, and soluble and physical removal) before and after conversion. The difference between the soil input-output balances in the virgin peat swamp forest and in the oil palm plantation gave an estimate of peat C loss of 10.8 ± 3.5 Mg C ha-1 yr-1. Peat C loss from other land use conversions could not be assessed due to lack of data, principally on soil heterotrophic respiration rates. Over 25 years, the conversion of tropical virgin peat swamp forest into oil palm plantation represents a total C loss from both biomass and peat of 427.2 ± 90.7 Mg C ha-1 or 17.1 ± 3.6 Mg C ha-1 yr-1. In all situations, peat C loss contributed more than 63% to total C loss, demonstrating the urgent need in terms of the atmospheric greenhouse gas burden to protect tropical virgin peat swamp forests from land use change and fires.

Mobile geophysical study of peat deposits in Fuhrberger Field, Germany

NASA Astrophysics Data System (ADS)

Wunderlich, T.; Petersen, H.; Hagrey, S. A. al; Rabbel, W.

2012-04-01

In the water protection area of Fuhrberger Field, north of Hanover, geophysical techniques were applied to study the stakeholder problem of the source detection for nitrate accumulations in the ground water. We used our mobile multisensor platform to conduct measurements using Ground Penetrating Radar (GPR, 200 MHz antenna) and Electromagnetic Induction (EMI, EM31). This aims to study the subsurface occurrences of peat deposits (surplus of organic carbon) supposed to be a source of nitrate emissions due to the aeration and the drawdown of groundwater levels (e.g. by pumping, drainage etc.). Resulting EMI and GPR signals show high data quality. Measured apparent electrical conductivity shows very low values (<10 mS/m) due to the mainly sandy subsurface. For this medium, both methods are expected to penetrate down to 3-5 m depth. GPR radargrams, time slices of GPR reflection energy and EMI apparent electrical conductivities are plotted on aerial photographs and compared to each other's and with vegetation intensity. We could separate areas characterized by low reflection energy and high conductivity, and vice versa. Briefly, organic rich sediments such as peats are assumed to have a relative high conductivity and thus low GPR reflectivity. Some areas of local conductivity increase correspond to a deep reflection interface (as seen in the radargrams), which even vanishes due to the high attenuation caused by the high conductivity. This implies that the upper layer is more conductive than the lower layer. Several local areas with these characteristics are found at the study sites. We recommend shallow drillings at representative points to deliver the necessary confirmation with ground truth information. Acknowledgments: iSOIL (Interactions between soil related sciences - Linking geophysics, soil science and digital soil mapping) is a Collaborative Project (Grant Agreement number 211386) co-funded by the Research DG of the European Commission within the RTD activities of the FP7 Thematic Priority Environment.

Bioaccumulation of petroleum hydrocarbons in arctic amphipods in the oil development area of the Alaskan Beaufort Sea.

PubMed

Neff, Jerry M; Durell, Gregory S

2012-04-01

An objective of a multiyear monitoring program, sponsored by the US Department of the Interior, Bureau of Ocean Energy Management was to examine temporal and spatial changes in chemical and biological characteristics of the Arctic marine environment resulting from offshore oil exploration and development activities in the development area of the Alaskan Beaufort Sea. To determine if petroleum hydrocarbons from offshore oil operations are entering the Beaufort Sea food web, we measured concentrations of hydrocarbons in tissues of amphipods, Anonyx nugax, sediments, Northstar crude oil, and coastal peat, collected between 1999 and 2006 throughout the development area. Mean concentrations of polycyclic aromatic hydrocarbons (PAH), saturated hydrocarbons (SHC), and sterane and triterpane petroleum biomarkers (StTr) were not significantly different in amphipods near the Northstar oil production facility, before and after it came on line in 2001, and in amphipods from elsewhere in the study area. Forensic analysis of the profiles (relative composition and concentrations) of the 3 hydrocarbon classes revealed that hydrocarbon compositions were different in amphipods, surface sediments where the amphipods were collected, Northstar crude oil, and peat from the deltas of 4 North Slope rivers. Amphipods and sediments contained a mixture of petrogenic, pyrogenic, and biogenic PAH. The SHC in amphipods were dominated by pristane derived from zooplankton, indicating that the SHC were primarily from the amphipod diet of zooplankton detritus. The petroleum biomarker StTr profiles did not resemble those in Northstar crude oil. The forensic analysis revealed that hydrocarbons in amphipod tissues were not from oil production at Northstar. Hydrocarbons in amphipod tissues were primarily from their diet and from river runoff and coastal erosion of natural diagenic and fossil terrestrial materials, including seep oils, kerogens, and peat. Offshore oil and gas exploration and development do not appear to be causing an increase in petroleum hydrocarbon contamination of the Beaufort Sea food web. Copyright © 2011 SETAC.

Genesis of peat-bog soils in the northern taiga spruce forests of the Kola Peninsula

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nikonov, V.V.

1981-01-01

The characteristics of soil formation processes in the Peat-Bog soils of waterlogged spruce phytocenoses on the Kola Peninsula are investigated. It is found that the ash composition of the peat layer is determined primarily by the composition of the buried plant residues. The effect of the chemical composition of water feeding the peat bogs is determined. (Refs. 7).

Soil carbon dioxide emissions from a rubber plantation on tropical peat.

PubMed

Wakhid, Nur; Hirano, Takashi; Okimoto, Yosuke; Nurzakiah, Siti; Nursyamsi, Dedi

2017-03-01

Land-use change in tropical peatland potentially results in a large amount of carbon dioxide (CO 2 ) emissions owing to drainage, which lowers groundwater level (GWL) and consequently enhances oxidative peat decomposition. However, field information on carbon balance is lacking for rubber plantations, which are expanding into Indonesia's peatlands. To assess soil CO 2 emissions from an eight-year-old rubber plantation established on peat after compaction, soil CO 2 efflux was measured monthly using a closed chamber system from December 2014 to December 2015, in which a strong El Niño event occurred, and consequently GWL lowered deeply. Total soil respiration (SR) and oxidative peat decomposition (PD) were separately quantified by trenching. In addition, peat surface elevation was measured to determine annual subsidence along with GWL. With GWL, SR showed a negative logarithmic relationship (p<0.01), whereas PD showed a strong negative linearity (p<0.001). Using the significant relationships, annual SR and PD were calculated from hourly GWL data to be 3293±1039 and 1408±214gCm -2 yr -1 (mean±1 standard deviation), respectively. PD accounted for 43% of SR on an annual basis. SR showed no significant difference between near and far positions from rubber trees (p>0.05). Peat surface elevation varied seasonally in almost parallel with GWL. After correcting for GWL difference, annual total subsidence was determined at 5.64±3.20 and 5.96±0.43cmyr -1 outside and inside the trenching, respectively. Annual subsidence only through peat oxidation that was calculated from the annual PD, peat bulk density and peat carbon content was 1.50cmyr -1 . As a result, oxidative peat decomposition accounted for 25% of total subsidence (5.96cmyr -1 ) on average on an annual basis. The contribution of peat oxidation was lower than those of previous studies probably because of compaction through land preparation. Copyright © 2017 Elsevier B.V. All rights reserved.

Phosphorus mobilization in rewetted fens: the effect of altered peat properties and implications for their restoration.

PubMed

Zak, Dominik; Wagner, Carola; Payer, Brian; Augustin, Jürgen; Gelbrecht, Jörg

2010-07-01

Rewetting of drained fens is necessary to stop further soil degradation and to reestablish important ecological functions. However, substantial changes of peat characteristics in the upper soil layers, due to drainage and land use, could counteract their recovery as nutrient-poor systems for an unknown period. We assessed the importance of altered peat properties, such as the degree of peat decomposition and the amount of redox-sensitive phosphorus (P) compounds, for P mobilization in different degraded fens. An experimental design involving 63 intact peat cores from fens with varying drainage and land-use histories was developed to quantify the mobilization of P, as well as that of iron (Fe), ammonium, carbon dioxide, and methane, all indicators of organic-matter decomposition and/or P-releasing processes. We found that net P release rates in peat cores with highly decomposed peat (range: 0.1-52.3 mg P x m(-2) x d(-1)) were significantly correlated to the amount of P bound to redox-sensitive compounds and the molar Fe:P as well as Al:P ratios of peat. We conclude that the following general rules apply for P mobilization in rewetted fens: (1) elevated levels of P release rates and P concentrations in pore water up to three orders of magnitude larger than under natural reference conditions can only be expected for rewetted fens whose surface soil layers consist of highly decomposed peat; (2) peat characteristics, such as the amount of P bound to redox-sensitive Fe(III) compounds (positive correlation) and molar ratios of Fe:P or Al:P (negative correlations), explain the high range of P release rates; and (3) a critical P export to adjacent lakes or rivers can only be expected if molar Fe:P ratios of highly decomposed peat are less than 10.

The new European Competence Centre for Moor and Climate - A European initiative for practical peat bog and climate protection

NASA Astrophysics Data System (ADS)

Smidt, Geerd; Tänzer, Detlef

2013-04-01

The new European Competence Centre for Moor and Climate (EFMK) is an initiative by different local communities, environmental protection NGOs, agricultural services, and partners from the peat and other industries in Lower Saxony (Germany). The Centre aims to integrate practical peat bog conservation with a focus on green house gas emission after drainage and after water logging activities. Together with our partners we want to break new ground to protect the remaining bogs in the region. Sphagnum mosses will be produced in paludiculture on-site in cooperation with the local peat industry to provide economic and ecologic alternatives for peat products used in horticulture business. Land-use changes are needed in the region and will be stimulated in cooperation with agricultural services via compensation money transfers from environmental protection funds. On a global scale the ideas of Carbon Credit System have to be discussed to protect the peat bogs for climate protection issues. Environmental education is an important pillar of the EFMK. The local society is invited to explore the unique ecosystem and to participate in peat bog protection activities. Future generations will be taught to understand that the health of our peat bogs is interrelated with the health of the local and global climate. Besides extracurricular classes for schools the centre will provide infrastructure for Master and PhD students, as well for senior researchers for applied research in the surrounding moor. International partners in the scientific and practical fields of peat bog ecology, renaturation, green house gas emissions from peat bogs, and environmental policy are invited to participate in the European Competence Center for Moor and Climate.

Identification of runoff formation with two dyes in a mid-latitude mountain headwater

NASA Astrophysics Data System (ADS)

Vlcek, Lukas; Schneider, Philipp; Falatkova, Kristyna

2017-04-01

There have been numerous studies on subsurface flow in peat bog areas, as both water scarcity and floods have led to increased attention to this specific environment and its role within the hydrological cycle. In contrast, this experimental study identifies runoff formation at two opposite hillslopes in a peaty mountain headwater; a slope with organic soils (Peat / Histosol) and shallow groundwater ( 0.5 m below surface) complemented by a slope with mineral soils (Podzol) and no detectable groundwater within 2 m below surface. Differences in infiltration, percolation, and preferential flowpaths between both hillslopes could be identified by sprinkling experiments with two dyes - Brilliant Blue FCF and Fluorescein. By excavating dye-stained soil profiles parallel ("lateral") and perpendicular ("frontal") to the slopes' gradients - both within and downstream of the sprinkling plots - dye stained flow patterns in the soil could be clearly identified. The results show that biomat flow occurred at both hillslopes. The dye solutions infiltrated into the soil and continued either as lateral subsurface pipeflow (SSF), in the case of the Peat Bog, or percolated vertically towards the bedrock in the case of the Podzol. The study provides evidence that biomat flow (BMF) - shallow, lateral preferential flowpaths along decomposed tree roots or logs - is a major runoff formation process at the Peat Bog hillslope and in the adjacent riparian zone. This lateral flow through the organic soil hillslope (Peat Bog) towards the stream occurred mainly as shallow subsurface flow in organic layers above the groundwater level (BMF and SSF), but water partly percolates to the shallow groundwater via vertical macropores as well . In contrast, the mineral soil hillslope (Podzol) was mostly dominated by vertical percolation. Lateral flow occurred only on short distances in the organic topsoil as biomat flow (BMF). The sorptive tracer Brilliant Blue FCF successfully stained flowpaths in the soil at both hillslopes, whereas the identification of soil staining patterns by the relatively conservative tracer Fluorescein was limited on organic soil profiles.

Transition from a warm and dry to a cold and wet climate in NE China across the Holocene

NASA Astrophysics Data System (ADS)

Zheng, Yanhong; Pancost, Richard D.; Naafs, B. David A.; Li, Qiyuan; Liu, Zhao; Yang, Huan

2018-07-01

Northeast (NE) China lies in the northernmost part of the East Asian Summer monsoon (EASM) region. Although a series of Holocene climatic records have been obtained from lakes and peats in this region, the Holocene hydrological history and its controls remain unclear. More specifically, it is currently debated whether NE China experienced a dry or wet climate during the early Holocene. Here we reconstruct changes in mean annual air temperature and peat soil moisture across the last ∼13,000 year BP using samples from the Gushantun and Hani peat, located in NE China. Our approach is based on the distribution of bacterial branched glycerol dialkyl glycerol tetraethers (brGDGTs) and the abundance of the archaeal isoprenoidal (iso)GDGT crenarchaeol. Using the recently developed peat-specific MAATpeat temperature calibration we find that NE China experienced a relatively warm early Holocene (∼5-7 °C warmer than today), followed by a cooling trend towards modern-day values during the mid- and late Holocene. Moreover, crenarchaeol concentrations, brGDGT-based pH values, and the distribution of 6-methyl brGDGTs, all indicate an increase in soil moisture content from the early to late Holocene in both peats, which is largely consistent with other data from NE China. This trend towards increasing soil moisture/wetter conditions across the Holocene in NE China records contrasts with the trends observed in other parts of the EASM region, which exhibit an early and/or mid-Holocene moisture/precipitation maximum. However, the Holocene soil moisture variations and temperature-moisture relationships (warm-dry and cold-wet) observed in NE China are similar to those observed in the core area of arid central Asia which is dominated by the westerlies. We therefore propose that an increase in the intensity of the westerlies across the Holocene, driven by increasing winter insolation, expanding Arctic sea ice extent and the enhanced Okhotsk High, caused an increase in moisture during the late Holocene in NE China.

Exploring 222Rn as a tool for tracing groundwater inflows from eskers and moraines into slope peatlands of the Amos region of Quebec, Canada.

PubMed

Berthot, Laureline; Pinti, Daniele L; Larocque, Marie; Gagné, Sylvain; Ferlatte, Miryane; Cloutier, Vincent

2016-11-01

Peatlands can play an important role in the hydrological dynamics of a watershed. However, interactions between groundwater and peat water remain poorly understood. Here, we present results of an exploratory study destined to test radon ( 222 Rn) as a potential tracer of groundwater inflows from fluvioglacial landform aquifers to slope peatlands in the Amos region of Quebec, Canada. 222 Rn occurs in groundwater but is expected to be absent from peat water because of its rapid degassing to the atmosphere. Any 222 Rn activity detected in peat water should therefore derive from groundwater inflow. 222 Rn activity was measured in groundwater from municipal, domestic wells and newly drilled and instrumented piezometers from the Saint-Mathieu-Berry and Barraute eskers (n = 9), from the Harricana Moraine (n = 4), and from the fractured bedrock (n = 3). Forty measurements of 222 Rn activity were made from piezometers installed in five slope peatlands, along six transects oriented perpendicular to the fluvioglacial deposits. The relationship between 222 Rn and total dissolved solids (TDS) measured in water from the mineral deposits underlying the peat layer suggests that 222 Rn is introduced by lateral inflow from eskers and moraine together with salinity. This input is then diluted by peat water, depleted in both TDS and 222 Rn. The fact that a relationship between TDS and 222 Rn is visible calls for a continuous inflow of groundwater from lateral eskers/moraines, being 222 Rn rapidly removed from the system by radioactive decay. Although more research is required to improve the sampling and tracing techniques, this work shows the potential of 222 Rn tracer to identify groundwater inflow areas from granular aquifers found in eskers and moraines to slope peatlands. Copyright © 2016 Elsevier Ltd. All rights reserved.

In situ fluidization for peat bed rupture, and preliminary economic analysis.

PubMed

Niven, R K; Khalili, N

2002-11-01

This study concerns in situ fluidization (ISF), a new remediation method with potential application to the remediation of NAPL and heavy metal contaminants, by their release from the fluidized zone generated by a water jet. The present study examines the effect of ISF on layers of peat, of significance owing to its role as an important NAPL and metal contaminant trap. Once trapped, such contaminants are not readily accessible by most remedial methods, due to the low permeability and diffusivity of the peat. A simple tank experiment is used to demonstrate rupture of a peat layer by ISF, with removal of the peat as elutriated fines and segregated peat chunks. The application of ISF in the field is then examined by three field trials in uncontaminated sands, in both saturated and unsaturated conditions. Fluidized depths of up to 1.9 m in the saturated zone (with refusal on a peat layer) and 2.5 m in the unsaturated zone (no refusal) were attained, using a 1.9-m-long, 50 mm diameter jet operated at 5-13 1 s(-1). Pulses of dark turbidity and shell fragments in the effluent indicated the rupture of peat and shelly layers. The experiments demonstrate the hydraulic viability of ISF in the field, and its ability to remove peat-based contaminants. The issues of appropriate jet design and water generation during ISF are discussed, followed by a preliminary economic analysis of ISF relative to existing remediation methods.

Scheduling Accessory Assists Patients with Cognitive Disorders

NASA Technical Reports Server (NTRS)

2007-01-01

Recom Technologies Inc. received initial funding from NASA to research the commercial potential of an artificially intelligent planning reaction model to serve as a tool to help individuals suffering from various forms and levels of brain impairment. In 1993, the chief of the Artificial Intelligence Research Branch at Ames Research Center suggested collaborative research with Santa Clara Valley Medical Center. This partnership led to further development of the technology and funding to support clinical research from the U.S. Department of Education's National Institute on Disability and Rehabilitation Research. In 1996, Attention Control Systems Inc. was founded to market the finished device, called the Planning and Execution Assistant and Trainer (PEAT). PEAT is a pocket-sized PDA-like device with a graphical display, touchscreen controls, an electronic calendar, an address book, and a built-in phone, that cues users to start or stop scheduled activities, monitors their progress, and adjusts schedules as necessary in response to delays or calendar changes. It uses an automatic planning model developed for NASA to adjust daily plans when a situation changes. PEAT is sold as a complete system that includes software, hardware, documentation, and technical support. In addition to the flagship Pocket PEAT device, there is PEAT Phone, PC PEAT, and PEAT Link. Clinical studies of PEAT continue at Santa Clara Valley Medical Center

Heat transport in the Red Lake Bog, Glacial Lake Agassiz Peatlands

USGS Publications Warehouse

McKenzie, J.M.; Siegel, D.I.; Rosenberry, D.O.; Glaser, P.H.; Voss, C.I.

2007-01-01

We report the results of an investigation on the processes controlling heat transport in peat under a large bog in the Glacial Lake Agassiz Peatlands. For 2 years, starting in July 1998, we recorded temperature at 12 depth intervals from 0 to 400 cm within a vertical peat profile at the crest of the bog at sub-daily intervals. We also recorded air temperature 1 m above the peat surface. We calculate a peat thermal conductivity of 0.5 W m-1 ??C-1 and model vertical heat transport through the peat using the SUTRA model. The model was calibrated to the first year of data, and then evaluated against the second year of collected heat data. The model results suggest that advective pore-water flow is not necessary to transport heat within the peat profile and most of the heat is transferred by thermal conduction alone in these waterlogged soils. In the spring season, a zero-curtain effect controls the transport of heat through shallow depths of the peat. Changes in local climate and the resulting changes in thermal transport still may cause non-linear feedbacks in methane emissions related to the generation of methane deeper within the peat profile as regional temperatures increase. Copyright ?? 2006 John Wiley & Sons, Ltd.

Logged peat swamp forest supports greater macrofungal biodiversity than large-scale oil palm plantations and smallholdings.

PubMed

Shuhada, Siti Noor; Salim, Sabiha; Nobilly, Frisco; Zubaid, Akbar; Azhar, Badrul

2017-09-01

Intensive land expansion of commercial oil palm agricultural lands results in reducing the size of peat swamp forests, particularly in Southeast Asia. The effect of this land conversion on macrofungal biodiversity is, however, understudied. We quantified macrofungal biodiversity by identifying mushroom sporocarps throughout four different habitats; logged peat swamp forest, large-scale oil palm plantation, monoculture, and polyculture smallholdings. We recorded a total of 757 clusters of macrofungi belonging to 127 morphospecies and found that substrates for growing macrofungi were abundant in peat swamp forest; hence, morphospecies richness and macrofungal clusters were significantly greater in logged peat swamp forest than converted oil palm agriculture lands. Environmental factors that influence macrofungi in logged peat swamp forests such as air temperature, humidity, wind speed, soil pH, and soil moisture were different from those in oil palm plantations and smallholdings. We conclude that peat swamp forests are irreplaceable with respect to macrofungal biodiversity. They host much greater macrofungal biodiversity than any of the oil palm agricultural lands. It is imperative that further expansion of oil palm plantation into remaining peat swamp forests should be prohibited in palm oil producing countries. These results imply that macrofungal distribution reflects changes in microclimate between habitats and reduced macrofungal biodiversity may adversely affect decomposition in human-modified landscapes.

The Characteristics of Electrical and Physical Properties of Peat Soil in Rasau Village, West Kalimantan

NASA Astrophysics Data System (ADS)

Aminudin, A.; Hasanah, T. R.; Iryati, M.

2018-05-01

The Electrical and physical properties can be used as indicators for measuring soil conditions. One of the methods developed in agricultural systems to obtain information on soil conditions is through measuring of electrical conductivity. Peat soil is one of the natural resources that exist in Indonesia. This study aims to determine the characteristics of peat soil in Rasau village, West Kalimantan. This research was conducted by the properties of electrical conductivity and water content using 5TE Water Contents and EC Sensor equipment, but also to know the change of physical nature of peat soil covering peat soil and peat type. The results showed that the electrical conductivity value of 1-4 samples was 0.02 -0.29 dS/m and the volume water content value (VWC) was 0.255-0.548 m3/m3 and the physical characteristics obtained were peat colour brown to dark brown that allegedly the soil still has a very high content of organic material derived from weathering plants and there are discovery of wood chips, wood powder and leaf powder on the ground. Knowing the information is expected to identify the land needs to be developed to be considered for future peat soil utilization.

Greenhouse gas balance of blanket peat bog restoration from forestry in the Flow Country, Scotland

NASA Astrophysics Data System (ADS)

Hermans, Renée; Subke, Jens-Arne; Cowie, Neil; Arn Teh, Yit; Andersen, Roxane

2017-04-01

The Flow country in the far north of Scotland has the largest expanse of blanket peat bog in Europe. With peat depths of up to several metres, this area represents a significant carbon store. Large parts of the Flows were drained for afforestation with non-native conifers during the 1980s, which resulted in considerable damage to the peat, leading to significant carbon loss. To restore the peatland, the Royal Society for the Protection of Birds (RSPB) started in the late 1990s to fell trees and block drains. Over 2200 ha of forestry are felled. The main objective of this study is to measure the impact of forest removal on the budget of three main greenhouse gases, CO2, CH4 and N2O. Local variations in fluxes were measured using dark closed chambers. In order to capture abiotic conditions likely to determine microbial activity and therefor CO2, CH4 and N2O production, I record water table depth as well as soil moisture and soil temperature (both measured at 5 and 20 cm deep). These measurements are done in near pristine bog (control plot), in forest (control plot), in recently felled areas and in areas that were felled up to 19 years ago, creating a chronosequence to follow the effects of restoration. Results indicate only small differences in annual CO2 flux to the atmosphere between sites, with only the 19-year old restored site showing higher fluxes than forest control plots. However some seasonal differences in CO2 flux between land cover are evident. CH4 fluxes from forest are significantly lower than from bog and the site restored 17 years ago, and N2O fluxes are very low in all sites with no significant differences between sites. Sites where forests were removed recently (< 1 year previously) show a high degree of variability in CH4 fluxes, indicating potential flux spikes from disturbance. There is a positive correlation between soil temperature and CO2 and CH4 flux. Soil moisture varies a lot between bog, restored sites and forest, however there does not seem to be a direct correlation between soil moisture at the surface and CO2 and CH4 fluxes. Peatlands store big amounts of carbon, therefore there is a high level of importance to quantify the impact of various restoration techniques used.

On-line sulfur isotope analysis of organic material by direct combustion: Preliminary results and potential applications

USGS Publications Warehouse

Kester, C.L.; Rye, R.O.; Johnson, C.A.; Schwartz, C.H.; Holmes, C.H.

2001-01-01

Sulfur isotopes have received little attention in ecology studies because plant and animal materials typically have low sulfur concentrations (< 1 wt.%) necessitating labor-intensive chemical extraction prior to analysis. To address the potential of direct combustion of organic material in an elemental analyzer coupled with a mass spectrometer, we compared results obtained by direct combustion to results obtained by sulfur extraction with Eschka's mixture. Direct combustion of peat and animal tissue gave reproducibility of better than 0.5??? and on average, values are 0.8??? higher than values obtained by Eschka extraction. Successful direct combustion of organic material appears to be a function of sample matrix and sulfur concentration. Initial results indicate that direct combustion provides fast, reliable results with minimal preparation. Pilot studies underway include defining bear diets and examining fluctuations between freshwater and brackish water in coastal environments.

Peat drainage conditions assessment in Scotland

NASA Astrophysics Data System (ADS)

Poggio, Laura; Artz, Rebekka; Donaldson-Selby, Gillian; Aitkenhead, Matt; Donnelly, David; Gimona, Alessandro

2017-04-01

Large areas of Scotland are covered in peat, providing an important sink of carbon but also a notable source of emission where peatlands are not in good condition. However, despite data from designated sites that peat degradation is common, a detailed spatial assessment of the condition of most peatlands across the whole of Scotland is missing. An assessment of peatland drainage was carried out at >600 random sampling locations with an expert-based estimation of presence or absence of drainage ditches within a 500 metre block using 25 cm resolution aerial imagery. The resulting dataset was modelled using a scorpan-kriging approach, in particular using Generalised Additive Models for the description of the trend. Remote sensing images from different sensors (i.e. MODIS, Landsat and Sentinel 1 and 2) were used. In particular we used indices describing vegetation greenness (Enhanced Vegetation Index), water availability (Normalised Water Difference index), Land Surface Temperature and vegetation productivity. When considering MODIS indices we used time series and phenological summaries. The model provides also uncertainty of the estimations. The derived dataset can then be used in the decision making process for the selection of sites for restoration, emissions estimation and accounting.

Multiple sources for late-Holocene tsunamis at Discovery Bay, Washington State, USA

USGS Publications Warehouse

Williams, H.F.L.; Hutchinson, I.; Nelson, A.R.

2005-01-01

Nine muddy sand beds interrupt a 2500-yr-old sequence of peat deposits beneath a tidal marsh at the head of Discovery Bay on the south shore of the Strait of Juan de Fuca, Washington. An inferred tsunami origin for the sand beds is assessed by means of six criteria. Although all the sand beds contain marine diatoms and almost all the beds display internal stratification, the areal extent of the oldest beds is too limited to confirm their origin as tsunami deposits. The ages of four beds overlap with known late-Holocene tsunamis generated by plate-boundary earthquakes at the Cascadia subduction zone. Diatom assemblages in peat deposits bracketing these four beds do not indicate concurrent change in elevation at Discovery Bay. Diatoms in the peat bracketing a tsunami bed deposited about 1000 cal. yr BP indicate a few decimeters of submergence, suggesting deformation on a nearby upper-plate fault. Other beds may mark tsunamis caused by more distant upper-plate earthquakes or local submarine landslides triggered by earthquake shaking. Tsunamis from both subduction zone and upper-plate sources pose a significant hazard to shoreline areas in this region.

An Assessment of macro-scale in situ Raman and ultraviolet-induced fluorescence spectroscopy for rapid characterization of frozen peat and ground ice

NASA Astrophysics Data System (ADS)

Laing, Janelle R.; Robichaud, Hailey C.; Cloutis, Edward A.

2016-04-01

The search for life on other planets is an active area of research. Many of the likeliest planetary bodies, such as Europa, Enceladus, and Mars are characterized by cold surface environments and ice-rich terrains. Both Raman and ultraviolet-induced fluorescence (UIF) spectroscopies have been proposed as promising tools for the detection of various kinds of bioindicators in these environments. We examined whether macro-scale Raman and UIF spectroscopy could be applied to the analysis of unprocessed terrestrial frozen peat and clear ground ice samples for detection of bioindicators. It was found that this approach did not provide unambiguous detection of bioindicators, likely for a number of reasons, particularly due to strong broadband induced fluorescence. Other contributing factors may include degradation of organic matter in frozen peat to the point that compound-specific emitted fluorescence or Raman peaks were not resolvable. Our study does not downgrade the utility of either UIF or Raman spectroscopy for astrobiological investigations (which has been demonstrated in previous studies), but does suggest that the choice of instrumentation, operational conditions and sample preparation are important factors in ensuring the success of these techniques.

Influence of Biodegradation on the Organic Compounds Composition of Peat.

NASA Astrophysics Data System (ADS)

Serebrennikova, Olga; Svarovskaya, Lidiya; Duchko, Maria; Strelnikova, Evgeniya; Russkikh, Irina

2016-06-01

Largest wetland systems are situated on the territory of the Tomsk region. They are characterized by the high content of organic matter (OM), which undergoes transformation as a result of physical, chemical and biological processes. The composition of peat OM is determined by the nature of initial peat-forming plants, their transformation products and bacteria. An experiment in stimulated microbial impact was carried out for estimating the influence of biodegradation on the composition of peat lipids. The composition of the functional groups in the bacterial biomass, initial peat and peat after biodegradation was determined by IR-spectroscopy using the spectrometer NICOLET 5700. The IR spectra of peat and bacteria organic matter are characterized by the presence of absorption bands in ranges: 3400-3200 cm-1, which refers to the stretching vibrations of OH-group of carboxylic acids and various types of hydrogen bonds; 1738-1671 cm-1 - characteristic stretching vibrations of the C = O group of carboxylic acids and ketones; 1262 cm-1 - stretching vibrations of C-O of carboxylic acids. Group and individual composition of organic compounds in studied samples was determined by gas chromatography-mass-spectrometry.

The peats of Costa Rica

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thayer, G.R.; Williamson, K.D. Jr.; Ramirez, O.

The authors compare the competitive position of peat for energy with coal, oil, and cogenerative systems in gasifiers and solid-fuel boilers. They also explore the possibility for peat use in industry. To identify the major factors, they analyze costs using a Los Alamos levelized cost code, and they study parametric costs, comparing peat production in constant dollars with interest rates and return on investment. They consider costs of processing plant construction, sizes and kinds of boilers, retrofitting, peat drying, and mining methods. They examine mining requirements for Moin, Changuinola, and El Cairo and review wet mining and dewatering methods. Peatmore » can, indeed, be competitive with other energy sources, but this depends on the ratio of fuel costs to boiler costs. This ratio is nearly constant in comparison with cogeneration in a steam-only production system. For grate boilers using Costa Rican high-ash peat, and for small nonautomatic boilers now used in Costa Rica, the authors recommend combustion tests. An appendix contains a preliminary mining plan and cost estimate for the El Cairo peat deposit. 8 refs., 43 figs., 19 tabs.« less

Flow path oscillations in transient ground-water simulations of large peatland systems

USGS Publications Warehouse

Reeve, A.S.; Evensen, R.; Glaser, P.H.; Siegel, D.I.; Rosenberry, D.

2006-01-01

Transient numerical simulations of the Glacial Lake Agassiz Peatland near the Red Lakes in Northern Minnesota were constructed to evaluate observed reversals in vertical ground-water flow. Seasonal weather changes were introduced to a ground-water flow model by varying evapotranspiration and recharge over time. Vertical hydraulic reversals, driven by changes in recharge and evapotranspiration were produced in the simulated peat layer. These simulations indicate that the high specific storage associated with the peat is an important control on hydraulic reversals. Seasonally driven vertical flow is on the order of centimeters in the deep peat, suggesting that seasonal vertical advective fluxes are not significant and that ground-water flow into the deep peat likely occurs on decadal or longer time scales. Particles tracked within the ground-water flow model oscillate over time, suggesting that seasonal flow reversals will enhance vertical mixing in the peat column. The amplitude of flow path oscillations increased with increasing peat storativity, with amplitudes of about 5 cm occurring when peat specific storativity was set to about 0.05 m-1. ?? 2005 Elsevier B.V. All rights reserved.

n-Alkane distributions as indicators of novel ecosystem development in western boreal forest soils

NASA Astrophysics Data System (ADS)

Norris, Charlotte; Dungait, Jennifer; Quideau, Sylvie

2013-04-01

Novel ecosystem development is occurring within the western boreal forest of Canada due to land reclamation following surface mining in the Athabasca Oil Sands Region. Sphagnum peat is the primary organic matter amendment used to reconstruct soils in the novel ecosystems. We hypothesised that ecosystem recovery would be indicated by an increasing similarity in the biomolecular characteristics of novel reconstructed soil organic matter (SOM) derived from peat to those of natural boreal ecosystems. In this study, we evaluated the use of the homologous series of very long chain (>C20) n-alkanes with odd-over-even predominance as biomarker signatures to monitor the re-establishment of boreal forests on reconstructed soils. The lipids were extracted from dominant vegetation inputs and SOM from a series of natural and novel ecosystem reference plots. We observed unique very long n-alkane signatures of the source vegetation, e.g. Sphagnum sp. was dominated by C31 and aspen (Populus tremuloides Michx.) leaves by C25. Greater concentrations of very long chain n-alkanes were extracted from natural than novel ecosystem SOM (p<0.01), and their distribution differed between the two systems (p<0.001) and reflected the dominant vegetation input. Our results indicate that further research is required to clarify the influence of vegetation or disturbance on the signature of very long chain n-alkanes in SOM; however, the use of n-alkanes as biomarkers of ecosystem development is a promising method.

Colloid-facilitated metal transport in peat filters.

PubMed

Kalmykova, Yuliya; Rauch, Sebastien; Strömvall, Ann-Margret; Morrison, Greg; Stolpe, Björn; Hasselliöv, Martin

2010-06-01

The effect of colloids on metal retention in peat columns was studied, with the focus on colloids from two sources-organic matter leached from peat, and introduced organic and hydrous ferric oxide (HFO) colloids. A significant fraction of metals was found to be associated with peat-produced organic colloids; however the concentrations of organic colloids leached are low (trace concentrations) and temporal and have a limited effect on the efficiency of peat filters. In contrast, the presence of organic and HFO colloids in the input water causes a significant decrease in the performance of peat filters. Organic colloids were identified as the main vector of cadmium, copper, nickel, and zinc, while lead is transported by both organic and HFO colloids. The colloidal distribution of metals obtained in this study has important implications for the mobility of trace metals in porous media. The occurrence of colloids in the input waters and their characteristics must be considered when designing water treatment facilities.

The history of seabird colonies and the North Water ecosystem: Contributions from palaeoecological and archaeological evidence.

PubMed

Davidson, Thomas A; Wetterich, Sebastian; Johansen, Kasper L; Grønnow, Bjarne; Windirsch, Torben; Jeppesen, Erik; Syväranta, Jari; Olsen, Jesper; González-Bergonzoni, Ivan; Strunk, Astrid; Larsen, Nicolaj K; Meyer, Hanno; Søndergaard, Jens; Dietz, Rune; Eulears, Igor; Mosbech, Anders

2018-04-01

The North Water (NOW) polynya is one of the most productive marine areas of the Arctic and an important breeding area for millions of seabirds. There is, however, little information on the dynamics of the polynya or the bird populations over the long term. Here, we used sediment archives from a lake and peat deposits along the Greenland coast of the NOW polynya to track long-term patterns in the dynamics of the seabird populations. Radiocarbon dates show that the thick-billed murre (Uria lomvia) and the common eider (Somateria mollissima) have been present for at least 5500 cal. years. The first recorded arrival of the little auk (Alle alle) was around 4400 cal. years BP at Annikitsoq, with arrival at Qeqertaq (Salve Ø) colony dated to 3600 cal. years BP. Concentrations of cadmium and phosphorus (both abundant in little auk guano) in the lake and peat cores suggest that there was a period of large variation in bird numbers between 2500 and 1500 cal. years BP. The little auk arrival times show a strong accord with past periods of colder climate and with some aspects of human settlement in the area.

The effects of engineering fabric in street pavement on low bearing capacity soil in New Orleans : executive summary.

DOT National Transportation Integrated Search

1985-07-01

Subsurface soil in the New Orleans area is generally composed of peat and clay. The low bearing capacity of the soft natural soil has caused early deterioration of asphaltic concrete pavements which typically fail prior to carrying their designed loa...

N cycling in SPRUCE (Spruce Peatlands Response Under Climatic and Environmental Changes)

EPA Science Inventory

Peatlands located in boreal regions make up a third of global wetland area and are expected to have the highest temperature increases in response to climate change. As climate warms, we expect peat decomposition may accelerate, altering the cycling of nitrogen. Alterations in th...

Does boiling affect the bioaccessibility of selenium from cabbage?

PubMed

Funes-Collado, Virginia; Rubio, Roser; López-Sánchez, J Fermín

2015-08-15

The bioaccessible selenium species from cabbage were studied using an in vitro physiologically-based extraction test (PBET) which establishes conditions that simulate the gastric and gastrointestinal phases of human digestion. Samples of cabbage (Brassica oleracea) grown in peat fortified with different concentrations of Se(IV) and Se(VI) were analysed, and several enzymes (pepsin, pancreatin and amylase) were used in the PBET. The effect of boiling before extraction was also assayed. Selenium speciation in the PBET extracts was determined using anionic exchange and LC-ICP/MS. The selenocompounds in the extracts were Se(IV), SeMet and, mostly, Se(VI) species. The results show that the activity of the enzymes increased the concentration of the selenocompounds slightly, although the use of amylase had no effect on the results. The PBET showed the concentration of inorganic selenium in the extracts from boiled cabbage decreased as much as 4-fold while the release of SeMet and its concentration increased (up to 6-fold), with respect to raw cabbage. Copyright © 2015 Elsevier Ltd. All rights reserved.

Late Holocene ice wedges near Fairbanks, Alaska, USA: Environmental setting and history of growth

USGS Publications Warehouse

Hamilton, T.D.; Ager, T.A.; Robinson, S.W.

1983-01-01

Test trenches excavated into muskeg near Fairbanks in 1969 exposed a polygonal network of active ice wedges. The wedges occur in peat that has accumulated since about 3500 yr BP and have grown episodically as the permafrost table fluctuated in response to fires, other local site conditions and perhaps regional climatic changes. Radiocarbon dates suggest one or two episodes of ice-wedge growth between about 3500 and 2000 yr BP as woody peat accumulated at the site. Subsequent wedge truncation evidently followed a fire that charred the peat. Younger peat exhibits facies changes between sedge-rich components that filled troughs over the ice wedges and woody bryophytic deposits that formed beyond the troughs. A final episode of wedge development took place within the past few hundred years. Pollen data from the site indicate that boreal forest was present throughout the past 6000 yr, but that it underwent a gradual transition from a predominantly deciduous to a spruce-dominated assemblage. This change may reflect either local site conditions or a more general climatic shift to cooler, moister summers in late Holocene time. The history of ice-wedge growth shows that wedges can form and grow to more than 1 m apparent width under mean annual temperatures that probably are close to those of the Fairbanks area today (-3.5°C) and under vegetation cover similar to that of the interior Alaskan boreal forest. The commonly held belief that ice wedges develop only below mean annual air temperatures of -6 to -8°C in the zone of continuous permafrost is invalid.

Influence of organic matter, nutrients, and cyclodextrin on microbial and chemical herbicide and degradate dissipation in subsurface sediment slurries.

PubMed

Kerminen, Kaisa; Le Moël, Romain; Harju, Vilhelmiina; Kontro, Merja H

2018-03-15

Pesticides leaching from soil to surface and groundwater are a global threat for drinking water safety, as no cleaning methods occur for groundwater environment. We examined whether peat, compost-peat-sand (CPS) mixture, NH 4 NO 3 , NH 4 NO 3 with sodium citrate (Na-citrate), and the surfactant methyl-β-cyclodextrin additions enhance atrazine, simazine, hexazinone, dichlobenil, and the degradate 2,6-dichlorobenzamide (BAM) dissipations in sediment slurries under aerobic and anaerobic conditions, with sterilized controls. The vadose zone sediment cores were drilled from a depth of 11.3-14.6m in an herbicide-contaminated groundwater area. The peat and CPS enhanced chemical atrazine and simazine dissipation, and the peat enhanced chemical hexazinone dissipation, all oxygen-independently. Dichlobenil dissipated under all conditions, while BAM dissipation was fairly slow and half-lives could not be calculated. The chemical dissipation rates could be associated with the chemical structures and properties of the herbicides, and additive compositions, not with pH. Microbial atrazine degradation was only observed in the Pseudomonas sp. ADP amended slurries, although the sediment slurries were known to contain atrazine-degrading microorganisms. The bioavailability of atrazine in the water phase seemed to be limited, which could be due to complex formation with organic and inorganic colloids. Atrazine degradation by indigenous microbes could not be stimulated by the surfactant methyl-β-cyclodextrin, or by the additives NH 4 NO 3 and NH 4 NO 3 with Na-citrate, although the nitrogen additives increased microbial growth. Copyright © 2017 Elsevier B.V. All rights reserved.

Decoding the Secrets of Carbon Preservation and GHG Flux in Lower-Latitude Peatlands

NASA Astrophysics Data System (ADS)

Richardson, C. J.; Flanagan, N. E.; Wang, H.; Ho, M.; Hodgkins, S. B.; Cooper, W. T.; Chanton, J.; Winton, S.

2017-12-01

The mechanisms regulating peat decomposition and C carbon storage in peatlands are poorly understood, particularly with regard to the importance of the biochemical compounds produced by different plant species and in turn peat quality controls on C storage and GHG flux. To examine the role of carbon quality in C accretion in northern compared to tropical peatlands we completed field and lab studies on bog peats collected in Minnesota, North Carolina, Florida and Peru to answer three fundamental questions; 1) is tropical peat more recalcitrant than northern peat 2) does the addition of aromatic and phenolic C compounds increase towards the tropics 3) do differences in the chemical structure of organic matter explain variances in carbon storage and GHG flux in tropical versus northern peatlands? Our main hypothesize is that high concentrations of phenolics and aromatic C compounds produced in shrub and tree plant communities in peatlands coupled with the fire production of biochar aromatics in peatlands may provide a dual biogeochemical latch mechanism controlling microbial decomposition of peat even under higher temperatures and seasonal drought. By comparing the peat bog soil cores collected from the MN peat bogs, NC Pocosins, FL Everglades and Peru palm swamps we find that the soils in the shrub-dominant Pocosin contain the highest phenolics, which microbial studies indicate have the strongest resistance to microbial decomposition. A chemical comparison of plant driven peat carbon quality along a north to south latitudinal gradient indicates that tropical peatlands have higher aromatic compounds, and enhanced phenolics, especially after light fires, which enhances C storage and affect GHG flux across the latitudinal gradient.

Insights and issues with estimating Holocene peatland carbon stocks: a synthesis and review

NASA Astrophysics Data System (ADS)

Loisel, Julie; Yu, Zicheng

2014-05-01

Of all terrestrial ecosystems, peatlands are arguably the most efficient at sequestering carbon (C) over long time scales. However, ongoing and projected climate change could shift the balance between peat production and organic matter decomposition, potentially impacting the peat C sink capacity and modifying peat C fluxes to the atmosphere. Yet, the sign and magnitude of the peatland - C - climate feedback remain uncertain and difficult to assess because of large uncertainties in regional peat C stocks and limited understanding of peatland responses to climate change. Here we present results from the most comprehensive compilation of Holocene peat soil properties with associated carbon (C) and nitrogen (N) accumulation rates for northern peatlands. Our database consists of 268 peat cores from 215 sites located north of 45N. It encompasses regions within which peat C data have only recently become available, such as the West Siberia Lowlands, the Hudson Bay Lowlands, Kamchatka in Far East Russia, and the Tibetan Plateau. The database is publicly available at https://peatlands.lehigh.edu. Several scaling-up methods for estimating present-day peatland C stocks are presented, and uncertainties associated with each one of them are addressed. Likewise, the assumptions for calculating peat C volumes are discussed in light of conceptual models of spatial heterogeneity in peatland structure and function. We also examine the theoretical basis and underlying assumptions for the models of peatland lateral expansion and peat vertical growth used in estimating paleo peatland C stocks. Finally, we explore the importance of the fen-to-bog transition and of permafrost aggradation on C sequestration.

Dissolved organic carbon in soil solution of peat-moorsh soils on Kuwasy Mire

NASA Astrophysics Data System (ADS)

Jaszczyński, J.; Sapek, A.

2009-04-01

Key words: peat-moorsh soils, soil solution, dissolved organic carbon (DOC), temperature of soil, redox potential. The objective this study was the dissolved organic carbon concentration (DOC) in soil solution on the background of soil temperature, moisture and redox potential. The investigations were localized on the area of drained and agricultural used Kuwasy Mire, which are situated in the middle basin of Biebrza River, in North-East Poland. Research point was placed on a low peat soil of 110 cm depth managed as extensive grassland. The soil was recognized as peat-moorsh with the second degree of the moorshing process (with 20 cm of moorsh layer). The ceramic suction cups were installed in three replications at 30 cm depth of soil profile. The soil solution was continuously sampled by pomp of the automatic field station. The successive samples comprised of solution collected at the intervals of 21 days. Simultaneously, at the 20, 30 and 40 cm soil depths the measurements of temperature and determination of soil moisture and redox potential were made automatically. The mean twenty-four hours data were collected. The concentrations of DOC were determined by means of the flow colorimeter using the Skalar standard methods. Presented observations were made in 2001-2006. Mean DOC concentration in soil solution was 66 mg.dm-3 within all research period. A significant positive correlation between studied compound concentration and temperature of soil at 30 cm depth was observed; (correlation coefficient - r=0.55, number of samples - n=87). The highest DOC concentrations were observed during the season from July to October, when also a lower ground water level occurred. The DOC concentration in soil solution showed as well a significant correlation with the soil redox potential at 20 cm level. On this depth of describing soil profile a frontier layer between moorshing layer and peat has been existed. This layer is the potentially most active in the respect to biochemical transformation. On the other hand it wasn't possible to shown dependences on the DOC concentration from soil moisture. That probably results from a huge water-holding capacity of these type of peat soils, which are keeping a high moisture content even at a long time after decreasing of the groundwater table.

The Paradox of Excess Nitrogen in Boreal Peatlands: Biogeochemical Gaps in Nitrogen Cycling Revealed

NASA Astrophysics Data System (ADS)

Vile, M. A.; Prsa, T.; Wieder, R.; Lamers, L. P.

2011-12-01

Globally, peatlands cover 3-4 % of the Earth's land surface (over 4 million km 2, yet they store 25-30 % of the world's soil carbon (C) and 9-16% of the world's soil nitrogen (N, 8-15 Pg) in peat. As in other terrestrial ecosystems, the cycling of C and N is closely linked, especially for ombrotrophic bogs. Bogs receive nutrient and water exclusively from the atmosphere, which ensures an N-limited, nutrient-poor habitat. In Alberta, NW Canada, peatlands have received exceptionally low atmospheric inputs of N (< 1 7 kg/ha/yr) from their first introduction on the landscape ~ 7000 yrs bp, up to the present time. Paradoxically, despite these low inputs of atmospheric N deposition, bases on 210-fixation Pb dating of peat cores, we have shown that over the past 50 years these bogs have accumulated approximately 11-21 times more N in peat than can be explained by inputs of atmospheric N. A likely missing input is N2-fixation from cyanobacteria associated with Sphagnum mosses, however this process has been largely overlooked in boreal peatlands. Here we demonstrate the importance of N2-fixation in explaining the high accumulation rates of N found in unpolluted, boreal bogs of western Canada. Calibrated (using theoretical ratio of 1.5-3:1) rates of N2-fixation for 4 bogs in northern Alberta ranged from 1.6 to 8.0 ± 0.7 kg/ha/yr, indicating that 42-58 % of the N accumulated over in peat, can be attributed to biological N2-fixation. Although most of northern Alberta's peatlands continue to receive exceptionally low atmospheric N deposition rates, over the last 3 decades, rapid development and industrial expansion of Alberta's Oil Sands Mining (OSM) potentially threaten the pristine nature of peatlands through regionally elevated deposition of N-compounds (NOx). Prior to OSM, N inputs to bogs were limited exclusively to (1) biological N fixation, and (2) bulk background deposition. We examined the response of peatlands located in the OSM area to enhanced N deposition. Despite the large accumulation rates of N in peat, mean N:P ratios in Sphagnum moss capitula (11.0 ± 3.4; mean ± stdev) suggest that peat of boreal western Canada is still severely N limited and not limited by phosphorus. Collectively, these data underscore the severity of N-limitation in pristine bogs and their potential sensitivity to increased N inputs from oils sands mining. Additionally, because the majority of the data generated for N stress in peatlands is from eastern Canada and western Europe, we stress the need to encompass the response of bogs to N deposition within the bounds of the low N deposition gradient. We postulate the loss of symbiosis between Sphagnum and N-fixing microorganisms (cyanobacteria, bacteria) in nitrogen-polluted areas, and indicate its consequences at the species level (trade-off) and ecosystem level (including C sequestration).

Controls on Methanogenesis in Organic-Rich Anaerobic Environments

NASA Astrophysics Data System (ADS)

Wilson, R.; Tfaily, M.; Chanton, J.; Rich, V. I.; Saleska, S. R.; Holmes, B.; Langford, L.; Hanson, P. J.; Bridgham, S. D.; Hopple, A.; Keller, J.; Cory, A.; Kostka, J. E.

2017-12-01

Peatlands contain an amount of C equal to half the CO2 in the atmosphere. That C is stored as organic C (OC) in peat deposits which form when plant productivity exceeds heterotrophic respiration. This balance has been attributed to cold, anaerobic, low pH conditions which slow microbial respiration rates, high aromatic content which may inhibit microbial decomposition, and recalcitrance of OC under terminal electron-acceptor (TEA) depleted conditions. Peat has been described as a potential C bomb which could release Gt of C into the atmosphere if rising global temperatures shifted this balance in favor of increased microbial respiration. At the Spruce and Peatlands Responses Under Changing Environments (SPRUCE) experimental site in Minnesota, U.S.A., peat up to 2 m deep was heated (+2.25°C to +9°C above ambient) both in situ and in laboratory incubations to test the response of microbial respiration to increasing temperatures. Our results demonstrated (1) that temperature did not influence CO2 or CH4 production rates in deep anaerobic peat, (2) that microbial decomposition was dominated by dissolved OC rather than the solid phase peat, and (3) that microbial decomposition in surface peat may become more methanogenic with warming. This shift towards higher CH4 production relative to CO2 has significant climate change implications since CH4 is a much stronger greenhouse gas than CO2. Under TEA-poor, anaerobic conditions, such as peat deposits, thermodynamic principles dictate that cellulose, the dominant OC form in Sphagnum peat, should be mineralized into equimolar CO2 and CH­4. However, deviations from this predicted ratio abound. The literature of rumen, a system similar to peat in many ways, revealed a potential mechanism for sustaining elevated CO2 production without accumulating inhibitory H2. Using FTICRMS, we found ubiquitous hydrogenation of unsaturated OC which could be acting as TEAs in peat deposits. This mechanism has the further advantages of alleviating the toxicity of aromatic compounds and potentially making otherwise recalcitrant aromatic molecules susceptible to anaerobic decomposition thereby providing a critical step in the diagenesis of peat. Incubation experiments adding H2 support these findings and incubations of irradiated peat suggest an abiotic contribution to CO2 production.

Streambed peat lenses as redox-reactivity hotspots in lowland river hyporheic zones

NASA Astrophysics Data System (ADS)

Naden, Emma; Krause, Stefan; Cassidy, Nigel

2010-05-01

Hyporheic zones, as the direct interfaces between aquifers and rivers, are often characterised by increased redox reactivity and chemical transformation capacity. Depending on redox conditions and reaction types, hyporheic mixing of groundwater and surface water can lead to either attenuation or enrichment of pollutants or nutrients with diametrical implications for in-stream and aquifer hydro-ecological status. This study combines geophysical methods with distributed temperature sensor networks and nested multi-level sampling and analysis of hyporheic redox conditions and nutrient concentrations to investigate the reactive transport of nitrate at the aquifer-river interface of a UK lowland river. In stream Electric Resistivity Tomography and Ground Penetrating Radar (including core based ground truthing) have been applied to map the complex spatial patterns of highly conductive sandy and gravely sediments in contrast to semi-confining, low conductivity peat lenses which have been found to be characteristic for most lowland rivers. Reach scale (1km) spatial patterns and temporal dynamics of aquifer-river exchange have been identified by heat tracer experiments based on fibre-optical Distributed Temperature Sensing techniques combined with vertical thermocouple-arrays for tracing hyporheic flow paths. Spatial patterns of hyporheic redox conditions, dissolved oxygen (DO) and organic carbon (DOC) content as well as concentrations of major anions have been monitored in 48 nested multi-level mini-piezometers. Our investigations indicate that streambed temperature patterns were dominantly controlled by groundwater up-welling, causing cold spots in sandy and gravely sediments with high up-welling rates and low hyporheic residence times and warmer areas at the streambed surface where groundwater - surface water exchange was inhibited by streambed peat lenses. The flow-inhibiting peat structures have been found to cause semi-confined conditions in the up-welling groundwater, resulting in long residence times and increased redox-reactivity. Anoxic conditions and high DOC contents combined with long residence times underneath peat layers cause highly efficient denitrification rates, reducing nitrate concentrations from > 50mg/l to below the level of detection. In contrast, sandy and gravely areas of fast groundwater up-welling where characterized by only marginal changes in nitrate concentrations. The investigations lead to the development of a conceptual model of aquifer - river exchange and hyporheic reactivity in lowland rivers including temperature traceable hyporheic reactivity hotspots with high denitrification potential. The results for this exemplary field site highlight the substantial nutrient attenuation capacity of hyporheic zones at lowland rivers and emphasize the great importance of their consideration for river restoration programs and the assessment of water quality and ecological status.

Impact of Water Level on Carbon Sequestration at a Sub-tropical Peat Marsh

NASA Astrophysics Data System (ADS)

Sumner, D.; Hinkle, C.; Li, J.

2012-12-01

The impact of water level on sub-tropical peat marsh atmospheric/landscape carbon exchange was explored through eddy-covariance measurement of carbon dioxide and methane fluxes over a site at Blue Cypress Conservation Area in Florida. This site is vegetated with tall, dense sawgrass (Cladium jamaicense) and a thick accumulation of peat (over 3 m) suggesting a historically high primary productivity and carbon sequestration. Water managers are particularly interested in understanding how water-level controls can be directed to maintain topography through avoidance of excessive drought-induced oxidative losses of peat soil, as well as to minimize releases of greenhouse gases to the atmosphere. Comparison of net ecosystem productivity (NEP) during a wet year of continuous inundation and a drier year with a 9-month hydroperiod (NEP of 710 and 180 g C/m2/yr, respectively) suggests the positive impact of inundation on sequestration of carbon dioxide. These results are counter to previous research in short stature (1 m or less) sawgrass marshes in the Florida Everglades which indicate suppression of productivity during inundation. This seeming contradiction is probably best explained by the tall stature (over 2 m) of sawgrass at the study site in which inundation still does not cover a substantial fraction of the green leaves and the lower canopy is largely composed of brown and decaying leaves. Gross ecosystem productivity (GEP) was suppressed during the dry year (GEP = 1380 and 1030 g C/m2/yr for wet and dry years, respectively), probably as a consequence of canopy moisture stress. Respiration (R) was enhanced the year when water levels were farthest below land surface (R = 670 and 850 g C/m2/yr for wet and dry years, respectively) as a result of soil oxidation. GEP remained suppressed during the dry year even after re-flooding, probably because of relatively low photosynthetic leaf area that was the legacy of reduced canopy growth rates during the drought. Over a seven-month measurement period spanning a dry-to-inundated transition in the marsh, methane flux was negligible during non-inundated periods, but was substantial (averaging 80 g C/m2/yr) during wet periods. The results of this study suggest that water level is a critical control on atmospheric carbon exchanges at this peat marsh with implications for water management and strategic planning under potentially drier conditions that might occur in response to climate change.

Impact of Water Level on Carbon Sequestration at a Sub-tropical Peat Marsh

NASA Astrophysics Data System (ADS)

Sumner, D.; Hinkle, C.; Graham, S.; Li, J.

2013-12-01

The impact of water level on sub-tropical peat marsh atmospheric/landscape carbon exchange was explored through eddy-covariance measurement of carbon dioxide and methane fluxes over a site at Blue Cypress Conservation Area in Florida. This site is vegetated with tall, dense sawgrass (Cladium jamaicense) and a thick accumulation of peat (over 3 m) suggesting a historically high primary productivity and carbon sequestration. Water managers are particularly interested in understanding how water-level controls can be directed to maintain topography through avoidance of excessive drought-induced oxidative losses of peat soil, as well as to minimize releases of greenhouse gases to the atmosphere. Comparison of net ecosystem productivity (NEP) during a wet year of continuous inundation and a drier year with a 9-month hydroperiod (NEP of 710 and 180 g C/m2/yr, respectively) suggests the positive impact of inundation on sequestration of carbon dioxide. These results are counter to previous research in short stature (1 m or less) sawgrass marshes in the Florida Everglades which indicate suppression of productivity during inundation. This seeming contradiction is probably best explained by the tall stature (over 2 m) of sawgrass at the study site in which inundation still does not cover a substantial fraction of the green leaves and the lower canopy is largely composed of brown and decaying leaves. Gross ecosystem productivity (GEP) was suppressed during the dry year (GEP = 1380 and 1030 g C/m2/yr for wet and dry years, respectively), probably as a consequence of canopy moisture stress. Respiration (R) was enhanced the year when water levels were farthest below land surface (R = 670 and 850 g C/m2/yr for wet and dry years, respectively) as a result of soil oxidation. GEP remained suppressed during the dry year even after re-flooding, probably because of relatively low photosynthetic leaf area that was the legacy of reduced canopy growth rates during the drought. Over a seven-month measurement period spanning a dry-to-inundated transition in the marsh, methane flux was negligible during non-inundated periods, but was substantial (averaging 80 g C/m2/yr) during wet periods. The results of this study suggest that water level is a critical control on atmospheric carbon exchanges at this peat marsh with implications for water management and strategic planning under potentially drier conditions that might occur in response to climate change.

Characterization and source apportionment of particulate matter < or = 2.5 micrometer in Sumatra, Indonesia, during a recent peat fire episode.

PubMed

See, Siao Wei; Balasubramanian, Rajasekhar; Rianawati, Elisabeth; Karthikeyan, Sathrugnan; Streets, David G

2007-05-15

An intensive field study was conducted in Sumatra, Indonesia, during a peat fire episode to investigate the physical and chemical characteristics of particulate emissions in peat smoke and to provide necessary data for source-receptor analyses. Ambient air sampling was carried out at three different sites located at varying distances from the peatfires to determine changes in mass and number concentrations of PM2.5 and its chemical composition (carbonaceous and nitrogenous materials, polycyclic aromatic hydrocarbons, water-soluble inorganic and organic ions, and total and water-soluble metals). The three sites represent a rural site directly affected by the local peat combustion, a semirural site, and an urban site situated downwind of the peat fires. The mass concentration of PM2.5 and the number concentration of airborne particles were as high as 1600 microg/m3 and 1.7 x 10(5) cm(-3), respectively, in the vicinity of peat fires. The major components of PM2.5 in peat smoke haze were carbonaceous particles, particularly organic carbon, NO3-, and SO4(2-), while the less abundant constituents included ions such as NH4+, NO2-, Na+, K+, organic acids, and metals such as Al, Fe, and Ti. Source apportionment by chemical mass balance receptor modeling indicates that peat smoke can travel long distances and significantly affect the air quality at locations downwind.

Measuring Outcomes for Dysphagia: Validity and Reliability of the European Portuguese Eating Assessment Tool (P-EAT-10).

PubMed

Nogueira, Dália Santos; Ferreira, Pedro Lopes; Reis, Elizabeth Azevedo; Lopes, Inês Sousa

2015-10-01

The purpose of this study was to evaluate the validity and the reliability of the European Portuguese version of the EAT-10 (P-EAT-10). This research was conducted in three phases: (i) cultural and linguistic adaptation; (ii) feasibility and reliability test; and (iii) validity tests. The final sample was formed by a cohort of 520 subjects. The P-EAT-10 index was compared for socio-demographic and clinic variables. It was also compared for both dysphagic and non-dysphagic groups as well as for the results of the 3Oz wst. Lastly, the P-EAT-10 scores were correlated with the EuroQol Group Portuguese EQ-5D index. The Cronbach's α obtained for the P-EAT-10 scale was 0.952 and it remained excellent even if any item was deleted. The item-total and the intraclass correlation coefficients were very good. The P-EAT-10 mean of the non-dysphagic cohort was 0.56 and that of the dysphagic cohort was 14.26, the mean comparison between the 3Oz wst groups and the P-EAT-10 scores were significant. A significant higher perception of QoL was also found among the non-dysphagic subjects. P-EAT-10 is a valid and reliable measure that may be used to document dysphagia which makes it useful both for screening in clinical practice and in research.

Thermomagnetic properties of peat-soil layers from Sag pond near Lembang Fault, West Java, Indonesia

NASA Astrophysics Data System (ADS)

Iryanti, Mimin; Wibowo, Dimas Maulana; Bijaksana, Satria

2015-09-01

Sag pond is a body of water near fault system as water flows blocked by the fault. Sag pond is a special type of environment for peat formation as peat layers in were deposited as the fault moves in episodic fashion. Depending on the history of the fault, peat layers are often interrupted by soil layers. In this study, core of peat-soil layers from a Sag pond in Karyawangi Village near Lembang Fault was obtained and analyzed for its magnetic properties. The 5 m core was obtained using a hand auger. Individual samples were obtained every cm and measured for their magnetic susceptibility. In general, there are three distinct magnetic susceptibility layers that were associated with peat and soil layers. The upper first 1 m is unconsolidated mud layer with its relatively high magnetic susceptibility. Between 1-2.81 m, there is consolidated mud layer and the lowest part (2.82-5) m is basically peat layer. Six samples were then measured for their thermomagnetic properties by measuring their susceptibility during heating and cooling from room temperature to 700°C. The thermomagnetic profiles provide Curie temperatures for various magnetic minerals in the cores. It was found that the upper part (unconsolidated mud) contains predominantly iron-oxides, such as magnetite while the lowest part (peat layer) contains significant amount of iron-sulphides, presumably greigite.

Agricultural management impact on physical and chemical functions of European peat soils.

NASA Astrophysics Data System (ADS)

Piayda, Arndt; Tiemeyer, Bärbel; Dettmann, Ullrich; Bechtold, Michel; Buschmann, Christoph

2017-04-01

Peat soils offer numerous functions from the global to the local scale: they constitute the biggest terrestrial carbon storage on the globe, form important nutrient filters for catchments and provide hydrological buffer capacities for local ecosystems. Peat soils represent a large share of soils suitable for agriculture in temperate and boreal Europe, pressurized by increasing demands for production. Cultivated peat soils, however, show extreme mineralization rates of the organic substance and turn into hotspots for green house gas emissions, are highly vulnerable to land surface subsidence, soil and water quality deterioration and thus crop failure. The aim of this study is to analyse the impact of past agricultural management on soil physical and chemical functions of peat soils in six European countries. We conducted standardized soil mapping, soil physical/chemical analysis, ground water table monitoring and farm business surveys across 7 to 10 sites in Germany, The Netherlands, Denmark, Estonia, Finland and Sweden. The results show a strong impact of past agricultural management on peat soil functions across Europe. Peat soil under intensive arable land use consistently offer lowest bearing capacities in the upper 10 cm compared to extensive and intensive grassland use, which is a major limiting factor for successful agricultural practice on peat soils. The difference can be explained by root mat stabilization solely, since soil compaction in the upper 25cm is highest under arable land use. A strong decrease of available water capacity and saturated hydraulic conductivity is consequently observed under arable land use, further intensifying hydrological problems like ponding, drought stress and reductions of hydrological buffer capacities frequently present on cultivated peat soils. Soil carbon stocks clearly decrease with increasing land use intensity, showing highest carbon stocks on extensive grassland. This is supported by the degree of decomposition, which is lowest for extensive grass land. Both findings indicate a strong impact of land use intensity and management on soil carbon losses and peat conservation on the European scale. This study provides evidence how functions of peat soils, valuable for successful agricultural production and relevant for climate change mitigation, are impacted by agricultural management.

Experimental warming differentially affects microbial structure and activity in two contrasted moisture sites in a Sphagnum-dominated peatland.

PubMed

Delarue, Frédéric; Buttler, Alexandre; Bragazza, Luca; Grasset, Laurent; Jassey, Vincent E J; Gogo, Sébastien; Laggoun-Défarge, Fatima

2015-04-01

Several studies on the impact of climate warming have indicated that peat decomposition/mineralization will be enhanced. Most of these studies deal with the impact of experimental warming during summer when prevalent abiotic conditions are favorable to decomposition. Here, we investigated the effect of experimental air warming by open-top chambers (OTCs) on water-extractable organic matter (WEOM), microbial biomasses and enzymatic activities in two contrasted moisture sites named Bog and Fen sites, the latter considered as the wetter ones. While no or few changes in peat temperature and water content appeared under the overall effect of OTCs, we observed that air warming smoothed water content differences and led to a decrease in mean peat temperature at the warmed Bog sites. This thermal discrepancy between the two sites led to contrasting changes in microbial structure and activities: a rise in hydrolytic activity at the warmed Bog sites and a relative enhancement of bacterial biomass at the warmed Fen sites. These features were not associated with any change in WEOM properties namely carbon and sugar contents and aromaticity, suggesting that air warming did not trigger any shift in OM decomposition. Using various tools, we show that the use of single indicators of OM decomposition can lead to fallacious conclusions. Lastly, these patterns may change seasonally as a consequence of complex interactions between groundwater level and air warming, suggesting the need to improve our knowledge using a high time-resolution approach. Copyright © 2015 Elsevier B.V. All rights reserved.

Seven centuries of atmospheric Pb deposition recorded in a floating mire from Central Italy

NASA Astrophysics Data System (ADS)

Zaccone, Claudio; Lobianco, Daniela; D'Orazio, Valeria; Miano, Teodoro M.; Shotyk, William

2016-04-01

Floating mires generally consist of emergent vegetation rooted in highly organic buoyant mats that rise and fall with changes in water level. Generally speaking, the entire floating mass (mat) is divided into a mat root zone and an underlying mat peat zone. Floating mires are distributed world-wide; large areas of floating marsh occur along rivers and lakes in Africa, the Danube Delta in Romania, the Amazon River in South America, and in the Mississippi River delta in USA, whereas smaller areas occur also in The Netherlands, Australia and Canada. While peat cores from ombrotrophic bogs have been often (and successfully) used to reconstruct changes in the atmospheric deposition of several metals (including Pb), no studies are present in literature about the possibility to use peat profiles from floating mires. To test the hypothesis that peat-forming floating mires could provide an exceptional tool for environmental studies, a complete, 4-m deep peat profile was collected in July 2012 from the floating island of Posta Fibreno, a relic mire in the Central Italy. This floating island has a diameter of ca. 30 m, a submerged thickness of about 3 m, and the vegetation is organized in concentric belts, from the Carex paniculata palisade to the Sphagnum palustre centre. The whole core was frozen cut each 1-to-2 cm (n =231), and Pb determined by quadrupole ICP-MS (at the ultraclean SWAMP lab, University of Alberta, Canada) in each sample throughout the first 100 cm, and in each odd-numbered slice for the remaining 300 cm. The 14C age dating of organic sediments (silty peat) isolated from the sample at 385 cm of depth revealed that the island probably formed ca. 700 yrs ago. Lead concentration trend shows at least two main zones of interest, i.e., a clear peak (ranging from 200 to 1600 ppm) between 110-115 cm of depth, probably corresponding to early 1960's - late 1970's, and a broad band (80-160 ppm) between 295-320 cm of depth, corresponding to approximately AD 1480-1650. Lead concentrations were normalized to those of Th, a conservative, lithophile element often used as an indicator of the abundance of mineral particles. Crustal enrichment factor values, calculated by normalizing the Pb/Th ratio in peat samples to the corresponding ratio for the Upper Continental Crust, clearly show that almost all the Pb reaching this floating isle in the last seven centuries is of anthropogenic origin. In particular, while the big peak around 100-115 cm of depth is associated with that of Sb, the band around 300 cm characterized also the trend of several other major and trace elements (i.e., Ag, Al, Ba, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sr, Th, Tl, U, V, Y, Zn) with the exception of Sb. Although γ-spectrometry measurement (210Pb, 137Cs and 241Am) for the first 100 cm of this core is still on-going, at the best of our knowledge, this work may provide the first Pb chronology obtained from a (4 m) deep floating mire. Furthermore, it is to note that a) this floating mire could consist of the southernmost European population of Sphagnum, and b) this core shows a great potential to be used as archive of environmental changes, especially considering its high resolution (1 cm = 0.5 yr in the first 100 cm, and 2-2.5 yrs in the remaining 300 cm of depth). The Authors thank the Municipality of Posta Fibreno, Managing Authority of the Regional Natural Reserve of Lake Posta Fibreno, for allowing peat cores sampling.

Small spatial variability in methane emission measured from a wet patterned boreal bog

NASA Astrophysics Data System (ADS)

Korrensalo, Aino; Männistö, Elisa; Alekseychik, Pavel; Mammarella, Ivan; Rinne, Janne; Vesala, Timo; Tuittila, Eeva-Stiina

2018-03-01

We measured methane fluxes of a patterned bog situated in Siikaneva in southern Finland from six different plant community types in three growing seasons (2012-2014) using the static chamber method with chamber exposure of 35 min. A mixed-effects model was applied to quantify the effect of the controlling factors on the methane flux. The plant community types differed from each other in their water level, species composition, total leaf area (LAITOT) and leaf area of aerenchymatous plant species (LAIAER). Methane emissions ranged from -309 to 1254 mg m-2 d-1. Although methane fluxes increased with increasing peat temperature, LAITOT and LAIAER, they had no correlation with water table or with plant community type. The only exception was higher fluxes from hummocks and high lawns than from high hummocks and bare peat surfaces in 2013 and from bare peat surfaces than from high hummocks in 2014. Chamber fluxes upscaled to ecosystem level for the peak season were of the same magnitude as the fluxes measured with the eddy covariance (EC) technique. In 2012 and in August 2014 there was a good agreement between the two methods; in 2013 and in July 2014, the chamber fluxes were higher than the EC fluxes. Net fluxes to soil, indicating higher methane oxidation than production, were detected every year and in all community types. Our results underline the importance of both LAIAER and LAITOT in controlling methane fluxes and indicate the need for automatized chambers to reliably capture localized events to support the more robust EC method.

Re-establishment of hummock topography promotes tree regeneration on highly disturbed moderate-rich fens.

PubMed

Lieffers, Victor J; Caners, Richard T; Ge, Hangfei

2017-07-15

Winter exploration of oil sands deposits underlying wooded fens mostly eliminates the hummock-hollow topography on drilling pads and the ice roads leading to them, after their abandonment in spring. Recovery of black spruce (Picea mariana (P. Mill.) B.S.P.) and tamarack (Larix laricina (Du Roi) K. Koch) on these disturbed peatlands is thought to depend on the recovery of hummock topography. In late winter, numerous large blocks of frozen peat (1.5 × 1.5 m) were lifted out of the flattened drilling pads and positioned beside their excavated hollows; this was done on six temporary pads. Four years later, the condition of the mounds and the regeneration of conifers from natural seed dispersal were assessed on these elevated mounds compared to adjacent flattened areas of the pads. Then, conifer seedling density was more than five times higher on elevated spots than the mostly flat, flood-prone areas between them, and seedling density was positively related to mound height and strength of seed source. Higher mounds tended to have larger seedlings. Mounds on some of the pads were heavily eroded down; these pads had peat with higher humification, and operationally these pads were also treated in late winter when peat was thawing and fractured into pieces during mound construction. Developing a large volume of elevated substrate that persists until natural hummock-forming mosses can establish is thought necessary for tree recruitment and the recovery of the habitat for the threatened woodland caribou of this region. Copyright © 2017 Elsevier Ltd. All rights reserved.

Methane and CO2 fluxes from peat soil, palm stems and field drains in two oil palm plantations in Sarawak, Borneo, on different tropical peat soil types.

NASA Astrophysics Data System (ADS)

Manning, Frances; Lip Khoon, Kho; Hill, Tim; Arn Teh, Yit

2017-04-01

Oil palm plantations have been expanding rapidly on tropical peat soils in the last 20 years, with 50 % of SE Asian peatlands now managed as industrial or small-holder plantations, up from 11% in 1990. Tropical peat soils are an important carbon (C) store, containing an estimated 17 % of total peatland C. There are large uncertainties as to the soil C dynamics in oil palm plantations on peat due to a shortage of available data. It is therefore essential to understand the soil C cycle in order to promote effective management strategies that optimise yields, whilst maintaining the high C storage capacity of the soil. Here we present CO2 and CH4 fluxes from two oil palm plantations in Sarawak, Malaysia on peat soils. Data were collected from different surface microforms within each plantation that experienced different surface management practices. These included the area next to the palm, in bare soil harvest paths, beneath frond piles, underneath cover crops, from the surface of drains, and from palm stems. Data were collected continuously over one year and analysed with different environmental variables, including soil temperature, WTD, O2, soil moisture and weather data in order to best determine the constraints on the dataset. Total soil respiration (Rtot) varied between 0.09 and 1.59 g C m-2 hr-1. The largest fluxes (0.59 - 1.59 g C m-2 hr-1) were measured next to the palms. Larger CO2 fluxes were observed beneath the cover crops than in the bare soil. This trend was attributed to priming effects from the input of fresh plant litter and exudates. Peat soil type was shown to have significantly different fluxes. The different plantations also had different environmental drivers best explaining the variation in Rtot - with soil moisture being the most significant variable on Sabaju series soil and soil temperature being the most significant environmental variable in the plantation with the Teraja series soil. Rtot was shown to reduce significantly with increasing distance from the palm. The relationship between Rtot and root biomass, which also decreased significantly with increasing distance from the palm, allowed for the partitioning of Rtot into peat oxidation and Ra. Here rates of peat oxidation were estimated to be 0.11 g C m-2 hr-1 following partitioning, and 0.16 g C m-2 hr-1 without partitioning. Methane fluxes varied between 0 and 1.95 g C m-2 hr-1. The largest methane fluxes were emitted from collection drains. Methane oxidation was occasionally observed in field drains, when the water table dropped below the depth of the drain. Soil methane fluxes were lower than those from collection drains. The highest methane fluxes were observed next to palms (0.02 mg C m-2 hr-1) and the lowest under frond piles (0.08 mg C m-2 hr-1). Methane emissions were measured from the palm stems. Preliminary data gives a range between 0.005 and 0.27 µg C m-2 hr-1. These results show wide ranges in both CO2 and CH4 emissions from different sources within the plantations, with the collection drains being the largest source of C fluxes.

Mycobacterium avium subsp. hominissuis infection in swine associated with peat used for bedding.

PubMed

Johansen, Tone Bjordal; Agdestein, Angelika; Lium, Bjørn; Jørgensen, Anne; Djønne, Berit

2014-01-01

Mycobacterium avium subsp. hominissuis is an environmental bacterium causing opportunistic infections in swine, resulting in economic losses. Additionally, the zoonotic aspect of such infections is of concern. In the southeastern region of Norway in 2009 and 2010, an increase in condemnation of pig carcasses with tuberculous lesions was seen at the meat inspection. The use of peat as bedding in the herds was suspected to be a common factor, and a project examining pigs and environmental samples from the herds was initiated. Lesions detected at meat inspection in pigs originating from 15 herds were sampled. Environmental samples including peat from six of the herds and from three peat production facilities were additionally collected. Samples were analysed by culture and isolates genotyped by MLVA analysis. Mycobacterium avium subsp. hominissuis was detected in 35 out of 46 pigs, in 16 out of 20 samples of peat, and in one sample of sawdust. MLVA analysis demonstrated identical isolates from peat and pigs within the same farms. Polyclonal infection was demonstrated by analysis of multiple isolates from the same pig. To conclude, the increase in condemnation of porcine carcasses at slaughter due to mycobacteriosis seemed to be related to untreated peat used as bedding.

Mycobacterium avium subsp. hominissuis Infection in Swine Associated with Peat Used for Bedding

PubMed Central

Johansen, Tone Bjordal; Lium, Bjørn; Jørgensen, Anne; Djønne, Berit

2014-01-01

Mycobacterium avium subsp. hominissuis is an environmental bacterium causing opportunistic infections in swine, resulting in economic losses. Additionally, the zoonotic aspect of such infections is of concern. In the southeastern region of Norway in 2009 and 2010, an increase in condemnation of pig carcasses with tuberculous lesions was seen at the meat inspection. The use of peat as bedding in the herds was suspected to be a common factor, and a project examining pigs and environmental samples from the herds was initiated. Lesions detected at meat inspection in pigs originating from 15 herds were sampled. Environmental samples including peat from six of the herds and from three peat production facilities were additionally collected. Samples were analysed by culture and isolates genotyped by MLVA analysis. Mycobacterium avium subsp. hominissuis was detected in 35 out of 46 pigs, in 16 out of 20 samples of peat, and in one sample of sawdust. MLVA analysis demonstrated identical isolates from peat and pigs within the same farms. Polyclonal infection was demonstrated by analysis of multiple isolates from the same pig. To conclude, the increase in condemnation of porcine carcasses at slaughter due to mycobacteriosis seemed to be related to untreated peat used as bedding. PMID:25431762

Distributions of Heavy Metals and Benzo[ a]pyrene in Oligotrophic Peat Soils and Peat Gleyzems of Northeastern Sakhalin

NASA Astrophysics Data System (ADS)

Lipatov, D. N.; Shcheglov, A. I.; Manakhov, D. V.; Karpukhin, M. M.; Zavgorodnyaya, Yu. A.; Tsvetnova, O. B.

2018-05-01

The contents and profile distributions of Cr, Ni, Cu, Zn, Cd, Hg, Pb, and benzo[a]pyrene in oligotrophic peat soils, oligotrophic peat gley soils (Dystric Fibric Histosols), humus-impregnated peat gleyzems (Dystric Histic Gleysols), and mucky gleyzems (Dystric Gleysols) have been analyzed with consideration for their degree of oligotrophicity and anthropogenic loads. Horizons with the accumulation (O, Tpyr, TT) and removal (Ghi,e) of heavy metals have been revealed. The increase in the content of heavy metals and benzo[ a]pyrene in the upper layer of oligotrophic peat soils under technogenic fallouts in the impact zone of flare and motor transport has been considered. Statistical parameters of the spatial variation of parameters in organic and gley horizons have been calculated. The variation coefficients of pollutant elements (Pb and Zn) in the surface horizons of soils increase to 100-125%. Positive correlations revealed between the content of some heavy metals in litter indicate their bioaccumulation and possible joint input with aerotechnogenic fallouts. No correlations are found between the contents of benzo[ a]pyrene and heavy metals, but a reliable negative correlation with the ash content is noted in the peat horizon.

Rice husk ash (RHA) as a partial cement replacement in modifying peat soil properties

NASA Astrophysics Data System (ADS)

Daud, Nik Norsyahariati Nik; Daud, Mohd Nazrin Mohd; Muhammed, Abubakar Sadiq

2018-02-01

This paper describes the effect of rice husk ash (RHA) and ordinary Portland cement (OPC) as a potential binder for modifying the properties of peat soil. The amounts RHA and OPC added to the peat soil sample, as percentage of the dry soil mass were in the range of 10-15% and 15%, respectively. Observations were made for the changes in the properties of the soil such as maximum dry density (MDD), optimum moisture content (OMC) and shear strength. Scanning Electron Micrograph-Energy Dispersive X-Ray (SEM-EDX) test were also conducted to observe the microstructure of treated and untreated peat soil. The results show that the modified soil of MDD and OMC values are increased due to the increment amount of binder material. Shear strength values of modified peat showing a good result by assuming that it is relative to the formation of major reaction products such as calcium silicate hydrate (C-S-H). The presence of C-S-H formation is indicated by the results produced from microstructural analysis of peat before and after modification process. This depicts the potential usage of RHA as a partial cement replacement in peat soil which is also improving its engineering properties.

Effect of Peat on Physicomechanical Properties of Cemented Brick

PubMed Central

Hashim, Roslan; Kurnia, Ryan

2014-01-01

The popularity of low cost, lightweight, and environmentally affable masonry unit in building industry carries the need to investigate more flexible and adaptable brick component as well as to retain the requirements confirmed in building standards. In this study, potential use of local materials used as lightweight building materials in solving the economic problems of housing has been investigated. Experimental studies on peat added bricks have been carried out. It demonstrates the physicomechanical properties of bricks and investigates the influence of peat, sand, and cement solid bricks to the role of various types of constructional applications. The achieved compressive strength, spitting strength, flexural strength, unit weight, and ultrasonic pulse velocity are significantly reduced and the water absorption is increased with percentage wise replacement of peat as aggregate in the samples. The maximum 20% of (% mass) peat content meets the requirements of relevant well-known international standards. The experimental values illustrate that, the 44% volumetric replacement with peat did not exhibit any sudden brittle fracture even beyond the ultimate loads and a comparatively smooth surface is found. The application of peat as efficient brick substance shows a potential to be used for wall and a viable solution in the economic buildings design. PMID:24982941

The influence of aeration and temperature on the structure of bacterial complexes in high-moor peat soil

NASA Astrophysics Data System (ADS)

Kukharenko, O. S.; Pavlova, N. S.; Dobrovol'Skaya, T. G.; Golovchenko, A. V.; Pochatkova, T. N.; Zenova, G. M.; Zvyagintsev, D. G.

2010-05-01

The number and taxonomic structure of the heterotrophic block of aerobic and facultative anaerobic bacteria were studied in monoliths from a high-moor peat (stored at room temperature and in a refrigerator) and in the peat horizons mixed in laboratory vessels. The monitoring lasted for a year. In the T0 horizon, spirilla predominated at room and low temperatures; in the T1 and T2 horizons, bacilli were the dominants. The continuous mixing of the peat layers increased the oxygen concentration and the peat decomposition; hence, the shares of actinomycetes and bacilli (bacteria of the hydrolytic complex) increased. In the peat studied, the bacilli were in the active state; i.e., vegetative cells predominated, whose amount ranged from 65 to 90%. The representatives of the main species of bacilli (the facultative anaerobic forms prevailed) hydrolyzed starch, pectin, and carboxymethylcellulose. Thus, precisely sporiferous bacteria can actively participate in the decomposition of plant polysaccharides in high-moor peat soils that are characterized by low temperatures and an oxygen deficit. The development of actinomycetes is inhibited by low temperatures; they can develop only under elevated temperature and better aeration.

Testing the potential of bacterial branched tetraether membrane lipids as temperature proxy in peat and immature coal deposits

NASA Astrophysics Data System (ADS)

Weijers, J. W. H.; Steinmann, P.; Hopmans, E. C.; Basiliko, N.; Finkelstein, S. A.; Johnson, K. R.; Schouten, S.; Sinninghe Damsté, J. S.

2012-04-01

Branched glycerol dialkyl glycerol tetraether (brGDGT) membrane lipids occur ubiquitously in peat and soil. In soil, the degree of methylation and cyclisation of branched tetraethers (MBT index and CBT ratio, respectively) has shown to relate to both soil pH and annual mean air temperature (MAT). Using this relation, past annual MATs can be reconstructed by analysing brGDGTs in marine sediment records near large river outflows. More recently, the potential of this MBT/CBT proxy is also being explored in lakes. Despite being more abundant in peat than soils, however, the utility of the proxy has not yet been fully explored in peat records. Present day peat records generally extent back to the early Holocene, but if the MBT/CBT proxy were shown to be applicable in peat deposits, there is also potential to apply it to immature coal deposits like lignites, which could provide valuable snapshots of continental climate back to the early Cenozoic. Here results are presented of analyses of different peats in south eastern Canada, showing that the pH of peat along a nutrient gradient is rather well reflected by the CBT. Annual MAT reconstructions based on the MBT/CBT soil calibration, however, tend to overestimate measured MAT. This is also the case for peat analysed from the surface of Etang de la Gruère peat bog in the Swiss Jura Mountains. Along the 6m depth profile of this bog (~13ka), CBT-reconstructed pH is compared with in-situ measured pore water pH showing that the brGDGT composition does not reflect present-day in-situ conditions. Instead, it reflects a stratigraphic boundary between Carex and Sphagnum dominated peat at 4 m depth that is not present in the pore water profile, testifying to a 'fossil' nature of the brGDGTs down the peat bog. Analyses of three immature coals of the Argonne Premium Coal Series reveal that branched GDGTs are present in the most immature coal, the Beulah Zap lignite (Ro = 0.25%), and only just above detection limit in the Wyodak Anderson coal (Ro = 0.32%), both of about the same age (Late Palaeocene). In the more mature Illinois #6 coal (Ro = 0.46%), brGDGTs are completely absent. In the Denver Basin, a comparison is made between outcrop and drilled core samples of Palaeocene lignites. BrGDGTs are preserved in the core samples, although in low quantities compared to peat. Outcrop samples are clearly overprinted by modern soil derived brGDGTs, despite digging a meters deep trench, which shows the need to obtain fresh non-weathered samples by coring. Reconstructed annual MAT for both the Beulah Zap and the Denver Basin lignites are several degrees higher than estimates based on leaf margin and oxygen isotope analyses from the same sites. Both reconstructions do testify, nevertheless, to the warm continental conditions during the early Cenozoic of the central U.S.A.. Although further validation is required, potentially in the form of a specific peat calibration, these results do show potential for application of the MBT/CBT temperature proxy in peat and lignite deposits.

Production of fuel ethanol from cellulosic peat for future transportation systems.

DOT National Transportation Integrated Search

2007-12-01

The production of bioethanol from peat is proposed. A search of the available : literature yields no prior information on the use of peat as a carbon source for : bioethanol. This proposal addresses the production in the most cost-effective manner : ...

SPRUCE S1 Bog Vegetation Survey and Peat Depth Data: 2009

DOE Data Explorer

Hanson, P. J. [Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, U.S.A

2009-12-31

This data set reports the results of a field survey of the S1 Bog to characterize the vegetation and to determine peat depth. The survey was conducted on September 21 and 22, 2009. The initial survey of vegetation and peat depth characteristics of the target bog was conducted to evaluate the logical locations for installing replicated experimental blocks for SPRUCE. The goal was to identify multiple locations of uniform aboveground vegetation and belowground peat depth for positioning experimental units within the bog.

Benthic macroinvertebrates and the use of stable isotopes (δ13C and δ15N) in the impact assessment of peatland use on boreal stream ecosystems

NASA Astrophysics Data System (ADS)

Nieminen, Mika L.; Daza Secco, Emmanuela; Nykänen, Hannu; Meissner, Kristian

2013-04-01

Stable isotope analysis (SIA) can provide insights into carbon flow dynamics and trophic positions of consumers in food webs. SIA is used in this study, where we assess the possible changes in the basal resources of Finnish boreal stream ecosystems and differences in the impact of two forms of peatland use, forestry and peat mining. About 30% of the total land area of Finland is classified as peatland, of which about 55% has been drained for forestry and about 0.6% is in peat production. Unlike forestry, peat production is regionally less scattered and can thus have measurable local impacts although the total area of peat production is small. Three watersheds were used as study areas. Within each watershed, one stream drains a subcatchment affected only by peat mining, whereas the other stream flows through a subcatchment affected by forestry. The two subcatchment streams merge to form a single stream flowing into a lake. Studied watersheds were subject to no other forms of land use. In addition to the impacted sites, we used two pristine natural mire and two natural forest catchments as controls. We analysed the stable isotopes of carbon (δ13C) and nitrogen (δ15N) from benthic macroinvertebrates, stream bank soil, stream sediment, and dissolved organic carbon (DOC) in stream water. Samples for stable isotope analyses were collected in the summer of 2011 and samples for invertebrate community analyses in the autumn of 2011. Upon sampling we measured several physical parameters at each sampling site. In addition, stream water samples collected in summer and autumn 2012 were analysed for CH4 and CO2 gas concentrations and autumn gas samples also for their δ13C values. Our initial SIA results of invertebrates suggest some degree of discrimination between different sources of OM and possible effects on feeding habits, presumably due to the quality of the basal resources. We will explore this result further by examining not only taxonomical structure, but also the role that functional feeding groups may have on results. Initial results on invertebrate community structure in response to land use indicate the importance of geographical site location over land use effects. We suggest that SIA results should be interpreted together with benthic macroinvertebrate community analyses to get more insight into ecological impacts of different peatland uses with respect to changed food quality. Further, we will assess whether CH4 and CO2 could be used as an indicator of basal resource change. In future studies, we will address the role of the quality and quantity of the basal resources in more detail, which is likely to provide more insight into the effects of different forms of peatland use on aquatic ecosystems.

Altered peat hydrophysical properties following drainage and wildfire increases peatland vulnerability to ecosystem regime shift

NASA Astrophysics Data System (ADS)

Waddington, James; Kettridge, Nick; Sherwood, James; Granath, Gustaf

2015-04-01

Northern peatlands represent a globally significant carbon reservoir, composed largely of legacy carbon which is no longer part of the active carbon cycle. However, it is unclear whether this legacy carbon is vulnerable as a result of enhanced peat smouldering and combustion under the moderate drying conditions predicted for northern peatlands as a result of climate change and/or disturbance from forestry, mining, and associated transport development. A significant loss in legacy carbon as a result of wildfire has already been observed in smaller tropical peatlands where deep peat soils have been destabilized due to severe drainage and a shift in vegetation. Capitalizing on a unique long-term experiment, we quantify the post-wildfire recovery of a northern peatland several decades post drainage. We show that the moderate drop in water table position predicted for most northern regions triggers a shift in vegetation composition, previously observed within only severely disturbed tropical peatlands, when accompanied by wildfire. The combined impact of moderate drainage followed by wildfire resulted in a shift of the peat surface down the peat profile, exposing denser peat at the surface. In undisturbed northern peatlands where depth of burn is typically low, low-density near-surface peats help regulate water-table position and near-surface moisture availability post-fire, both of which are favourable to Sphagnum recolonization. As a result of drainage and fire at the study site, the self-regulating properties of the low-density Sphagnum surface were lost. We demonstrate that changes in peat hydrophysical properties increased hydrological limitations to Sphagnum recovery leading to the conversion to a non-carbon accumulating shrub-grass ecosystem. This new ecosystem is likely to experience a low intensity, high frequency wildfire regime, which will further deplete the legacy carbon stored in the peat.

Inorganic geochemistry of domed peat in Indonesia and its implication for the origin of mineral matter in coal

USGS Publications Warehouse

Neuzil, Sandra G.; Supardi,; Cecil, C. Blaine; Kane, Jean S.; Soedjono, Kadar

1993-01-01

The inorganic geochemistry of three domed ombrogenous peat deposits in Riau and West Kalimantan provinces, Indonesia, was investigated as a possible modern analogue for certain types of low-ash, low-sulfur coal. Mineral matter entering the deposits is apparently limited to small amounts from the allogenic sources of dryfall, rainfall, and diffusion from substrate pore water. In the low-ash peat in the interior of the deposits, a large portion of the mineral matter is authigenic and has been mobilized and stabilized by hydrological, chemical, and biological processes and conditions.Ash yield and sulfur content are low through most of the peat deposits and average 1.1% and 0.14%, respectively, on a moisture-free basis. Ash and sulfur contents only exceed 5% and 0.3%, respectively, near the base of the deposits, with maximum concentrations of 19.9% ash and 0.56% sulfur. Peat water in all three deposits has a low pH, about 4 units, and low dissolved cation concentration, averaging 14 ppm. Near the base, in the geographic interior of each peat deposit, pH is about two units higher and dissolved cation concentration averages 110 ppm. Relative concentrations of the inorganic constituents vary, resulting in chemical facies in the peat. In general, Si, Al, and Fe are the abundant inorganic constituents, although Mg, Ca, and Na dominate in the middle horizon in the geographic interior of coastal peat deposits.The composition of the three deposits reported in this paper indicates that domed ombrogenous peat deposits will result in low ash and sulfur coal, probably less than 10% ash and 1% sulfur, even if marine rocks are laterally and vertically adjacent to the coal.

Foam concrete of increased strength with the thermomodified peat additives

NASA Astrophysics Data System (ADS)

Kudyakov, A. I.; Kopanitsa, N. O.; Sarkisov, Ju S.; Kasatkina, A. V.; Prischepa, I. A.

2015-01-01

The paper presents the results of research of foam concrete with thermomodified peat additives. The aim of the research was to study the effect of modifying additives on cement stone and foam concrete properties. Peat additives are prepared by heat treatment of peat at 600 °C. Two approaches of obtaining additives are examined: in condition of open air access (TMT-600) and in condition of limited air access (TMT-600-k). Compressive strength of a cement stone with modifiers found to be increased by 28.9 - 65.2%. Introducing peat modifiers into foam concrete mix leads to increase of compressive strength by 44-57% at 28- day age and heat conductivity of foam concrete decreases by 0.089 W/(m·°C).

Alfred P. Dachnowski and the scientific study of peats

USGS Publications Warehouse

Landa, E.R.; Cohen, K.M.

2011-01-01

Botanist Alfred Paul Dachnowski (1875–1949) was a major contributor to efforts at mapping organic soils in the United States during the early 20th century. He began his career at The Ohio State University, and spent most of his professional life at the U.S. Department of Agriculture in Washington, DC. His work spanned a diversity of topics, including bog ecology and the ecosystem services provided by wetlands, the mapping and chemical characterization of peat, and the commercial applications of peat. We present a biography and overview of his work. Dachnowski is best known today for the peat sampler that bears his name. The details of its operation are described here, and its place in modern peat studies is discussed.

Peat fires as source of polycyclic aromatic hydrocarbons in soils

NASA Astrophysics Data System (ADS)

Tsibart, Anna

2013-04-01

Polycyclic aromatic hydrocarbons (PAHs) arrive from pyrogenic sources including volcanism and the combustion of oil products and plant materials. The production of PAHs during the combustion of plant materials was considered in a number of publications, but their results were mainly obtained in laboratory experiments. Insufficient data are available on the hightemperature production of PAHs in environmental objects. For example, natural fires are frequently related to the PAH sources in landscapes, but very little factual data are available on this topic. On Polistovskii reserve (Russia, Pskov region) the soil series were separated depending on the damage to the plants; these series included soils of plots subjected to fires of different intensities, as well as soils of the background plots. The series of organic and organomineral soils significantly differed in their PAH distributions. In this series, the concentration of PAHs in the upper horizons of the peat soils little varied or slightly decreased, but their accumulation occurred at a depth of 5-10 or 10-20 cm in the soils after the fires. For example, in the series of high moor soils, the content of PAHs in the upper horizons remained almost constant; significant differences were observed in the subsurface horizons: from 2 ng/g in the background soil to 70 ng/g after the fire. In the upper horizons of the oligotrophic peat soils under pine forests, the total PAH content also varied only slightly. At the same time, the content of PAHs in the soil series increased from 15 to 90 ng/g with the increasing pyrogenic damage to the plot. No clear trends of the PAH accumulation were recorded in the organomineral soils. The content of PAHs in the soddy-podzolic soil subjected to fire slightly decreased (from 20 to 10 ng/g) compared to the less damaged soil. In peat fires, the access of oxygen to the fire zone is lower than in forest fires. The oxygen deficit acts as a factor of the organic fragments recombination and PAH production; therefore, larger amounts of PAHs are formed in peat fires. In addition, the peat fires occur directly in the soil layer; therefore, larger amounts of the resulting polyarenes remain in the soils of the fire sites. PAHs also can be formed at the heating of organic matter on the areas adjacent to the fire sites. After the combustion of peat in fires, phenanthrene, chrysene, benz[a]pyrene, and tetraphene accumulate in soils. This is mainly the group of 4-nuclear compounds with the participation of 3-nuclear phenanthrene and 5-nuclear benz[a]pyrene. The formation of high-molecular weight compounds like benz[a]pyrene and, in some places, benzo[ghi]perylene is possible during smoldering under a low oxygen supply.

Volatile and semivolatile organic compounds in laboratory peat fire emissions

EPA Science Inventory

Speciated volatile organic compounds (VOCs) and organic fine particulate matter (PM2.5) mass emission factors were determined from laboratory peat fire experiments. Peat samples originated from two wildlife reserves located near the coast of North Carolina, U.S. Gas and particula...

The Challenge of Peat Substitution in Organic Seedling Production: Optimization of Growing Media Formulation through Mixture Design and Response Surface Analysis

PubMed Central

Ceglie, Francesco Giovanni; Bustamante, Maria Angeles; Ben Amara, Mouna; Tittarelli, Fabio

2015-01-01

Peat replacement is an increasing demand in containerized and transplant production, due to the environmental constraints associated to peat use. However, despite the wide information concerning the use of alternative materials as substrates, it is very complex to establish the best materials and mixtures. This work evaluates the use of mixture design and surface response methodology in a peat substitution experiment using two alternative materials (green compost and palm fibre trunk waste) for transplant production of tomato (Lycopersicon esculentum Mill.); melon, (Cucumis melo L.); and lettuce (Lactuca sativa L.) in organic farming conditions. In general, the substrates showed suitable properties for their use in seedling production, showing the best plant response the mixture of 20% green compost, 39% palm fibre and 31% peat. The mixture design and applied response surface methodology has shown to be an useful approach to optimize substrate formulations in peat substitution experiments to standardize plant responses. PMID:26070163

Degradation potentials of dissolved organic carbon (DOC) from thawed permafrost peat

PubMed Central

Panneer Selvam, Balathandayuthabani; Lapierre, Jean-François; Guillemette, Francois; Voigt, Carolina; Lamprecht, Richard E.; Biasi, Christina; Christensen, Torben R.; Martikainen, Pertti J.; Berggren, Martin

2017-01-01

Global warming can substantially affect the export of dissolved organic carbon (DOC) from peat-permafrost to aquatic systems. The direct degradability of such peat-derived DOC, however, is poorly constrained because previous permafrost thaw studies have mainly addressed mineral soil catchments or DOC pools that have already been processed in surface waters. We incubated peat cores from a palsa mire to compare an active layer and an experimentally thawed permafrost layer with regard to DOC composition and degradation potentials of pore water DOC. Our results show that DOC from the thawed permafrost layer had high initial degradation potentials compared with DOC from the active layer. In fact, the DOC that showed the highest bio- and photo-degradability, respectively, originated in the thawed permafrost layer. Our study sheds new light on the DOC composition of peat-permafrost directly upon thaw and suggests that past estimates of carbon-dioxide emissions from thawed peat permafrost may be biased as they have overlooked the initial mineralization potential of the exported DOC. PMID:28378792

Seasonal changes in peatland surface elevation recorded at GPS stations in the Red Lake Peatlands, northern Minnesota, USA

USGS Publications Warehouse

Reeve, A.S.; Glaser, P.H.; Rosenberry, Donald O.

2013-01-01

Northern peatlands appear to hold large volumes of free-phase gas (e.g., CH4 and CO2), which has been detected by surface deformations, pore pressure profiles, and electromagnetic surveys. Determining the gas content and its impact in peat is challenging because gas storage depends on both the elastic properties of the peat matrix and the buoyant forces exerted by pore fluids. We therefore used a viscoelastic deformation model to estimate these variables by adjusting model runs to reproduce observed changes in peat surface elevation within a 1300 km2 peatland. A local GPS network documented significant changes in surface elevations throughout the year with the greatest vertical displacements associated with rapid changes in peat water content and unloadings due to melting of the winter snowpack. These changes were coherent with changes in water table elevation and also abnormal pore pressure changes measured by nests of instrumented piezometers. The deformation model reproduced these changes when the gas content was adjusted to 10% of peat volume, and Young's modulus was varied between 5 and 100 kPa as the peat profile shifted from tension to compression. In contrast, the model predicted little peat deformation when the gas content was 3% or lower. These model simulations are consistent with previous estimates of gas volume in northern peatlands and suggest an upper limit of gas storage controlled by the elastic moduli of the peat fabric.

Net ecosystem CO2 exchange of a primary tropical peat swamp forest in Sarawak, Malaysia

NASA Astrophysics Data System (ADS)

Tang Che Ing, A.; Stoy, P. C.; Melling, L.

2014-12-01

Tropical peat swamp forests are widely recognized as one of the world's most efficient ecosystems for the sequestration and storage of carbon through both their aboveground biomass and underlying thick deposits of peat. As the peat characteristics exhibit high spatial and temporal variability as well as the structural and functional complexity of forests, tropical peat ecosystems can act naturally as both carbon sinks and sources over their life cycles. Nonetheless, few reports of studies on the ecosystem-scale CO2 exchange of tropical peat swamp forests are available to-date and their present roles in the global carbon cycle remain uncertain. To quantify CO2 exchange and unravel the prevailing factors and potential underlying mechanism regulating net CO2 fluxes, an eddy covariance tower was erected in a tropical peat swamp forest in Sarawak, Malaysia. We observed that the diurnal and seasonal patterns of net ecosystem CO2 exchange (NEE) and its components (gross primary productivity (GPP) and ecosystem respiration (RE)) varied between seasons and years. Rates of NEE declined in the wet season relative to the dry season. Conversely, both the gross primary productivity (GPP) and ecosystem respiration (RE) were found to be higher during the wet season than the dry season, in which GPP was strongly negatively correlated with NEE. The average annual NEE was 385 ± 74 g C m-2 yr-1, indicating the primary peat swamp forest functioned as net source of CO2 to the atmosphere over the observation period.

Using pheromones to protect heat-injured lodgepole pine from mountain pine beetle infestation

Treesearch

Gene D. Amman; Kevin C. Ryan

1994-01-01

The bark beetle antiaggregative pheromones, verbenone and ipsdienol, were tested in protecting heat-injured lodgepole pine (Pinus contorta Dougl. ex Loud.) from mountain pine beetle (Dendroctonus ponderosae Hopkins) infestation in the Sawtooth National Recreation Area in central Idaho. Peat moss was placed around 70 percent of the...

Peat landforms along the Albany River, northern Ontario. An ecological study of peat landforms in Canada and Alaska

NASA Technical Reports Server (NTRS)

Glaser, P. H.

1985-01-01

During the summer of 1985 a field investigation was started in the Hudson Bay lowland region of northern Ontario, which represents the largest expanse of peatland in North America and is an important sink in the global carbon cycle. A key area in the lowlands is situated along the Albany River near the confluence of the Chepay River. Here the striking vegetation-landforms are transitional between those found on the bed of Glacial Lake Agassiz in northern Minnesota and southern Manitoba and the more northern peatlands in the Hudson Bay lowland region. In peatland studies elsewhere the landform patterns have been used not only to classify different peatland types but also as an indicator of potential developmetnal trends. The study area is generally defined by that covered by the TM scene E-40062-15532 taken on Sept. 16, 1982. The purpose of the field work is to acquire sufficent information to interpret the TM imagery and test various hypotheses on peatland development on the gasis of the pattern transitions.

Sulfur variability and petrology of the Lower Block Coal Member (Pennsylvanian) in Southwest Indiana

USGS Publications Warehouse

Padgett, P.L.; Rimmer, S.M.; Ferm, J.C.; Hower, J.C.; Eble, C.F.; Mastalerz, Maria

1999-01-01

The Lower Block Coal Member (Pennsylvanian-Atokan, Westphalian C) is an economic low-to medium-sulfur, low-ash coal resource in the Illinois Basin. Sulfur content is generally low (averaging 1.0%) in the study area, but varies over short distances. Higher sulfur areas occur as isolated pods and epigenetic pyrite increases significantly in the upper third of the selected columns in higher sulfur areas. Sulfur variations cannot be predicted by typical geologic characteristics such as roof lithology, seam thickness, or seam elevation. Petrographic analysis shows that pyrite is generally associated with brighter microlithotypes, except in higher sulfur areas where infilling pyrite forms are associated with inertite. Higher sulfur areas reflect the water chemistry of the paleomire during and shortly after peat accumulation. Locally, abundant pyrofusinite provided additional pore space for pyrite precipitation.The Lower Block Coal Member (Pennsylvanian-Atokan, Westphalian C) is an economic low- to medium-sulfur, low-ash coal resource in the Illinois Basin. Sulfur content is generally low (averaging 1.0%) in the study area, but varies over short distances. Higher sulfur areas occur as isolated pods and epigenetic pyrite increases significantly in the upper third of the selected columns in higher sulfur areas. Sulfur variations cannot be predicted by typical geologic characteristics such as roof lithology, seam thickness, or seam elevation. Petrographic analysis shows that pyrite is generally associated with brighter microlithotypes, except in higher sulfur areas where infilling pyrite forms are associated with inertite. Higher sulfur areas reflect the water chemistry of the paleomire during and shortly after peat accumulation. Locally, abundant pyrofusinite provided additional pore space for pyrite precipitation.

Mapping SOC content and bulk density of a disturbed peatland relict with electromagnetic induction and DEM data

NASA Astrophysics Data System (ADS)

Altdorff, Daniel; Bechtold, Michel; van der Kruk, Jan; Tiemeyer, Bärbel; von Hebel, Christian; Huisman, Johan Alexander

2014-05-01

Peatlands represent a huge storage of soil organic carbon (SOC), and there is considerable interest to assess the total amount of carbon stored in these ecosystems. However, reliable field-scale information about peat properties, particularly SOC content and bulk density (BD) necessary to estimate C stocks, remains difficult to obtain. A potential way to acquire information on these properties and its spatial variation is the non-invasive mapping of easily recordable physical variables that correlate with peat properties, such as bulk electrical conductivity (ECa) measured with electromagnetic induction (EMI). However, ECa depends on a range of soil properties, including BD, soil and water chemistry, and water content, and thus results often show complex and site-specific relationships. Therefore, a reliable prediction of SOC and BD from ECa data is not necessarily given. In this study, we aim to explore the usefulness of Multiple Linear Regression (MLR) models to predict the peat soil properties SOC and BD from multi-offset EMI and high-resolution DEM data. The quality of the MLR models is assessed by cross-validation. We use data from a medium-scale disturbed peat relict (approximately 35ha) in Northern Germany. The potential explanatory variables considered in MLR were: EMI data of six different integral depths (approximately 0.25, 0.5, 0.6, 0.9, 1, and 1.80 m), their vertical heterogeneity, as well as several topographical variables extracted from the DEM. Ground truth information for SOC, BD content and peat layer thickness was obtained from 34 soil cores of 1 m depth. Each core was divided into several 5 to 20 cm thick layers so that integral information of the upper 0.25, 0.5, and 1 m as well as from the total peat layer was obtained. For cross-validation of results, we clustered the 34 soil cores into 4 classes using K-means clustering and selected 8 cores for validation from the clusters with a probability that depended on the size of the cluster. With the remaining 26 samples, we performed a stepwise MLR and generated separate models for each depth and soil property. Preliminary results indicate reliable model predictions for SOC and BD (R² = 0.83- 0.95). The RMSE values of the validation ranged between 3.5 and 7.2 vol. % for SOC and 0.13 and 0.37 g/cm³ for BD for the independent samples. This equates roughly the quality of SOC predictions obtained by field application of vis-NIR (visible-near infrared) presented in literature for a similar peatland setting. However, the EMI approach offers the potential to derive information from deeper depths and allows non-invasive mapping of BD variability, which is not possible with vis-NIR. Therefore, this new approach potentially provides a more useful tool for total carbon stock assessment in peatlands.

AmeriFlux US-Snd Sherman Island

DOE Data Explorer

Baldocchi, Dennis [University of California, Berkeley

2016-01-01

This is the AmeriFlux version of the carbon flux data for the site US-Snd Sherman Island. Site Description - The Sherman Island site is a 38-ha peatland pasture, west of the Delta, that is owned by the state and managed by the California Department of Water Resources. The site is degraded and heavily grazed with ~100 cattle in the area that circumscribes the main field and fetch. The island has been drained and farmed since the late 1800s. The soils of the Delta overlay deep peat that was sequestered over the Holocene period as sea-level rose and flooding of archaic wetlands prevented decomposition of roots and stems. Hence, the upper 10 m of peatland has been lost to decomposition, compaction, and subsidence. Today a mineral soil overlays a peat layer, which coincides with the general depth of the water table.

Comparison of pelletized biochar derived from two source materials as replacements for peat in potting substrates

USDA-ARS?s Scientific Manuscript database

Soilless substrates are primarily used in the production of containerized greenhouse and nursery crops, with sphagnum peat moss being a primary constituent of most substrates. We are examining biochars for several horticultural applications, including as peat moss replacements. Biochar was prepared ...

Development of a Palliative Education Assessment Tool for Medical Student Education.

ERIC Educational Resources Information Center

Meekin, Sharon Abele; Klein, Jason E.; Fleischman, Alan R.; Fins, Joseph J.

2000-01-01

Describes the Palliative Education Assessment Tool (PEAT), an innovative assessment to facilitate curricular mapping of palliative care education. The PEAT comprises seven palliative care domains, each of which details specific objectives of knowledge, skills, and attitudes. PEAT enables educators to describe a specific multidimensional aspect of…

Posidonia oceanica (L.) based compost as substrate for potted basil production.

PubMed

Mininni, Carlo; Grassi, Francesco; Traversa, Andreina; Cocozza, Claudio; Parente, Angelo; Miano, Teodoro; Santamaria, Pietro

2015-08-15

Peat is the main component of growing media but is also a non-renewable resource; therefore European policy strongly encourages the use of peat alternatives such as compost. Posidonia is a Mediterranean seagrass that produces very conspicuous onshore deposits that can be composted. In this study, a commercial green compost and a Posidonia residue-based compost were tested in order to assess their potential use as substitutes or complements to peat. All macro and micro-element concentrations of the substrates were positively and significantly related to the percentage of composts in the growing media. Plant grown on peat showed higher content of P, Ca, K, Na, Cu, Mn, Zn and Fe, and a slightly higher biomass production in comparison to compost-based growing media. In contrast, plants grown on compost-based substrates showed lower uptake of Cd and Cr than peat. The results indicate that both composts can be used as a complement to the peat for substrate preparation, especially at a rate of 30%. The Posidonia-based compost showed better productive results in comparison to the green one. Basil grown on the two compost-based media showed reduced absorption level of potentially toxic metals in comparison to peat. © 2014 Society of Chemical Industry.

Stable carbon and nitrogen isotopes in vertical peat profiles of natural and drained boreal peatlands

NASA Astrophysics Data System (ADS)

Nykänen, Hannu; Mpamah, Promise; Rissanen, Antti; Pitkänen, Aki; Turunen, Jukka; Simola, Heikki

2015-04-01

Peatlands form a significant carbon pool in the global carbon cycle. Change in peat hydrology, due to global warming is projected to change microbiological processes and peat carbon pool. We tested if bulk stable carbon and nitrogen isotopes serve as indicators of severe long term drying in peatlands drained for forestry. Depth profile analysis of peat, for their carbon and nitrogen content as well as their carbon and nitrogen stable isotopic signatures, were conducted for peatlands in southern and eastern Finland, having ombrotrophic and minerotrophic natural and corresponding drained pairs or separate drained sites. The selection of sites allowed us to compare changes due to different fertility and changes due to long term artificial drying. Drainage lasting over 40 years has led to changes in hydrology, vegetation, nutrient mineralization and respiration. Furthermore, increased nutrient uptake and possible recycling of peat nitrogen and carbon trough vegetation back to the peat surface, also possibly has an effect on the stable isotopic composition of peat carbon and nitrogen. We think that drainage induced changes somehow correspond to those caused by changed hydrology due to climate change. We will present data from these measurements and discuss their implications for carbon and nitrogen flows in peatlands.

Saprophytic and Potentially Pathogenic Fusarium Species from Peat Soil in Perak and Pahang

PubMed Central

Karim, Nurul Farah Abdul; Mohd, Masratulhawa; Nor, Nik Mohd Izham Mohd; Zakaria, Latiffah

2016-01-01

Isolates of Fusarium were discovered in peat soil samples collected from peat swamp forest, waterlogged peat soil, and peat soil from oil palm plantations. Morphological characteristics were used to tentatively identify the isolates, and species confirmation was based on the sequence of translation elongation factor-1α (TEF-1α) and phylogenetic analysis. Based on the closest match of Basic Local Alignment Search Tool (BLAST) searches against the GenBank and Fusarium-ID databases, five Fusarium species were identified, namely F. oxysporum (60%), F. solani (23%), F. proliferatum (14%), F. semitectum (1%), and F. verticillioides (1%). From a neighbour-joining tree of combined TEF-1α and β-tubulin sequences, isolates from the same species were clustered in the same clade, though intraspecies variations were observed from the phylogenetic analysis. The Fusarium species isolated in the present study are soil inhabitants and are widely distributed worldwide. These species can act as saprophytes and decomposers as well as plant pathogens. The presence of Fusarium species in peat soils suggested that peat soils could be a reservoir of plant pathogens, as well-known plant pathogenic species such F. oxysporum, F. solani, F. proliferatum, and F. verticillioides were identified. The results of the present study provide knowledge on the survival and distribution of Fusarium species. PMID:27019679

Sequestration of arsenic in ombrotrophic peatlands

NASA Astrophysics Data System (ADS)

Rothwell, James; Hudson-Edwards, Karen; Taylor, Kevin; Polya, David; Evans, Martin; Allott, Tim

2014-05-01

Peatlands can be important stores of arsenic but we are lacking spectroscopic evidence of the sequestration pathways of this toxic metalloid in peatland environments. This study reports on the solid-phase speciation of anthropogenically-derived arsenic in atmospherically contaminated peat from the Peak District National Park (UK). Surface and sub-surface peat samples were analysed by synchrotron X-ray absorption spectroscopy on B18 beamline at Diamond Light Source (UK). The results suggest that there are contrasting arsenic sequestration mechanisms in the peat. The bulk arsenic speciation results, in combination with strong arsenic-iron correlations at the surface, suggest that iron (hydr)oxides are key phases for the immobilisation of arsenic at the peat surface. In contrast, the deeper peat samples are dominated by arsenic sulphides (arsenopyrite, realgar and orpiment). Given that these peats receive inputs solely from the atmosphere, the presence of these sulphide phases suggests an in-situ authigenic formation. Redox oscillations in the peat due to a fluctuating water table and an abundant store of legacy sulphur from historic acid rain inputs may favour the precipitation of arsenic sequestering sulphides in sub-surface horizons. Oxidation-induced loss of these arsenic sequestering sulphur species by water table drawdown has important implications for the mobility of arsenic and the quality of waters draining peatlands.

Resilient modulus characteristics of soil subgrade with geopolymer additive in peat

NASA Astrophysics Data System (ADS)

Zain, Nasuhi; Hadiwardoyo, Sigit Pranowo; Rahayu, Wiwik

2017-06-01

Resilient modulus characteristics of peat soil are generally very low with high potential of deformation and low bearing capacity. The efforts to improve the peat subgrade resilient modulus characteristics is required, one among them is by adding the geopolymer additive. Geopolymer was made as an alternative to replace portland cement binder in the concrete mix in order to promote environmentally friendly, low shrinkage value, low creep value, and fire resistant material. The use of geopolymer to improve the mechanical properties of peat as a road construction subgrade, hence it becomes important to identify the effect of geopolymer addition on the resilient modulus characteristics of peat soil. This study investigated the addition of 0% - 20% geopolymer content on peat soil derived from Ogan Komering Ilir, South Sumatera Province. Resilient modulus measurement was performed by using cyclic triaxial test to determine the resilience modulus model as a function of deviator stresses and radial stresses. The test results showed that an increase in radial stresses did not necessarily lead to an increase in modulus resilient, and on the contrary, an increase in deviator stresses led to a decrease in modulus resilient. The addition of geopolymer in peat soil provided an insignificant effect on the increase of resilient modulus value.

How does whole ecosystem warming of a peatland affect methane production and consumption?

NASA Astrophysics Data System (ADS)

Hopple, A.; Brunik, K.; Keller, J.; Pfeifer-Meister, L.; Woerndle, G.; Zalman, C.; Hanson, P.; Bridgham, S. D.

2017-12-01

Peatlands are among Earth's most important terrestrial ecosystems due to their massive soil carbon (C) stores and significant release of methane (CH4) into the atmosphere. Methane has a sustained-flux global warming potential 45-times greater than carbon dioxide (CO2), and the accuracy of Earth system model projections relies on our mechanistic understanding of peatland CH4 cycling in the context of environmental change. The objective of this study was to determine, under in situ conditions, how heating of the peat profile affects ecosystem-level anaerobic C cycling. We assessed the response of CO2 and CH4 production, as well as the anaerobic oxidation of CH4 (AOM), in a boreal peatland following 13 months of deep peat heating (DPH) and 16 months of subsequent whole-ecosystem warming (surface and deep heating; WEW) as part of the Spruce and Peatland Responses Under Changing Environments (SPRUCE) project in northern Minnesota, USA. The study uses a regression-based experimental design including 5 temperature treatments that warmed the entire 2 m peat profile from 0 to +9 °C above ambient temperature. Soil cores were collected at multiple depths (25-200 cm) from each experimental chamber at the SPRUCE site and anaerobically incubated at in situ temperatures for 1-2 weeks. Methane and CO2 production in surface peat were positively correlated with elevated temperature, but no consistent temperature response was found at depth (75-200 cm) following DPH. However, during WEW, we observed significant increases in both surface and deep peat methanogenesis with increasing temperature. Surface peat had greater CH4 production rates than deeper peat, implying that the increased CH4 emissions observed in the field were largely driven by surface peat warming. The CO2:CH4 ratio was inversely correlated with temperature across all depths following 16 months of WEW, indicating that the entire peat profile is becoming more methanogenic with warming. We also observed AOM throughout the whole peat profile, with the highest rates observed at the surface and initial data suggesting a positive correlation with increasing temperature. While SPRUCE will continue for many years, our initial results suggest that the vast C stores at depth in peatlands are minimally responsive to warming and any response will be driven largely by surface peat.

Effect of Different Peat Size and Pre-Consolidation Pressure of Reconstituted Peat on Effective Undrained Shear Strength Properties

NASA Astrophysics Data System (ADS)

Azhar, ATS; Norhaliza, W.; Ismail, B.; Ezree, AM; Nizam, ZM

2017-08-01

Shear strength of the soil is one of the most important parameters in engineering design, especially during the pre- or post-construction periods, since it is mainly used to measure and evaluate the foundation or slope stability of soil. Peat normally known as a soil that has a very low value of shear strength, and in order to determine and understand the shear strength of the peat, it is a difficult task in geotechnical engineering due to several factors such as types of fabrics, the origin of the soil, water content, organic matter and the degree of humification. The aim of this study is to determine the effective undrained shear strength properties of reconstituted peat of different sizes. All the reconstituted peat samples were formed with the size that passed the opening sieve of 0.425 mm (

Population density of red langurs in Sabangau tropical peat-swamp forest, Central Kalimantan, Indonesia.

PubMed

Ehlers Smith, David A; Ehlers Smith, Yvette C

2013-08-01

Because of the large-scale destruction of Borneo's rainforests on mineral soils, tropical peat-swamp forests (TPSFs) are increasingly essential for conserving remnant biodiversity, particularly in the lowlands where the majority of habitat conversion has occurred. Consequently, effective strategies for biodiversity conservation are required, which rely on accurate population density and distribution estimates as a baseline. We sought to establish the first population density estimates of the endemic red langur (Presbytis rubicunda) in Sabangau TPSF, the largest remaining contiguous lowland forest-block on Borneo. Using Distance sampling principles, we conducted line transect surveys in two of Sabangau's three principle habitat sub-classes and calculated group density at 2.52 groups km⁻² (95% CI 1.56-4.08) in the mixed-swamp forest sub-class. Based on an average recorded group size of 6.95 individuals, population density was 17.51 ind km⁻², the second highest density recorded in this species. The accessible area of the tall-interior forest, however, was too disturbed to yield density estimates representative of the entire sub-class, and P. rubicunda was absent from the low-pole forest, likely as a result of the low availability of the species' preferred foods. This absence in 30% of Sabangau's total area indicates the importance of in situ population surveys at the habitat-specific level for accurately informing conservation strategies. We highlight the conservation value of TPSFs for P. rubicunda given the high population density and large areas remaining, and recommend 1) quantifying the response of P. rubicunda to the logging and burning of its habitats; 2) surveying degraded TPSFs for viable populations, and 3) effectively delineating TPSF sub-class boundaries from remote imagery to facilitate population estimates across the wider peat landscape, given the stark contrast in densities found across the habitat sub-classes of Sabangau. © 2013 Wiley Periodicals, Inc.

Effects of Unsaturated Microtopography on Nitrate Concentrations in Tundra Ecosystems: Examples from Polygonal Terrain and Degraded Peat Plateaus

NASA Astrophysics Data System (ADS)

Heikoop, J. M.; Arendt, C. A.; Newman, B. D.; Charsley-Groffman, L.; Perkins, G.; Wilson, C. J.; Wullschleger, S.

2017-12-01

Under the auspices of the Next Generation Ecosystem Experiment - Arctic, we have been studying hydrogeochemical signals in Alaskan tundra ecosystems underlain by continuous permafrost (Barrow Environmental Observatory (BEO)) and discontinuous permafrost (Seward Peninsula). The Barrow site comprises largely saturated tundra associated with the low gradient Arctic Coastal Plain. Polygonal microtopography, however, can result in slightly raised areas that are unsaturated. In these areas we have previously demonstrated production and accumulation of nitrate, which, based on nitrate isotopic analysis, derives from microbial degradation. Our Seward Peninsula site is located in a much steeper and generally well-drained watershed. In lower-gradient areas at the top and bottom of the watershed, however, the tundra is generally saturated, likely because of the presence of underlying discontinuous permafrost inhibiting infiltration. These settings also contain microtopographic features, though in the form of degraded peat plateaus surrounded by wet graminoid sag ponds. Despite being very different microtopographic features in a very different setting with distinct vegetation, qualitatively similar nitrate accumulation patterns as seen in polygonal terrain were observed. The highest nitrate pore water concentration observed in an unsaturated peat plateau was approximately 5 mg/L, whereas subsurface pore water concentrations in surrounding sag ponds were generally below the limit of detection. Nitrate isotopes indicate this nitrate results from microbial mineralization and nitrification based on comparison to the nitrate isotopic composition of reduced nitrogen sources in the environment and the oxygen isotope composition of site pore water. Nitrate concentrations were most similar to those found in low-center polygon rims and flat-centered polygon centers at the BEO, but were significantly lower than the maximum concentrations seen in the highest and driest polygonal features, the centers of high-centered polygons. Combined, these results suggest that moisture content is a significant control on nitrate production and accumulation in tundra ecosystems and that unsaturated microtopography represents hot spots for microbial decomposition.

The effects of lead sources on oral bioaccessibility in soil and implications for contaminated land risk management.

PubMed

Palmer, Sherry; McIlwaine, Rebekka; Ofterdinger, Ulrich; Cox, Siobhan F; McKinley, Jennifer M; Doherty, Rory; Wragg, Joanna; Cave, Mark

2015-03-01

Lead (Pb) is a non-threshold toxin capable of inducing toxic effects at any blood level but availability of soil screening criteria for assessing potential health risks is limited. The oral bioaccessibility of Pb in 163 soil samples was attributed to sources through solubility estimation and domain identification. Samples were extracted following the Unified BARGE Method. Urban, mineralisation, peat and granite domains accounted for elevated Pb concentrations compared to rural samples. High Pb solubility explained moderate-high gastric (G) bioaccessible fractions throughout the study area. Higher maximum G concentrations were measured in urban (97.6 mg kg(-1)) and mineralisation (199.8 mg kg(-1)) domains. Higher average G concentrations occurred in mineralisation (36.4 mg kg(-1)) and granite (36.0 mg kg(-1)) domains. Findings suggest diffuse anthropogenic and widespread geogenic contamination could be capable of presenting health risks, having implications for land management decisions in jurisdictions where guidance advises these forms of pollution should not be regarded as contaminated land. Copyright © 2015 Elsevier Ltd. All rights reserved.

Impacts of past climate and sea level change on Everglades wetlands: placing a century of anthropogenic change into a late-Holocene context

USGS Publications Warehouse

Willard, D.A.; Bernhardt, C.E.

2011-01-01

We synthesize existing evidence on the ecological history of the Florida Everglades since its inception ~7 ka (calibrated kiloannum) and evaluate the relative impacts of sea level rise, climate variability, and human alteration of Everglades hydrology on wetland plant communities. Initial freshwater peat accumulation began between 6 and 7 ka on the platform underlying modern Florida Bay when sea level was ~6.2 m below its current position. By 5 ka, sawgrass and waterlily peats covered the area bounded by Lake Okeechobee to the north and the Florida Keys to the south. Slower rates of relative sea level rise ~3 ka stabilized the south Florida coastline and initiated transitions from freshwater to mangrove peats near the coast. Hydrologic changes in freshwater marshes also are indicated ~3 ka. During the last ~2 ka, the Everglades wetland was affected by a series of hydrologic fluctuations related to regional to global-scale fluctuations in climate and sea level. Pollen evidence indicates that regional-scale droughts lasting two to four centuries occurred ~1 ka and ~0.4 ka, altering wetland community composition and triggering development of characteristic Everglades habitats such as sawgrass ridges and tree islands. Intercalation of mangrove peats with estuarine muds ~1 ka indicates a temporary slowing or stillstand of sea level. Although sustained droughts and Holocene sea level rise played large roles in structuring the greater Everglades ecosystem, twentieth century reductions in freshwater flow, compartmentalization of the wetland, and accelerated rates of sea level rise had unprecedented impacts on oxidation and subsidence of organic soils, changes/loss of key Everglades habitats, and altered distribution of coastal vegetation.

Late Holocene Permafrost Aggradation in the Western Kenai Lowlands, Alaska: Implications for Climate Reconstruction and Carbon Cycling.

NASA Astrophysics Data System (ADS)

Hoefke, K.; Jones, M.; Jones, B. M.

2017-12-01

Rapid permafrost thaw is occurring throughout the permafrost zone, particularly at the southern margins, where mean annual air temperatures are above 0°C. As the Kenai lowlands experience ecosystem shifts due to human disturbance and climate change, understanding permafrost history is of particular interest given the direct impacts on hydrology, vegetation, and carbon cycling. Across the northern high latitudes, permafrost peatlands within the sporadic and isolated permafrost zone store 95 Pg of C and permafrost formation processes (i.e., syngenetic versus epigenetic) are thought to influence the degree of carbon loss following thaw. This study uses plant macrofossils and radiocarbon dating to determine the timing of permafrost aggradation of a recently-thawed (since 1950 CE) peatland located directly adjacent to a 5-meter thick permafrost plateau landform in the Kenai Peninsula lowlands in south-central Alaska. The coring site was selected using remote sensing imagery to identify areas where permafrost plateaus have been thawing since 1950 CE. Preliminary results show dominance of brown moss (Paludella squarrosa, Drepanocladus spp., Tomenthypnum nitens) and sedge (Carex spp.) from peat inception 11,700 cal yr BP to 3,000 cal yr BP indicative of a permafrost-free rich fen. A transition to silvic peat (Betula nana, Vaccinium oxycoccus, Ledum groenlandicum, ericaceous shrub macrofossils) 3,000 cal yr BP (indicates that permafrost aggradation coincided with neoglacial cooling. Since permafrost aggraded 9000 years after peat accumulation began and permafrost deepened to 5 m into unfrozen peat, this suggests mean annual air temperatures decreased significantly below 0ºC for several millennia in the late Holocene on the Kenai lowlands. This study will also examine impacts of permafrost aggradation and degradation on rates of carbon accumulation and loss.

Holocene sedimentation at Corkscrew Swamp (Collier Co. ): A model for the origin and evolution of the present wetland-dominated regime of south Florida

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stone, P.A.; Duever, M.J.; Meeder, J.F.

1993-03-01

A two-layer peat-over-marl (calcitic mud) sequence characterizes Corkscrew Swamp, a swamp/marsh complex in northern Big Cypress Swamp. The marl began depositing about 10,600 BP and based upon the regional modern analog represents a marsh (grassy) environment of relatively short seasonal flooding, rather than a marl lake. The marsh succeeded formerly dry land of full-glacial times on a long-emerged marine-sand and limestone peninsula. About 5,700 BP peat deposition began by the development of longer-flooded wetland, either marsh or woody swamp vegetation. Both shifts (Pleistocene/Holocene and mid-Holocene) represent onsets of wetter conditions, either episodically or by slowly passing critical thresholds, under controlmore » of climate and sea level (hydrologic baselevel). With the rise in average water level at and following each shift, in part by feedback from sediment infilling of the shallow (ca. 2.5m) mineral-substrate basin, the wetland and its deposit expanded upslope, both vertically and outward. A younger basal-peat date (3,900 BP) occurs toward the periphery. Some local topographic alteration by peat fire about 500 BP persists and affects the modern swamp vegetation. A wide swamp-to-marsh shift in other parts may have a similar cause. The shorter record yet revealed for the northern Everglades shows the same two-stage sequence, similar timing in peatland development, wetland and sediment expansion, and long-term (but there different) influences of local peatland topographic alteration. Many wetland areas in South Florida data from a mid-Holocene shift (7,000--4,000 BP).« less

Paleoenvironmental History of JoCo Marsh, Jamaica Bay, New York

NASA Technical Reports Server (NTRS)

Liberman, Louisa; Peteet, Dorothy; Hansen, James E. (Technical Monitor)

2001-01-01

Sediment cores from JoCo Marsh, located in Jamaica Bay, NY were analyzed for plant macrofossil and foraminifera records. These records reflect changes in vegetation, sea level, climate and human intervention. Better understanding of past environmental changes provides information for future preservation and protection of the estuary. A 2.81 m core was retrieved from JoCo, a high marsh area located on the eastern side of Jamaica Bay. The lithology of the core differs from high levels of sand, with small amounts of clay, in the bottom 0.8 meters, to salt marsh peat in the upper 2 meters of the core. Basal wood in the sand was dated to about 2060 yr BP. Elphidium foraminifera dominate the basal sands, along with Scirpus seeds, wood, and charcoal. These sands include fish scales which are tentatively identified as killifish, suggesting shallow pools. The transition to marsh peat is dominated by sedge seeds, and declines in charcoal. The peat appears to be dominated by salt marsh grasses. At 2 m the foraminifera change to include mainly Trochammina species and other undifferentiated agglutinates. The upper portion of the core is dominated by Salicornia seeds along with Trochammina and Miliammina or Quinqueloculia. The history of this marsh will be integrated with other records of marsh environmental change along the US eastern seaboard.

N cycling in SPRUCE (Spruce Peatlands Response Under ...

EPA Pesticide Factsheets

Peatlands located in boreal regions make up a third of global wetland area and are expected to have the highest temperature increases in response to climate change. As climate warms, we expect peat decomposition may accelerate, altering the cycling of nitrogen. Alterations in the nitrogen cycle can have consequences on NO3, NH4 availability or pollution, and potentially increase nitrous oxide (N2O) emissions, a persistent greenhouse gas (GHG). These consequences can cascade to altering whole ecosystem functions and effecting human health.We are investigating nitrogen cycling response to elevated temperature and CO2 in a boreal peatland. Spruce and Peatland Responses Under Climate and Environmental Change (SPRUCE) project initiated soil warming in 2014 in ten peatland mesocosms (five temperature treatments from ambient (+0°C) to +9°C) and elevated CO2 in half of the mesocosms in 2016. Peat cores at three depths (acrotelm, catotelm, deep peat) were analyzed in the laboratory for denitrification, nitrification, and ammonification. We expect denitrification, nitrification, and ammonification rates to increase, and denitrification efficiency to decrease with rising temperatures- potentially contaminating water resources with NO3, NH4 and increase N2O concentrations in our atmosphere. This research will enhance the scientific understanding of how nitrogen cycling, an important functional eco-service, responds under environmental conditions including elevated CO2

Chemical properties of peat used in balneology

NASA Astrophysics Data System (ADS)

Szajdak, L.; Hładoń, T.

2009-04-01

The physiological activity of peats is observed in human peat-bath therapy and in the promotion of growth in some plants. Balneological peat as an ecologically clean and natural substance is perceived as being more 'human friendly' than synthetic compounds. Poland has a long tradition of using balneological peat for therapeutic purposes. Balneological peat reveals a physical effect by altering temperature and biochemical effects through biologically active substances. It is mainly used for the treatment of rheumatic diseases that are quite common in Poland. Peat represents natural product. Physico-chemical properties of peat in particular surface-active, sorption and ion exchanges, defining their biological function, depend mainly on the chemical composition and molecular structure of humic substances representing the major constituent of organic soil (peat). The carbon of organic matter of peats is composed of 10 to 20% carbohydrates, primarily of microbial origin; 20% nitrogen-containing constituents, such as amino acids and amino sugars; 10 to 20% aliphatic fatty acids, alkanes, etc.; with the rest of carbon being aromatic. For balneology peat should be highly decomposed (preferably H8), natural and clean. The content of humic acids should exceed 20% of dry weight, ash content will be less than 15 15% of dry weight, sulphur content less than 0.3% of dry weight and the amount of water more than 85%. It will not contain harmful bacteria and heavy metals. Humic substances (HS) of peat are known to be macromolecular polydisperse biphyllic systems including both hydrophobic domains (saturated hydrocarbon chains, aromatic structural units) and hydrophilic functional groups, i. e having amphiphilic character. Amphiphilic properties of FA are responsible for their solubility, viscosity, conformation, surfactant-like character and a variety of physicochemical properties of considerable biologically practical significance. The chemical composition of peats depends significantly on the genesis of peatlands and the depth of sampling. The chemical properties of peat fulvic acids (FA) have some genetic peculiarities due to the specific conditions of the process of humification of peat-forming plants in mires. The process of humification in mires takes place in the top-forming layer under amphibious moisture conditions. Substances of microbial origin are water-soluble and can participate in the formation of peat FA to a little extent. So a main source of structural units for the peat HA and FA is suggested to be organic constituents of peat forming plants of various botanical composition. The content of aromatic units in peat FA was shown to depend on the content of lignin in peat-forming plants and also of the aromatization of polysaccharides mainly due to the transformation of cellulose. FA characterized lower than humic acids molecular weight (1000-30,000). FA's are composed of a series of highly oxidized aromatic rings with a large number of side chains. Building blocks are benzene carboxylic acids and phenolic acids. These are held together by hydrogen bonding van der Waals' forces and ionic bonding. FA contains larger concentrations of nitrogen. This fraction also contains a great deal of polysaccharide materials, as well as low molecular fatty acids and cytoplasmic constituents of microorganisms. These compounds are linear, flexible colloids at low concentrations, and spherical colloids at high solution concentrations and low pH values. A more adequate knowledge of the chemical structure of humic materials will assist us in better understanding the physiological effects and also the function of these macromolecules on the health that these materials are know to exert. This improved knowledge provides us better information on chemical structure of humic substances from peats, which are responsible for pharmacotherapeutic, pharmacokinetic and biopharmaceutical effect. This structure of FA creates proper conditions for uptake of nutrient as well as bioavailability of biologically active substances. The solubilization in water by humic materials of organic substances which are otherwise water-insoluble is a matter of considerable interest to chemist deals with the problem of the function of organic matter. There has been considerable evidence that humic substances can "complex" with several biologically active substances and so modify their physiological activity. It has been noteworthy that FA can "fix" high-molecular weight water-insoluble organic compounds and make them water-soluble. FA may so act as a vehicle for the mobilization, transport and immobilization of such substances in physiological conditions. Analysis of HA and FA carried out by several analytical methods revealed that there were no chemical interaction among biologically active substances but that latter was firmly adsorbed, possible by hydrogen-bonding, on the FA surfaces. Amino acids account for the majority of organic N fraction in humic substances. Most of the amino acids in organic matter occur in bound form in the humino-peptides fraction. These amino acids are commonly bound to the central core of FA. These humino-peptides fraction of FA mediate in respiration and act as hydrogen acceptors, thus affecting oxidation-reaction reactions. Thus, what is needed at this time is more fundamental research in order to solve practical pharmacological, pharmacokinetic and biopharmaceutical problem of great significance for human health.

Effect of mixing geopolymer and peat on bearing capacity in Ogan Komering Ilir (OKI) by California bearing ratio (CBR) test

NASA Astrophysics Data System (ADS)

Raharja, Danang S.; Hadiwardoyo, Sigit P.; Rahayu, Wiwik; Zain, Nasuhi

2017-06-01

Geopolymer is binder material that consists of solid material and the activator solution. Geopolymer material has successfully replaced cement in the manufacture of concrete with aluminosilicate bonding system. Geopolymer concrete has properties similar to cement concrete with high compressive strength, low shrinkage value, relatively low creep value, as well as acid-resistant. Based on these, the addition of polymers in peat soils is expected to improve the bearing capacity of peat soils. A study on the influence of geopolymer addition in peat soils was done by comparing before and after the peat soil was mixed with geopolymer using CBR (California Bearing Ratio) test in unsoaked and soaked conditions. 10% mixture content of the peat dry was used, weighted with a variety of curing time 4 hours, 5 days, and 10 days. There were two methods of mixing: first, peat was mixed with fly ash geopolymer activators and mixed solution (waterglass, NaOH, water), and second, peat was mixed with fly ash and mixed geopolymer (waterglass, NaOH, water, fly ash). Changes were observed in specific gravity, dry density, acidity (pH), and the microscopic structure with Scanning Electron Microscope (SEM). Curing time did not significantly affect the CBR value. It even shows a tendency to decline with longer curing time. The first type mixture obtained CBR value of: 5.4% for 4 hours curing, 4.6% for 5 days curing and 3.6% for 10 days curing. The second type mixture obtained CBR value of: 6.1% for 4 hours curing, 5.2% for 5 days curing and 5.2% for 10 days curing. Furthermore, the specific gravity value, dry density, pH near neutral and swelling percentage increased. From both variants, the second type mixture shows better results than the first type mixture. The results of SEM (Scanning Electron Microscopy) show the structure of the peat which became denser with the fly ash particles filling the peat microporous. Also, the reaction of fly ash with geopolymer is indicated by the solid agglomerates that are larger than normal fly ash particle size.

Specific features of the development of soils of hydromorphic ecosystems in the northern taiga of Western Siberia under conditions of cryogenesis

NASA Astrophysics Data System (ADS)

Matyshak, G. V.; Bogatyrev, L. G.; Goncharova, O. Yu.; Bobrik, A. A.

2017-10-01

Differently directed and heterochronous cryogenic processes have contributed to the contrasting soil cover patterns and spatial heterogeneity of the properties of soils in hydromorphic ecosystems of the discontinuous permafrost zone of the northern taiga in Western Siberia. Frost heave and permafrost thawing within ecosystems of highmoor bogs have led to the development of specific cryogenic landforms, such as flat-topped and large peat mounds. A set of cryogenic soils is developed in these ecosystems; it includes different variants of cryozems, gleyzems (Cryosols), and peat soils (Histosols). The distribution of these soil types is controlled by the local topography and thawing depth, other factors being insignificant. Alternation of peat horizons of different types and ages, whirl-like patterns of horizon boundaries, considerable variations in the thickness of soil horizons, and inversions of soil horizons under the impact of frost cracking, frost heave, and cryoturbation are typical of the considered soils. Thawing depth is the most significant factor affecting the thickness of organic horizons, the soil pH, and the degree of decomposition of peat. As a result of the upward movement of bog ecosystems under the impact of frost heave, peat soils are subjected to considerable transformation: peat horizons undergo mineralization, and the thickness of organic horizons decreases; in some cases, eluvial-illuvial differentiation of the mineral horizons takes place, and peat podzols are developed. However, the opposite process of the return of the soils to the bog stage of pedogenesis with peat accumulation may take place in any time in the case of activation of thermokarst processes.

The Use of Hotspot Spatial Clustering and Multitemporal Satellite Imagery to Facilitate Peat Land Degradation in West Kalimantan, Indonesia (Case Study in Mensiku Miniwatershed of Kapuas River)

NASA Astrophysics Data System (ADS)

Yanuarsyah, I.; Suwarno, Y.; Hudjimartsu, S.

2016-11-01

Peat land in Indonesia is currently a matter of interest to economic activity. In addition to having the uniqueness of the ecosystem which is reserve a huge of biodiversity and carbon storage, peat land is grow an alternative expansion of agriculture and plantation. Mensiku miniwatershed is a subset of Kapuas Watershed with the domination of the peat soil type. It located in the upstream from the Kapuas River and supporting for the continuation of the river ecosystem. The research objective is to facilitate peat land degradation by using hotspot spatial clustering and multitemporal satellite imagery. There have three main processes which are image processing, geoprocessing and statistical process using DBSCAN to determine hotspot clustering. The trend of LUC changes for 14 years (2002 to 2016) shows that the downward occurred in secondary peat forest (0.9% per year) and swampy shrub (0.6% per year). The upward occurred in mixed farms (0.6% per year) and plantations (0.8% per year). degradation rate of peat land over 14 years about 4.6 km2 per year. Hotspot predominantly occurrence in secondary peat forest with 200-250 centimeter depth and Saprists type. DBSCAN clustering obtain 2 clusters in 2002, obtain 4 clusters in 2009 and obtain 1 clusters in 2016. Regarding LUC platform, average density value over 14 years about 0.063 hotspot per km2. DBSCAN is common used to examine the cluster and perform the distribution and density with spatial analysis

Impact of the water salinity on the hydraulic conductivity of fen peat

NASA Astrophysics Data System (ADS)

Gosch, Lennart; Janssen, Manon; Lennartz, Bernd

2017-04-01

Coastal peatlands represent an interface between marine and terrestrial ecosystems; their hydrology is affected by salt and fresh water inflow alike. Previous studies on bog peat have shown that pore water salinity can have an impact on the saturated hydraulic conductivity (Ks) of peat because of chemical pore dilation effects. In this ongoing study, we are aiming at quantifying the impact of higher salinities (up to 3.5 %) on Ks of fen peat to get a better understanding of the water and solute exchange between coastal peatlands and the adjacent sea. Two approaches differing in measurement duration employing a constant-head upward-flow permeameter were conducted. At first, Ks was measured at an initial salinity for several hours before the salinity was abruptly increased and the measurement continued. In the second approach, Ks was measured for 15 min at the salt content observed during sampling. Then, samples were completely (de)salinized via diffusion for several days/weeks before a comparison measurement was carried out. The results for degraded fen peats show a decrease of Ks during long-term measurements which does not depend on the water salinity. A slow, diffusion-controlled change in salinity does not modify the overall outcome that the duration of measurements has a stronger impact on Ks than the salinity. Further experiments will show if fen peat soils differing in their state of degradation exhibit a different behavior. A preliminary conclusion is that salinity might have a less important effect on hydraulic properties of fen peat than it was observed for bog peat.

Evaluation of the Nutraceutical and Cosmeceutical Potential of Two Cultivars of Rubus fruticosus L. under Different Cultivation Conditions.

PubMed

Papaioanou, Maria; Chronopoulou, Evangelia G; Ciobotari, Gheorghii; Efrose, Rodica C; Sfichi-Duke, Liliana; Chatzikonstantinou, Marianna; Pappa, Evangelia; Ganopoulos, Ioannis; Madesis, Panagiotis; Nianiou-Obeidat, Irini; Zeng, Taofen; Labrou, Nikolaos E

2017-01-01

The starting point for the development of new, functional products derived from Rubus fruticosus L. is to determine the optimal cultivation conditions that produce maximal yield of fruits containing desirable bioactive properties. Towards that goal, the effect of soil, soil/peat mixture and light intensity on the nutraceutical and cosmeceutical potential of two cultivars ('Thornfree' and 'Loch Ness') of Rubus fruticosus L. were evaluated. The assessment was carried out employing a range of methods for evaluating fruit properties associated with promoting good health such as total antioxidant capacity, secondary metabolites content (vitamin C, polyphenols, flavonoids and anthocyanins) and inhibition analysis of skin-regulating enzymes. 'Thornfree' cultivar produced fruits in all light conditions, while 'Loch Ness' did not produce fruits in low light conditions. The results showed that in Rubus fruticosus L. fruit, the chemical composition and bioactivity are strongly affected by both genetics factors and growing conditions. Extract from 'Thornfree' fruits obtained under low light and soil/peat conditions displayed superior properties such as high antioxidant capacity, high concentrations of phenolics, flavonoids and anthocyanins and high inhibitory potency towards the enzymes tyrosinase and elastase. This extract was used for the development of a topical skin care cream with excellent compatibility and stability. Our findings conclude that Rubus fruticosus L. cultivation may be efficiently and effectively manipulated through conventional cultivation techniques to produce promising bioactive ingredients with potential use in commercial cosmetics and pharmaceuticals. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Phenols as chemical fossils in coals. [Book chapter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bimer, J.; Given, P.H.; Raj, S.

It is generally considered that vitrinite, the principal maceral in most coals, represents coalified, partly decayed wood. Hence lignin should be one of the important precursors to the vitrinites in coals. Accordingly, it would be interesting to know whether any chemical fossils related to lignin could be found in coals. The purpose of this paper is to report what we believe to be a successful search for such fossils. The experimental approach exploited a degradation reaction developed in a study of soil humic acids by Burges et al. This reaction involves a reductive degradation with sodium amalgam and hot water.more » Thin layer chromatography of the ether soluble part of the product (yield, about 20%) showed the presence of a number of phenols and phenolic acids, most of whose structures bore obvious relationships to known microbial and chemical degradation products of lignin but some to the A ring of flavonoids. Humic acids can be extracted from peats and lignites but not from bituminous coals. However, oxidation of bituminous coals with aqueous performic acid generates in high yield (80 to 110% by weight) materials that closely resemble humic acids. The Burges reductive degradation was applied to humic acids extracted from some peats and lignites, and produced by oxidation of a number of bituminous coals. A number of identifications of products were made originally by gas chromatography with co-injection of standards. In this preliminary publication the experimental procedures are described and a sufficient selection of the data are given to show what was found by co-injection and later confirmed by mass spectrometry.« less

Climate mitigation scenarios of drained peat soils

NASA Astrophysics Data System (ADS)

Kasimir Klemedtsson, Åsa; Coria, Jessica; He, Hongxing; Liu, Xiangping; Nordén, Anna

2014-05-01

The national inventory reports (NIR) submitted to the UNFCCC show Sweden - which as many other countries has wetlands where parts have been drained for agriculture and forestry purposes, - to annually emit 12 million tonnes carbon dioxide equivalents, which is more GHG'es than industrial energy use release in Sweden. Similar conditions can be found in other northern countries, having cool and wet conditions, naturally promoting peat accumulation, and where land use management over the last centuries have promoted draining activities. These drained peatland, though covering only 2% of the land area, have emissions corresponding to 20% of the total reported NIR emissions. This substantial emission contribution, however, is hidden within the Land Use Land Use Change and Forestry sector (LULUCF) where the forest Carbon uptake is even larger, which causes the peat soil emissions become invisible. The only drained soil emission accounted in the Swedish Kyoto reporting is the N2O emission from agricultural drained organic soils of the size 0.5 million tonnes CO2e yr-1. This lack of visibility has made incentives for land use change and management neither implemented nor suggested, however with large potential. Rewetting has the potential to decrease soil mineralization, why CO2 and N2O emissions are mitigated. However if the soil becomes very wet CH4 emission will increase together with hampered plant growth. By ecological modeling, using the CoupModel the climate change mitigation potential have been estimated for four different land use scenarios; 1, Drained peat soil with Spruce (business as usual scenario), 2, raised ground water level to 20 cm depth and Willow plantation, 3, raised ground water level to 10 cm depth and Reed Canary Grass, and 4, rewetting to an average water level in the soil surface with recolonizing wetland plants and mosses. We calculate the volume of biomass production per year, peat decomposition, N2O emission together with nitrate and DOC/POC leakage. Based on the modelling results a cost benefit analysis is performed (economics), guiding to the design of environmental policies needed for land use change to come true.

Impacts of road construction and removal on the hydrologic and geochemical function of a fen peatland

NASA Astrophysics Data System (ADS)

Wells, C. M.; Petrone, R. M.; Sutherland, G.; Price, J. S.

2015-12-01

Linear disturbances such as roads cover vast swaths of northeastern Alberta, the majority of which are wetlands with shallow and local hydrologic connections. Thus, the effects of road construction on wetland hydrological pathways can have significant implications on water movement within the region, and by extension the productivity of vegetation communities and carbon sequestration. However, little is known about the effect that roads have on wetland hydrology. In 2013, a gravel road built within a fen peatland was reclaimed to evaluate hydrologic impacts post removal. Prior to removal, ground and surface water flow was obstructed leading to surface ponding, and vegetation mortality was observed on the up-gradient (wet) side of the road. Rebounding of the peat column was observed throughout the fen immediately following road removal in 2013 (maximum of 12 cm, mean of 2 cm), with modest but slightly smaller expansion in 2014. For both years, peat rebound was greatest in areas where the road was removed. Peat physical properties contrasted sharply between the reclaimed road (RR) peat and the adjacent, unimpacted peatland (UP). Surface bulk densities (pb, 0-10 cm) ranged from 0.1-0.25 g cm-3 along the RR compared to 0.02-0.07 g cm-3 for the UP and on average, pb for all depths were lower at the RR compared to the UP. Similar spatial patterns were observed for peat porosity. Correspondingly low horizontal saturated hydraulic conductivities (Kh) were observed along the RR compared to the UP, averaging 5.7x10-4 m s-1 and 1.7x10-3 m s-1, respectively. The local flow system across the RR and thus subsurface flow was impeded by almost half (0.4 m d-1) compared to flow observed within the UP (0.8 m d-1), leading to ponding on the upgradient side. A marked change in hydrophysical properties and ground and surface water flow patterns post road removal has implications for plant reestablishment and restoration and will form the basis of further study.

Modelling mercury accumulation in minerogenic peat combining FTIR-ATR spectroscopy and partial least squares (PLS)

NASA Astrophysics Data System (ADS)

Pérez-Rodríguez, Marta; Horák-Terra, Ingrid; Rodríguez-Lado, Luis; Martínez Cortizas, Antonio

2016-11-01

Despite its potential, infrared spectroscopy combined with multivariate statistics has been seldom used to model peat properties with environmental value, such us the concentration of potentially toxic metals. In this research, we applied attenuated total reflectance (ATR) Fourier-Transform Infrared (FTIR) spectroscopy to evaluate the ability of the technique to predict mercury concentrations in late-Pleistocene/Holocene peat from a minerogenic peatland from Minas Gerais (Brazil). Mercury concentrations were analysed using a Milestone DMA-80 analyzer and attenuated total reflectance FTIR-ATR was performed using a Gladi-ATR (Pike Technologies) in the mid IR spectrum (4000-400 cm- 1). Concentrations were modelled using principal components (PCR) and partial least squares regression (PLS). The performance of the models varied between moderate and very good (R2 0.67-0.90), with low RMSD values (0.35-1.06). A PLS model based on three latent vectors (LV1 to LV3) provided the best (R2 0.90, RMSD 0.35) results. LV1 reflected total organic matter content versus mineral matter (mainly quartz from local fluxes), LV2 was related to dust deposition from regional sources, and LV3 reflected peat organic matter decomposition. Compared to a previous investigation based on geochemical data, the spectroscopy-based PLS model performed better, but it has to be complemented with additional data (as δ13 C ratios) to reliably reproduce the changes of the factors controlling mercury accumulation over time. This, time- and cost-effective, methodology may help to develop multi-core approaches to study the within and between mire (of a similar type and area) variability in mercury accumulation, and probably also other peat properties. Fig. S2 Loadings weights of the three and two significant components from the direct (dPCR) and transposed (trPCR) PCR models. Fig. S3 Depth records of the cumulative effects of the factors involved in the variation of mercury concentrations. Left, MIR-PLS model; centre, MIR-PLS + δ13 C data model; right, geochemical model from Pérez-Rodríguez et al. [44].

Comparative Efficiency of the Fenwick Can and Schuiling Centrifuge in Extracting Nematode Cysts from Different Soil Types

PubMed Central

Bellvert, Joaquim; Crombie, Kieran; Horgan, Finbarr G.

2008-01-01

The Fenwick can and Schuiling centrifuge are widely used to extract nematode cysts from soil samples. The comparative efficiencies of these two methods during cyst extraction have not been determined for different soil types under different cyst densities. Such information is vital for statutory laboratories that must choose a method for routine, high-throughput soil monitoring. In this study, samples of different soil types seeded with varying densities of potato cyst nematode (Globodera rostochiensis) cysts were processed using both methods. In one experiment, with 200 ml samples, recovery was similar between methods. In a second experiment with 500 ml samples, cyst recovery was higher using the Schuiling centrifuge. For each method and soil type, cyst extraction efficiency was similar across all densities tested. Extraction was efficient from pure sand (Fenwick 72%, Schuiling 84%) and naturally sandy soils (Fenwick 62%, Schuiling 73%), but was significantly less efficient from clay-soil (Fenwick 42%, Schuiling 44%) and peat-soil with high organic matter content (Fenwick 35%, Schuiling 33%). Residual moisture (<10% w/w) in samples prior to analyses reduced extraction efficiency, particularly for sand and sandy soils. For each soil type and method, there were significant linear relationships between the number of cysts extracted and the numbers of cysts in the samples. We discuss the advantages and disadvantages of each extraction method for cyst extraction in statutory soil laboratories. PMID:19259516

Sources and yields of dissolved carbon in northern Wisconsin stream catchments with differing amounts of Peatland

USGS Publications Warehouse

Elder, J.F.; Rybicki, N.B.; Carter, V.; Weintraub, V.

2000-01-01

In five tributary streams (four inflowing and one outflowing) of 1600-ha Trout Lake in northern Wisconsin, USA, we examined factors that can affect the magnitude of stream flow and transport of dissolved organic and inorganic carbon (DOC and DIC) through the streams to the lake. One catchment, the Allequash Creek basin, was investigated in more detail to describe the dynamics of carbon flow and to identify potential carbon sources. Stream flows and carbon loads showed little or no relation to surface-water catchment area. They were more closely related to ground-water watershed area because ground-water discharge, from both local and regional sources, is a major contributor to the hydrologic budgets of these catchments. An important factor in determining carbon influx to the stream is the area of peatland in the catchment. Peatland porewaters contain DOC concentrations up to 40 mg l-1 and are a significant potential carbon source. Ground-water discharge and lateral flow through peat are the suspected mechanisms for transport of that carbon to the streams. Carbon and nitrogen isotopes suggested that the sources of DOC in Allequash Creek above Allequash Lake were wetland vegetation and peat and that the sources below Allequash Lake were filamentous algae and wild rice. Catchments with high proportions of peatland, including the Allequash Creek catchment, tended to have elevated DOC loads in outflowing stream water. Respiration and carbon mineralization in lakes within the system tend to produce low DOC and low DOC/DIC in lake outflows, especially at Trout Lake. In Allequash Lake, however, the shallow peat island and vegetation-filled west end were sources of DOC. Despite the vast carbon reservoir in the peatlands, carbon yields were very low in these catchments. Maximum yields were on the order of 2.5 g m-2 y-1 DOC and 5.5 g m-2 y-1 DIC. The small yields were attributable to low stream flows due to lack of significant overland runoff and very limited stream channel coverage of the total catchment area.

Developing of a network of nature reserves in the Lublin Region

NASA Astrophysics Data System (ADS)

Stanicka, Małgorzata

2010-01-01

The nature reserves are one of the oldest forms of nature conservation. Legal basis for their establishment in Poland gave the Nature Conservation Act of 1934, but much earlier, it originated on private land or in state forests. The natural environment of the Lublin Region was poorly understood. Only after the emergence of Maria Curie-Skłodowska University in Lublin in 1944, there started intensive research, mainly in Roztocze and Polesie Lubelskie. The development of the natural science enhanced learning activities for the protection of natural objects. The author presents the history of the creation of nature reserves in the Lublin Region from 1933 to 2008. The first reserves - Jata and Topór were approved in 1933 in the Łuków Forests. In 1934 the famous reserve Bukowa Góra in Roztocze, in Zamoyski Ordination, was approved. In the period 1933-2008, 103 nature reserves were established in the Lublin Region, of which 11 were included in the Roztoczański and 5 in the Poleski National Park. The area of 87 existing nature reserves in the Lublin Region is 6.8% of the reserves in Poland. The reserves represent 8 from 9 types distinguished in Poland - 35 forest reserves, 16 peat, 12 faunal, 8 steppe, 6 landscape, 6 floral, 3 inanimate nature, and 1 water reserve. Against the background of Poland, the Lublin province takes the first place (!) in terms of reserves in the steppe area (30.3% of steppe reserves in the country) and peat (19% of the peat reserves in the country), and the third in terms of the area of forest reserves (9.7% of forest reserves in the country). A large area of forest reserves in the region of low forest cover (22.5% and 14th place in the country) shows the value of natural forests and note that is attached to their protection in the Lublin Region. The annex contains a list of 103 reserves established in the Lublin Region after World War II.

Cardiopulmonary toxicity of peat wildfire particulate matter and the predictive utility of precision cut lung slices

EPA Science Inventory

Background: Emissions from a large peat fire in North Carolina were associated with increased hospital admissions for asthma and the rate of heart failure in the exposed population. Peat fires often produce larger amounts of smoke and last longer than forest fires, however few st...

Food waste composting: its use as a peat replacement.

PubMed

Farrell, M; Jones, D L

2010-01-01

We successfully co-composted catering waste with green waste and shredded paper to yield two high-nitrogen composts for use in horticulture. Sunflowers (Helianthus annuus L.) were grown in various mixtures of the compost and a commercially available peat-based compost to assess the efficacy of catering waste-based composts for peat replacement. Height, head diameter, seed mass and above-ground biomass were measured, with all mixtures giving a significant increase in yield or size over the commercially available peat-free control compost. We conclude that differences in physical structure governed sunflower growth over substrate chemistry, and none of the compost mixtures were nutrient deficient. We recommend that catering waste co-compost can be substituted to at least 75% within Sphagnum-based traditional growing media, providing a viable replacement for a large proportion of peat used as a growth medium in the horticulture industry. Our catering waste compost yielded similar seed head, seed mass and above-ground biomass values to 100% peat-based compost in all food waste compost blends tested in this study. 2010 Elsevier Ltd. All rights reserved.

High nitrogen availability reduces polyphenol content in Sphagnum peat.

PubMed

Bragazza, Luca; Freeman, Chris

2007-05-15

Peat mosses of the genus Sphagnum constitute the bulk of living and dead biomass in bogs. These plants contain peculiar polyphenols which hamper litter peat decomposition through their inhibitory activity on microbial breakdown. In the light of the increasing availability of biologically active nitrogen in natural ecosystems, litter derived from Sphagnum mosses is an ideal substrate to test the potential effects of increased atmospheric nitrogen deposition on polyphenol content in litter peat. To this aim, we measured total nitrogen and soluble polyphenol concentration in Sphagnum litter peat collected in 11 European bogs under a chronic gradient of atmospheric nitrogen deposition. Our results demonstrate that increasing nitrogen concentration in Sphagnum litter, as a consequence of increased exogenous nitrogen availability, is accompanied by a decreasing concentration of polyphenols. This inverse relationship is consistent with reports that in Sphagnum mosses, polyphenol and protein biosynthesis compete for the same precursor. Our observation of modified Sphagnum litter chemistry under chronic nitrogen eutrophication has implications in the context of the global carbon balance, because a lower content of decay-inhibiting polyphenols would accelerate litter peat decomposition.

The rare peat moss Sphagnum wulfianum (Sphagnaceae) did not survive the last glacial period in northern European refugia.

PubMed

Kyrkjeeide, Magni Olsen; Hassel, Kristian; Flatberg, Kjell I; Stenøien, Hans K

2012-04-01

Organisms may survive unfavorable conditions either by moving to more favorable areas by means of dispersal or by adapting to stressful environments. Pleistocene glacial periods represent extremely unfavorable conditions for the majority of life forms, especially sessile organisms. Many studies have revealed placements of refugial areas and postglacial colonization patterns of seed plants, but little is still known about areas of long-term survival and historical migration routes of bryophytes. Given overall differences in stress tolerance between seed plants and bryophytes, it is of interest to know whether bryophytes have survived periods of extreme climatic conditions better then seed plants in northern areas. The haploid and rarely spore-producing peat moss Sphagnum wulfianum is mostly found in areas that were covered by ice during the last glacial maximum. Twelve microsatellite markers were amplified from 43 populations (367 shoots) of this species, and data were analyzed using population genetic diversity statistics, Bayesian clustering methods, and coalescence-based inference tools to estimate historical and demographic parameters. Genetic diversity within populations was low, but populations were highly differentiated, with two main genetic clusters being recognized. The two main genetic groups have diverged quite recently in the Holocene, and the pattern of genetic variability and structuring gives no support for survival in Scandinavian refugia during the last glacial period in this species. The dispersal ability of this plant thus seems surprisingly high despite its infrequent spore production.

Solute movement in drained fen peat: a field tracer study in a Somerset (UK) wetland

NASA Astrophysics Data System (ADS)

Baird, Andrew J.; Gaffney, Simon W.

2000-10-01

Little is known about solute transport in peats, despite the obvious importance of solute transport on eco-hydrological processes in both managed and natural peatlands. To address this lack of knowledge, we investigated solute transport processes in an agricultural fen peat using a conservative KBr tracer. The main aim of the study was to elucidate solute transport behaviour in general in this peat, with a more specific aim of investigating whether preferential or bypassing flow occurred. The tracer moved through the peat more rapidly than expected, and the pattern of movement showed clear evidence of plot-scale bypassing flow. The data also provide evidence that bypassing flow occurs in pores at smaller scales. The implications of this study for management of wetland pastures in the Somerset Moors in south-west England are discussed.

The sensitivity of peat soil and peatland vegetation to drought: release of dissolved organic carbon (DOC) on rewetting

NASA Astrophysics Data System (ADS)

Ritson, Jonathan; Graham, Nigel; Templeton, Michael; Freeman, Christopher; Clark, Joanna

2015-04-01

Organic rich peat soils are a major store of carbon worldwide. Their existence is predicated on high year-round water tables which create an anoxic environment, thus limiting decay, and also to the recalcitrance of plant litter (dead plant material) commonly found in peatland areas. Climate change threatens the stability of peat soils by altering the biogeochemical cycles which control plant decay, lowering water tables so that oxic degradation can occur and by changing habitat niches such that less recalcitrant species can thrive in peatlands. One of the major fluxes of carbon from peatlands is through dissolved organic carbon (DOC) in surface waters. As peatland areas in the UK are often used as source waters for drinking water supply this presents a problem to water utilities as DOC must be effectively removed to limit colour, odour and the formation of potentially carcinogenic by-products on disinfection. Changes in catchment vegetation may occur due to climate change, nutrient deposition and changing bioclimatic envelopes. How different peatland vegetation contribute to DOC flux and how this may change in the future is therefore of interest. A six week laboratory simulation was performed on typical peatland litter (Sphagnum spp., Calluna vulgaris, Molinea caerulea, Juncus effusus) and a peat soil collected from Exmoor National Park, UK. The simulation monitored DOC flux from the decaying litter/soil and considered the impact of different drought severities using the 50th, 25th, 10th and 5th percentiles of the mean July/August monthly rainfall for Exmoor. On rewetting following the drought, all sources produced significantly different amounts of DOC (Tukey HSD p<0.05) in the order Molinia>Juncus>Calluna>Sphagnum>peat. The source also had a significant (ANOVA p<0.001) effect on coagulation removal efficiency, a typical method of removing DOC during drinking water treatment, with Juncus DOC proving the easiest to remove whilst Sphagnum DOC was the most difficult. Sphagnum DOC had the lowest ratio of humic-like to protein-like fluorescence, which is indicative of DOC which is poorly removed by coagulation. An interactive effect was noted between DOC source and the drought treatment which was explored further using a one-way ANOVA with a Holm-Šidák correction. This suggested peat will produce significantly more DOC when affected by drought (p=0.010), possibly explained by increased oxygenation engaging the 'enzymatic latch' mechanism. A similar analysis was performed on the interaction between drought and DOC source for the specific UV absorbance at 254nm (SUVA) value (a measure of aromaticity). This suggested that Molinea caerulea produces DOC of significantly (p=0.001) higher aromaticity following periods of drought. Comparisons between drought and DOC source factors suggest the source in more important than climatic conditions of decay which is consistent with our previously published findings. These results have implications for marginal peatlands which may be at risk from increased water table drawdown in the future as climate changes and where Molinea caerulea, typically a fen species, is encroaching on bog communities.

Thickness and quality of Springfield Coal Member, Gibson County, Indiana, as a function of differential compaction of precursor sediments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eggert, D.L.

1983-09-01

The Springfield Coal Member is a time transgressive coal that formed during the Pennsylvanian on a delta platform within the slowly subsiding Illinois basin. In Gibson County, Indiana, the locations of the major Galatia channel and the minor Leslie Cemetery channel were determined by differential compaction of precursor sediments beneath this platform. The springfield coal is thick proximal to both channels, but proximal to the Galatia channel it is either a low-sulfur or a high-sulfur coal. It is a low-sulfur coal where it is underlain by a thick platform of shale with some sandstone and overlain by nonmarine shale. Itmore » is a high-sulfur coal where it is underlain by a thick platform of fluvial sandstone and overlain by brackish to marine rocks. Distal to both channels the coal is thin and high in sulfur. At distal locations the Springfield is underlain by a platform of either thick bay-fill sandstone or fluvial sandstone and overlain by brackish to marine shale and limestone. Compaction of pre-Springfield delta sediments allowed for accumulation of thicker peat along the axis of more rapid local subsidence. Compaction of muddy parts of the delta platform proximal to the Galatia channel resulted in rapid subsidence and the deposition of nonmarine shale over the peat. In the areas underlain by bay-fill and fluvial sandstone where compaction was less, the peat became a relatively thin and high-sulfur coal. Differences in coal thickness and quality in this 500 mi/sup 2/ (1,300 km/sup 2/) area of Gibson County can be explained largely by differential compaction and deltaic sedimentation.« less

Carbon dioxide emissions from forestry and peat land using land-use/land-cover changes in North Sumatra, Indonesia

NASA Astrophysics Data System (ADS)

Basyuni, M.; Sulistyono, N.; Slamet, B.; Wati, R.

2018-03-01

Forestry and peat land including land-based is one of the critical sectors in the inventory of CO2 emissions and mitigation efforts of climate change. The present study analyzed the land-use and land-cover changes between 2006 and 2012 in North Sumatra, Indonesia with emphasis to CO2 emissions. The land-use/land-cover consists of twenty-one classes. Redd Abacus software version 1.1.7 was used to measure carbon emission source as well as the predicted 2carbon dioxide emissions from 2006-2024. Results showed that historical emission (2006-2012) in this province, significant increases in the intensive land use namely dry land agriculture (109.65%), paddy field (16.23%) and estate plantation (15.11%). On the other hand, land-cover for forest decreased significantly: secondary dry land forest (7.60%), secondary mangrove forest (9.03%), secondary swamp forest (33.98%), and the largest one in the mixed dry land agriculture (79.96%). The results indicated that North Sumatra province is still a CO2 emitter, and the most important driver of emissions mostly derived from agricultural lands that contributed 2carbon dioxide emissions by 48.8%, changing from forest areas into degraded lands (classified as barren land and shrub) shared 30.6% and estate plantation of 22.4%. Mitigation actions to reduce carbon emissions was proposed such as strengthening the forest land, rehabilitation of degraded area, development and plantation forest, forest protection and forest fire control, and reforestation and conservation activity. These mitigation actions have been simulated to reduce 15% for forestry and 18% for peat land, respectively. This data is likely to contribute to the low emission development in North Sumatra.

2000 Years of Grazing History and the Making of the Cretan Mountain Landscape, Greece.

PubMed

Jouffroy-Bapicot, Isabelle; Vannière, Boris; Iglesias, Virginia; Debret, Maxime; Delarras, Jean-François

2016-01-01

Understanding the processes that led to the recent evolution of Mediterranean landscapes is a challenging question that can be addressed with paleoecological data. Located in the White Mountains of Crete, Asi Gonia peat bog constitutes an exceptional 2000-years-long sedimentary archive of environmental change. In this study, we document the making of the White Mountains landscape and assess human impact on ecosystem trajectories. The paleoenvironmental reconstruction is based on high-resolution analyses of sediment, pollen, dung fungal spores and charcoal obtained from a 6-m core collected from the bog. Multiproxy analyses and a robust chronological control have shed light on anthropogenic and natural processes that have driven ecological changes, giving rise to the present-day Mediterranean ecosystem. Our results suggest that sediment accumulation began during the transition from the Hellenistic to the Roman period, likely due to watershed management. The evolution of the peat bog as well as vegetation dynamics in the surrounding area were linked to past climate changes but were driven by human activities, among which breeding was of great importance. Charcoal analysis reveals that fire was largely used for the construction and maintenance of sylvo-agropastoral areas. Pollen data allow the identification of three main vegetation assemblages: 1) evergreen oak forest (before ca. 850 AD), 2) heather maquis (ca. 850 to 1870 AD), 3) phrygana/steppe landscape. Rapid changes between phases in vegetation development are associated with tipping-points in ecosystem dynamics resulting from anthropogenic impact. The modern ecosystem did not get established until the 20th century, and it is characterized by biodiversity loss along with a dramatic drying of the peat bog.

2000 Years of Grazing History and the Making of the Cretan Mountain Landscape, Greece

PubMed Central

Jouffroy-Bapicot, Isabelle; Vannière, Boris; Iglesias, Virginia; Debret, Maxime; Delarras, Jean-François

2016-01-01

Understanding the processes that led to the recent evolution of Mediterranean landscapes is a challenging question that can be addressed with paleoecological data. Located in the White Mountains of Crete, Asi Gonia peat bog constitutes an exceptional 2000-years-long sedimentary archive of environmental change. In this study, we document the making of the White Mountains landscape and assess human impact on ecosystem trajectories. The paleoenvironmental reconstruction is based on high-resolution analyses of sediment, pollen, dung fungal spores and charcoal obtained from a 6-m core collected from the bog. Multiproxy analyses and a robust chronological control have shed light on anthropogenic and natural processes that have driven ecological changes, giving rise to the present-day Mediterranean ecosystem. Our results suggest that sediment accumulation began during the transition from the Hellenistic to the Roman period, likely due to watershed management. The evolution of the peat bog as well as vegetation dynamics in the surrounding area were linked to past climate changes but were driven by human activities, among which breeding was of great importance. Charcoal analysis reveals that fire was largely used for the construction and maintenance of sylvo-agropastoral areas. Pollen data allow the identification of three main vegetation assemblages: 1) evergreen oak forest (before ca. 850 AD), 2) heather maquis (ca. 850 to 1870 AD), 3) phrygana/steppe landscape. Rapid changes between phases in vegetation development are associated with tipping-points in ecosystem dynamics resulting from anthropogenic impact. The modern ecosystem did not get established until the 20th century, and it is characterized by biodiversity loss along with a dramatic drying of the peat bog. PMID:27280287

Ecosystem and physiological controls over methane production in northern wetlands

NASA Technical Reports Server (NTRS)

Valentine, David W.; Holland, Elisabeth A.; Schimel, David S.

1994-01-01

Peat chemistry appears to exert primary control over methane production rates in the Canadian Northern Wetlands Study (NOWES) area. We determined laboratory methane production rate potentials in anaerobic slurries of samples collected from a transect of sites through the NOWES study area. We related methane production rates to indicators of resistance to microbial decay (peat C: N and lignin: N ratios) and experimentally manipulated substrate availability for methanogenesis using ethanol (EtOH) and plant litter. We also determined responses of methane production to pH and temperature. Methane production potentials declined along the gradient of sites from high rates in the coastal fens to low rates in the interior bogs and were generally highest in surface layers. Strong relationships between CH4 production potentials and peat chemistry suggested that methanogenesis was limited by fermentation rates. Methane production at ambient pH responded strongly to substrate additions in the circumneutral fens with narrow lignin: N and C: N ratios (delta CH4/delta EtOH = 0.9-2.3 mg/g) and weakly in the acidic bogs with wide C: N and lignin: N ratios (delta CH4/delta EtOH = -0.04-0.02 mg/g). Observed Q(sub 10) values ranged from 1.7 to 4.7 and generally increased with increasing substrate availability, suggesting that fermentation rates were limiting. Titration experiments generally demonstrated inhibition of methanogenesis by low pH. Our results suggest that the low rates of methane emission observed in interior bogs during NOWES likely resulted from pH and substrate quality limitation of the fermentation step in methane production and thus reflect intrinsically low methane production potentials. Low methane emission rates observed during NOWES will likely be observed in other northern wetland regions with similar vegetation chemistry.

Effect of Organic Material on Mechanical, Hydrological, and Microstructural Properties of Mudstones

NASA Astrophysics Data System (ADS)

Altobelli, M. A.; Reece, J. S.

2016-12-01

In this research we analyze the influence of organic material on the mechanical and flow properties of mudstones. We uniformly mix peat, milled and harvested by Bord na Móna from the surface of bogs in Ireland, with natural mudstone from Site C0011 in the Nankai Trough, offshore Japan, obtained during Integrated Ocean Drilling Program Expedition 322. The mudstone had previously been disaggregated into a homogeneous dry powder of clay- and silt-sized particles. The peat is ground and dry-sieved to achieve a similar particle size distribution as the mudstone (< 63 micrometers). In order to understand the mechanical and hydrological processes affected by peat, we prepare dry peat-mudstone mixtures with three different peat concentrations: 0 wt%, 5 wt%, and 10 wt%. Then, these peat - mudstone mixtures are saturated with deionized water at a water content of 109%, formed into stable slurries, and uniaxially compressed to an axial stress of 100 kPa using resedimentation, a method that simulates the natural behavior of deposition and burial in the laboratory under controlled conditions. How the organic material interacts with the mudstone matrix and pore fluid under compression influences the physical properties of the mudstones such as porosity, compressibility, and permeability; all of which are measured in the resedimentation experiments. We will also analyze the microstructural changes as a function of peat concentration using a petrographic microscope and scanning electron microscope. Due to the fibrous and absorbent nature of peat, we anticipate the peat to force tightly packed clay particles in the mudstone apart resulting in a looser microstructure and increased porosity, and thus, a higher compressibility and permeability. Understanding the controls on the mechanical and flow properties of hydrocarbon-bearing, fine-grained formations is crucial for exploration and successful production from hydrocarbon reservoirs. Additionally, this study has large implications for soil water storage and soil amendment to improve plant growth and health in clayey soils.

Coal and peat in the sub-Saharan region of Africa: alternative energy options?

USGS Publications Warehouse

Weaver, J.N.; Landis, E.R.

1990-01-01

Coal and peat are essentially unused and in some cases unknown in sub-Saharan Africa. However, they might comprise valuable alternative energy sources in some or all of the developing nations of the region. The 11 countries considered in this appraisal reportedly contain coal and peat. On the basis of regional geology, another five countries might also contain coal-bearing rocks. If the resource potential is adequate, coal and peat might be utilized in a variety of ways including substituting for fuelwood, generating electricity, supplying process heat for local industry and increasing agricultural productivity. -from Author

Geochemical characteristics of peat from two raised bogs of Germany

NASA Astrophysics Data System (ADS)

Mezhibor, A. M.

2016-11-01

Peat has a wide range of applications in different spheres of human activity, and this is a reason for a comprehensive study. This research represents the results of an ICP-MS study of moss and peat samples from two raised bogs of Germany. Because of the wide use of sphagnum moss and peat, determining their geochemical characteristics is an important issue. According to the results obtained, we can resume that the moss samples from Germany are rich in Cu, As, Y, Zr, Nb, and REE. The geochemical composition of the bogs reflects the regional environmental features and anthropogenic influence.

Differing source water inputs, moderated by evaporative enrichment, determine the contrasting δ18OCELLULOSE signals in maritime Antarctic moss peat banks

NASA Astrophysics Data System (ADS)

Royles, Jessica; Sime, Louise C.; Hodgson, Dominic A.; Convey, Peter; Griffiths, Howard

2013-03-01

Oxygen isotope palaeoclimate records, preserved in moss tissue cellulose, are complicated by environmental influences on the relationships between source water inputs and evaporative conditions. We carried out stable isotope analyses of precipitation collected from the maritime Antarctic and cellulose extracted from co-located Chorisodontium aciphyllum dominated moss peat bank deposits accumulated since 1870 A.D. Analyses of stable oxygen and hydrogen isotope composition of summer precipitation on Signy Island (60.7°S, 45.6°W) established a local meteoric water line (LMWL) similar to both the global MWL and other LMWLs, and almost identical to the HadAM3 isotope-enabled global circulation model output. The oxygen isotopic composition of cellulose (δ18OC) revealed little temporal variation between four moss peat banks on Signy Island since 1870. However, δ18OC followed two patterns with Sites A and D consistently 3‰ enriched relative to δ18OC values from Sites B and C. The growing moss surfaces at Sites A and D are likely to have been hydrated by isotopically heavier summer precipitation, whilst at Sites B and C, the moss banks are regularly saturated by the isotopically depleted snow melt streams. Laboratory experiments revealed that evaporative enrichment of C. aciphyllum moss leaf water by 5‰ occurred rapidly following saturation (ecologically equivalent to post-rainfall or snow melt periods). In addition to the recognized source water-cellulose fractionation extent of 27 ± 3‰, such a shift would account for the 32‰ difference measured between δ18O of Signy Island precipitation and cellulose.

Occurrence of organic arsenic species in a 4-m deep free-floating mire

NASA Astrophysics Data System (ADS)

Lobianco, Daniela; Zaccone, Claudio; Raber, Georg; D'Orazio, Valeria; Miano, Teodoro; Francesconi, Kevin

2017-04-01

Wetlands play a key role in the fate of major and trace elements, affecting their environmental mobility and ecotoxicity. Arsenic (As) is a chalcophile element that is recognized as a serious health risk worldwide. Inorganic forms of this metalloid are dominant in soils, whereas the organic forms generally occur only in trace amounts. Nevertheless, methylation processes are responsible for the mobilization of As in several ecosystems, especially in anoxic conditions. Peat cores from ombrotrophic bogs have been used to determine atmospheric depositional fluxes of total As over centuries, although the contribution of organic vs inorganic As species has been rarely considered. Here, 47 peat samples collected throughout a 400-cm deep, free-floating mire have been analysed for total As and for its organic species, including dimethylarsinic acid (DMA), methylarsonic acid (MA), trimethylarsine oxide (TMAO) and arsenobetaine (AB) by HPLC-ICP-MS. Total As concentration throughout the profile ranged between 0.20 and 9.79 mg/kg (1.41±1.36 mg/kg; mean ± st. dev.), showing values that are quite low compared to other mire ecosystems. Organic As species (DMA+MA+TMAO+AB) account, on average, for 28±10% of total As (range 6-47%; median 28%), and for 41±14% of the extracted As (range 7-73%; median 42%). The relative abundance of organoarsenicals generally followed the order DMA>TMAO˜MA>>AB, and was not correlated with main physical and chemical properties of peat, including its degree of decomposition. There was, however, a highly significant (p <0.001) statistical correlation among all organic As compounds. This result provides new insights into the occurrence of organic As species in floating mires, suggesting a possible common biological pathway for their formation.

Using Optical Oxygen Sensors and Injection Experiments to Determine in situ Microbial Rate Constants for Methane Oxidation and Heterotrophic Respiration in a Boreal Bog and Fen

NASA Astrophysics Data System (ADS)

Waldo, N.; Moorberg, C.; Waldrop, M. P.; Turetsky, M. R.; Neumann, R. B.

2015-12-01

Wetlands are the largest natural source of methane to the atmosphere, and play a key role in feedback cycles to climate change. In recognition of this, many researchers are developing process-based models of wetland methane emissions at various scales. In these models, the three key biogeochemical reactions are methane production, methane oxidation, and heterotrophic respiration, and they are modeled using Michaelis-Menten kinetics. The majority of Michaelis-Menten rate constants used in models are based on experiments involving slurries of peat incubated in vials. While these slurries provide a highly controlled setting, they are different from in situ conditions in multiple ways; notably they lack live plants and the centimeter-scale heterogeneities that exist in the field. To determine rate constants in a system more representative of in situ conditions, we extracted peat cores intact from a bog and fen located in the Bonanza Creek Experimental Forest near Fairbanks, Alaska and part of the Alaska Peatland Experiment (APEX) research program. Into those cores we injected water with varying concentrations of methane and oxygen at multiple depths. We used planar oxygen sensors installed on the peat cores to collect high resolution, two dimensional oxygen concentration data during the injections and used oxygen consumption rates under various conditions to calculate rate constants. Results were compared to a similar but smaller set of injection experiments conducted against planar oxygen sensors installed in the bog. Results will inform parametrization of microbial processes in wetland models, improving estimates of methane emissions both under current climate conditions and in the future.

Examination of Below-Ground Structure and Soil Respiration Rates of Stable and Deteriorating Salt Marshes in Jamaica Bay (NY)

EPA Science Inventory

CAT scan imaging is currently being used to examine below-ground peat and root structure in cores collected from salt marshes of Jamaica Bay, part of the Gateway National Recreation Area (NY). CAT scans or Computer-Aided Tomography scans use X-ray equipment to produce multiple i...

Linking Microbial and Biogeochemical Studies: Biological Controls of Methane Release from an Acidic Natural Wetland in Central Pennsylvania

NASA Astrophysics Data System (ADS)

Biddle, J. F.; Turich, C.; Brantley, S.; Bruns, M.

2002-12-01

Wetlands produce between 55 and 150 Tg of methane per year, or ~70% of all natural methane, and 20% of total methane (natural and anthropogenic). Understanding inputs to the global methane cycle depends on integrated in situ study of the sources and sinks of methane, as well as the rate and magnitude of methane production and consumption. Bear Meadows Natural Area in central Pennsylvania (N 40° 43.796' W 077° 45.310; 554 m elevation) contains an acidic, methane-producing, peaty bog with vegetation that is typical of wetlands at higher latitudes. In this four year study conducted within a cross-disciplinary training course offered by the NSF-IGERT Biogeochemical Research Initiative in Education (BRIE) program at Penn State University, graduate students applied a combination of geochemical and microbiological techniques to explore microbial diversity and activity in Bear Meadows sediments. The methane flux at the peat:water interface was highly variable, from 0.01 to over 3000 umol/m2/min in both sphagnum and sedge vegetation. The methane released from the bog had a carbon isotopic composition of -60 %o, typical of biogenic methane. Analysis of peat pore waters showed that the most methane was produced 30 cm below the peat:water interface, with a broad peak of methane in pore waters from 20-40 cm. At 21 cm below the peat:water interface, profiles of Archaeal 16S-23S ribosomal RNA spacer regions revealed the presence of populations having 92% similarity to 16S rRNA sequences of Methanoculleus marisnigri. Phospholipid fatty acids (PLFA) and compound specific isotope analysis revealed other biological controls on the methane cycle. PLFAs typical of methanotrophic bacteria were also present within peat cores from 20-30 cm below the water interface. The depleted carbon isotopic composition of these biomarkers (C16:1 and C18:1 fatty acids) was - 31.4 %o and - 33.8%o, indicative of methane oxidation. The presence of biomarkers of methane oxidizing bacteria within the zone of methane production may indicate that there is temporal or spatial heterogeneity in oxygen concentration within the peat. This interdisciplinary approach helped define specific ecological niches where novel methanogens and methane oxidizers may be active in a typical northern wetland. Through BRIE, on-going studies of the Bear Meadows wetland will focus on detecting other potentially novel aerobic and anaerobic microbes, and determining the biological influence on methane release to the atmosphere.

Volatile and semivolatile organic compounds in laboratory peat fire emissions

NASA Astrophysics Data System (ADS)

George, Ingrid J.; Black, Robert R.; Geron, Chris D.; Aurell, Johanna; Hays, Michael D.; Preston, William T.; Gullett, Brian K.

2016-05-01

In this study, volatile and semi-volatile organic compound (VOCs and SVOCs) mass emission factors were determined from laboratory peat fire experiments. The peat samples originated from two National Wildlife Refuges on the coastal plain of North Carolina, U.S.A. Gas- and particle-phase organic compounds were quantified by gas chromatography-mass spectrometry and by high pressure liquid chromatography. Hazardous air pollutants (HAPs) accounted for a large fraction (∼60%) of the speciated VOC emissions from peat burning, including large contributions of acetaldehyde, formaldehyde, benzene, toluene, and chloromethane. In the fine particle mass (PM2.5), the following organic compound classes were dominant: organic acids, levoglucosan, n-alkanes, and n-alkenes. Emission factors for the organic acids in PM2.5 including n-alkanoic acids, n-alkenoic acids, n-alkanedioic acids, and aromatic acids were reported for the first time for peat burning, representing the largest fraction of organic carbon (OC) mass (11-12%) of all speciated compound classes measured in this work. Levoglucosan contributed to 2-3% of the OC mass, while methoxyphenols represented 0.2-0.3% of the OC mass on a carbon mass basis. Retene was the most abundant particulate phase polycyclic aromatic hydrocarbon (PAH). Total HAP VOC and particulate PAH emissions from a 2008 peat wildfire in North Carolina were estimated, suggesting that peat fires can contribute a large fraction of state-wide HAP emissions.

Effectiveness of inorganic membrane mixture of natural zeolite and portland white cement in purifying of peat water based on turbidity parameter

NASA Astrophysics Data System (ADS)

Elfiana; Fuadi, A.; Diana, S.

2018-04-01

Peat water is water surface that brownish red colour caused by the contained constituents. Solving the peat watercolor problem requires special attention considering the quantity of peat water and suitable to be used to meet the daily needs. This study aims to know the inorganic membrane capability of mix nature zeolite and white Portland cement to purifying the peat water based on turbidity parameter. The study was conducted by varying the composition of nature zeolite (Za) and white Portland cement (Sp) in the ratio of Za: Sp is (25%:75%; 50%:50%; 75%:25%) with zeolite condition activated using HCl 2M and nonactivated zeolite treatments. The result of the characteristic test on membrane morphology using SEM (Scanning Electron Microscope) showed that the pore surface size of the membrane is 2 μm that could classified in microfiltration membrane an organic type. The characteristic test showed also resulted in the density of 0.77 to 0.86 gr/cm3, porosity 26.22% to 35.93%, and permeability 2736.19 to 8428.15. While the water retention capacity is in range of 30.64% to 46.46%, The result of inorganic membrane application on peat water showed turbidity of peat water decreased 94.17%, from 10.3 NTU to 0.6 NTU.

Structure of peat soils and implications for biogeochemical processes and hydrological flow

NASA Astrophysics Data System (ADS)

Rezanezhad, F.; McCarter, C. P. R.; Gharedaghloo, B.; Kleimeier, C.; Milojevic, T.; Liu, H.; Weber, T. K. D.; Price, J. S.; Quinton, W. L.; Lenartz, B.; Van Cappellen, P.

2017-12-01

Permafrost peatlands contain globally important amounts of soil organic carbon and play major roles in global water, nutrient and biogeochemical cycles. The structure of peatland soils (i.e., peat) are highly complex with unique physical and hydraulic properties; where significant, and only partially reversible, shrinkage occurs during dewatering (including water table fluctuations), compression and/or decomposition. These distinct physical and hydraulic properties controls water flow, which in turn affect reactive and non-reactive solute transport (such as, sorption or degradation) and biogeochemical functions. Additionally, peat further attenuates solute migration through molecular diffusion into the inactive pores of Sphagnum dominated peat. These slow, diffusion-limited solute exchanges between the pore regions may give rise to pore-scale chemical gradients and heterogeneous distributions of microbial habitats and activity in peat soils. Permafrost peat plateaus have the same essential subsurface characteristics as other widely organic soil-covered peatlands, where the hydraulic conductivity is related to the degree of decomposition and soil compression. Increasing levels of decomposition correspond with a reduction of effective pore diameter and consequently restrict water and solute flow (by several orders of magnitude in hydraulic conductivity between the ground surface and a depth of 50 cm). In this presentation, we present the current knowledge of key physical and hydraulic properties related to the structure of globally available peat soils and discuss their implications for water storage, flow and the migration of solutes.

Mapping palm oil expansion using SAR to study the impact on the CO2 cycle

NASA Astrophysics Data System (ADS)

Pohl, Christine

2014-06-01

With Malaysia being the second largest palm oil producer in the world and the fact that palm oil ranks first in vegetable oil production on the world market the palm oil industry became an important factor in the country. Along with the expansion of palm oil across the nation causing deforestation of natural rain forest and conversion of peat land into plantation land there are several factors causing a tremendous increase in carbon dioxide (CO2) emissions. Main causes of CO2 emission apart from deforestation and peat-land conversion are the fires to create plantation land plus the fires burning waste products of the plantations itself. This paper describes a project that aims at the development of a remote sensing monitoring system to allow a continuous observation of oil palm plantation activities and expansion in order to be able to quantify CO2 emissions. The research concentrates on developing a spaceborne synthetic aperture radar information extraction system for palm oil plantations in the Tropics. This will lead to objective figures that can be used internationally to create a policy implementation plan to sustainably reduce CO2 emission in the future.

Energy or compost from green waste? - A CO{sub 2} - Based assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kranert, Martin, E-mail: martin.kranert@iswa.uni-stuttgart.d; Gottschall, Ralf; Bruns, Christian

2010-04-15

Green waste is increasingly extracted from the material recycling chain and, as a result of the financial subsidy arising from the German renewable energy law for the generation of energy from renewable raw materials; it is fed into the energy recovery process in biomass power stations. A reduction in climate relevant gases is also linked to the material recovery of green waste - in particular when using composts gained from the process as a new raw material in different types of potting compost and plant culture media as a replacement for peat. Unlike energy recovery, material valorisation is not currentlymore » subsidised. Through the analysis of material and energy valorisation methods for green waste, with particular emphasis on primary resource consumption and CO{sub 2}-balance, it could be determined that the use of green waste for energy generation and its recovery for material and peat replacement purposes can be considered to be on a par. Based on energy recovery or material oriented scenarios, it can be further deduced that no method on its own will achieve the desired outcome and that a combination of recycling processes is more likely to lead to a significant decrease of greenhouse gas emissions.« less

Effect of Peat Moss and Pumice on Douglas Fir Bark based Soilless Substrate Physical and Hydraulic Properties

USDA-ARS?s Scientific Manuscript database

Douglas fir [Pseudotsuga menziesii Mirb.(Franco)] bark (DFB), sphagnum peat moss, and pumice are the most common substrate components used in the Oregon nursery industry. The objective of this study was to document the effect of peat and pumice addition on the physical and hydrological properties o...