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Sample records for peat sphagnum magallanicum

  1. Isotope evidence for N2-fixation in Sphagnum peat bogs

    NASA Astrophysics Data System (ADS)

    Novak, Martin; Jackova, Ivana; Buzek, Frantisek; Stepanova, Marketa; Veselovsky, Frantisek; Curik, Jan; Prechova, Eva

    2016-04-01

    Waterlogged organic soils store as much as 30 % of the world's soil carbon (C), and 15 % of the world's soil nitrogen (N). In the era of climate change, wetlands are vulnerable to increasing temperatures and prolonged periods of low rainfall. Higher rates of microbial processes and/or changing availability of oxygen may lead to peat thinning and elevated emissions of greenhouse gases (mostly CO2, but also CH4 and N2O). Biogeochemical cycling of C and N in peat bogs is coupled. Under low levels of pollution by reactive nitrogen (NO3-, NH4+), increasing N inputs may positively affect C storage in peat. Recent studies in North America and Scandinavia have suggested that pristine bogs are characterized by significant rates of microbial N2 fixation that augments C storage in the peat substrate. We present a nitrogen isotope study aimed at corroborating these findings. We conducted an isotope inventory of N fluxes and pools at two Sphagnum-dominated ombrotrophic peat bogs in the Czech Republic (Central Europe). For the first time, we present a time-series of del15N values of atmospheric input at the same locations as del15N values of living Sphagnum and peat. The mean del15N values systematically increased in the order: input NH4+ (-10.0 ‰) < input NO3- (-7.9 ‰) < peat porewater (-5.6 ‰) < Sphagnum (-5.0 ‰) < shallow peat (-4.2 ‰) < deep peat (-2.2 ‰) < runoff (-1.4 ‰) < porewater N2O (1.4 ‰). Importantly, N of Sphagnum was isotopically heavier than N of the atmospheric input (p < 0.001). If partial incorporation of reactive N from the atmosphere into Sphagnum was isotopically selective, the residual N would have to be isotopically extremely light. Such N, however, was not identified anywhere in the ecosystem. Alternatively, Sphagnum may have contained an admixture of isotopically heavier N from atmospheric N2 (del15N N2 = 0 ‰). We conlude that the N isotope systematics at the two Czech sites is consistent with the concept of significant N2 fixation

  2. Preferential degradation of polyphenols from Sphagnum - 4-Isopropenylphenol as a proxy for past hydrological conditions in Sphagnum-dominated peat

    NASA Astrophysics Data System (ADS)

    Schellekens, Judith; Bindler, Richard; Martínez-Cortizas, Antonio; McClymont, Erin L.; Abbott, Geoffrey D.; Biester, Harald; Pontevedra-Pombal, Xabier; Buurman, Peter

    2015-02-01

    The net accumulation of remains of Sphagnum spp. is fundamental to the development of many peatlands. The effect of polyphenols from Sphagnum on decomposition processes is frequently cited but has barely been studied. The central area of the Rödmossamyran peatland (Sweden) is an open lawn that consists mostly of Sphagnum spp. with a very low contribution from vascular plants. In order to determine the effects of decay on sphagnum phenols, 53 samples of a 2.7 m deep core from this lawn were analysed with pyrolysis gas chromatography-mass spectrometry (pyrolysis-GC-MS) and compared with more traditional decomposition proxies such as C/N ratio, UV light transmission of alkaline peat extracts, and bulk density. Factor analysis of 72 quantified pyrolysis products suggested that the variation in 4-isopropenylphenol was largely determined by aerobic decomposition instead of Sphagnum abundance. In order to evaluate the effects of aerobic decay in Sphagnum peat, down-core records from different climatic regions were compared using molecular markers for plant biopolymers and C/N ratio. These included markers for lignin from vascular plants ((di)methoxyphenols), polyphenols from Sphagnum spp. (4-isopropenylphenol), and cellulose (levoglucosan). Our results indicate that polyphenols from Sphagnum are preferentially degraded over polysaccharides; consequently the variability of the marker for sphagnum acid, 4-isopropenylphenol, was found indicative of decomposition instead of reflecting the abundance of Sphagnum remains. The fact that 4-isopropenylphenol is aerobically degraded in combination with its specificity for Sphagnum spp. makes it a consistent indicator of past hydrological conditions in Sphagnum-dominated peat. In contrast, the variability of C/N records in Sphagnum-dominated peat was influenced by both vegetation shifts and decomposition, and the dominant effect differed between the studied peatlands. Our results provide direction for modelling studies that try to

  3. Soil hydraulic properties of sphagnum moss and peat

    NASA Astrophysics Data System (ADS)

    Weber, Tobias K. D.; Iden, Sascha C.; Scharnagl, Benedikt; Durner, Wolfgang

    2015-04-01

    The moisture state of the vadose zone (acrotelm) of ombrotrophic peatlands decisively determines whether carbon is contained in soil organic matter or released to the atmosphere. As the pore space is variably saturated with water throughout the year, oxygen diffusion, heat, and solute transport and thus the redox state are a function of water content over time. For prediction purposes, the hydrological processes must be epitomised in computer models which establish a link between the terrestrial water cycle and the carbon cycle. This requires a proper representation of effective soil hydraulic properties which are a mandatory input to the Richards equation, the standard model for variably-saturated flow processes in porous media. By applying the Richards equation to peatlands, one assumes that the acrotelm can be conceptualised as a rigid porous material. To test this approximation and select the most adequate set of soil hydraulic property functions, we conducted a series of specifically designed laboratory evaporation experiments on sphagnum moss and decomposed sphagnum peat. Sampling was carried out in five centimeter depth increments of an ombrotrophic bog profile in the Harz mountains. We selected sphagnum moss as it is a predominant plant species colonising bogs of the Boreal. Inverse modelling was used to test the adequacy of different parameterizations of soil hydraulic property functions. We used pressure head data measured by two tensiometers in the objective function to identify soil hydraulic properties. The Richards equation was used as process model. We critically assess the applicability of the van Genuchten/Mualem model, which finds frequent application in peatland hydrology, and discuss alternatives which account for (1) multimodal pore size distributions, (2) physical plausibility towards the dry end, (3) capillary and non-capillary storage and flow, and (4) isothermal flow of water vapour. Finally, our results indicate that applying the Richards

  4. Effect of fire on phosphorus forms in Sphagnum moss and peat soils of ombrotrophic bogs.

    PubMed

    Wang, Guoping; Yu, Xiaofei; Bao, Kunshan; Xing, Wei; Gao, Chuanyu; Lin, Qianxin; Lu, Xianguo

    2015-01-01

    The effect of burning Sphagnum moss and peat on phosphorus forms was studied with controlled combustion in the laboratory. Two fire treatments, a light fire (250 °C) and a severe fire (600 °C), were performed in a muffle furnace with 1-h residence time to simulate the effects of different forest fire conditions. The results showed that fire burning Sphagnum moss and peat soils resulted in losses of organic phosphorus (Po), while inorganic phosphorus (Pi) concentrations increased. Burning significantly changed detailed phosphorus composition and availability, with severe fires destroying over 90% of organic phosphorus and increasing the availability of inorganic P by more than twofold. Our study suggest that, while decomposition processes in ombrotrophic bogs occur very slowly, rapid changes in the form and availability of phosphorus in vegetation and litter may occur as the result of forest fires on peat soils. PMID:24630445

  5. 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

  6. Carbon release from Sphagnum peat during thawing in a montane area in China

    NASA Astrophysics Data System (ADS)

    Wang, Xianwei; Song, Changchun; Wang, Jiaoyue; Miao, Yuqing; Mao, Rong; Song, Yanyu

    2013-08-01

    Soil thawing may affect the turnover of soil organic carbon (C) and the release of C to the atmosphere. Little is known about C release during thawing in the Great Hing'an Mountains, China. Through the incubations, we studied the emissions of CO2 and CH4 during thawing from the Sphagnum moss layer to the permafrost layer under aerobic and anaerobic conditions. Carbon was released quickly during thawing under different conditions. The Sphagnum moss layer produced more CO2 than the other layers. However, there was little CH4 release during thawing in the Sphagnum moss layer and burst of CH4 emissions in the peat and permafrost soils. These bursts include stored CH4 in the frozen samples and productions from microbial activity. The temperature sensitivity during thawing decreased across the freezing point in the Sphagnum moss layer, did not change greatly in the root layer, and increased greatly in the peat and permafrost layers. Changes in soil substrates and enzyme activities may affect C release during thawing.

  7. Modeling Sphagnum moisture stress in response to 21st century climate change using dynamic peat properties

    NASA Astrophysics Data System (ADS)

    Moore, P.; Kettridge, N.; Morris, P. J.; Waddington, J. M.

    2013-12-01

    Sphagnum is associated with wet habitats such as northern peatlands, which may be vulnerable to enhanced 21st century drought due to climate change. We adapted a physically based, 1.5-dimensional (vertical with horizontal interaction in the saturated zone) water-balance model to investigate the role of topographic position and depth-dependence of hydrophysical properties on Sphagnum moisture stress response to current and projected climate conditions in a southern boreal peatland. We parameterized the peat hydrophysical properties using field and lab-based measurements from three adjacent peatlands with different average water table (WT) depths, microtopgraphic variability, and microtopographic patterning; where measurement locations were chosen to take advantage of a long-term WT manipulation that resulted from berm construction in the 1950s. WT level was shown to have a strong control on pore water pressure (ψ), and thus on Sphagnum moisture stress. As a result of the close correspondence between laboratory measured surface peat hydrophysical properties for hummocks and lawns used to parameterize our model, microtopographic position was shown to have a greater impact on Sphagnum moisture stress when using a static surface level. By incorporating a dynamic surface level based on ψ, bulk density, and differences in compressibility between microtopographical elements, Sphagnum moisture stress was shown to be reduced in lawns. The reduction in moisture stress was less than what would be expected based solely on surface adjustment due to the concomitant change in pore-size distribution, which we model based on changes in bulk density. Overall, model behavior suggests that, while ψ maintains equilibrium-profile values relative to the WT level for relatively shallow values, surface ψ becomes non-linearly related to WT level below a value of approximately -0.4 m, thus greatly increasing the likelihood of desiccation under future climate scenarios where growing season

  8. Sphagnum mosses on cutover peat: Moss layer structural controls on water exchanges

    NASA Astrophysics Data System (ADS)

    Price, Jonathan; McCarter, Colin; Ketcheson, Scot

    2013-04-01

    The structure of Sphagnum moss communities strongly affect their ability to retain and redistribute water in a peatland ecosystem. This moss structure varies by species, and within species depending on certain abiotic factors (e.g. shade). On cutover bogs mosses that have regenerated, either spontaneously or through managed restoration, may develop a relatively loose structure that can vary significantly from those growing in undisturbed ecosystems. For example, the structure of a 15-20 cm layer of Sphagnum mosses regenerated over a ten-year period at the "restored" Bois-des-Bel peatland (Quebec, Canada) restricts its ability to sequester carbon and control site scale hydrological fluxes, including E and runoff. Further, the loose structure of the mosses also decreases their soil-water retention and unsaturated hydraulic conductivity, reducing their ability to draw water up from the water table (WT) and to sustain evaporation (E) and photosynthesis. Stark structural differences between moss communities and cutover peat in abandoned (or restored) peatlands strongly affects water exchanges between cutover peat and overlying moss. At relatively dry locations (e.g. WT > 20 cm below the interface of cutover peat) the moss is effectively decoupled from the influence of the WT in the cutover substrate, and must rely on the atmospheric or internally redistributed moisture to hydrate the upper (living) layer. Wetter locations where the moss structure is particularly loose may also exhibit limited connectivity.

  9. Effects of sulphuric compounds on the ATP content of the peat moss Sphagnum fuscum

    SciTech Connect

    Aulio, K.

    1984-01-01

    Luminometric determination of ATP in the photosynthetic tissues of the peat moss Sphagnum fuscum proved to be a suitable technique in studying the effects of bisulphite and sulphate on the metabolism of the mosses. The method has the advantage that it is rapid and easy to perform, and that the results are reliable and equal with those obtained by using other techniques. Bisulphite (HSO/sub 3//sup -/) caused marked reductions in the ATP contents at the 1 mM level, and the 5 mM level was clearly detrimental to the energy metabolism of the mosses. In contrast, sulphate (SO/sub 4//sup 2 -/) increased the ATP contents markedly.

  10. Peat

    USGS Publications Warehouse

    Apodaca, Lori E.

    2013-01-01

    The article looks at the U.S. peat market as of July 2013. Peat is produced from deposits of plant organic materials in wetlands and includes varieties such as reed-sedge, sphagnum moss, and humus. Use for peat include horticultural soil additives, filtration, and adsorbents. Other topics include effects of environmental protection regulations on peat extraction, competition from products such as coir, composted organic waste, and wood products, and peatland carbon sinks.

  11. The role of fungi in the Sphagnum peat wastewater treatment system

    SciTech Connect

    Brooks, J.L.

    1988-01-01

    The lack of suitable soils and the increased building in rural areas has led to the need for alternative onsite wastewater treatment systems. One alternative system utilizes Sphagnum peat to provide a high quality effluent (<10 mg/l BOD5, <6 mg/l nitrate N, and <1 fecal coliform bacteria/100 ml). Treatment efficiencies were greatest when the temperature of the peat was 0-10{degree}C. During this period the organic N and ammonia-N concentrations in the septic tank effluent were reduced by 90-95% and 95-99% respectively; the effluent contained 0.4-1.4 mg/liter organic N and 0.2-1.9 mg/liter ammonia-N. Treatment of the septic tank effluent is attributed to physical filtration, adsorption, and microbiological activity. Microbiological treatment of wastewater has traditionally been attributed to bacteria; however, the cool, acidic, aerobic environment in the peat system favored the growth and activity of fungi over that of bacteria. The fungal population recovered from the system by plating techniques ranged from 1.9 {times} 10{sup 6} to 1.2 {times} 10{sup 9} colony forming units/gram of dry peat. Additional yeast species and zoosporic fungi were recovered from the peat samples by shake-culturing and baiting techniques. The ratio of fungal to bacterial activity, as measured by relative respiration rates, was 8:1 in the winter months and 6:2.5 in the summer. Excessive growth of fungi was controlled by the enchytraeid-worm population which was, in turn, fed upon by skunks, racoons, and birds. Additional nutrients were removed from the system when surface vegetation was harvested. Peat wastewater treatment systems, when properly designed and constructed, may be used effectively on adverse sites; their documented lifespan is ten years and their projected lifespan equals that of conventional soil adsorption systems.

  12. Profiles of Water Content and Pore Size in Sphagnum and Peat, and their Relation to Peat Bog Ecology

    NASA Astrophysics Data System (ADS)

    Hayward, P. M.; Clymo, R. S.

    1982-06-01

    The bog mosses, Sphagnum, form a significant part of the total mass of plants in the world. Their rate of growth depends to a considerable extent on the supply of water to them, and different species occupy characteristic habitats which differ in their ability to supply water. We used the profiles of water content in almost undisturbed cores of two species to infer the size and distribution of spaces around the plants in an attempt to account for the observation that S. papillosum is usually found not far above the water table, while S. capilliforlium is usually found on hummocks well above the water table. Profiles of water content were recorded non-destructively from 30 cm diameter cores of Sphagnum and underlying peat, with use of the absorbance of the soft gamma radiation of 241Am. The distribution of water-fillable spaces of different size was inferred from profiles with the water table at different distances, to a maximum of 150 cm, below the surface. The larger spaces, which are the main path of water transport, are outside the plant cell walls: between leaves and between pendent branches and stems. The mean radius of such spaces around the hummock species S. capillifolium is smaller than that around S. papillosum. For a given depth of water table the water content of the apical tuft of branches, where growth occurs, is greater in the hummock species than it is in the lawn species. Of ecological importance is that, for a given water content in the apex, the water table is at a greater depth below the hummock species than it is below the lawn species. As the water table rises and falls, so the water content of both species shows hysteresis as large as the difference between them. The ecological significance of this and the need for measurements while water is flowing are discussed.

  13. The narrow endemic Norwegian peat moss Sphagnum troendelagicum originated before the last glacial maximum

    PubMed Central

    Stenøien, H K; Shaw, A J; Stengrundet, K; Flatberg, K I

    2011-01-01

    It is commonly found that individual hybrid, polyploid species originate recurrently and that many polyploid species originated relatively recently. It has been previously hypothesized that the extremely rare allopolyploid peat moss Sphagnum troendelagicum has originated multiple times, possibly after the last glacial maximum in Scandinavia. This conclusion was based on low linkage disequilibrium in anonymous genetic markers within natural populations, in which sexual reproduction has never been observed. Here we employ microsatellite markers and chloroplast DNA (cpDNA)-encoded trnG sequence data to test hypotheses concerning the origin and evolution of this species. We find that S. tenellum is the maternal progenitor and S. balticum is the paternal progenitor of S. troendelagicum. Using various Bayesian approaches, we estimate that S. troendelagicum originated before the Holocene but not before c. 80 000 years ago (median expected time since speciation 40 000 years before present). The observed lack of complete linkage disequilibrium in the genome of this species suggests cryptic sexual reproduction and recombination. Several lines of evidence suggest multiple origins for S. troendelagicum, but a single origin is supported by approximate Bayesian computation analyses. We hypothesize that S. troendelagicum originated in a peat-dominated refugium before last glacial maximum, and subsequently immigrated to central Norway by means of spore flow during the last thousands of years. PMID:20717162

  14. Recombination and introgression of nuclear and chloroplast genomes between the peat mosses, Sphagnum capillifolium and Sphagnum quinquefarium.

    PubMed

    Natcheva, Rayna; Cronberg, Nils

    2007-02-01

    Haploid hybrid gametophytes are often present at low frequencies in sympatric populations of Sphagnum capillifolium and Sphagnum quinquefarium. We used intersimple sequence repeat (ISSR) markers and polymerase chain reaction-restriction fragment length polymorphism of the trnL(UAA) intron of the chloroplast genome to reveal the nuclear and chloroplast composition of mature hybrid gametophytes from natural populations and of gametophytes derived from spores of hybrid sporophytes collected in nature. Asymmetrical nuclear inheritance was found in the progeny of the hybrid sporophytes, indicating that only spores with a low level of recombination of parental genomes were viable. A similarly skewed nuclear composition was found among the naturally occurring hybrid gametophytes. All hybrid genomes contained a larger proportion of S. capillifolium ISSR markers, combined with only two to five S. quinquefarium markers together with a chloroplast haplotype derived from S. quinquefarium. In this way, a pattern resembling introgression is created within a single generation. Some individuals possessed nuclear genomes typical for S. capillifolium in combination with the chloroplast haplotype of S. quinquefarium, possibly indicating backcrossing. Our results indicate that hybridization between S. capillifolium and S. quinquefarium is relatively common, but the resistance of large parts of the genome against heterospecific genes maintains the genetic distinctness of the species. Further evolutionary and phylogenetic consequences of restricted interspecific gene exchange are discussed. PMID:17284213

  15. Greenhouse gas exchange of rewetted bog peat extraction sites and a Sphagnum cultivation site in northwest Germany

    NASA Astrophysics Data System (ADS)

    Beyer, C.; Höper, H.

    2015-04-01

    During the last decades an increasing area of drained peatlands has been rewetted. Especially in Germany, rewetting is the principal treatment on cutover sites when peat extraction is finished. The objectives are bog restoration and the reduction of greenhouse gas (GHG) emissions. The first sites were rewetted in the 1980s. Thus, there is a good opportunity to study long-term effects of rewetting on greenhouse gas exchange, which has not been done so far on temperate cutover peatlands. Moreover, Sphagnum cultivating may become a new way to use cutover peatlands and agriculturally used peatlands as it permits the economical use of bogs under wet conditions. The climate impact of such measures has not been studied yet. We conducted a field study on the exchange of carbon dioxide, methane and nitrous oxide at three rewetted sites with a gradient from dry to wet conditions and at a Sphagnum cultivation site in NW Germany over the course of more than 2 years. Gas fluxes were measured using transparent and opaque closed chambers. The ecosystem respiration (CO2) and the net ecosystem exchange (CO2) were modelled at a high temporal resolution. Measured and modelled values fit very well together. Annually cumulated gas flux rates, net ecosystem carbon balances (NECB) and global warming potential (GWP) balances were determined. The annual net ecosystem exchange (CO2) varied strongly at the rewetted sites (from -201.7 ± 126.8 to 29.7± 112.7g CO2-C m-2 a-1) due to differing weather conditions, water levels and vegetation. The Sphagnum cultivation site was a sink of CO2 (-118.8 ± 48.1 and -78.6 ± 39.8 g CO2-C m-2 a-1). The annual CH4 balances ranged between 16.2 ± 2.2 and 24.2 ± 5.0g CH4-C m-2 a-1 at two inundated sites, while one rewetted site with a comparatively low water level and the Sphagnum farming site show CH4 fluxes close to 0. The net N2O fluxes were low and not significantly different between the four sites. The annual NECB was between -185.5 ± 126.9 and 49

  16. Greenhouse gas emissions from rewetted bog peat extraction sites and a Sphagnum cultivation site in Northwest Germany

    NASA Astrophysics Data System (ADS)

    Beyer, C.; Höper, H.

    2014-03-01

    . The yearly GWP100 balances ranged from -280.5 ± 465.2 to 644.5 ± 413.6 g CO2-eq. m-2 a-1 at the rewetted sites. In contrast, the Sphagnum farming site had a cooling impact on the climate in both years (-356.8 ± 176.5 and -234.9 ± 145.9 g CO2-C m-2 a-1). If the exported carbon through the harvest of the Sphagnum biomass and the additional CO2 emission from the decay of the organic material is considered, the NECB and GWP100 balances are near neutral. Peat mining sites are likely to become net carbon sinks and a peat accumulating ("growing") peatland within 30 years after rewetting, but the GWP100 balance may still be positive. A recommended measure for rewetting is to achieve a water level of a few centimetres below ground surface. Sphagnum farming is a climate friendly alternative to conventional commercial use of bogs. A year round constant water level of a few centimetres below ground level should be maintained.

  17. Comparative characteristic of the sphagnum moss and peat of upland bogs in Siberia, Russia and central part of Germany

    NASA Astrophysics Data System (ADS)

    Mezhibor, Antonina; Podkozlin, Ivan

    2013-04-01

    This research represents the results of the ICP-MS study for the moss and peat samples from two upland bogs of Germany and one bog from Siberia, Russia (Tomsk region). Moss and upland peat are widely used for ecological studies. These substances enable to detect atmospheric pollution because of the peculiar structure of sphagnum moss. According to the obtained results, we can resume that moss and peat in Tomsk region are more enriched in such chemical elements as Cr, Fe, As, Sr, Y, Zr, Ba, La, Ce, Nd, Sm, Eu, Tb, Yb, Lu, Hf, Hg, Th, and U. The samples from Germany are more enriched in Mn, Cu, Zn, and Se. The geochemical composition of the bogs reflects the specificity of industries that pollute the atmosphere with definite chemical elements. Thus, REE, Th and U in the moss and peat of Tomsk region can originate from nuclear facility near the Tomsk city. Coal combustion in power stations can be the source of Cr, As, Sr and REE as well. Mn, Cu, Zn, and Se possibly can originate from metallurgical facilities in Germany.

  18. Predicting Calcite (CaCO3) Requirements of Sphagnum Peat Moss from pH Titration Curves

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Liming materials are required to neutralize acidity in peat moss to make it a suitable substrate for growing container crops. A series of time-consuming incubations of peat:lime mixtures are typically used to determine the liming rate to achieve a desired pH. Our objective was to evaluate the util...

  19. Nitrous oxide emission potentials of Burkholderia species isolated from the leaves of a boreal peat moss Sphagnum fuscum.

    PubMed

    Nie, Yanxia; Li, Li; Wang, Mengcen; Tahvanainen, Teemu; Hashidoko, Yasuyuki

    2015-01-01

    Using a culture-based nitrous oxide (N2O) emission assay, three active N2O emitters were isolated from Sphagnum fuscum leaves and all identified as members of Burkholderia. These isolates showed N2O emission in the medium supplemented with [Formula: see text] but not with [Formula: see text], and Burkholderia sp. SF-E2 showed the most efficient N2O emission (0.20 μg·vial(-1)·day(-1)) at 1.0 mM KNO3. In Burkholderia sp. SF-E2, the optimum pH for N2O production was 5.0, close to that of the phyllosphere of Sphagnum mosses, while the optimum temperature was uniquely over 30 °C. The stimulating effect of additional 1.5 mM sucrose on N2O emission was ignorable, but Burkholderia sp. SF-E2 upon exposure to 100 mg·L(-1) E-caffeic acid showed uniquely 67-fold higher N2O emission. All of the three N2O emitters were negative in both acetylene inhibition assay and PCR assay for nosZ-detection, suggesting that N2O reductase or the gene itself is missing in the N2O-emitting Burkholderia. PMID:26167675

  20. The effects of quantitative fecundity in the haploid stage on reproductive success and diploid fitness in the aquatic peat moss Sphagnum macrophyllum.

    PubMed

    Johnson, M G; Shaw, A J

    2016-06-01

    A major question in evolutionary biology is how mating patterns affect the fitness of offspring. However, in animals and seed plants it is virtually impossible to investigate the effects of specific gamete genotypes. In bryophytes, haploid gametophytes grow via clonal propagation and produce millions of genetically identical gametes throughout a population. The main goal of this research was to test whether gamete identity has an effect on the fitness of their diploid offspring in a population of the aquatic peat moss Sphagnum macrophyllum. We observed a heavily male-biased sex ratio in gametophyte plants (ramets) and in multilocus microsatellite genotypes (genets). There was a steeper relationship between mating success (number of different haploid mates) and fecundity (number of diploid offspring) for male genets compared with female genets. At the sporophyte level, we observed a weak effect of inbreeding on offspring fitness, but no effect of brood size (number of sporophytes per maternal ramet). Instead, the identities of the haploid male and haploid female parents were significant contributors to variance in fitness of sporophyte offspring in the population. Our results suggest that intrasexual gametophyte/gamete competition may play a role in determining mating success in this population. PMID:26905464

  1. 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.

  2. Testing the sensitivity of stable carbon isotopes of sub-fossil Sphagnum cellulose to past climate variability: a two millennia high resolution stable carbon isotope time series from the peat deposit "Dürres Maar", Germany

    NASA Astrophysics Data System (ADS)

    Moschen, Robert; Kühl, Norbert; Peters, Sabrina; Vos, Heinz; Lücke, Andreas

    2010-05-01

    Peat deposits are terrestrial archives of environmental changes and climate dynamics over time. They are widely distributed and cover a large part of the earth's land surface often within human habitat and, thus, form an excellent basis for evaluating ecosystem and climate dynamics by multiple geochemical and biological methods. Records of the stable carbon composition of cellulose separately extracted from selected Sphagnum plant components (δ13CSphagnum) from the kettle-hole type peat deposit of 'Dürres Maar' are presented. Manually separated Sphagnum stems, branches and the small leaves covering Sphagnum branches were used for cellulose extraction and subsequent isotope measurements, because intra-plant δ13CSphagnum variability between different physical components of individual modern plants has been described (Loader et al. 2007). We observed the same isotopic offset between single plant components of sub-fossil Sphagnum plant components which is statistically highly significant and observable down-core (Moschen et al. 2009). Using the size fraction of 355-630 μm, which almost exclusively consists of single Sphagnum leaves, allows to derive environmental and climate signals based on a plant response to external controls, presumably including temperature and relative humidity. Because down-core changes in the ratio of different plant components in the peat profile seem probable, erroneous interpretations of isotope records are likely if no differentiation into single Sphagnum plant components is possible. A high resolution time series of δ13CSphagnum is presented covering the last two millennia, tracing decadal to sub-decadal past environmental and climate dynamics. The thickness of the water film surrounding the chloroplasts of Sphagnum plants has been suggested as the most important factor influencing δ13CSphagnum. This points to bog surface wetness which is primarily driven by precipitation and evaporation temperature as the major control of δ13

  3. An analysis of Late Quaternary eruption frequency as recorded by tephra-fall records from 25 sedge- Sphagnum peat cores recovered from the Kenai Peninsula, Alaska

    NASA Astrophysics Data System (ADS)

    Deruwe, A.; Wallace, K.; Berg, E.; McDonnell, K.; Loso, M.

    2007-12-01

    Tephra fall (volcanic ash) is considered the principal hazard from Aleutian Arc volcanoes in terms of volume, distribution, and environmental impact. Over sixty percent of Alaska's human population resides in the Cook Inlet region, where ash fall from nearby volcanoes, including Hayes, Spurr/Crater Peak, Redoubt, Iliamna, and Augustine pose the greatest volcanic risk. Alaska's Kenai Peninsula is located generally downwind of Cook Inlet volcanoes (approx. 85 to 400 km) and other active Aleutian Arc volcanoes. Previous studies have shown that Holocene-age tephra fall is well preserved in post-glacial sediments from this region. Such studies have used individual stratigraphic records to estimate tephra-fall frequency on a regional scale, although it is unclear whether those data reflect actual eruption frequency or are biased by paleo-wind direction, basin features, geomorphology, etc. These studies have shown highly discrepant ash-fall frequency records, which may result from the restricted number of study sites (typically one or two), the lack of spatial coverage, and/or the limited preservation potential of a given location. In order to evaluate actual eruption frequency as reflected by tephra fall, our study incorporates a wider geographic range and a greater number of sample locations than previous studies. We recovered and examined 25 sedge- Sphagnum peat cores from a northeast to southwest transect of the Kenai Peninsula, directly parallel to the Cook Inlet volcanoes and covering an area of 8,050 km2 (70 km wide by 115 km long). Magnetic susceptibility (MS), petrographic and electron microprobe analyses, and radiocarbon ages have been utilized to identify, characterize, and correlate tephra deposits among cores. A total of 221 undifferentiated tephra-fall layers are preserved in our cores, of which approximately 80 percent were identified visually and 20 percent were identified by MS peaks and petrographic verification. Eighty AMS radiocarbon ages, ranging from

  4. Peat

    USGS Publications Warehouse

    Jasinski, S.M.

    2000-01-01

    The United States continued to be significant producer and consumer of peat for horticultural and industrial applications in 1999. Florida, Michigan and Minnesota were the largest producing states, in order of output.

  5. Dust is the dominant source of "heavy metals" to peat moss (Sphagnum fuscum) in the bogs of the Athabasca Bituminous Sands region of northern Alberta.

    PubMed

    Shotyk, William; Bicalho, Beatriz; Cuss, Chad W; Duke, M John M; Noernberg, Tommy; Pelletier, Rick; Steinnes, Eiliv; Zaccone, Claudio

    2016-01-01

    Sphagnum fuscum was collected from twenty-five ombrotrophic (rain-fed) peat bogs surrounding open pit mines and upgrading facilities of Athabasca Bituminous Sands (ABS) in northern Alberta (AB) in order to assess the extent of atmospheric contamination by trace elements. As a control, this moss species was also collected at a bog near Utikuma (UTK) in an undeveloped part of AB and 264km SW of the ABS region. For comparison, this moss was also collected in central AB, in the vicinity of the City of Edmonton which is approximately 500km to the south of the ABS region, from the Wagner Wetland which is 22km W of the City, from Seba Beach (ca. 90km W) and from Elk Island National Park (ca. 45km E). All of the moss samples were digested and trace elements concentrations determined using ICP-SMS at a commercial laboratory, with selected samples also analyzed using instrumental neutron activation analysis at the University of Alberta. The mosses from the ABS region yielded lower concentrations of Ag, As, Bi, Cd, Cu, Pb, Sb, Tl, and Zn compared to the moss from the Edmonton area. Concentrations of Ni and Mo in the mosses were comparable in these two regions, but V was more abundant in the ABS samples. Compared with the surface vegetation of eight peat cores collected in recent years from British Columbia, Ontario, Quebec and New Brunswick, the mean concentrations of Ag, As, Bi, Cd, Cu, Mo, Ni, Pb, Sb, Tl and Zn in the mosses from the ABS region are generally much lower. In fact, the concentrations of these trace elements in the samples from the ABS region are comparable to the corresponding values in forest moss from remote regions of central and northern Norway. Lithophile element concentrations (Ba, Be, Ga, Ge, Li, Sc, Th, Ti, Zr) explain most of the variation in trace metal concentrations in the moss samples. The mean concentrations of Th and Zr are greatest in the moss samples from the ABS region, reflecting dust inputs to the bogs from open pit mines, aggregate

  6. Peat

    USGS Publications Warehouse

    Jasinski, S.M.

    1998-01-01

    The United States continued as a significant producer and consumer of peat for horticultural, agricultural and industrial applications in 1997. Several operations in the Great Lakes and the Southeast regions dominated US production. Florida, Michigan and Minnesota were the largest producing states.

  7. Peat

    USGS Publications Warehouse

    Jasinski, S.M.

    2003-01-01

    Peat is a natural organic material of botanical origin and commercial significance. Peatlands are situated predominately in shallow wetland areas of the Northern Hemisphere. Commercial deposits are formed from the gradual decomposition of plant matter under anaerobic conditions over about a 5,000-year period.

  8. Peat

    USGS Publications Warehouse

    Apodaca, L.E.

    2012-01-01

    In 2011, domestic production of peat, excluding Alaska, was estimated to be 605 kt (667,000 st), compared with 628 kt (629,000 st) in 2010. In 2011, imports increased to 1.1. Mt (1.2 million st) compared with 947 kt (1 million st) in 2010, and exports were estimated to have decreased to 39 kt (43,000 st) in 2011. U.S. apparent consumption for 2011 was estimated to have increased to 1.6 Mt (1.7 million st). World production was estimated to be about 22 Mt (24 million st) in 2011, which was 6 percent lower than 2010.

  9. Peat

    USGS Publications Warehouse

    Apodaca, L.E.

    2010-01-01

    In 2009, domestic production of peat, excluding Alaska, was estimated to be 610 kt (672,000 st), compared with 615 kt (678,000 st) in 2008. In 2009, imports decreased to 906 kt (999,000 st) compared with 936 kt (1 million st) in 2008, and exports were estimated to have increased to 77 kt (85,000 st) in 2009. U.S. apparent consumption for 2009 was estimated to be about the same as in 2008. World production was estimated to be about 25 Mt (27.5 million st) in 2009, which is about the same as 2008.

  10. Peat

    USGS Publications Warehouse

    Apodaca, L.E.

    2013-01-01

    In 2012, domestic production of peat, excluding Alaska, was estimated to be 560 kt (617,000 st), compared with 568 kt (626,000 st) in 2011. In 2012, imports decreased to 940 kt (1 million st) compared with 982 kt (1.1 million st) in 2011, and exports were estimated to have increased to 75 kt (82,600 st) in 2012. U.S. apparent consumption for 2012 was estimated to have remained the same as that of 2011. World production was estimated to be about 27 Mt (30 million st) in 2012, which was slightly higher than 2011.

  11. Peat

    USGS Publications Warehouse

    Apodaca, L.E.

    2011-01-01

    In 2010, domestic production of peat, excluding Alaska, was estimated to be 612 kt (674,600 st), compared with 609 kt (671,300 st) in 2009. In 2010, imports increased to 947 kt (1.04 million st), compared with 906 kt (998,600 st) in 2009. Exports were estimated to have decreased to 69 kt (76,000 st) in 2010. U.S. apparent consumption for 2010 was estimated to have increased to 1.5 Mt (1.65 million st). World production was estimated to be about 23 Mt (25 million st) in 2010, which is 8 percent lower than in 2009.

  12. The Sphagnum microbiome: new insights from an ancient plant lineage.

    PubMed

    Kostka, Joel E; Weston, David J; Glass, Jennifer B; Lilleskov, Erik A; Shaw, A Jonathan; Turetsky, Merritt R

    2016-07-01

    57 I. 57 II. 58 III. 59 IV. 59 V. 61 VI. 62 63 References 63 SUMMARY: Peat mosses of the genus Sphagnum play a major role in global carbon storage and dominate many northern peatland ecosystems, which are currently being subjected to some of the most rapid climate changes on Earth. A rapidly expanding database indicates that a diverse community of microorganisms is intimately associated with Sphagnum, inhabiting the tissues and surface of the plant. Here we summarize the current state of knowledge regarding the Sphagnum microbiome and provide a perspective for future research directions. Although the majority of the microbiome remains uncultivated and its metabolic capabilities uncharacterized, prokaryotes and fungi have the potential to act as mutualists, symbionts, or antagonists of Sphagnum. For example, methanotrophic and nitrogen-fixing bacteria may benefit the plant host by providing up to 20-30% of Sphagnum carbon and nitrogen, respectively. Next-generation sequencing approaches have enabled the detailed characterization of microbiome community composition in peat mosses. However, as with other ecologically or economically important plants, our knowledge of Sphagnum-microbiome associations is in its infancy. In order to attain a predictive understanding of the role of the microbiome in Sphagnum productivity and ecosystem function, the mechanisms of plant-microbiome interactions and the metabolic potential of constituent microbial populations must be revealed. PMID:27173909

  13. Minerals yearbook, 1988: peat

    SciTech Connect

    Cantrell, R.L.

    1988-01-01

    U.S. peat production within the 48 contiguous States declined 6% in 1988. Producers' sales volume and average price received per ton, decreased 3% and 2%, respectively. Ending stocks at the producer level increased 5%. Apparent domestic consumption was 5% below the record 1.5 million tons established during 1986 and 1987. Peat imports increased 15% and reached a record 0.6 million tons, representing 40% of apparent domestic consumption. Canada shipped over 99% of the total. Sphagnum moss sales tonnage increased 142% during the year principally due to development of new high-quality deposits in Minnesota. A significant decline in humus production and sales was experienced.

  14. Variety in dustiness and hygiene quality of peat bedding.

    PubMed

    Airaksinen, Sanna; Heiskanen, Minna-Liisa; Heinonen-Tanski, Helvi; Laitinen, Juha; Laitinen, Sirpa; Linnainmaa, Markku; Rautiala, Sirpa

    2005-01-01

    Respiratory exposure to organic dust induces chronic pulmonary diseases both in farmers and horses. The aim of this study was to examine the variation of dustiness and hygiene quality of peat moss bedding. Materials studied were weakly decomposed sphagnum peat (A), weakly decomposed sphagnum peat warmed up in storage (> 30 degrees C) (B) and two more decomposed few-flowered sedge peats (C and D). The geometric mean of mesophilic fungi, thermotolerant fungi and thermophilic actinomycetes were determined from the material. Samples of inhalable dust and endotoxins were collected with IOM samplers and respirable dust with 10M foam samplers when the peat was rotated in a cylinder. The number of particles was detected with an optical particle counter. An LAL assay was used for analysing endotoxins from the filter samples. There were differences in the hygiene quality and dustiness between peat materials (p < 0.01). The geometric mean of fungi was smallest in material A. Warming-up increased the number of fungi in sphagnum peat, but on the other hand, it decreased the content of endotoxin (p < 0.01). Few-flowered peat materials contained thermophilic actinomycetes and material D also contained Aspergillus fumigatus. The concentrations of inhalable dust, respirable dust and the number of particles were smaller in the few-flowered peats (C-D) than in the sphagnum peats (A-B). It is concluded that there are differences in the dustiness and hygiene quality of peat bedding. PMID:16028867

  15. "Whole Tree", a Promising Alternative to Traditional Peat-based Greenhouse Substrates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Greenhouse crops, with few exceptions, are grown in substrates made up primarily of Canadian sphagnum peat. Of major concern is that peat is a non-renewable resource which at some point in the future will be depleted. Another concern is the increased cost of peat due to the rise in transportation c...

  16. Spectral reflectance measurements in the genus Sphagnum

    SciTech Connect

    Vogelmann, J.E.; Moss, D.M. . Complex Systems/Institute for the Study of Earth Oceans and Space)

    1993-09-01

    High-spectral resolution reflectance data were acquired in the laboratory for four species of Sphagnum (peat moss): S. cuspidatum, S. papillosum, S. fallax, and S. capillifolium. All four species had different spectral reflectance properties. Species differences were noted especially in the visible portion of the spectrum from 0.45 [mu]m to 0.70 [mu]m; some major spectral differences were also noted in the near infrared. Samples analyzed had much lower reflectance than typical green vegetation in the midinfrared region of the spectrum from 1.30 [mu]m to 2.40 [mu]m. In addition, Sphagnum had very pronounced water-related absorption features at about 1.00m [mu] and 1.20 [mu]m, unlike typical green vegetation. Spectral data acquired as samples were dried indicated large spectral increases with increasing dryness, especially in the midinfrared. Simulated Landsat Thematic Mapper 5/4 band ratio data were linearly related to the log of wet weight/dry weight. Reflectance from vegetation in the midinfrared region of the electromagnetic spectrum is strongly modified by water content. Peatlands are major sources of global methane and it has been found that methane evolution within these peatlands is related to water status within these peatlands is related to water status within the wetland. It may be possible to indirectly estimate methane flux using remote sensing data.

  17. Moisture content measurements of moss (Sphagnum spp.) using commercial sensors

    USGS Publications Warehouse

    Yoshikawa, K.; Overduin, P.P.; Harden, J.W.

    2004-01-01

    Sphagnum (spp.) is widely distributed in permafrost regions around the arctic and subarctic. The moisture content of the moss layer affects the thermal insulative capacity and preservation of permafrost. It also controls the growth and collapse history of palsas and other peat mounds, and is relevant, in general terms, to permafrost thaw (thermokarst). In this study, we test and calibrate seven different soil moisture sensors for measuring the moisture content of Sphagnum moss under laboratory conditions. The soil volume to which each probe is sensitive is one of the important parameters influencing moisture measurement, particularly in a heterogeneous medium such as moss. Each sensor has a unique response to changing moisture content levels, solution salinity, moss bulk density and to the orientation (structure) of the Sphagnum relative to the sensor. All of the probes examined here require unique polynomial calibration equations to obtain moisture content from probe output. We provide polynomial equations for dead and live Sphagnum moss (R2 > 0.99. Copyright ?? 2004 John Wiley & Sons, Ltd.

  18. The peats of Costa Rica

    SciTech Connect

    Obando A, L.; Malavassi R, L.; Ramirez E, O. ); Cohen, A. . Dept. of Geological Sciences); Raymond, R. Jr.; Thayer, G.R. )

    1991-04-01

    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 the 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.

  19. Simultaneous high C fixation and high C emissions in Sphagnum mires

    NASA Astrophysics Data System (ADS)

    Harpenslager, S. F.; van Dijk, G.; Kosten, S.; Roelofs, J. G. M.; Smolders, A. J. P.; Lamers, L. P. M.

    2015-08-01

    Peatlands play an important role in the global carbon (C) cycle due to their large C storage potential. Their C sequestration rates, however, highly vary depending on climatic and geohydrological conditions. Transitional mires are often characterised by floating peat with infiltration of buffered groundwater or surface water. Sphagnum mosses grow on top, producing recalcitrant organic matter and fuelling large C stocks. As Sphagnum species strongly differ in their tolerance to the higher pH in these mires, their species composition can be expected to influence C dynamics in transitional mires. We therefore experimentally determined growth and net C sequestration rates for four different Sphagnum species (Sphagnum squarrosum, S. palustre, S. fallax and S. magellanicum) in aquaria, with floating peat influenced by the infiltration of buffered water. Surprisingly, even though the first three species increased their biomass, the moss-covered peat still showed a net efflux of CO2 that was up to 3 times higher than that of bare peat. This species-dependent C release could be explained by Sphagnum's active lowering of the pH, which triggers the chemical release of CO2 from bicarbonate. Our results clearly illustrate that high Sphagnum biomass production may still coincide with high C emission. These counterintuitive C dynamics in mire succession seem to be the result of both species- and biomass-dependent acidification and buffered water infiltration. Together, these processes can explain part of the large variation in C fluxes (ranging from C sequestration to C release) reported for pristine mires in the literature.

  20. Simultaneous high C fixation and high C emissions in Sphagnum mires

    NASA Astrophysics Data System (ADS)

    Harpenslager, S. F.; van Dijk, G.; Kosten, S.; Roelofs, J. G. M.; Smolders, A. J. P.; Lamers, L. P. M.

    2015-03-01

    Peatlands play an important role in the global carbon (C) cycle due to their large C storage potential. Their C sequestration rates, however, highly vary depending on climatic and geohydrological conditions. Transitional mires are often characterised by floating peat with infiltration of buffered groundwater or surface water. On top, Sphagnum mosses grow, producing recalcitrant organic matter and fuelling the large C stocks. As Sphagnum species strongly differ in their tolerance to the higher pH in these mires, their species composition can be expected to influence C dynamics in transitional mires. We therefore experimentally determined growth and net C sequestration rates for four different Sphagnum species (Sphagnum squarrosum, S. palustre, S. fallax and S. magellanicum) in aquaria, with floating peat influenced by the infiltration of buffered water. Surprisingly, even though the first three species increased their biomass, the moss-covered peat still showed a net efflux of CO2 that was up to three times higher than that of bare peat. This species-dependent C release could be explained by Sphagnum's active lowering of the pH, which triggers the chemical release of CO2 from bicarbonate. Our results clearly illustrate that high Sphagnum biomass production may still coincide with high C emission. These counterintuitive C dynamics in mire succession seem to be the result of both species- and biomass-dependent acidification and buffered water infiltration. Together, these processes can explain part of the large variation in C fluxes (ranging from C sequestration to C release) reported for pristine mires in literature.

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

    USGS Publications Warehouse

    Raymond, R., Jr.; 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.

  2. 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.

  3. The Sphagnum microbiome supports bog ecosystem functioning under extreme conditions.

    PubMed

    Bragina, Anastasia; Oberauner-Wappis, Lisa; Zachow, Christin; Halwachs, Bettina; Thallinger, Gerhard G; Müller, Henry; Berg, Gabriele

    2014-09-01

    Sphagnum-dominated bogs represent a unique yet widely distributed type of terrestrial ecosystem and strongly contribute to global biosphere functioning. Sphagnum is colonized by highly diverse microbial communities, but less is known about their function. We identified a high functional diversity within the Sphagnum microbiome applying an Illumina-based metagenomic approach followed by de novo assembly and MG-RAST annotation. An interenvironmental comparison revealed that the Sphagnum microbiome harbours specific genetic features that distinguish it significantly from microbiomes of higher plants and peat soils. The differential traits especially support ecosystem functioning by a symbiotic lifestyle under poikilohydric and ombrotrophic conditions. To realise a plasticity-stability balance, we found abundant subsystems responsible to cope with oxidative and drought stresses, to exchange (mobile) genetic elements, and genes that encode for resistance to detrimental environmental factors, repair and self-controlling mechanisms. Multiple microbe-microbe and plant-microbe interactions were also found to play a crucial role as indicated by diverse genes necessary for biofilm formation, interaction via quorum sensing and nutrient exchange. A high proportion of genes involved in nitrogen cycle and recycling of organic material supported the role of bacteria for nutrient supply. 16S rDNA analysis indicated a higher structural diversity than that which had been previously detected using PCR-dependent techniques. Altogether, the diverse Sphagnum microbiome has the ability to support the life of the host plant and the entire ecosystem under changing environmental conditions. Beyond this, the moss microbiome presents a promising bio-resource for environmental biotechnology - with respect to novel enzymes or stress-protecting bacteria. PMID:25113243

  4. A novel framework for quantifying past methane recycling by Sphagnum-methanotroph symbiosis using carbon and hydrogen isotope ratios of leaf wax biomarkers

    NASA Astrophysics Data System (ADS)

    Nichols, Jonathan E.; Isles, Peter D. F.; Peteet, Dorothy M.

    2014-05-01

    concentration of atmospheric methane is strongly linked to variations in Earth's climate. Currently, we can directly reconstruct the total atmospheric concentration of methane, but not individual terms of the methane cycle. Northern wetlands, dominated by Sphagnum, are an important contributor of atmospheric methane, and we seek to understand the methane cycle in these systems. We present a novel method for quantifying the proportion of carbon Sphagnum assimilates from its methanotrophic symbionts using stable isotope ratios of leaf-wax biomarkers. Carbon isotope ratios of Sphagnum compounds are determined by two competing influences, water content and the isotope ratio of source carbon. We disentangled these effects using a combined hydrogen and carbon isotope approach. We constrained Sphagnum water content using the contrast between the hydrogen isotope ratios of Sphagnum and vascular plant biomarkers. We then used Sphagnum water content to calculate the carbon isotope ratio of Sphagnum's carbon pool. Using a mass balance equation, we calculated the proportion of recycled methane contributed to the Sphagnum carbon pool, "PRM." We quantified PRM in peat monoliths from three microhabitats in the Mer Bleue peatland complex. Modern studies have shown that water table depth and vegetation have strong influences on the peatland methane cycle on instrumental time scales. With this new approach, δ13C of Sphagnum compounds are now a useful tool for investigating the relationships among hydrology, vegetation, and methanotrophy in Sphagnum peatlands over the time scales of entire peatland sediment records, vital to our understanding of the global carbon cycle through the Late Glacial and Holocene.

  5. A Novel Framework for Quantifying past Methane Recycling by Sphagnum-Methanotroph Symbiosis Using Carbon and Hydrogen Isotope Ratios of Leaf Wax Biomarkers

    NASA Technical Reports Server (NTRS)

    Nichols, Jonathan E.; Isles, Peter D. F.; Peteet, Dorothy M.

    2014-01-01

    The concentration of atmospheric methane is strongly linked to variations in Earth's climate. Currently, we can directly reconstruct the total atmospheric concentration of methane, but not individual terms of the methane cycle. Northern wetlands, dominated by Sphagnum, are an important contributor of atmospheric methane, and we seek to understand the methane cycle in these systems. We present a novel method for quantifying the proportion of carbon Sphagnum assimilates from its methanotrophic symbionts using stable isotope ratios of leaf-wax biomarkers. Carbon isotope ratios of Sphagnum compounds are determined by two competing influences, water content and the isotope ratio of source carbon. We disentangled these effects using a combined hydrogen and carbon isotope approach. We constrained Sphagnum water content using the contrast between the hydrogen isotope ratios of Sphagnum and vascular plant biomarkers. We then used Sphagnum water content to calculate the carbon isotope ratio of Sphagnum's carbon pool. Using a mass balance equation, we calculated the proportion of recycled methane contributed to the Sphagnum carbon pool, 'PRM.' We quantified PRM in peat monoliths from three microhabitats in the Mer Bleue peatland complex. Modern studies have shown that water table depth and vegetation have strong influences on the peatland methane cycle on instrumental time scales. With this new approach, delta C-13 of Sphagnum compounds are now a useful tool for investigating the relationships among hydrology, vegetation, and methanotrophy in Sphagnum peatlands over the time scales of entire peatland sediment records, vital to our understanding of the global carbon cycle through the Late Glacial and Holocene.

  6. Biochar as a growing media additive and peat substitute

    NASA Astrophysics Data System (ADS)

    Steiner, C.; Harttung, T.

    2014-09-01

    Environmental concerns raised the demand for alternative growing media substituting Sphagnum peat. However growing media formulations still depend on peat and alternatives are limited. Biochar is carbonized plant material and could be an appropriate additive or even substitute for Sphagnum peat. Freshly produced, it is free from pathogens, has a low nutrient content (if produced from nutrient-poor feedstock), a very high structural stability and likely other favourable properties such as air capacity and water-holding capacity. Preliminary tests were conducted to compare biochar with other growing media and growing media additives. The growth of a miniature sunflower, pH and electrical conductivity (EC) was measured in different growing media such as biochar, perlite, clay granules, Sphagnum peat and peat mixed with biochar in the ratios 1 : 4, 1 : 1 and 4 : 1 (25, 50 and 75%, by volume). Fresh biochar has a similar EC to peat which is even lower after rinsing with water. Due to the relatively high pH of biochar, it could be added to peat instead of lime in a concentration of up to 75%. The growth of the sunflower was similar in all growing media. Only the plant weight was slightly higher of plants that grew in perlite or peat. There is a large potential for optimization such as selection of particle size and feedstock for biochar production and growing media formulations for specific plant requirements.

  7. Biochar as growing media additive and peat substitute

    NASA Astrophysics Data System (ADS)

    Steiner, C.; Harttung, T.

    2014-04-01

    Environmental concerns raised the demand for alternative growing media substituting sphagnum peat. However growing media formulations still depend on peat and alternatives are limited. Biochar is carbonized plant material and could be an appropriate additive or even substitute for sphagnum peat. Freshly produced, it is free from pathogens, has a low nutrient content (if produced from nutrient poor feedstock), a very high structural stability and likely other favourable properties such as air capacity and water holding capacity. Preliminary tests were conducted to compare biochar with other growing media and growing media additives. The growth of a miniature sunflower, pH and electrical conductivity (EC) was measured in different growing media such as biochar, perlite, clay granules, sphagnum peat and peat mixed with biochar in the ratios 1 : 4, 1 : 1 and 4 : 1 (25, 50 and 75%, by volume). Fresh biochar has a similar EC than peat which is even lower after rinsing with water. Due to the relatively high pH of biochar, it could be added to peat instead of lime in a concentration of up to 75%. The growth of the sunflower was similar in all growing media. Only the plant weight was slightly higher of plants that grew in perlite or peat. There is a large potential for optimization such as selection of particle size and feedstock for biochar production and growing media formulations for specific plant requirements.

  8. pH Lowering Ability of Sphagnum.

    ERIC Educational Resources Information Center

    Glime, Janice M.; Li, Yenhung

    1998-01-01

    States that the ecological role of Sphagnum species in peatlands is enormous. Presents a cation exchange experiment and background information on the characteristics and economic importance of Sphagnum. Contains 42 references. (DDR)

  9. The spectral properties of sphagnum canopies under varying hydrological conditions

    NASA Astrophysics Data System (ADS)

    Harris, A.; Bryant, R. G.; Baird, A. J.

    2003-04-01

    We tested the extent to which the reflectance properties (wavelengths: 0.4-2.5 μm) of Sphagnum can be used to indicate near-surface hydrological conditions in northern wetlands. We experimented on five species of Sphagnum: S. cuspidatum Hoffm, S. papillosum H. Lindb., S. capillifolium (Ehrh.) Hedw., S. magellanicum Brid., and S. pulchrum (Braithw.) Warnst.. Our experiments were performed on intact canopies of Sphagnum (including c. 7 cm of underlying litter - proto peat) unlike previous studies (e.g. Vogelmann & Moss, 1993). In drying experiments on the first three species we found species-specific associations between: (1) The ratio of short-wave infrared (SWIR: 1.3-2.5 μm) to near infrared reflectance (NIR: 0.7-1.3 μm) (SWIR/NIR) and the volumetric moisture content (VMC) of the near-surface zone of the acrotelm. (2) The relative depth of the water absorption feature at 1.205 μm (RDI) and the near-surface VMC. (3) The red edge inflection point (REIP) and near-surface VMC. In experiments involving drying followed by re-wetting on samples of S. magellanicum and S. pulchrum, we found that the relationships outlined in 1, 2 and 3 were hysteretic. We comment on the implications of our results for monitoring large-scale, intra- and inter- seasonal changes in carbon balance processes in northern wetlands.

  10. Comparison of pelletized biochar derived from two source materials as replacements for peat in potting substrates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  11. Peat Processing

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Humics, Inc. already had patented their process for separating wet peat into components and processing it when they consulted NERAC regarding possible applications. The NERAC search revealed numerous uses for humic acid extracted from peat. The product improves seed germination, stimulates root development, and improves crop yields. There are also potential applications in sewage disposal and horticultural peat, etc.

  12. Photosynthesis, growth, and decay traits in Sphagnum - a multispecies comparison.

    PubMed

    Bengtsson, Fia; Granath, Gustaf; Rydin, Håkan

    2016-05-01

    Peat mosses (Sphagnum) largely govern carbon sequestration in Northern Hemisphere peatlands. We investigated functional traits related to growth and decomposition in Sphagnum species. We tested the importance of environment and phylogeny in driving species traits and investigated trade-offs among them. We selected 15 globally important Sphagnum species, representing four sections (subgenera) and a range of peatland habitats. We measured rates of photosynthesis and decomposition in standard laboratory conditions as measures of innate growth and decay potential, and related this to realized growth, production, and decomposition in their natural habitats. In general, we found support for a trade-off between measures of growth and decomposition. However, the relationships are not strong, with r ranging between 0.24 and 0.45 for different measures of growth versus decomposition. Using photosynthetic rate to predict decomposition in standard conditions yielded R (2) = 0.20. Habitat and section (phylogeny) affected the traits and the trade-offs. In a wet year, species from sections Cuspidata and Sphagnum had the highest production, but in a dry year, differences among species, sections, and habitats evened out. Cuspidata species in general produced easily decomposable litter, but their decay in the field was hampered, probably due to near-surface anoxia in their wet habitats. In a principal components analysis, PCA, photosynthetic capacity, production, and laboratory decomposition acted in the same direction. The species were imperfectly clustered according to vegetation type and phylogeny, so that some species clustered with others in the same section, whereas others clustered more clearly with others from similar vegetation types. Our study includes a wider range of species and habitats than previous trait analyses in Sphagnum and shows that while the previously described growth-decay trade-off exists, it is far from perfect. We therefore suggest that our species

  13. Metal and proton adsorption capacities of natural and cloned Sphagnum mosses.

    PubMed

    Gonzalez, Aridane G; Pokrovsky, Oleg S; Beike, Anna K; Reski, Ralf; Di Palma, Anna; Adamo, Paola; Giordano, Simonetta; Fernandez, J Angel

    2016-01-01

    Terrestrial mosses are commonly used as bioindicators of atmospheric pollution. However, there is a lack of standardization of the biomonitoring preparation technique and the efficiency of metal adsorption by various moss species is poorly known. This is especially true for in vitro-cultivated moss clones, which are promising candidates for a standardized moss-bag technique. We studied the adsorption of copper and zinc on naturally grown Sphagnum peat moss in comparison with in vitro-cultivated Sphagnum palustre samples in order to provide their physico-chemical characterization and to test the possibility of using cloned peat mosses as bioindicators within the protocol of moss-bag technique. We demonstrate that in vitro-grown clones of S. palustre exhibit acid-base properties similar to those of naturally grown Sphagnum samples, whereas the zinc adsorption capacity of the clones is approx. twice higher than that of the samples from the field. At the same time, the field samples adsorbed 30-50% higher amount of Cu(2+) compared to that of the clones. This contrast may be related to fine differences in the bulk chemical composition, specific surface area, morphological features, type and abundance of binding sites at the cell surfaces and in the aqueous solution of natural and cloned Sphagnum. The clones exhibited much lower concentration of most metal pollutants in their tissues relative to the natural samples thus making the former better indicators of low metal loading. Overall, in vitro-produced clones of S. palustre can be considered as an adequate, environmentally benign substitution for protected natural Sphagnum sp. samples to be used in moss-bags for atmospheric monitoring. PMID:26407060

  14. Effect of Peat Moss and Pumice on Douglas Fir Bark based Soilless Substrate Physical and Hydraulic Properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  15. Effects of inorganic sulfur addition on fluxes of volatile sulfur compounds in Sphagnum peatlands

    NASA Technical Reports Server (NTRS)

    Demello, William Zamboni; Hines, Mark E.; Bayley, Suzanne E.

    1992-01-01

    Short and long-term impacts of increased S deposition on fluxes of volatile S compounds (VSC's) from Sphagnum peatlands were investigated in an artificially acidified (sulfuric and nitric acids) poor fen (Mire 239) at the Experimental Lakes Area (ELA), Ontario, Canada. Additional experiments were conducted in a poor fen (Sallie's Fen) in Barrington, NH, USA. At Mire 239, emissions of VSC's were monitored, before and after acidification, at control (unacidified) and experimental sections within two major physiographic zones of the mire (oligotrophic and minerotrophic). The experimental segments of the mire received S amendments since 1983, in amounts equivalent to the annual S deposition in the highest polluted areas of Canada and U.S. Dimethyl sulfide (DMS) was the predominant VSC released from the mire and varied largely with time and space (i.e., from 2.5 to 127 nmol/m(sup -2)h(sup -1)). Sulfur addition did not affect DMS emissions in a period of hours to a few days, although it stimulated production of DMS and MSH in the anoxic surficial regions of the peat. DMS emissions in the experimental oligotrophic segment of the mire was approximately 3-fold greater than in the control oligotrophic segment, and approximately 10-fold greater than in the minerotrophic zones. These differences could be due to a combination of differences in types of vegetation, nutritional status, and S input. At Sallie's Fen, DMS fluxes were approximately 8 times higher from a Sphagnum site than from a bare peat site. Fluxes of VSC's were not significantly affected by sulfate amendments at both sites, while DMS and MSH concentrations increases greatly with time in the top 10 cm of the peat column. Our data indicated that although Sphagnum is not the direct source of DMS released from Sphagnum peatlands, it might play a role in regulating DMS emissions to the atmosphere.

  16. How hydrology and vegetation modify microclimate of a Sphagnum peatland?

    NASA Astrophysics Data System (ADS)

    Słowińska, Sandra; Słowiński, Michał; Marcisz, Katarzyna; Lamentowicz, Łukasz; Lamentowicz, Mariusz

    2014-05-01

    Climate and hydrology are key factors influencing peat accumulation and decomposition. This, in turn have strong influence on carbon sequestration what is nowadays the central aim of peatlands ecology. However, peatlands are not homogenous ecosystems. There are often a mosaic of vegetation patterns. Differences in depth of groundwater tables are also common at one object. We designed a long-term ecological study site in a Sphagnum peatland in the Northern Poland. We used five meteorological micro-stations and eleven piezometers located along two transects at 5,95 ha area. We have focused on microclimatic and hydrological changes during two growing seasons - 2012 and 2013. Significant differences in radiation, air temperature and humidity were recorded between plots, which were mainly a result of reduction of light availability by trees in two of five plots. That also influenced on surface wetness of Sphagnum mosses. Range of groundwater table changes varied between plots but trends were similar. Further research will focus on the synthesis of relationships between climate, hydrology and vegetation. A separate work will be concentrated on testate amoebae response to wetness, temperature and light availability. Our study is very important to better understand peatland functioning in transition climate in small spatial scale. Project supported by Polish National Science Centre grant No. NN306060940 and the grant PSPB-013/2010 from Switzerland through the Swiss Contribution to the enlarged European Union.

  17. [Analysis of the bacterial community developing in the course of Sphagnum moss decomposition].

    PubMed

    Kulichevskaia, I S; Belova, S E; Kevbrin, V V; Dedysh, S N; Zavarzin, G A

    2007-01-01

    Slow degradation of organic matter in acidic Sphagnum peat bogs suggests a limited activity of organotrophic microorganisms. Monitoring of the Sphagnum debris decomposition in a laboratory simulation experiment showed that this process was accompanied by a shift in the water color to brownish due to accumulation of humic substances and by the development of a specific bacterial community with a density of 2.4 x 10(7) cells ml(-1). About half of these organisms are metabolically active and detectable with rRNA-specific oligonucleotide probes. Molecular identification of the components of this microbial community showed the numerical dominance of bacteria affiliated with the phyla Alphaproteobacteria, Actinobacteria, and Phanctomycetes. The population sizes of Firmicutes and Bacteroidetes, which are believed to be the main agents of bacterially-mediated decomposition in eutrophic wetlands, were low. The numbers of planctomycetes increased at the final stage of Sphagnum decomposition. The representative isolates of Alphaproteobacteria were able to utilize galacturonic acid, the only low-molecular-weight organic compound detected in the water samples; the representatives of Planctomycetes were able to decompose some heteropolysaccharides, which points to the possible functional role of these groups of microorganisms in the community under study. Thus, the composition of the bacterial community responsible for Sphagnum decomposition in acidic and low-mineral oligotrophic conditions seems to be fundamentally different from that of the bacterial community which decomposes plant debris in eutrophic ecosystems at neutral pH. PMID:18069332

  18. Sphagnum mosses as archives of recent and past atmospheric lead deposition in Switzerland

    NASA Astrophysics Data System (ADS)

    Weiss, Dominik; Shotyk, William; Kramers, Jan D.; Gloor, Marlies

    Sphagnum mosses received from a herbarium and collected recently from a peat bog surface, were used to assess the isotopic character of past and recent atmospheric Pb deposition in Switzerland and to constrain possible Pb sources. Lead removed from the moss surface was isotopically similar to that measured in the corresponding solid plant, suggesting that neither preservative actions for the herbarium samples nor dust had affected the isotopic composition of the samples. The addition of HCl to aqueous extracts to remove surface particles from the plants released more Pb compared to H 2O alone. The changes in isotope ratios between Sphagnum collected during the past c. 130 yr were significantly greater than the small fluctuations between and among species collected at any one time. Three isotope ratio plots and emission inventories indicated that the most likely source of atmospheric Pb was coal-burning at the turn of the century, fly ash from waste incineration until approximately 1950, and gasoline combustion after that. The pollution record derived from the Sphagnum plants is in good agreement with other archives from Switzerland (peat, sediment, ice) and with other herbarium records in Europe.

  19. Application of static and dynamic enclosures in determining DMS and OCS fluxes in Sphagnum peatlands

    NASA Technical Reports Server (NTRS)

    Demello, William Zamboni; Hines, Mark E.

    1992-01-01

    A static enclosure method was applied to determine the exchange of dimethyl sulfide (DMS) and OCS between the surface of Sphagnum peatlands and the atmosphere. Measurements were performed concurrently with dynamic enclosure measurements with S-free air used as sweep gas. DMS emission rates determined by both methods were comparable between 5 and 500 nmol/m(sup -2)h(sup -1). The dynamic method provided positive OCS flux rates (emission) for measurements performed at sites containing Sphagnum. Conversely, data from the static method indicated that OCS was consumed from the atmosphere. Measurements using both techniques at a site devoid of vegetation showed that peat is a source of both DMS and OCS. Results suggested that OCS is produced in surface peat but it is taken up from the atmosphere by Sphagnum mosses. However, the net effect of both processes is that OCS uptake exceeds emission. The dynamic enclosure technique is adequate to measure rates of emissions of S gases which are produced in peatlands but not consumed, as long as attention is paid to the rate of sweep flow.

  20. Decomposition of peat from upland boreal forest: Temperature dependence and sources of respired carbon

    NASA Astrophysics Data System (ADS)

    Dioumaeva, Irina; Trumbore, Susan; Schuur, Edward A. G.; Goulden, Michael L.; Litvak, Marcy; Hirsch, Adam I.

    2002-02-01

    The response of large stores of carbon in boreal forest soils to global warming is a major uncertainty in predicting the future carbon budget. We measured the temperature dependence of decomposition for upland boreal peat under black spruce forest with sphagnum and feather moss understory using incubation experiments. CO2 efflux rates clearly responded to temperature, which ranged from -10° to +8°C by ˜2°C increments. At temperatures below 0°C, significant decomposition was observed in feather moss peat but not in wetter sphagnum peat. Above 0°C, decomposition was exponentially related to temperature, corresponding to a Q(10) (the ratio of the rate of CO2 evolution at one temperature divided by that at a temperature 10°C cooler) of 4.4 for feather moss and 3.1 for sphagnum peat. The greatest change in CO2 evolution rate with temperature occurred between -2° and 0°C, which coincided with the phase transition of soil water. We saw no large change in the rate of CO2 evolution between incubation experiments separated by a 6 month storage period for feather moss peat. Stable C isotope measurements of evolved CO2 and the rate of change of CO2 evolution with time suggest different substrates are used to sustain heterotrophic respiration above and below freezing. Radiocarbon signatures of CO2 respired from both types of peat reflected significant contributions from C fixed in the last 35 years ("bomb" 14C) as well as C fixed prior to 1950. We observed no change in the Δ14C of respired CO2 with temperature. Isotopic signatures of peat components showed that a combination of substrates must contribute to the CO2 evolved in our incubations. Decomposition of fine roots (which made up less than 7% of the total peat C) accounted for ˜50% of respired CO2 in feather moss peat and for ˜30% of respired CO2 in sphagnum peat. Fine-grained (<1 mm), more humified material that makes up 60-70% of the bulk peat organic carbon contributed significantly to heterotrophic

  1. Decomposition of peat from upland boreal forest: Temperature dependence and sources of respired carbon

    NASA Astrophysics Data System (ADS)

    Dioumaeva, Irina; Trumbore, Susan; Schuur, Edward A. G.; Goulden, Michael L.; Litvak, Marcy; Hirsch, Adam I.

    2003-02-01

    The response of large stores of carbon in boreal forest soils to global warming is a major uncertainty in predicting the future carbon budget. We measured the temperature dependence of decomposition for upland boreal peat under black spruce forest with sphagnum and feather moss understory using incubation experiments. CO2 efflux rates clearly responded to temperature, which ranged from -10° to +8°C by ~2°C increments. At temperatures below 0°C, significant decomposition was observed in feather moss peat but not in wetter sphagnum peat. Above 0°C, decomposition was exponentially related to temperature, corresponding to a Q(10) (the ratio of the rate of CO2 evolution at one temperature divided by that at a temperature 10°C cooler) of 4.4 for feather moss and 3.1 for sphagnum peat. The greatest change in CO2 evolution rate with temperature occurred between -2° and 0°C, which coincided with the phase transition of soil water. We saw no large change in the rate of CO2 evolution between incubation experiments separated by a 6 month storage period for feather moss peat. Stable C isotope measurements of evolved CO2 and the rate of change of CO2 evolution with time suggest different substrates are used to sustain heterotrophic respiration above and below freezing. Radiocarbon signatures of CO2 respired from both types of peat reflected significant contributions from C fixed in the last 35 years (``bomb'' 14C) as well as C fixed prior to 1950. We observed no change in the Δ14C of respired CO2 with temperature. Isotopic signatures of peat components showed that a combination of substrates must contribute to the CO2 evolved in our incubations. Decomposition of fine roots (which made up less than 7% of the total peat C) accounted for ~50% of respired CO2 in feather moss peat and for ~30% of respired CO2 in sphagnum peat. Fine-grained (<1 mm), more humified material that makes up 60-70% of the bulk peat organic carbon contributed significantly to heterotrophic

  2. Wetland Expansion on the Southern Edge of the West Siberian Sphagnum Wetlands

    NASA Astrophysics Data System (ADS)

    Peregon, A.

    2006-12-01

    The southern border of Vasyugan wetland was chosen to analyse the long term trend in organic carbon (peat) accumulation and wetland expansion processes. In our study, the comprehensive field (soil/peat and geobotanical) studies were conducted and the results were extrapolated using Landsat ETM+ satellite images. Two types of interaction (ecotones) between forest and wetland were revealed within the study area. Variations in the trend of peat accumulation were found in two types of ecotones, strongly affected by topography and chemical properties of the mineral subsoil of wetland basin. One ecotone is represented by a range of forest ecosystems on flat terrain, and differs from another by the absence of reed communities. Flat topography, coupled with loamy structure and poorness of the subsoil provide conditions for the "permanent" formation of wetlands in the forest ecotone. Progression of the Sphagnum wetlands toward the adjoining deciduous forests was confirmed by existence of the residual soils, recently covered by peat sediments. Another, forest-reeds ecotone is situated on the more uneven terrain providing the path for water flow from the periphery of wetland basin. This causes the recurrence of drying and wetting of upper peat layers, resulting in the fluctuation in the carbon-storage capability of the area and recurring peat degradation on the periphery of peatland basin. The reed ecosystems are the sure indicator of carbonates located close to the land surface. The high concentration of carbonates in subsoil inhibits the advance of Sphagnum mosses and subsequent expansion of wetlands (i.e. "intermittent" wetland formation). Finally, the forest wetland boundary areas on the satellite images were classified into different types of ecotones described earlier. The final layout, prepared in the scale of 1:200K, demonstrates the evident activity of the wetland expansion processes even in the relatively dry climate without excess of precipitation over evaporation

  3. The Comparative Study of Element Accumulation in Wood Fen Peat (Latvia)

    NASA Astrophysics Data System (ADS)

    Krumins, Janis; Klavins, Maris; Kuske, Eliza; Seglins, Valdis; Kaup, Enn

    2013-04-01

    Mires belong to the most representative archives of past environmental conditions in large areas of temperate and subarctic zone. Moreover, mires keep evidence of ancient cultures and modern human activity. Consequently the research of mires is an integral part of global change studies. Fens are less studied than bogs; one of the reasons is the complexity of factors that impact peat formation. Bogs, due to dome-shaped structure, are affected by precipitation, while other external influences are negligible and simply separable. The aim of this research was the characterization of accumulation patterns of metallic elements in wood fen peat profiles and to assess their accumulation regularities in relation with peat properties. The general idea was to find out how admixtures of plant remains in different stages of decomposition change properties and the element accumulation character in a wood peat. In obtained profiles were separated five types of wood peat: wood, wood-sedge, wood-reed, wood-grass and wood- sphagnum peat. Peat was sampled in four Latvian fens: Elki, Viki, Svetupe and Sala. Similar environment, origin and development of sites suggest similar development of peat properties thus there is no reason to assume different impact on peat development among mires. Despite a slow decomposition rate, results point to a higher decomposition degree of wood peat, in comparison with other types of fen peat. In average, wood peat forms the thickest layers, but it must be taken into account that thickness depends on coating layers, presence of decomposed plant remains etc. The accumulation pattern of metallic elements in a wood fen peat slightly differs among sites, but the difference among wood peat types is clearly evident. For instance, the highest amount of iron is characteristic to wood-reed peat, while, the lowest, is in wood-sphagnum peat. At the same time, in wood-reed peat the lowest amounts of magnesium were found while the highest amount of Mg was in wood

  4. Photosynthetic traits of Sphagnum and feather moss species in undrained, drained and rewetted boreal spruce swamp forests

    PubMed Central

    Kangas, Laura; Maanavilja, Liisa; Hájek, Tomáš; Juurola, Eija; Chimner, Rodney A; Mehtätalo, Lauri; Tuittila, Eeva-Stiina

    2014-01-01

    In restored peatlands, recovery of carbon assimilation by peat-forming plants is a prerequisite for the recovery of ecosystem functioning. Restoration by rewetting may affect moss photosynthesis and respiration directly and/or through species successional turnover. To quantify the importance of the direct effects and the effects mediated by species change in boreal spruce swamp forests, we used a dual approach: (i) we measured successional changes in moss communities at 36 sites (nine undrained, nine drained, 18 rewetted) and (ii) photosynthetic properties of the dominant Sphagnum and feather mosses at nine of these sites (three undrained, three drained, three rewetted). Drainage and rewetting affected moss carbon assimilation mainly through species successional turnover. The species differed along a light-adaptation gradient, which separated shade-adapted feather mosses from Sphagnum mosses and Sphagnum girgensohnii from other Sphagna, and a productivity and moisture gradient, which separated Sphagnum riparium and Sphagnum girgensohnii from the less productive S. angustifolium, S. magellanicum and S. russowii. Undrained and drained sites harbored conservative, low-production species: hummock-Sphagna and feather mosses, respectively. Ditch creation and rewetting produced niches for species with opportunistic strategies and high carbon assimilation. The direct effects also caused higher photosynthetic productivity in ditches and in rewetted sites than in undrained and drained main sites. PMID:24634723

  5. Sphagnum Mosses - Masters of Efficient N-Uptake while Avoiding Intoxication

    PubMed Central

    Fritz, Christian; Lamers, Leon P. M.; Riaz, Muhammad; van den Berg, Leon J. L.; Elzenga, Theo J. T. M.

    2014-01-01

    Peat forming Sphagnum mosses are able to prevent the dominance of vascular plants under ombrotrophic conditions by efficiently scavenging atmospherically deposited nitrogen (N). N-uptake kinetics of these mosses are therefore expected to play a key role in differential N availability, plant competition, and carbon sequestration in Sphagnum peatlands. The interacting effects of rain N concentration and exposure time on moss N-uptake rates are, however, poorly understood. We investigated the effects of N-concentration (1, 5, 10, 50, 100, 500 µM), N-form (15N - ammonium or nitrate) and exposure time (0.5, 2, 72 h) on uptake kinetics for Sphagnum magellanicum from a pristine bog in Patagonia (Argentina) and from a Dutch bog exposed to decades of N-pollution. Uptake rates for ammonium were higher than for nitrate, and N-binding at adsorption sites was negligible. During the first 0.5 h, N-uptake followed saturation kinetics revealing a high affinity (Km 3.5–6.5 µM). Ammonium was taken up 8 times faster than nitrate, whereas over 72 hours this was only 2 times. Uptake rates decreased drastically with increasing exposure times, which implies that many short-term N-uptake experiments in literature may well have overestimated long-term uptake rates and ecosystem retention. Sphagnum from the polluted site (i.e. long-term N exposure) showed lower uptake rates than mosses from the pristine site, indicating an adaptive response. Sphagnum therefore appears to be highly efficient in using short N pulses (e.g. rainfall in pristine areas). This strategy has important ecological and evolutionary implications: at high N input rates, the risk of N-toxicity seems to be reduced by lower uptake rates of Sphagnum, at the expense of its long-term filter capacity and related competitive advantage over vascular plants. As shown by our conceptual model, interacting effects of N-deposition and climate change (changes in rainfall) will seriously alter the functioning of Sphagnum peatlands

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

    SciTech Connect

    Cohen, A.D.; Stack, E.M.; Eltayeb, S.; Durig, J.B

    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 from 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.

  7. 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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  9. Sphagnum mosses from 21 ombrotrophic bogs in the athabasca bituminous sands region show no significant atmospheric contamination of "heavy metals".

    PubMed

    Shotyk, William; Belland, Rene; Duke, John; Kempter, Heike; Krachler, Michael; Noernberg, Tommy; Pelletier, Rick; Vile, Melanie A; Wieder, Kelman; Zaccone, Claudio; Zhang, Shuangquan

    2014-11-01

    Sphagnum moss was collected from 21 ombrotrophic (rain-fed) peat bogs surrounding open pit mines and upgrading facilities of Athabasca bituminous sands in Alberta (AB). In comparison to contemporary Sphagnum moss from four bogs in rural locations of southern Germany (DE), the AB mosses yielded lower concentrations of Ag, Cd, Ni, Pb, Sb, and Tl, similar concentrations of Mo, but greater concentrations of Ba, Th, and V. Except for V, in comparison to the "cleanest", ancient peat samples ever tested from the northern hemisphere (ca. 6000-9000 years old), the concentrations of each of these metals in the AB mosses are within a factor of 3 of "natural, background" values. The concentrations of "heavy metals" in the mosses, however, are proportional to the concentration of Th (a conservative, lithophile element) and, therefore, contributed to the plants primarily in the form of mineral dust particles. Vanadium, the single most abundant trace metal in bitumen, is the only anomaly: in the AB mosses, V exceeds that of ancient peat by a factor of 6; it is therefore enriched in the mosses, relative to Th, by a factor of 2. In comparison to the surface layer of peat cores collected in recent years from across Canada, from British Columbia to New Brunswick, the Pb concentrations in the mosses from AB are far lower. PMID:25259407

  10. Factors controlling fluxes of volatile sulfur compounds in Sphagnum peatlands. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Demello, William Zamboni

    1992-01-01

    Exchange of DMS and OCS between the surface of Sphagnum peatlands and the atmosphere were measured with dynamic (S-free sweep air) and static enclosures. DMS emission rates determined by both methods were comparable. The dynamic method provided positive OCS flux rates (emission) for measurements performed at sites containing Sphagnum. Conversely, data from the static method indicated that OCS was consumed from the atmosphere. Short and long-term impacts of increased S deposition on fluxes of volatile S compounds (VSC's) from Sphagnum peatlands were investigated in a poor fen (Mire 239) at the Experimental Lakes Area, Ontario, Canada. Additional experiments were conducted in a poor fen (Sallie's Fen in Barrington, NH, USA). At Mire 239, emissions of VSC's were monitored, before and after acidification, at control and experimental sections within two major physiographic areas of the mire (oligotrophic and minerotrophic). DMS was the predominant VSC released from Mire 239 and varied largely with time and space. Sulfur addition did not affect DMS emissions in a period of hours to a few days. DMS emissions in the experimental oligotrophic area of the mire was approximately 3-fold greater than in the control oligotrophic area, and approximately 10-fold greater than in the minerotrophic zones. These differences could be due to a combination of differences in types of vegetation, nutritional status, and S input. At Sallie's Fen, DMS fluxes were not significantly affected by sulfate amendments, while DMS and MSH concentrations increased greatly with time in the top 10 cm of the peat column. The major environmental factors controlling fluxes of DMS in a Sphagnum-dominated peatland were investigated in Sallie's Fen, NH. DMS emissions from the surface of the peatland varied greatly over 24 hours and seasonally. Temperature seemed to be the major environmental factor controlling these variabilities. Concentrations of dissolved VSC's varied with time and space throughout the fen

  11. The impact of drought and air pollution on metal profiles in peat cores.

    PubMed

    Souter, Laura; Watmough, Shaun A

    2016-01-15

    Peat cores have long been used to reconstruct atmospheric metal deposition; however, debate remains regarding how well historical depositional patterns are preserved in peat. This study examined peat cores sampled from 14 peatlands in the Sudbury region of Ontario, Canada, which has a well-documented history of acid and metal deposition. Copper (Cu) and lead (Pb) concentrations within individual peat cores were strongly correlated and were elevated in the upper 10 cm, especially in the sites closest to the main Copper Cliff smelter. In contrast, nickel (Ni) and cobalt (Co) concentrations were often elevated at depths greater than 10 cm, indicating much greater post-depositional movement of these metals compared with Cu and Pb. Post-depositional movement of metals is supported by the observation that Ni and Co concentrations in peat pore water increased by approximately 530 and 960% for Ni and Co, respectively between spring and summer due to drought-induced acidification, but there was much less change in Cu concentration. Sphagnum cover and (210)Pb activity measured at 10 cm at the 14 sites significantly increased with distance from Copper Cliff, and the surface peat von Post score decreased with distance from Copper Cliff, indicating the rate of peat formation increases with distance from Sudbury presumably as a result of improved Sphagnum survival. This study shows that the ability of peat to preserve deposition histories of some metals is strongly affected by drought-induced post-depositional movement and that loss of Sphagnum due to air pollution impairs the rate of peat formation, further affecting metal profiles in peatlands. PMID:26473705

  12. 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.

  13. 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.

  14. Burned and unburned peat water repellency: Implications for peatland evaporation following wildfire

    NASA Astrophysics Data System (ADS)

    Kettridge, N.; Humphrey, R. E.; Smith, J. E.; Lukenbach, M. C.; Devito, K. J.; Petrone, R. M.; Waddington, J. M.

    2014-05-01

    Water repellency alters soil hydrology after periods of wildfire, potentially modifying the ecosystem recovery to such disturbance. Despite this potential importance, the extent and severity of water repellency within burned peatlands and its importance in regulating peatland recovery to wildfire disturbance remains poorly understood. We characterised the water repellency of peat in a burned (one year post-fire) and unburned peatland in the Western Boreal Plain utilising the water drop penetration time and ethanol droplet molarity tests. Burned Sphagnum moss and feather moss sites had a more severe degree of water repellency than unburned sites, with differences being more pronounced between burned and unburned feather moss sites. Burned feather moss exhibited the most extreme water repellency, followed by unburned feather moss, and burned Sphagnum. The severity of water repellency varied with depth through the near surface of the moss/peat profile. This was most evident within the burned feathermoss where more extreme water repellency was observed at the near-surface compared to the surface, with the most extreme water repellency found at 1 and 5 cm depths. Unburned Sphagnum was completely hydrophilic at all depths. We suggest that the extreme water repellency in near-surface feather moss peat acts as a barrier that impedes the supply of water to the surface that replaces that lost via evaporation. This leads to drying of the near-surface vadose zone within feather moss areas and a concomitantly large decrease in peatland evaporation within feather moss dominated peatlands. This negative feedback mechanism likely enhances the resilience of such peatland to wildfire disturbance, maintaining a high water table position, thereby limiting peat decomposition. In comparison, such a feedback is not observed strongly within Sphagnum, leaving Sphagnum dominated peatlands potentially vulnerable to low water table positions post disturbance.

  15. The use of plant-specific pyrolysis products as biomarkers in peat deposits

    NASA Astrophysics Data System (ADS)

    Schellekens, Judith; Bradley, Jonathan A.; Kuyper, Thomas W.; Fraga, Isabel; Pontevedra-Pombal, Xabier; Vidal-Torrado, Pablo; Abbott, Geoffrey D.; Buurman, Peter

    2015-09-01

    Peatlands are archives of environmental change that can be driven by climate and human activity. Proxies for peatland vegetation composition provide records of (local) environmental conditions that can be linked to both autogenic and allogenic factors. Analytical pyrolysis offers a molecular fingerprint of peat, and thereby a suite of environmental proxies. Here we investigate analytical pyrolysis as a method for biomarker analysis. Pyrolysates of 48 peatland plant species were compared, comprising seventeen lichens, three Sphagnum species, four non-Sphagnum mosses, eleven graminoids (Cyperaceae, Juncaceae, Poaceae), five Ericaceae and six species from other families. This resulted in twenty-one potential biomarkers, including new markers for lichens (3-methoxy-5-methylphenol) and graminoids (ferulic acid methyl ester). The potential of the identified biomarkers to reconstruct vegetation composition is discussed according to their depth records in cores from six peatlands from boreal, temperate and tropical biomes. The occurrence of markers for Sphagnum, graminoids and lichens in all six studied peat deposits indicates that they persist in peat of thousands of years old, in different vegetation types and under different conditions. In order to facilitate the quantification of biomarkers from pyrolysates, typically expressed as proportion (%) of the total quantified pyrolysis products, an internal standard (5-α-androstane) was introduced. Depth records of the Sphagnum marker 4-isopropenylphenol from the upper 3 m of a Sphagnum-dominated peat, from samples analysed with and without internal standard showed a strong positive correlation (r2 = 0.72, P < 0.0005, n = 12). This indicates that application of an internal standard is a reliable method to assess biomarker depth records, which enormously facilitates the use of analytical pyrolysis in biomarker research by avoiding quantification of a high number of products.

  16. REMOVAL OF ADDED NITRATE IN COTTON BURR COMPOST, MULCH COMPOST, AND PEAT: MECHANISMS AND POTENTIAL USE FOR GROUNDWATER NITRATE REMEDIATION

    EPA Science Inventory

    We conducted batch tests on the nature and kinetics of removal of added nitrate in cotton burr compost, mulch compost, and sphagnum peat that may be potentially used in a permeable reactive barrier (PRB) for groundwater nitrate remediation. A rigorous steam autoclaving protocol (...

  17. Analysis of ecological factors limiting the destruction of high-moor peat

    NASA Astrophysics Data System (ADS)

    Dobrovol'skaya, T. G.; Golovchenko, A. V.; Zvyagintsev, D. G.

    2014-03-01

    This review presents an analysis of literature data and original studies by the authors aimed at revealing the factors inhibiting the destruction of high-moor (oligotrophic) peat. Each of the ecological factors that prevent the decomposition of the high-moor peat by different groups of microorganisms is considered. The acid reaction, low temperatures, and lack of nutrients were found not to be the primary factors inhibiting the destruction of the peat. The limited content of oxygen in the peatbogs leads to a drastic decrease in the number of mycelial microorganisms and a reduction of the activity of hydrolytic and oxidizing enzymes. The main factor inhibiting the decomposition of sphagnum is its mechanical and chemical stability, since animals crushing sphagnum are absent in the soil, and this moss has polysaccharides of special composition. The toxicity of phenol compounds, which is manifested under the aerobic conditions, prevents the activity of all the hydrolytic enzymes. This is the main reason for the slow decomposition of sphagnum peat and the long-term preservation of the residues of bodies and food in high-moor peatlands.

  18. Carbohydrates and phenols as quantitative molecular vegetation proxies in peats

    NASA Astrophysics Data System (ADS)

    Kaiser, K.; Benner, R. H.

    2012-12-01

    Vegetation in peatlands is intricately linked to local environmental conditions and climate. Here we use chemical analyses of carbohydrates and phenols to reconstruct paleovegetation in peat cores collected from 56.8°N (SIB04), 58.4°N (SIB06), 63.8°N (G137) and 66.5°N (E113) in the Western Siberian Lowland. Lignin phenols (vanillyl and syringyl phenols) were sensitive biomarkers for vascular plant contributions and provided additional information on the relative contributions of angiosperm and gymnosperm plants. Specific neutral sugar compositions allowed identification of sphagnum mosses, sedges (Cyperaceae) and lichens. Hydroxyphenols released by CuO oxidation were useful tracers of sphagnum moss contributions. The three independent molecular proxies were calibrated with a diverse group of peat-forming plants to yield quantitative estimates (%C) of vascular plant, sphagnum moss and lichen contributions in peat core samples. Correlation analysis indicated the three molecular proxies produced fairly similar results for paleovegetation compositions, generally within the error interval of each approach (≤26%). The lignin-based method generally lead to higher estimates of vascular plant vegetation. Several significant deviations were also observed due to different reactivities of carbohydrate and phenolic polymers during peat decomposition. Rapid vegetation changes on timescales of 50-200 years were observed in the southern cores SIB04 and SIB06 over the last 2000 years. Vanillyl and syringyl phenol ratios indicated these vegetation changes were largely due to varying inputs of angiosperm and gymnosperm plants. The northern permafrost cores G137 and E113 showed a more stable development. Lichens briefly replaced sphagnum mosses and vascular plants in both of these cores. Shifts in vegetation did not correlate well with Northern hemisphere climate variability over the last 2000 years. This suggested that direct climate forcing of peatland dynamics was overridden

  19. 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. PMID:26160672

  20. Emission factors for smouldering peat megafires

    NASA Astrophysics Data System (ADS)

    Hadden, Rory; Santamaria, Simon; Pironi, Paolo; Rein, Guillermo

    2016-04-01

    Smouldering wildfires occur in large deposits of peat across the globe in boreal and temperate regions. These fires are the most persistent fires on earth and consume large quantities of biomass which can take centuries or longer to regenerate. Recently large peat fires in Indonesia have caused significant health issues across a large geographic area in south east Asia. A similar event that occurred in 1997 was estimated to have released up to 13.7Gt of carbon to the atmosphere. Globally, the carbon stored in peatlands is greater than that stored in vegetation and is similar to that stored in the atmosphere. One of the major threats to these ecosystems is smouldering megafires which can be ignited easily in peat with the resulting fire persisting for extended periods of time (often many weeks or months). Given the potential impact on global carbon balances, it is essential to have accurate estimates of carbon emitted from these fires. Is is established that the emissions from any combustion process are strongly dependent on the combustion conditions these include the temperature (energy balance), availability of oxygen and the fuel composition. Because smouldering is a persistent form of combustion, it can occur over a wide range of conditions. This necessitates an understanding of emission factors linked to the burning dynamics. To allow for controlled, repeatable burning conditions across this range of conditions, a series of laboratory scale experiments were undertaken to identify the carbon dioxide, carbon monoxide and methane flux from samples of smouldering sphagnum moss peat. This peat is used as it has been extensively studied experimentally and numerically. By using repeatable experimental conditions delivered by the FM Global Fire Propagation Apparatus, the flux of CO, CO2 and methane can be linked to the smouldering fire dynamics. Smouldering in shallow fronts is represented by burning in ambient oxygen concentration while deep fronts are simulated using

  1. Carbon dynamics in peat bogs: Insights from substrate macromolecular chemistry

    NASA Astrophysics Data System (ADS)

    Kuder, Tomasz; Kruge, Michael A.

    2001-09-01

    The macromolecular compositions of subfossil plants from boreal Sphagnum bogs and restiad bogs (New Zealand) have been studied by pyrolysis-gas chromatography/mass spectrometry to evaluate the extent of degradation in the anoxic zone (catotelm) of a peat bog. Degradation of vascular plant polysaccharides was apparent only into the upper catotelm. Sphagnum was degraded more slowly than vascular plants, but no cessation of degradation was observed. The inferred rate of degradation varied depending on type of plant, extent of aerobic, precatotelmic degradation, and mode of litter deposition (rooting versus at the surface). Environmental forcing on anaerobic carbon dynamics would potentially be largest if the hydrology was disturbed at a wet and vascular plant-rich site. Peat deposited under a dry regime would be relatively inert in anaerobic conditions. Although catotelmic degradation is usually not extensive, in some cases, if labile organic matter is retained in the aerobic phase (e.g., restiad bogs) a major fraction of peat is degraded in catotelm, potentially resulting in a delayed major export of 14C-old methane.

  2. Moisture and Climatic Forcings on Sphagnum Productivity in a Cutover Peatland

    NASA Astrophysics Data System (ADS)

    Thompson, D. K.; Waddington, J. M.

    2007-12-01

    Gross ecosystem production (GEP) was measured at a sub-boreal ombotrophic peatland (Cacouna Bog) 15 km NE of Riviere-du-Loup, Quebec, in the summers of 2005 and 2006. The Cacouna bog was extensively mined between 1940 and 1970 using the block cut method. The combination of exposed, high bulk density peat and low water table (c. 30 cm) has produced a succession vegetation community of ericaceous shrubs, invasive trees, and only c. 10% Sphagnum moss cover. Chamber-based measurements were made at three locations arranged longitudinally along a cut trench. Volumetric water content (VWC) and temperature probes at four depths, tensiometers, and a meteorological station provided high temporal resolution moisture and climatic data. June to August precipitation in 2005 was 167 mm below the 30-year mean; in 2006, the deviation was only 17 mm below normal. The cool and dry summer of 2005 depressed VWC by 10-20 %, soil water tension by 20-40 mb, and maximum GEP by 5-10 g C m-2 d-1 as compared to 2006. Instantaneous GEP did not decline during prolonged rain-free periods in August 2005 where soil tensions exceeded -100 mb, within the hypothetical range of hyaline cell drainage and reduced GEP. The response of these Sphagnum cushions points to a resilience to hydrologic stress at intermediate age (35 years since establishment) not otherwise observed in younger Sphagnum cushions less than 5 years since establishment. These findings have implications on the parameterization of sensitivity to moisture stress in bog growth models, and to management of restored and naturally regenerating peatlands.

  3. 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. PMID:20185289

  4. 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

  5. Temperature variability at Dürres Maar, Germany during the Migration Period and at High Medieval Times, inferred from stable carbon isotopes of Sphagnum cellulose

    NASA Astrophysics Data System (ADS)

    Moschen, R.; Kühl, N.; Peters, S.; Vos, H.; Lücke, A.

    2011-09-01

    This paper presents a high resolution reconstruction of local growing season temperature (GST) anomalies at Dürres Maar, Germany, spanning the last two millennia. The GST anomalies were derived from a stable carbon isotope time series of cellulose chemically extracted from Sphagnum leaves (δ13Ccellulose) separated from a kettle-hole peat deposit of several metres thickness. The temperature reconstruction is based on the Sphagnum δ13Ccellulose/temperature dependency observed in calibration studies. Reconstructed GST anomalies show considerable centennial and decadal scale variability. A cold and presumably wet phase with below-average temperature is reconstructed between the 4th and 7th century AD which is in accordance with the so called European Migration Period, marking the transition from the Late Roman Period to the Early Middle Ages. At High Medieval Times, the amplitude in the reconstructed temperature variability is most likely overestimated; nevertheless, above-average temperatures are obvious during this time span, which are followed by a temperature decrease. On the contrary, a pronounced Late Roman Climate Optimum, often described as similarly warm or even warmer as medieval times, could not be detected. The temperature signal of the Little Ice Age (LIA) is not preserved in Dürres Maar due to considerable peat cutting that takes place in the first half of the 19th century. The local GST anomalies show a remarkable agreement to northern hemispheric temperature reconstructions based on tree-ring datasets and are also in accordance with climate reconstructions on the basis of lake sediments, glacier advances and retreats, and historical datasets. Most notably, e.g., during the Early Middle Ages and at High Medieval Times, temperatures were neither low nor high in general. Rather high frequency temperature variability with multiple narrow intervals of below- and above-average temperatures at maximum lasting a few decades are reconstructed. Especially the

  6. Temperature variability at Dürres Maar, Germany during the migration period and at high medieval times, inferred from stable carbon isotopes of Sphagnum cellulose

    NASA Astrophysics Data System (ADS)

    Moschen, R.; Kühl, N.; Peters, S.; Vos, H.; Lücke, A.

    2011-02-01

    This paper presents a high resolution reconstruction of local growing season temperature (GST) anomalies at Dürres Maar, Germany, spanning the last two millennia. The GST anomalies were derived from a stable carbon isotope time series of cellulose chemically extracted from Sphagnum leaves (δ13Ccellulose) separated from a kettle-hole peat deposit of several metres thickness. The temperature reconstruction is based on the Sphagnum δ13Ccellulose /temperature dependency observed in calibration studies. Reconstructed GST anomalies show considerable centennial and decadal scale variability. A cold and presumably also wet phase with below-average temperature is reconstructed between the 4th and 7th century AD which is in accordance with the so called European Migration Period marking the transition from the Late Roman Period to the Early Middle Ages. At High Medieval Times above-average temperatures are obvious followed by a temperature decrease. On the contrary, a pronounced Late Roman Climate Optimum, often described as similar warm or even warmer as medieval times, could not be detected. The temperature signal of the Little Ice Age (LIA) is not preserved in Dürres Maar due to considerable peat cutting that takes place in the first half of the 19th century. The local GST anomalies show a remarkable agreement to northern hemispheric temperature reconstructions based on tree-ring data sets and are also in accordance with climate reconstructions on the basis of lake sediments, glacier advances and retreats, and historical data sets. Most notably, e.g. during the Early Middle Ages and at High Medieval Times, temperatures were not low or high in general. Rather high frequency temperature variability with multiple narrow intervals of below- and above-average temperatures at maximum lasting a few decades are reconstructed. Especially the agreements between our estimated GST anomalies and the NH temperature reconstructions derived from tree-ring chronologies indicate the

  7. Sphagnum-dominated bog systems are highly effective yet variable sources of bio-available iron to marine waters.

    PubMed

    Krachler, Regina; Krachler, Rudolf F; Wallner, Gabriele; Steier, Peter; El Abiead, Yasin; Wiesinger, Hubert; Jirsa, Franz; Keppler, Bernhard K

    2016-06-15

    Iron is a micronutrient of particular interest as low levels of iron limit primary production of phytoplankton and carbon fluxes in extended regions of the world's oceans. Sphagnum-peatland runoff is extraordinarily rich in dissolved humic-bound iron. Given that several of the world's largest wetlands are Sphagnum-dominated peatlands, this ecosystem type may serve as one of the major sources of iron to the ocean. Here, we studied five near-coastal creeks in North Scotland using freshwater/seawater mixing experiments of natural creek water and synthetic seawater based on a (59)Fe radiotracer technique combined with isotopic characterization of dissolved organic carbon by Accelerator Mass Spectrometry. Three of the creeks meander through healthy Sphagnum-dominated peat bogs and the two others through modified peatlands which have been subject to artificial drainage for centuries. The results revealed that, at the time of sampling (August 16-24, 2014), the creeks that run through modified peatlands delivered 11-15μg iron per liter creek water to seawater, whereas the creeks that run through intact peatlands delivered 350-470μg iron per liter creek water to seawater. To find out whether this humic-bound iron is bio-available to marine algae, we performed algal growth tests using the unicellular flagellated marine prymnesiophyte Diacronema lutheri and the unicellular marine green alga Chlorella salina, respectively. In both cases, the riverine humic material provided a highly bio-available source of iron to the marine algae. These results add a new item to the list of ecosystem services of Sphagnum-peatlands. PMID:26971209

  8. Inorganic contents of peats

    SciTech Connect

    Raymond, R. Jr.; Bish, D.L.; Cohen, A.D.

    1988-02-01

    Peat, the precursor of coal, is composed primarily of plant components and secondarily of inorganic matter derived from a variety of sources. The elemental, mineralogic, and petrographic composition of a peat is controlled by a combination of both its botanical and depositional environment. Inorganic contents of peats can vary greatly between geographically separated peat bogs as well as vertially and horizontally within an individual bog. Predicting the form and distribution of inorganic matter in a coal deposit requires understanding the distribution and preservation of inorganic matter in peat-forming environments and diagenetic alterations affecting such material during late-stage peatification and coalification processes. 43 refs., 4 figs., 3 tabs.

  9. Long-Term Perspectives of Shrub Expansions and Peat Initiation in Arctic Tundra on the North Slope of Alaska

    NASA Astrophysics Data System (ADS)

    Cleary, K.; Yu, Z.

    2014-12-01

    The ongoing climate warming in the Arctic has caused rapid terrestrial ecosystem changes, including shrub expansion and permafrost thaw. Here we used results from a peat-accumulating permafrost tundra in upper Imnavait Creek on the Arctic foothills of Alaska (68° 36' N, 149° 18' W) to investigate ecological responses to recent climate warming in the context of the last millennium. Six peat soil cores were collected from Sphagnum mosaics along an elevational gradient from 906 m to 950 m on a hillslope covered by Eriophorum-dominated tussock tundra. Macrofossil analysis documents a consistent development sequence among all cores from a mineral soil to a minerotrophic sedge peat and finally to an ombrotrophic Sphagnum peat. The 14C dating results show the ages of peat initiation range from about 900 to 140 cal BP, but do not follow the elevation gradient, suggesting the dominant control of local factors. The Sphagnum onset begins at 1820 AD near the ridge top, and subsequently propagates downslope to the floodplain at 2008 AD. This transition (ombrotrophication) was likely in response to Arctic warming, and subsequent permafrost thaw and active layer thickening, leading to drying initiating at the ridge top and facilitating Sphagnum colonization. Pollen analysis of the master core UIC13-3 at 916 m elevation (basal age 700 cal BP) shows that the vegetation was dominated by sedges (up to 84%) during the cool Little Ice Age until 1800 AD, followed by increases in shrubs first from dwarf birch (Betula nana) (up to 57%) and then willows (Salix spp.) up to 62% in the 1960s. These results indicate that shrub expansion of willows, due to accelerated warming in recent decades, was preceded by birch expansion over the last two centuries. Our new results provide a long-term perspective on ecological transformations in the Arctic, in particular the history of recent shrub expansions and the process of peatland initiation and expansion across Arctic tundra.

  10. Peat properties and water retention in boreal forested peatlands subject to wildfire

    NASA Astrophysics Data System (ADS)

    Thompson, Dan K.; Waddington, James M.

    2013-06-01

    Peat cores from a recently burned peatland and one over 75 years since fire in Alberta, Canada were analyzed for physical properties and water retention. Wildfire exposed denser peat at the peat surface, more so in hollow than hummock microforms. Water retention in peat has implications for postfire Sphagnum regeneration, as this more dense peat requires smaller volumes of water loss before a critical growth-inhibiting pore-water pressure of -100 mb is reached. Simulations of water retention after fire showed that hollow microforms are at a higher risk of losing low-density surface peat, which moderates water table (WT) declines via high specific yield. Exposure of dense peat to the surface after fire increases surface moisture under a constant WT. The net effect of decreasing specific yield and increasing water retention at the surface has implications on hydrologic stability and resilience of boreal peatlands to future wildfire risk under a changing climate. Earth system models incorporating wildfire disturbance in boreal peatlands would benefit from the inclusion of these hydrological feedbacks in this globally significant carbon reservoir.

  11. PEAT: an energy alternative

    SciTech Connect

    Schora, F.C.; Punwani, D.V.

    1980-01-01

    Even though peat is a low-heating value and low-bulk density fossil fuel which in its natural state contains over 80 percent moisture, it can be an economical alternative to coal, and fuel oil, as is the case in Iceland and Finland for direct combustion applications. This is because of the relative ease with which peat can be harvested, and the generally low sulfur and ash content of peat. Recent studies show that peat also has very favorable characteristics for conversion to synthetic fuels. Tests show that on the basis of chemistry and kinetics, peat is a better raw material than coal for production of synthetic fuels. Recent estimates also show that conversion of peat to high-Btu gas (>950 Btu/scf) is competitive with other alternatives of synthetic high-Btu gas. Therefore, peat can be an economical energy alternative depending upon location of peat deposits, region of energy need, scale of operation and cost of other energy alternatives.

  12. Tree invasion effects on peat water storage capacity (La Guette peatland, France)

    NASA Astrophysics Data System (ADS)

    Binet, Stephane; Viel, Emelie; Gogo, Sebastien; Le Moing, Franck; Laggoun-Defarge, Fatima

    2015-04-01

    In peatlands, carbon fluxes are mainly controlled by peat water saturation state, and this saturation state is an equilibrium between recharge/drainage fluxes and the peat storage capacity. The invasion of Sphagnum peatlands by vascular plants is a current problem in many peat-accumulating systems, raising the question of the relationships between vegetation changes and water storage capacity of peat horizons. To investigate this question, the water storage capacity of the "La Guette" peatland (France), invaded by Betula spp was monitored at the watershed scale since 2008 using a water balance approach and was estimated during the 20th century using historical photographs showing the drainage network and the land cover change. During this period, the site clearly experienced a vegetation change as the site was treeless in 1944. Two main results arise from this experimental device: (1) In this disturbed peatland, tree consumption amplifies the summer drought and the resulting water table drawdown allows an increase of air entrapment in the peat. Even if runoff flows occurred after this drought, the water storage capacity is affected, with about 30% of air that remains trapped in the peat porosity 6 months after the drought period. The effects of a single drought on peat water storage capacity are observed over more than a single hydrological cycle, suggesting a possible cumulative effect of droughts decreasing the peat water storage capacity. (2) Tree invasion is found to drive the drainage network morphology. Hydrological model calibrated for the study site suggested that the development of drainage network had reduced the water storage capacity of the peatland. These observations evidenced a positive feedback between vegetation dynamics and water storage capacity: tree invasion changes the drainage network geometry that decreases the peat water storage capacity, which in return may favor tree development. These two results highlight that the peat water storage

  13. Sensitivity of blanket peat vegetation and hydrochemistry to local disturbances.

    PubMed

    Robroek, Bjorn J M; Smart, Richard P; Holden, Joseph

    2010-10-01

    At the ecosystem scale, peatlands can be extremely resilient to perturbations. Yet, they are very sensitive to local disturbances, especially mechanical perturbations (e.g. trampling). The effects of these disturbances on vegetation, and potential effects on hydrochemical conditions along the peat surface, however, are largely unknown. We used three research tracks (paths researchers use to access their study sites) differing in time of abandonment to investigate the impact of local disturbance (trampling) on the vegetation and its short-term (< or = 2 year) recovery in a flagship research blanket peatland. Additionally, we examined the effects of local disturbance on fluvial runoff events and the concentrations of dissolved organic carbon (DOC) and particulate organic carbon (POC) in runoff water. Local disturbance heavily impacted peat vegetation, resulting in large areas of scarred and churned peat. Recovery of vascular plants along abandoned tracks was slow, but a functional Sphagnum layer re-established after just one year. The absence of vegetation elicited an increase in the number of runoff events along the tracks, by which POC runoff from the tracks increased. POC concentrations were highest in the surface water from the recently abandoned track, while they were low in the runoff water from the track abandoned longest and the undisturbed control track. We attribute this to the relatively fast recovery of the Sphagnum vegetation. DOC concentrations did not differ significantly either spatially or temporally in surface runoff or soil solution waters. While at an ecosystem scale local disturbances may be negligible in terms of carbon loss, our data points to the need for further research on the potential long-term effects of local disturbance on the vegetation, and significant effects on local scale carbon fluxes. Moreover, the effects of disturbances could be long-lasting and their role on ecosystem processes should not be underestimated. PMID:20692016

  14. Phylogenetic or environmental control on the organo-chemical composition of Sphagnum mosses?

    NASA Astrophysics Data System (ADS)

    Limpens, Juul; Nilsson, Mats

    2014-05-01

    Decomposition of organic material is one of the key processes that determines the size of the soil-feedback to global warming, but it is also a process surrounded with one of the largest uncertainties, making understanding its mechanistic drivers of crucial importance. In organic soils decomposition is closely determined by the organo-chemical composition of the litter entering the soil. But what, in turn drives the organo-chemical composition? Is it an emergent feature of the environment the species producing the litter grow in, or is it an evolutionary trait that can be tracked through the species' phylogeny? We set out to answer this question for one of the most import peat-forming plants on earth: the genus Sphagnum. We sampled 18 Sphagnum species, about equally distributed over 6 sites spanning a wide range of environmental conditions: most species were collected at multiple sites. For all species we characterised the chemical composition, focussing on three functional chemistry groups: (i) mineral elements, (ii) carbohydrate polymers (iii) non-carbohydrate polymers (aromatic and aliphatic compounds) . For each group of compounds we used multivariate statistical techniques to derive the degree of variation explained by environment: (site, position within site) and phylogeny (sections within genus Sphagnum). We found that the variation in mineral element concentrations was mostly explained by environment, with the biggest differences in the concentrations of basic cat-ions calcium and magnesium. In contrast, the variation in carbohydrates was mostly explained by phylogeny, with clear associations between sections and monosaccharides. The monosaccharide rhamnose was associated with species from the Acutifolia section known for their poor degradability, whereas xylose and galactose were closely associated with degradable species from the Cuspidata section. The composition non-carbohydrate polymers took an intermediate position: both environment and phylogeny

  15. Atmospheric Mercury Transfer to Peat Bogs Dominated by Gaseous Elemental Mercury Dry Deposition.

    PubMed

    Enrico, Maxime; Roux, Gaël Le; Marusczak, Nicolas; Heimbürger, Lars-Eric; Claustres, Adrien; Fu, Xuewu; Sun, Ruoyu; Sonke, Jeroen E

    2016-03-01

    Gaseous elemental mercury (GEM) is the dominant form of mercury in the atmosphere. Its conversion into oxidized gaseous and particulate forms is thought to drive atmospheric mercury wet deposition to terrestrial and aquatic ecosystems, where it can be subsequently transformed into toxic methylmercury. The contribution of mercury dry deposition is however largely unconstrained. Here we examine mercury mass balance and mercury stable isotope composition in a peat bog ecosystem. We find that isotope signatures of living sphagnum moss (Δ(199)Hg = -0.11 ± 0.09‰, Δ(200)Hg = 0.03 ± 0.02‰, 1σ) and recently accumulated peat (Δ(199)Hg = -0.22 ± 0.06‰, Δ(200)Hg = 0.00 ± 0.04‰, 1σ) are characteristic of GEM (Δ(199)Hg = -0.17 ± 0.07‰, Δ(200)Hg = -0.05 ± 0.02‰, 1σ), and differs from wet deposition (Δ(199)Hg = 0.73 ± 0.15‰, Δ(200)Hg = 0.21 ± 0.04‰, 1σ). Sphagnum covered during three years by transparent and opaque surfaces, which eliminate wet deposition, continue to accumulate Hg. Sphagnum Hg isotope signatures indicate accumulation to take place by GEM dry deposition, and indicate little photochemical re-emission. We estimate that atmospheric mercury deposition to the peat bog surface is dominated by GEM dry deposition (79%) rather than wet deposition (21%). Consequently, peat deposits are potential records of past atmospheric GEM concentrations and isotopic composition. PMID:26849121

  16. Chlorinated hydrocarbons in peat

    SciTech Connect

    Rapaport, R.A.

    1985-01-01

    Concentrations (ng/g), accumulation rates (ug/m/sup 2/=yr) and burdens were determined for DDT (1,1,1-trichlorophenyl2-2'bis(p-chlorophenyl)ethane), polychlorinated biphenyls. Toxaphene, hexachlorobenzene (HCB) and a,b,g-hexachlorocyclohexanes (HCHs) in peat cores taken across the mid-latitudes of North America. Because peat bogs are ombrotrophic, thereby receiving all contaminant inputs from the atmosphere and because peat cores were dated, atmospheric input functions were constructed for all of the compounds listed above excepting the HCHs. Compound inventories (burdens) in peat cores of PCBs, HCB, HCHs, Toxaphene, DDT, Pb and Zn were compared, indicating a strong influence from areas proximate to industrial sources and the atmospheric transport from source regions. Untransformed parent DDT (p,p' and o,p'-DDT) in surface peat and in precipitation provides evidence for the long range transport of DDT from neighboring countries where use has increased over the past 10-15 years. Present accumulation rates of DDT in peat are about 10-20% of maximum levels associated with peak use in the US around 1960. The DDT input function that was developed can be used to date peat cores. Transformations of DDT and PCBs were also examined in peat cores. First order transformation rates of DDT (p,p' and o,p') to DDD in anaerobic peat core environments ranged from 0.03 to 0.09 yr/sup -1/ with differences related to temperature. Aerobic transformation of PCB congeners in peat cores and microcosms was rapid for 2,3 and several 4 chlorinated congeners (T/sub 1/2 less than or equal to 0.2 to 3 years) and declined with increasing chlorine number.

  17. Investigating carbon dynamics in Siberian peat bogs using molecular-level analyses

    NASA Astrophysics Data System (ADS)

    Kaiser, K.; Benner, R. H.

    2013-12-01

    Total hydrolysable carbohydrates, and lignin and cutin acid compounds were analyzed in peat cores collected 56.8 N (SIB04), 58.4 N (SIB06), 63.8 N (G137) and 66.5 N (E113) in the Western Siberian Lowland to investigate vegetation, chemical compositions and the stage of decomposition. Sphagnum mosses dominated peatland vegetation in all four cores. High-resolution molecular analyses revealed rapid vegetation changes on timescales of 50-200 years in the southern cores Sib4 and Sib6. Syringyl and vanillyl (S/V) ratios and cutin acids indicated these vegetation changes were due to varying inputs of angiosperm and gymnosperm and root material. In the G137 and E113 cores lichens briefly replaced sphagnum mosses and vascular plants. Molecular decomposition indicators used in this study tracked the decomposition of different organic constituents of peat organic matter. The carbohydrate decomposition index was sensitive to the polysaccharide component of all peat-forming plants, whereas acid/aldehyde ratios of S and V phenols (Ac/AlS,V) followed the lignin component of vascular plants. Low carbohydrate decomposition indices in peat layers corresponded well with elevated (Ad/Al)S,V ratios. This suggested both classes of biochemicals were simultaneously decomposed, and decomposition processes were associated with extensive total mass loss in these ombrotrophic systems. Selective decomposition or transformation of lignin was observed in the permafrost-influenced northern cores G137 and E113. Both cores exhibited the highest (Ad/Al)S,V ratios, almost four-fold higher than measured in peat-forming plants. The extent of decomposition in the four peat cores did not uniformly increase with age, but showed episodic extensive decomposition events. Variable decomposition events independent of climatic conditions and vegetation shifts highlight the complexity of peatland dynamics.

  18. Dynamics of Viral Abundance and Diversity in a Sphagnum-Dominated Peatland: Temporal Fluctuations Prevail Over Habitat

    PubMed Central

    Ballaud, Flore; Dufresne, Alexis; Francez, André-Jean; Colombet, Jonathan; Sime-Ngando, Télesphore; Quaiser, Achim

    2016-01-01

    Viruses impact microbial activity and carbon cycling in various environments, but their diversity and ecological importance in Sphagnum-peatlands are unknown. Abundances of viral particles and prokaryotes were monitored bi-monthly at a fen and a bog at two different layers of the peat surface. Viral particle abundance ranged from 1.7 x 106 to 5.6 x 108 particles mL-1, and did not differ between fen and bog but showed seasonal fluctuations. These fluctuations were positively correlated with prokaryote abundance and dissolved organic carbon, and negatively correlated with water-table height and dissolved oxygen. Using shotgun metagenomics we observed a shift in viral diversity between winter/spring and summer/autumn, indicating a seasonal succession of viral communities, mainly driven by weather-related environmental changes. Based on the seasonal asynchrony between viral and microbial diversity, we hypothesize a seasonal shift in the active microbial communities associated with a shift from lysogenic to lytic lifestyles. Our results suggest that temporal variations of environmental conditions rather than current habitat differences control the dynamics of virus-host interactions in Sphagnum-dominated peatlands. PMID:26779149

  19. Dynamics of Viral Abundance and Diversity in a Sphagnum-Dominated Peatland: Temporal Fluctuations Prevail Over Habitat.

    PubMed

    Ballaud, Flore; Dufresne, Alexis; Francez, André-Jean; Colombet, Jonathan; Sime-Ngando, Télesphore; Quaiser, Achim

    2015-01-01

    Viruses impact microbial activity and carbon cycling in various environments, but their diversity and ecological importance in Sphagnum-peatlands are unknown. Abundances of viral particles and prokaryotes were monitored bi-monthly at a fen and a bog at two different layers of the peat surface. Viral particle abundance ranged from 1.7 x 10(6) to 5.6 x 10(8) particles mL(-1), and did not differ between fen and bog but showed seasonal fluctuations. These fluctuations were positively correlated with prokaryote abundance and dissolved organic carbon, and negatively correlated with water-table height and dissolved oxygen. Using shotgun metagenomics we observed a shift in viral diversity between winter/spring and summer/autumn, indicating a seasonal succession of viral communities, mainly driven by weather-related environmental changes. Based on the seasonal asynchrony between viral and microbial diversity, we hypothesize a seasonal shift in the active microbial communities associated with a shift from lysogenic to lytic lifestyles. Our results suggest that temporal variations of environmental conditions rather than current habitat differences control the dynamics of virus-host interactions in Sphagnum-dominated peatlands. PMID:26779149

  20. Bringing back the rare - biogeochemical constraints of peat moss establishment in restored cut-over bogs

    NASA Astrophysics Data System (ADS)

    Raabe, Peter; Blodau, Christian; Hölzel, Norbert; Kleinebecker, Till; Knorr, Klaus-Holger

    2016-04-01

    In rewetted cut-over bogs in north-western Germany and elsewhere almost no spontaneous recolonization of hummock peat mosses, such as Sphagnum magellanicum, S. papillosum or S. rubellum can be observed. However, to reach goals of climate protection every restoration of formerly mined peatlands should aim to enable the re-establishment of these rare but functionally important plant species. Besides aspects of biodiversity, peatlands dominated by mosses can be expected to emit less methane compared to sites dominated by graminoids. To assess the hydrological and biogeochemical factors constraining the successful establishment of hummock Sphagnum mosses we conducted a field experiment by actively transferring hummock species into six existing restoration sites in the Vechtaer Moor, a large peatland complex with active peat harvesting and parallel restoration efforts. The mosses were transferred as intact sods in triplicate at the beginning of June 2016. Six weeks (mid-July) and 18 weeks later (beginning of October) pore water was sampled in two depths (5 and 20 cm) directly beneath the inoculated Sphagnum sods as well as in untreated control plots and analysed for phosphate, ferrous iron, ammonia, nitrate and total organic carbon (TOC). On the same occasions and additionally in December, the vitality of mosses was estimated. Furthermore, the increment of moss height between July and December was measured by using cranked wires and peat cores were taken for lab analyses of nutrients and major element inventories at the depths of pore water sampling. Preliminary results indicate that vitality of mosses during the period of summer water level draw down was strongly negatively related to plant available phosphate in deeper layers of the residual peat. Furthermore, increment of moss height was strongly negatively related to TOC in the upper pore waters sampled in October. Concentration of ferrous iron in deeper pore waters was in general significantly higher beneath

  1. Behavior of lead in pristine and urbanized acid wetlands in the New Jersey pinelands with special reference to the role of Sphagnum moss

    SciTech Connect

    Vedagiri, U.K.

    1989-01-01

    The purpose of this study was to investigate the behavior of lead in naturally acidic Sphagnum moss-dominated wetlands of the New Jersey Pinelands and to compare it to the behavior of lead in similar wetlands which had been impacted by storm-water runoff. Data from the field showed that the runoff-impacted sites were characterized by elevated pH, elimination of Spaghnum ground cover, erosion of peat substrate and high lead accumulations, contributing to an effective but decreasing sink capacity. Laboratory experiments explored differences in fractionation, mobility and bioavailability of lead between the two systems. The low pH and high dissolved organic matter of the pristine waters led to higher solubilization and complexing of added lead compared to impacted waters. Lead added to runoff showed unexpectedly high solubility and lability, possibly due to low suspended solids. Lead added to runoff was also much more mobile vertically through peat columns than lead added to swampwater, possibly due to its high lability. The extremely high porosity of the peat substrate allows rapid vertical migration of solutes during events of sudden influx, such as storms. Sphagnum moss greatly decreased vertical transport by binding and flow retardation. The lead that is held in the moss layer was differentially available to different species. Red maple seedlings were better able to take up lead from the peat substrate in the absence of moss cover while cranberry plants showed the reverse pattern. This may be related to differences in rooting requirements and growth of the two species. Lead added in runoff was initially less available to the plants than in swampwater, but was ultimately taken up the red maple, which could tolerate conditions in the impacted substrates.

  2. Metal accumulation capacity of five species of Sphagnum moss

    SciTech Connect

    Aulio, K.

    1985-10-01

    The present paper describes the first experimental evidence of the species-specific differences in the cation accumulation properties in Sphagnum mosses. Manganese was chosen for the object of the experiments because this element appears to show the greatest variability under natural conditions.

  3. Elevated Nitrogen Deposition from Alberta Oil Sands Development Stimulates Phosphatase Activity in Dominant Sphagnum Moss Species

    NASA Astrophysics Data System (ADS)

    Kashi, N. N.; Wieder, R.; Vile, M. A.

    2013-12-01

    Emissions of NOx associated with Alberta oil sands (AOS) development are leading to locally elevated atmospheric N deposition, in a region where background N deposition has been historically quite low (< 1 kg/ha/yr). This elevated N deposition has the potential to alter the ecosystem structure and function of nutrient-poor boreal peatlands. Nitrogen enrichment may alter soil microbial activity, which could be manifested in changes in extracellular enzyme activities. Since 2011, we have been experimentally adding N as NH4NO3 in simulated precipitation at 0, 5, 10, 15, 20, and 25 kg N ha/yr/ plus no-water controls to a boreal bog and a poor fen (3 replicate plots per treatment). In 2013, acid phosphatase activities in living plant capitulum of Sphagnum angustifolium, Sphagnum fuscum, and Sphagnum magellanicum were quantified in June and July using 4-methyumbelliferylphosphate and fluorescence detection of the enzymatically released methylumbelliferone (MUF). Phosphatase activities did not differ with N treatment for S. angustifolium in the bog (p=0.3409) or the poor fen (p=0.0629), or for S. fuscum in the bog (p=0.1950), averaging 35.0 × 0.7, 61.6 × 1.2, and 41.6 × 0.9 μmol MUF/g DWT/hr, respectively. For S. fuscum in the poor fen, phosphatase activities differed between N treatments (p=0.0275), ranging 40.6 × 1.1 μmol MUF/g DWT/hr in the control plots to 73.7 × 2.0 μmol MUF/g DWT/hr in the 5 kg/ha/yr N treatment plots; increasing N deposition did not result in a gradual change in enzyme activity. On the other hand, S. magellanicum phosphatase activities differed between N treatments (p=0.0189) and showed a pattern of generally increasing activity with increasing N deposition (37.4 × 0.5 μmol MUF/g DWT/hr in control plots; 97.9 × 4.5 μmol MUF/g DWT/hr in the 25 kg/ha/yr N treatment plots). The differing phosphatase responses between these dominant Sphagnum species suggest unique differences in nutrient balance and/or microbial activity. Combining the

  4. Historical trends in the lead isotopic composition of archival Sphagnum mosses from Scotland (1838-2000).

    PubMed

    Farmer, John G; Eades, Lorna J; Atkins, Hannah; Chamberlain, David F

    2002-01-15

    The analysis of almost 200 Scottish Sphagnum moss samples collected over the past 170 years has revealed trends in the isotopic composition of lead similar to those previously established for dated Scottish lake sediments and peat bogs, lending credibility to these proxy records of atmospheric lead contamination and deposition. The effect of temporal variations in contributions from sources such as smelting of indigenous lead ores (206Pb/207Pb approximately 1.16-1.18), coal combustion (206Pb/207Pb approximately 1.17-1.19), and the use of imported Australian lead (206Pb/207Pb approximately 1.04) was clearly seen in the Scottish moss 206Pb/207Pb record. This showed some differences from the corresponding archival herbage record for the south of England, where the initial influence of Australian lead occurred earlier, at the end of the 19th century. A significant decline from a 206Pb/ 207Pb value of approximately 1.17 in the Scottish moss record began in the 1920s and continued until the 1980s (206Pb/207Pb approximately 1.12). The success of measures to reduce lead emissions to the atmosphere over the past 20 years in the U.K., in particular from petrol-engined vehicles using alkyl lead additives manufactured primarily from Australian lead, is evident in both the increasing 206Pb/207Pb ratio and falling lead concentration data for Scottish moss. PMID:11827048

  5. Changes in Peat Humification due to Permafrost Thaw and Plant Succession

    NASA Astrophysics Data System (ADS)

    Hodgkins, S. B.; Chanton, J.; Tfaily, M. M.; Wilson, R.; Crill, P. M.; Saleska, S. R.; Rich, V. I.; Cooper, W. T.

    2015-12-01

    The potential release of carbon from thawing permafrost peatlands is a major global change uncertainty. In addition to releasing old carbon from permafrost, thaw can also induce changes in hydrology that affect the aboveground plant community, leading to changes in litter quality and organic matter degradability. Stordalen Mire is a peat plateau in northern Sweden where permafrost thaw has led to land subsidence and inundation, causing dry palsas with intact permafrost to be replaced by Sphagnum-dominated bogs followed by sedge-dominated fens. In this study, we examined trends in solid phase peat humification along this permafrost thaw succession using a combination of C/N ratios and Fourier transform infrared (FTIR) spectroscopy. C/N ratios decreased with depth in all sites except fens, likely due to N immobilization during decomposition. In fens, depth trends in C/N ratios were complicated by the presence of Sphagnum-derived peat at depth. However, %N (by weight) at all sites was positively correlated with peat humification indices (HI), which indicate the degree of decomposition and are defined based on FTIR spectra as the ratios of absorbance at wavenumbers 1515, 1630, 2850, and 2920 cm-1 (aromatics and aliphatics) to the absorbance at 1030 cm-1 (polysaccharides). Each of these HI was inversely related to the prevalence of the carboxylic acid peak at 1720 cm-1, and this trend became weaker along the permafrost thaw gradient. This result suggests that decomposition at the early thaw stages is inhibited by organic acids, but this effect becomes less significant as thaw-induced plant succession leads to lower acidity. All of these trends in HI were strongest for the HI defined at 1630 and 1515 cm-1 (representing aromatics), indicating that peat humification at Stordalen is primarily characterized by relative increases in aromatic compounds compared to carbohydrates, with less pronounced relative increases in lipids and other aliphatics (2850 and 2920 cm-1).

  6. Third technical contractors' conference on peat

    SciTech Connect

    Not Available

    1981-01-01

    The conference dealt with the estimation of US peat reserves, methods for the gasification of peat, including biogasification, techniques for dewatering peat, and the harvesting of peat. Separate abstracts were prepared for the individual papers. (CKK)

  7. Fourth technical contractors' conference on peat

    SciTech Connect

    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)

  8. Net ecosystem CO2 exchange and evapotranspiration of a sphagnum mire: field measurements and model simulations

    NASA Astrophysics Data System (ADS)

    Olchev, Alexander; Volkova, Elena; Karataeva, Tatiana; Zatsarinnaya, Dina; Novenko, Elena

    2014-05-01

    The spatial and temporal variability of net ecosystem exchange of CO2 (NEE) and evapotranspiration (ET) of a karst-hole sphagnum peat mire situated at the boundary between broad-leaved and forest-steppe zones in the central part of European Russia (54.06N, 37.59E, 260 m a.s.l.) was described using results of field measurements and simulations with Mixfor-3D model. The area of the mire is about 1.2 ha and it is surrounded by a broadleaved forest stand. It is a typical peat mire according to water and mineral supply as well as to vegetation composition. The vegetation of the peripheral parts of the mire is typical eutrophic whereas the vegetation in its central part is represented by meso-oligothrophic plant communities. To describe the spatial variability of NEE and ET within the mire a portable measuring system consisting of a transparent ventilated chamber combined with an infrared CO2 and H2O analyzer LI-840A (Li-Cor, USA) was used. The measurements were provided along a transect from the southern peripheral part of the mire to its center under sunny clear-sky weather conditions in the period from May to September of 2012 and from May 2013 to October 2013. The chamber method was used for measurements of NEE and ET fluxes because of small size of the mire, a very uniform surrounding forest stand and the mosaic mire vegetation. All these factors promote very heterogeneous exchange conditions within the mire and make it difficult to apply, for example, an eddy covariance method that is widely used for flux measurements in the field. The results of the field measurements showed a significant spatial and temporal variability of NEE and ET that was mainly influenced by incoming solar radiation, air temperature and ground water level. During the entire growing season the central part of the mire was a sink of CO2 for the atmosphere (up to 6.8±4.2 µmol m-2 s-1 in June) whereas its peripheral part, due to strong shading by the surrounding forest, was mainly a source of

  9. Simulated climate change impact on summer dissolved organic carbon release from peat and surface vegetation: implications for drinking water treatment.

    PubMed

    Ritson, Jonathan P; Bell, Michael; Graham, Nigel J D; Templeton, Michael R; Brazier, Richard E; Verhoef, Anne; Freeman, Chris; Clark, Joanna M

    2014-12-15

    Uncertainty regarding changes in dissolved organic carbon (DOC) quantity and quality has created interest in managing peatlands for their ecosystem services such as drinking water provision. The evidence base for such interventions is, however, sometimes contradictory. We performed a laboratory climate manipulation using a factorial design on two dominant peatland vegetation types (Calluna vulgaris and Sphagnum Spp.) and a peat soil collected from a drinking water catchment in Exmoor National Park, UK. Temperature and rainfall were set to represent baseline and future conditions under the UKCP09 2080s high emissions scenario for July and August. DOC leachate then underwent standard water treatment of coagulation/flocculation before chlorination. C. vulgaris leached more DOC than Sphagnum Spp. (7.17 versus 3.00 mg g(-1)) with higher specific ultraviolet (SUVA) values and a greater sensitivity to climate, leaching more DOC under simulated future conditions. The peat soil leached less DOC (0.37 mg g(-1)) than the vegetation and was less sensitive to climate. Differences in coagulation removal efficiency between the DOC sources appears to be driven by relative solubilisation of protein-like DOC, observed through the fluorescence peak C/T. Post-coagulation only differences between vegetation types were detected for the regulated disinfection by-products (DBPs), suggesting climate change influence at this scale can be removed via coagulation. Our results suggest current biodiversity restoration programmes to encourage Sphagnum Spp. will result in lower DOC concentrations and SUVA values, particularly with warmer and drier summers. PMID:25262551

  10. 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

    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.

  11. DMS emissions from Sphagnum-dominated wetlands

    NASA Technical Reports Server (NTRS)

    Hines, Mark E.; Demello, William Zamboni; Bayley, Suzanne E.

    1992-01-01

    in peat in the unsaturated zone.

  12. Growing season variability of net ecosystem CO2 exchange and evapotranspiration of a sphagnum mire in the broad-leaved forest zone of European Russia

    NASA Astrophysics Data System (ADS)

    Olchev, A.; Volkova, E.; Karataeva, T.; Novenko, E.

    2013-09-01

    The spatial and temporal variability of net ecosystem exchange (NEE) of CO2 and evapotranspiration (ET) of a karst-hole sphagnum peat mire situated at the boundary between broad-leaved and forest-steppe zones in the central part of European Russia in the Tula region was described using results from field measurements. NEE and ET were measured using a portable measuring system consisting of a transparent ventilated chamber combined with an infrared CO2/H2O analyzer, LI-840A (Li-Cor, USA) along a transect from the southern peripheral part of the mire to its center under sunny clear-sky weather conditions in the period from May to September of 2012 and in May 2013. The results of the field measurements showed significant spatial and temporal variability of NEE and ET that was mainly influenced by incoming solar radiation and ground water level. The seasonal patterns of NEE and ET within the mire were quite different. During the entire growing season the central part of the mire was a sink of CO2 for the atmosphere. NEE reached maximal values in June-July (-6.8 ± 4.2 μmol m-2 s-1). The southern peripheral part of the mire, due to strong shading by the surrounding forest, was a sink of CO2 for the atmosphere in June-July only. ET reached maximal values in the well-lighted central parts of the mire in May (0.34 ± 0.20 mm h-1) mainly because of high air and surface temperatures and the very wet upper peat horizon and sphagnum moss. Herbaceous species made the maximum contribution to the total gross primary production (GPP) in both the central and the peripheral parts of the mire. The contribution of sphagnum to the total GPP of these plant communities was relatively small and ranged on sunny days of July-August from -1.1 ± 1.1 mgC g-1 of dry weight (DW) per hour in the peripheral zone of the mire to -0.6 ± 0.2 mgC g-1 DW h-1 at the mire center. The sphagnum layer made the maximum contribution to total ET at the mire center (0.25 ± 0.10 mm h-1) and the herbaceous

  13. Sulfate reduction in peat from a new jersey pinelands cedar swamp.

    PubMed

    Spratt, H G; Morgan, M D; Good, R E

    1987-07-01

    Microbial sulfate reduction rates in acidic peat from a New Jersey Pine Barrens cedar swamp in 1986 were similar to sulfate reduction rates in freshwater lake sediments. The rates ranged from a low of 1.0 nmol cm day in February at 7.5- to 10.0-cm depth to 173.4 nmol cm day in July at 5.0- to 7.5-cm depth. The presence of living Sphagnum moss at the surface generally resulted in reduced rates of sulfate reduction. Pore water sulfate concentrations and water table height also apparently affected the sulfate reduction rate. Concentrations of sulfate in pore water were nearly always higher than those in surface water and groundwater, ranging from 26 to 522 muM. The elevated pore water sulfate levels did not result from the evapotranspiratory concentration of infiltrating stream water or groundwater, but probably resulted from oxidation of reduced sulfur compounds, hydrolysis of ester sulfates present in the peat, or both. The total sulfur content of peat that had no living moss at the surface was 164.64 +/- 1.5 and 195.8 +/- 21.7 mumol g (dry weight) for peat collected from 2.5 to 5.0 and 7.5 to 10.0 cm, respectively. Organosulfur compounds accounted for 84 to 88% of the total sulfur that was present in the peat. C-bonded sulfur accounted for 91 to 94% of the organic sulfur, with ester sulfate being only a minor constituent. Reduced inorganic sulfur species in peat from 2.5 to 7.5 cm were dominated by H(2)S-FeS (68%), while pyritic sulfide was the predominant inorganic sulfur species in the peat from depths of 7.5 to 10.0 cm (75%). PMID:16347371

  14. Sulfate Reduction in Peat from a New Jersey Pinelands Cedar Swamp †

    PubMed Central

    Spratt, Henry G.; Morgan, Mark D.; Good, Ralph E.

    1987-01-01

    Microbial sulfate reduction rates in acidic peat from a New Jersey Pine Barrens cedar swamp in 1986 were similar to sulfate reduction rates in freshwater lake sediments. The rates ranged from a low of 1.0 nmol cm−3 day−1 in February at 7.5- to 10.0-cm depth to 173.4 nmol cm−3 day−1 in July at 5.0- to 7.5-cm depth. The presence of living Sphagnum moss at the surface generally resulted in reduced rates of sulfate reduction. Pore water sulfate concentrations and water table height also apparently affected the sulfate reduction rate. Concentrations of sulfate in pore water were nearly always higher than those in surface water and groundwater, ranging from 26 to 522 μM. The elevated pore water sulfate levels did not result from the evapotranspiratory concentration of infiltrating stream water or groundwater, but probably resulted from oxidation of reduced sulfur compounds, hydrolysis of ester sulfates present in the peat, or both. The total sulfur content of peat that had no living moss at the surface was 164.64 ± 1.5 and 195.8 ± 21.7 μmol g (dry weight)−1 for peat collected from 2.5 to 5.0 and 7.5 to 10.0 cm, respectively. Organosulfur compounds accounted for 84 to 88% of the total sulfur that was present in the peat. C-bonded sulfur accounted for 91 to 94% of the organic sulfur, with ester sulfate being only a minor constituent. Reduced inorganic sulfur species in peat from 2.5 to 7.5 cm were dominated by H2S-FeS (68%), while pyritic sulfide was the predominant inorganic sulfur species in the peat from depths of 7.5 to 10.0 cm (75%). PMID:16347371

  15. Recent atmospheric dust deposition in an ombrotrophic peat bog in Great Hinggan Mountain, Northeast China.

    PubMed

    Bao, Kunshan; Xing, Wei; Yu, Xiaofei; Zhao, Hongmei; McLaughlin, Neil; Lu, Xianguo; Wang, Guoping

    2012-08-01

    Recent deposition of atmospheric soil dust (ASD) was studied using (210)Pb-dated Sphagnum-derived peat sequences from Great Hinggan Mountain in northeast China. Physicochemical indices of peat including dry bulk density, water content, ash content, total organic carbon and mass magnetic susceptibility were measured. Acid-insoluble concentration of lithogenic metals (Al, Ca, Fe, Mn, V and Ti) were measured using ICP-AES. The basic physicochemical properties were used to assess the peat trophic status and indicated that the sections above 45-60 cm are rain-fed peat. A continuous record of ASD fluxes over the past 150 years was reconstructed based on the geochemical data obtained from the ombrotrophic zone, and the average input rate of ASD is 13.4-68.1 g m(-2) year(-1). The source of soil dust deposited in peat was dominated by the long-range transport of mineral aerosol from the drylands in north China and Mongolia. The temporal variation of ASD fluxes in the last 60 years coincides well with the meteorological records of dust storm frequency during 1954-2002 in north China. This suggests that the reconstructed sequence of atmospheric dust deposition is reliable and we can look back in time at the dust evolution before 1949. Dust storm events were observed occasionally in the late Qing dynasty, and their frequency and intensity were smaller than dust weather occurring in recent times. Four peaks of ASD fluxes were distinguished and correlated with the historical events at that time. This study presents the first atmospheric soil dust data in peat records in northeast China, and complements a global database of peat bog archives of atmospheric deposition. The results reflect the patterns of local environmental change over the past century in north China and will be helpful in formulating policies to achieve sustainable and healthy development. PMID:22664536

  16. 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.

  17. 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.

  18. The peats of Costa Rica

    SciTech Connect

    Thayer, G.R.

    1991-01-01

    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 identified 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.

  19. The impact of peat harvesting and natural regeneration on the water balance of an abandoned cutover bog, Quebec

    NASA Astrophysics Data System (ADS)

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

    2001-02-01

    Harvested sites rarely return to functional ecosystems after abandonment because drainage and peat extraction lower the water table and expose relatively decomposed peat, which is hydrologically unsuitable for Sphagnum moss re-establishment. Some natural regeneration of Sphagnum has occurred in isolated pockets on traditionally harvested (block-cut) sites, for reasons that are poorly understood, but are related to natural functions that regulate runoff and evaporation. This study evaluates the water balance of a naturally regenerated cutover bog and compares it with a nearby natural bog of similar size and origin, near Riviere du Loup, Quebec. Water balance results indicated that evapotranspiration was the major water loss from the harvested bog, comprising 92 and 84% of total outputs (2·9 mm day-1) during the 1997 and 1998 seasons, respectively. Despite denser tree cover at the harvested site, evapotranspiration from the natural bog was similar, although less spatially variable. At the harvested site, evaporative losses ranged from 1·9 mm day-1 on raised baulks and roads to 3·6 mm day-1 from moist surfaces with Sphagnum. Although about half of the ditches were inactive or operating at only a fraction of their original efficiency, runoff was still significant at 12 and 24% of precipitation during the 1997 and 1998 study seasons, respectively. This compares with negligible rates of runoff at the natural bog. Thus the cutover bog, although abandoned over 25 years ago, has not regained its hydrological function. This is both a cause and effect of its inability to support renewed Sphagnum regeneration. Without suitable management (e.g. blocking ditches), this site is not likely to improve for a very long time.

  20. Buoyancy-driven flow in a peat moss layer as a mechanism for solute transport

    PubMed Central

    Rappoldt, Cornelis; Pieters, Gert-Jan J. M.; Adema, Erwin B.; Baaijens, Gerrit J.; Grootjans, Ab P.; van Duijn, Cornelis J.

    2003-01-01

    Transport of nutrients, CO2, methane, and oxygen plays an important ecological role at the surface of wetland ecosystems. A possibly important transport mechanism in a water-saturated peat moss layer (usually Sphagnum cuspidatum) is nocturnal buoyancy flow, the downward flow of relatively cold surface water, and the upward flow of warm water induced by nocturnal cooling. Mathematical stability analysis showed that buoyancy flow occurs in a cooling porous layer if the system's Rayleigh number (Ra) exceeds 25. For a temperature difference of 10 K between day and night, a typical Ra value for a peat moss layer is 80, which leads to quickly developing buoyancy cells. Numerical simulation demonstrated that fluid flow leads to a considerable mixing of water. Temperature measurements in a cylindrical peat sample of 50-cm height and 35-cm diameter were in agreement with the theoretical results. The nocturnal flow and the associated mixing of the water represent a mechanism for solute transport in water-saturated parts of peat land and in other types of terrestrializing vegetation. This mechanism may be particularly important in continental wetlands, where Ra values in summer are often much larger than the threshold for fluid flow. PMID:14657381

  1. Smouldering fires and environmental reconstructions using ombrotrophic peat cores

    NASA Astrophysics Data System (ADS)

    Zaccone, Claudio; Rein, Guillermo; Ciavatta, Claudio; Knicker, Heike; Shotyk, William; Miano, Teodoro M.

    2014-05-01

    Peatlands are the soil organic matter-rich ecosystem most affected by fire. When they burn, the dominating phenomenon is not flaming but rather smouldering combustion. Recent estimates suggest that mean annual greenhouse gas emissions from smouldering peat fires are equivalent to 15% of global anthropogenic emissions. Furthermore, warmer temperatures at high latitudes are already resulting in unprecedented permafrost thaw, leaving large organic C pools exposed to fires for the first time in millennia. Much of our knowledge of past fire events is based on the abundance of charcoal particles in fossil and sub-fossil records. The combustion of char by the smouldering process implies that the record of past fires in peat cores may be entirely hidden. Three Sphagnum peat columns (26 cm deep) having different initial moisture contents (MC, in dry weight basis), i.e., 50, 100 and 200%MC, were prepared for this study. In a previous work, we tried to identify palaeofires by the physical and chemical signature that they leave behind in the soil profile. In the present one, we employ solid-state Nuclear Magnetic Resonance (NMR) and Isotope-Ratio Mass Spectroscopy (IRMS) characterization of peat organic matter, as well as results regarding and measure polycyclic aromatic hydrocarbons (PAH) production and metal concentration changes following smouldering fires. The 15N spectrum of fresh peat (FP) used as control shows only an amide signal, which is in agreement with the 13C NMR spectrum where mainly signals of carbohydrates and alkyl C can be observed. Further signals can be observed in the aromatic region, most probably due to lignin derivatives. Following the smouldering event, selected peat samples from both the 50% and 100% MC series show signals supporting the occurrence of fire. In detail, the 15N-signals between -200 and -250 ppm are typical for pyrrole or indole type N. This is in accordance with the 13C NMR spectra showing considerable intensity in the aromatic region

  2. Effects of bryophytes on succession from alkaline marsh to Sphagnum bog

    SciTech Connect

    Glime, J.M.; Wetzel, R.G.; Kennedy, B.J.

    1982-10-01

    The alkaline eastern marsh of Lawrence Lake, a marl lake in southwestern Michigan, was sampled by randomly placed line transects to determine the bryophyte cover and corresponding vascular plant zones. Cluster analysis indicated three distinct bryophyte zones which correspond with the recognized vascular plant zones. Mosses occupied over 50% of the surface in some areas. Invasion of Sphagnum, vertical zonation of the mosses on hummocks, zonation with distance from the lake, the abundance of non-Sphagnum moss hummocks, and the ability of the non-Sphagnum species to lower the pH of marsh water during laboratory incubations are evidence that non-Sphagnum mosses facilitate succession from alkaline marsh to Sphagnum bog.

  3. Dynamics of methane ebullition from a peat monolith revealed from a dynamic flux chamber system

    NASA Astrophysics Data System (ADS)

    Yu, Zhongjie; Slater, Lee D.; Schäfer, Karina V. R.; Reeve, Andrew S.; Varner, Ruth K.

    2014-09-01

    Methane (CH4) ebullition in northern peatlands is poorly quantified in part due to its high spatiotemporal variability. In this study, a dynamic flux chamber (DFC) system was used to continuously measure CH4 fluxes from a monolith of near-surface Sphagnum peat at the laboratory scale to understand the complex behavior of CH4 ebullition. Coincident transmission ground penetrating radar measurements of gas content were also acquired at three depths within the monolith. A graphical method was developed to separate diffusion, steady ebullition, and episodic ebullition fluxes from the total CH4 flux recorded and to identify the timing and CH4 content of individual ebullition events. The results show that the application of the DFC had minimal disturbance on air-peat CH4 exchange and estimated ebullition fluxes were not sensitive to the uncertainties associated with the graphical model. Steady and episodic ebullition fluxes were estimated to be averagely 36 ± 24% and 38 ± 24% of the total fluxes over the study period, respectively. The coupling between episodic CH4 ebullition and gas content within the three layers supports the existence of a threshold gas content regulating CH4 ebullition. However, the threshold at which active ebullition commenced varied between peat layers with a larger threshold (0.14 m3 m-3) observed in the deeper layers, suggesting that the peat physical structure controls gas bubble dynamics in peat. Temperature variation (23°C to 27°C) was likely only responsible for small episodic ebullition events from the upper peat layer, while large ebullition events from the deeper layers were most likely triggered by drops in atmospheric pressure.

  4. 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. PMID:26301685

  5. Application of static and dynamic enclosures for determining dimethyl sulfide and carbonyl sulfide exchange in Sphagnum peatlands: Implications for the magnitude and direction of flux

    NASA Technical Reports Server (NTRS)

    De Mello, William Z.; Hines, Mark E.

    1994-01-01

    A static enclosure method was applied to determine the exchange of dimethyl sulfide (DMS) and carbonyl sulfide (OCS) between the surface of Sphagnum peatlands and the atmosphere. Measurements were performed concurrently with dynamic (flow through) enclosure measurements with sulfur-free air used as sweep gas. This latter technique has been used to acquire the majority of available data on the exchange of S gases between the atmosphere and the continental surfaces and has been criticized because it is thought to overestimate the true flux of gases by disrupting natural S gas gradients. DMS emission rates determined by both methods were not statistically different between 4 and greater than 400 nmol/sq m/h, indicating that previous data on emissions of at least DMS are probably valid. However, the increase in DMS in static enclosures was not linear, indicating the potential for a negative feedback of enlosure DMS concentrations on efflux. The dynamic enclosure method measured positive OCS flux rates (emission) at all sites, while data using static enclosures indicated that OCS was consumed from the atmosphere at these same sites at rates of 3.7 to 55 nmol/sq m/h. Measurements using both enclosure techniques at a site devoid of vegetation showed that peat was a source of both DMS and OCS. However, the rate of OCS efflux from decomposing peat was more than counterbalanced by OCS consumption by vegetation, including Sphagnum mosses, and net OCS uptake occurred at all sites. We propose that all wetlands are net sinks for OCS.

  6. Trophic Status Controls Mercury Methylation Pathways in Northern Peats

    NASA Astrophysics Data System (ADS)

    Hines, M. E.; Zhang, L.; Barkay, T.; Krabbenhoft, D. P.; Schaefer, J.; Hu, H.; Sidelinger, W.; Liu, X.; Wang, Y.

    2015-12-01

    Methyl mercury (MeHg) can be produced by a variety of microbes including syntrophs, methanogens, acetogens, and fermenters, besides sulfate (SO42-, SRB) and iron- reducing bacteria. Many freshwater wetlands are deficient in electron acceptors that support the traditional respiratory pathways of methylation, yet they accumulate high levels of MeHg. To investigate methylation in these wetlands and to connect these pathways with vegetation and microbial communities, incubation experiments were conducted using peats from 26 sites in Alaska. The sites were clustered using multiple factor analysis based on pH, temp, CH4 and volatile fatty acids production rates, and surface vegetation composition. Three clusters were generated and corresponded to three trophic levels that were manifested by three pH levels (3.5, 4.5, and 5). Hg methylation activity in laboratory incubations was determined using the short-lived radioisotope 197Hg. In the low pH, Sphagnum-dominated cluster, methylation rates were less than 1% day-1 and likely conducted by primary fermenters. Conversely, the high pH trophic cluster dominated by Carex aquatilis and active syntrophy exhibited Hg methylation rates as high as 12% day-1. In intermediate sites, rich in Sphagnum magellanicum with less Carex, a gradient in syntrophy and Hg methylation paths was observed. Amendments with process-stimulators and inhibitors revealed no evidence of SO42- reduction, but suggested that SRB, metabolizing either syntrophically with methanogens and/or by fermentation, likely methylated Hg. While on going metatranscriptomics studies are required to verify the role of syntrophs, fermenters, and methanogens as methylators, these results revealed that Hg methylation pathways change greatly along trophic gradients with a dominance of respiratory pathways in mineral-rich sites, syntrophy dominance in intermediate sites, and fermentation dominance in nutrient-poor sites.

  7. 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

  8. The peats of Costa Rica

    SciTech Connect

    Thayer, G.R.; Williamson, K.D. Jr. ); Ramirez, O. )

    1991-04-01

    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. Peat 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.

  9. Second technical contractors' conference on peat

    SciTech Connect

    Not Available

    1980-01-01

    This conference reported the status of the US Department of Energy Peat Program. The program includes peat resource surveys of eleven states, peat gasification process and equipment studies, dewatering studies, and environmental and socioeconomic factors in the development of peat technology. Separate abstracts were prepared for selected papers. (CKK)

  10. 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

  11. For peat's sake

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    With climate models predicting a sharp increase in global temperature over the coming decades, three scientists are investigating how this warming trend will affect a huge band of peat wetlands that ring the Northern Hemisphere around Alaska, Canada, Scandinavia, and the former Soviet Union.“We are concerned about the impact of a major climate change on these ecosystems with tons of soil carbon,” says Scott Bridgham, a professor at the University of Notre Dame, who is a principal investigator in the study along with Jiquan Chen of Michigan Technological University and John Pastor of the University of Minnesota. Bridgham says that peatlands make up just 2.5% of the Earth's surface but contain about one-third of its soil carbon pool.

  12. Soil temperature synchronisation improves estimation of daily variation of ecosystem respiration in Sphagnum peatlands

    NASA Astrophysics Data System (ADS)

    D'Angelo, Benoît; Gogo, Sébastien; Le Moing, Franck; Jégou, Fabrice; Guimbaud, Christophe; Laggoun, Fatima

    2015-04-01

    comparison was performed using RMSE (goodness-of-fit) and AIC (goodness-of-fit and model complexity) as indicators to assess their relative quality. Both indicators showed a wide variation between sites. However, for each site differences between synchronised and non-synchronised data were larger than the differences between models equations. According to the AIC, models using synchronised data produced better ER estimations than models using non-synchronised data, at all depth. RMSE support this result for all sites for superficial peat layer. In some locations, mainly Frasne, synchronised data at 5 cm depth provide better estimation than air temperature, i.e. 25.0 vs. 26.4 for RMSE and 337.1 vs. 379.8 for AIC, respectively. The equation of the most appropriate model varies between sites, but the differences between them are small. At a daily scale, data synchronisation in Sphagnum peatlands improves ER estimation regardless of the model used. Moreover, to estimate ER flux, the use of synchronised data at 5 cm depth seems the most adequate method.

  13. Factors controlling sulfur gas exchange in Sphagnum-dominated wetlands

    NASA Technical Reports Server (NTRS)

    Demello, William Zamboni; Hines, Mark E.; Bayley, Suzanne E.

    1992-01-01

    Atmosphere-peatland exchange of reduced sulfur gases was determined seasonally in fen in NH, and in an artificially-acidified fen at the Experimental Lakes Area (ELA) in Canada. Dimethyl sulfide (DMS) dominated gas fluxes at rates as high as 400 nmol/m(sup -2)hr(sup -1). DMS fluxes measured using enclosures were much higher than those calculated using a stagnant-film model, suggesting that Sphagnum regulated efflux. Temperature controlled diel and seasonal variability in DMS emissions. Use of differing enclosure techniques indicated that vegetated peatlands consume atmospheric carbonyl sulfide. Sulfate amendments caused DMS and methane thiol concentrations in near-surface pore waters to increase rapidly, but fluxes of these gases to the atmosphere were not affected. However, emission data from sites experiencing large differences in rates of sulfate deposition from the atmosphere suggested that chronic elevated sulfate inputs enhance DMS emissions from northern wetlands.

  14. Biological properties of the Chilean native moss Sphagnum magellanicum.

    PubMed

    Montenegro, Gloria; Portaluppi, Mariana C; Salas, Francisco A; Díaz, María F

    2009-01-01

    An ethanol extract prepared from the gametophyte Chilean native moss Sphagnum magellanicum was dried out, weighed and dissolved in distilled water. This extract was then assayed for its antibacterial activity against the G(-) bacteria Azotobacter vinelandii, Erwinia carotovora subsp. carotovora, Enterobacter aerogenes, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Vibrio cholerae, and the G(+) bacteria Staphylococcus aureus subsp. aureus, and Streptococcus type beta. The growth of the cultures of E. carotovora subsp. carotovora, and V. cholerae was inhibited at a concentration of 581 microg/ml of extract, while the cultures of E. coli, S. typhi and Streptococcus type beta were inhibited at a concentration of 1.16 microg/mL of extract. The concentration of phenolic compounds was 4.294 mg/mL; the presence of vanillic, chlorogenic, syringic, caffeic, gallic, 3-4 hydrozybenzoic, p-coumaric and salicylic acids was identified using RP- High Pressure Liquid Chromatography. PMID:19746269

  15. 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

  16. Recent atmospheric Pb deposition at a rural site in southern Germany assessed using a peat core and snowpack, and comparison with other archives

    NASA Astrophysics Data System (ADS)

    Le Roux, Gaël; Aubert, Dominique; Stille, Peter; Krachler, Michael; Kober, Bernd; Cheburkin, Andriy; Bonani, Georges; Shotyk, William

    In a peat bog from Black Forest, Southern Germany, the rate of atmospheric Pb accumulation was quantified using a peat core dated by 210Pb and 14C. The most recent Pb accumulation rate (2.5 mg m -2 y -1) is similar to that obtained from a snowpack on the bog surface, which was sampled during the winter 2002 (1 to 4 mg m -2 y -1). The Pb accumulation rates recorded by the peat during the last 25 yr are also in agreement with published values of direct atmospheric fluxes in Black Forest. These values are 50 to 200 times greater than the "natural" average background rate of atmospheric Pb accumulation (20 μg m -2 y -1) obtained using peat samples from the same bog dating from 3300 to 1300 cal. yr B.C. The isotopic composition of Pb was measured in both the modern and ancient peat samples as well as in the snow samples, and clearly shows that recent inputs are dominated by anthropogenic Pb. The chronology and isotopic composition of atmospheric Pb accumulation recorded by the peat from the Black Forest is similar to the chronologies reported earlier using peat cores from various peat bogs as well as herbarium samples of Sphagnum and point to a common Pb source to the region for the past 150 years. In contrast, Pb contamination occurring before 1850 in southwestern Germany, differs from the record published for Switzerland mainly due to the mining activity in Black Forest. Taken together, the results show that peat cores from ombrotrophic bogs can yield accurate records of atmospheric Pb deposition, provided that the cores are carefully collected, handled, prepared, and analysed using appropriate methods.

  17. Dewatering Peat With Activated Carbon

    NASA Technical Reports Server (NTRS)

    Rohatgi, N. K.

    1984-01-01

    Proposed process produces enough gas and carbon to sustain itself. In proposed process peat slurry is dewatered to approximately 40 percent moisture content by mixing slurry with activated carbon and filtering with solid/liquid separation techniques.

  18. Peat as an energy alternative

    SciTech Connect

    Punwani, D.V.

    1980-07-01

    The importance of developing alternative energy sources to augment supplies of fossil fuels is growing all over the world. Coal, oil shale, tar sands, biomass, solar, geothermal, nuclear, and hydroelectric power have received considerable attention as alternative energy sources. One large energy resource, however, has received little attention until recently. That resource is peat. Although peat is used as an energy source in some countries such as Russia, Ireland, and Finland, it is virtually unexploited in many countries including the United States. This paper provides an understanding of peat: its varieties, abundance, and distribution; its value as an energy alternative; its current and future role as an energy alternative; and the environmental and socioeconomic impacts of large-scale peat utilization.

  19. Spatial and temporal variations of dissolved organic matter dynamics in a disturbed Sphagnum peatland after hydrological restoration

    NASA Astrophysics Data System (ADS)

    Le Moing, Franck; Guirimand-Dufour, Audrey; Jozja, Nevila; Defarge, Christian; D'Angelo, Benoît; Binet, Stéphane; Gogo, Sébastien; Laggoun, Fatima

    2015-04-01

    Peatlands contain a third of the world soil C in spite of their relatively low global area (3% of land area). They can become sources of C because of human disturbances such as drainage. The aim of this work is to assess the effect of an hydrological restoration on a disturbed Sphagnum peatland. It concerns spatial and temporal variations of dissolved organic matter (DOM) dynamics. The investigated site was La Guette peatland (France, N 47°19'44', E 2°17'04', alt. 154m), whose hydrological conditions are influenced by a road passing through its former area. The road drain accelerates drying mechanisms, favouring thus vascular plants settlement to the detriment of specific flora of peatlands (i.e. Sphagnum). Hydrological restoration was undertaken in February 2014. It consisted in building thresholds to slow down drain runoff and to promote the soil rewetting. Two transects of piezometers were settled in independent two hydrological sub-systems: Trans-up and Trans-down. Trans-down is supposed to be influenced by the hydrological restoration, while Trans-up is not. These transects cross the peatland and follow water flow direction until the outlet. Six sampling campaigns were performed before, during and after the vegetation period. Water conductivity and pH were measured on site. Water samples were collected in the piezometers. Samples were filtered in the field at 0.45 μm. Concentrations of dissolved organic carbon (DOC), cations (Na+, K+, Ca2+, Mg2+, NH4+) and anions (Cl-, SO42-, PO43-, NO2-, NO3-) were measured. Absorbance was measured by UV-VIS spectrophotometer to assess SUVA254 and aromaticity of DOM. Three-dimensional excitation-emission matrices (EEM) were undertaken to characterise fluorescent DOM (FDOM). Humification (HIX) and biological (BIX) fluorescence indices were calculated. PARAFAC algorithm was used to treat EEMs. Precipitations and water levels were measured automatically by a weather station and automatic probes, respectively. Rain water was

  20. Physical and chemical characteristics and development of the Changuinola peat deposit of northwestern Panama

    SciTech Connect

    Cohen, A.D.; Raymond, R. Jr.; Thayer, G.; Ramirez, A.

    1987-08-01

    A peat deposit occupying over 80 square kilometers, and averaging 8 meters in thickness, was discovered on the Caribbean coast of northwestern Panama near the town of Changuinola. This deposit occurs inland (behind) the present beach-barrier shoreline. It is thickest in the center and thins toward all edges (as if domed). The surface vegetation in the central regions consists primarily of ombrotrophic plants (especially sedges, grasses, Sphagnum, Sagittaria, and various scattered shrubs). Toward the edges, the deposit has a surface cover of more minerotrophic plants (such as swamp-forest trees, ferns, and palms). Petrographic/botanical analysis of the deposit with depth reveals the presence of five peat types (swamp-forest, sedge-grass-fern, Sagittaria et al., Nymphaea et al., and Rhizophora). Typically peats of the thick, central portions of the deposit are very low in ash and sulfur (less than 2% ash and 0.3% sulfur). Ash contents tend to increase abruptly at the base and more gradually toward the edges of the deposit and sulfur contents increasing gradually toward the ocean and bay. Vertical and lateral variations in botanical, chemical, and physical properties of this deposit can be related to factors that have controlled: (1) the surrounding rocks and water chemistry; (2) the source vegetation; and (3) the environments in which these source ingredients were deposited. 3 refs., 10 figs.

  1. Seven hundred years of peat formation recorded throughout a deep floating mire profile from Central Italy

    NASA Astrophysics Data System (ADS)

    Lobianco, Daniela; D'Orazio, Valeria; Miano, Teodoro; Zaccone, Claudio

    2016-04-01

    Floating mires are defined by the occurrence of emergent vegetation rooted in highly organic buoyant mats that rise and fall with changes in water level. Islands floating and moving on a lake naturally were already described by Pliny the Elder in his Naturalis historia almost two millennia ago. Actually, he devoted a whole chapter of Naturalis historia to "Of Islands Ever Floating and Swimming", reporting how certain isles were always waving and never stood still. The status of "flotant" has been defined transitory; in fact, these small isles often disappear, in most of the cases because of a transition from floating island to firm land during decades is likely to happen. That is why most of the floating islands described by Pliny the Elder (e.g., Lacus Fundanus, Lacus Cutiliensis, Lacus Mutinensis, Lacus Statoniensis, Lacus Tarquiniensis, Lydia Calaminae, Lacus Vadimonis) do not exist anymore. In the present study, peat formation and organic matter evolution were investigated in order to understand how these peculiar environments form, and how stable actually they are. In fact, it is hoped that peat-forming floating mires could provide an exceptional tool for environmental studies, since much of their evolution, as well as the changes of the surrounding areas, is recorded in their peat deposits. A complete, 4-m deep peat core 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 centre. Here, some of the southernmost Italian populations of Sphagnum palustre occur. The 14C age dating of organic sediments isolated from the sample at 385 cm of depth revealed that the island formed ca. 700 yrs ago (620±30 yr BP). The top 100 cm, consisting almost exclusively of Sphagnum mosses, show a very low bulk density (avg., 0.03±0.01 g cm

  2. Seven hundred years of peat formation recorded throughout a deep floating mire profile from Central Italy

    NASA Astrophysics Data System (ADS)

    Lobianco, Daniela; D'Orazio, Valeria; Miano, Teodoro; Zaccone, Claudio

    2016-04-01

    Floating mires are defined by the occurrence of emergent vegetation rooted in highly organic buoyant mats that rise and fall with changes in water level. Islands floating and moving on a lake naturally were already described by Pliny the Elder in his Naturalis historia almost two millennia ago. Actually, he devoted a whole chapter of Naturalis historia to "Of Islands Ever Floating and Swimming", reporting how certain isles were always waving and never stood still. The status of "flotant" has been defined transitory; in fact, these small isles often disappear, in most of the cases because of a transition from floating island to firm land during decades is likely to happen. That is why most of the floating islands described by Pliny the Elder (e.g., Lacus Fundanus, Lacus Cutiliensis, Lacus Mutinensis, Lacus Statoniensis, Lacus Tarquiniensis, Lydia Calaminae, Lacus Vadimonis) do not exist anymore. In the present study, peat formation and organic matter evolution were investigated in order to understand how these peculiar environments form, and how stable actually they are. In fact, it is hoped that peat-forming floating mires could provide an exceptional tool for environmental studies, since much of their evolution, as well as the changes of the surrounding areas, is recorded in their peat deposits. A complete, 4-m deep peat core 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 centre. Here, some of the southernmost Italian populations of Sphagnum palustre occur. The 14C age dating of organic sediments isolated from the sample at 385 cm of depth revealed that the island formed ca. 700 yrs ago (620±30 yr BP). The top 100 cm, consisting almost exclusively of Sphagnum mosses, show a very low bulk density (avg., 0.03±0.01 g cm

  3. A new peat bog testate amoeba transfer function and quantitative palaeohydrological reconstructions from southern Patagonia

    NASA Astrophysics Data System (ADS)

    van Bellen, S.; Mauquoy, D.; Payne, R.; Roland, T. P.; Hughes, P. D.; Daley, T. J.; Street-Perrot, F. A.; Loader, N.

    2013-12-01

    Testate amoebae have been used extensively as proxies for environmental change and palaeoclimate reconstructions in European and North American peatlands. The presence of these micro-organisms in surface samples is generally significantly linked to the local water table depth (WTD) and preservation of the amoeba shells downcore allows for millennial length water table reconstructions. Peat bog archive records in southern Patagonia are increasingly the focus of palaeoecological research due to the possibility of detecting changes in the Southern Westerlies. These Sphagnum magellanicum-dominated peat bogs are characterised by a wide range of water table depths, from wet hollows to high hummocks (>100 cm above the water table). Here we present the first transfer function for this region along with ~2k-year palaeorecords from local peat bogs. A modern dataset (155 samples) was sampled along transects from five bogs in 2012 and 2013. Measurements of WTD, pH and conductivity were taken for all samples. The transfer function model was based on the 2012 dataset, while the 2013 samples served as an independent test set to validate the model. Besides the standard leave-one-out cross-validation, we applied leave-one-site-out and leave-one transect-out cross-validation, which are effective means of verifying the degree of clustering in the dataset. To ensure that the environmental gradient had been evenly sampled we quantified the root-mean-squared error of prediction (RMSEP) individually for segments of this gradient. Ordinations showed a clear hydrological gradient in amoeba assemblages, with the dominant Assulina muscorum at the dry end and Amphitrema wrightianum and Difflugia globulosa at the wet end. Canonical correspondence analysis showed that WTD was the most important environmental variable, accounting for 18% of the variance in amoeba assemblages. A weighted averaging-partial least squares model showed best performance in cross-validation, using the 2013 data as an

  4. High-resolution Record of Holocene Climate, Vegetation, and Fire from a Raised Peat Bog, Prince Edward Island, Canadian Maritimes

    NASA Astrophysics Data System (ADS)

    Peros, M. C.; Chan, K.; Ponsford, L.; Carroll, J.; Magnan, G.

    2014-12-01

    Raised peat bogs receive all precipitation and nutrients from the atmosphere and are thus widely used archives for information on past environments and climates. In this paper we provide high-resolution multi-proxy data from a raised bog from northeastern Prince Edward Island, located in the Gulf of St. Lawrence, Canada. We studied testate amoeba (a proxy for water table depth), macrocharcoal (a proxy for local-scale fire), peat humification (a proxy for decomposition), plant macrofossils (indicative of local-scale vegetation), and organic matter content (yielding carbon accumulation rates) from a 5.5 m long core lifted from the center of Baltic Bog. Eleven AMS radiocarbon dates show that peat accumulation began before 9000 cal yr BP and continued almost uninterrupted until the present. The macrofossil data show that a transition from a sedge-dominated fen to a sphagnum-dominated bog occurred around 8000 cal yr BP, and sphagnum remained dominant in the bog throughout most of the Holocene. A testate amoeba-based reconstruction of water table depth indicates that conditions were drier during the early Holocene (~8000 to 5000 cal yr BP) and became gradually wetter into the late Holocene. In addition, a number of higher frequency shifts in precipitation are inferred throughout the Holocene on the basis of the testate amoeba and humification results. The macrocharcoal evidence indicates fire—probably in the surrounding forest—was relatively more common during the early Holocene, perhaps due to drier climate conditions. A large influx of charcoal at around 2000 cal yr BP suggests the presence of one or more major fires at this time, and a concurrent decrease in the rate of peat accumulation indicates the fire may have affected the bog itself. The data from Baltic Bog is broadly comparable to other proxy data (in particular pollen studies) from the Canadian Maritimes. This work is important because it: 1) helps us better understand the role of hydroclimatic

  5. 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

  6. Eutrophic mire, its characteristics and modern conditions of peat genesis

    NASA Astrophysics Data System (ADS)

    Inisheva, L. I.; Golubina, O. A.; Zaplatnikova, Yu. D.; Dubrovskaya, L. I.

    2009-04-01

    The study of structure functional organization of Siberian mire ecosystems is the base of after-effects influence of their reclamation on global changes of biosphere. The aim of this investigation is to study the structure functional organization of eutrophic mire ecosystem "Tagan". Peat deposit "Tagan" (West Siberia, 20 kilometers near Tomsk) is situated on the second flood-plain terrace of the river Tom of ancient flow channel. Maximum power of peat deposit is 9.3 meters. Subsoil is made up from sand, more seldom from loamy sand and loam. Eutrophic vegetation covers almost the whole mire. It is presented by woody sedge, sedge, sedge-moss and grass undershrub phytocenoses. The oligotrophic vegetation is presented by Sphagnum pine cotton-grass phytocenosis. There were organized three observation points on the mire in 2007. They watched dynamics of hydrothermic, redox, biological, hydrochemical regimes. There were studied physicochemical properties at given points. Peats with normal ash basically refer to grass, woody grass group of lowland type. They are characterized by high degree of decomposition which is increased down deposit. Group composition of organic matters of investigated peats showed that bitumen content in peat changes from 1.4 to 3.56%, and humid acids content is within the limits of 16.67 - 44.34 %. Water-soluble and hardly-hydrolyzed matters are contained in quantity of 19.04 - 49.76% of the whole dry peat mass. The overall nitrogen content changes within the limits of 1.76 - 3.52%. It is presented mainly by fraction of unhydrolyzed nitrogen (72.07 - 95.67% of the whole nitrogen). Highly-hydrolyzed nitrogen is the most available reserve of mineral compound of nitrogen and its content changes within the limits of 0.18 - 4.79 of the overall nitrogen. 2008 year is characterized as an average year at conditions of moistening and heat providing. Investigations, made during this year, revealed the following results. Bog waters were kept at a surface

  7. Environmental controls of greenhouse gas release in a restoring peat bog in NW Germany

    NASA Astrophysics Data System (ADS)

    Glatzel, S.; Forbrich, I.; Krüger, C.; Lemke, S.; Gerold, G.

    2008-01-01

    In Central Europe, most bogs have a history of drainage and many of them are currently being restored. Success of restoration as well as greenhouse gas exchange of these bogs is influenced by environmental stress factors as drought and atmospheric nitrogen deposition. We determined the methane and nitrous oxide exchange of sites in the strongly decomposed center and less decomposed edge of the Pietzmoor bog in NW Germany in 2004. Also, we examined the methane and nitrous oxide exchange of mesocosms from the center and edge before, during, and following a drainage experiment as well as carbon dioxide release from disturbed unfertilized and nitrogen fertilized surface peat. In the field, methane fluxes ranged from 0 to 3.8 mg m-2 h-1 and were highest from hollows. Field nitrous oxide fluxes ranged from 0 to 574 μg m-2 h-1 and were elevated at the edge. A large Eriophorum vaginatum tussock showed decreasing nitrous oxide release as the season progressed. Drainage of mesocosms decreased methane release to 0, even during rewetting. There was a tendency for a decrease of nitrous oxide release during drainage and for an increase in nitrous oxide release during rewetting. Nitrogen fertilization did not increase decomposition of surface peat. Our examinations suggest a competition between vascular vegetation and denitrifiers for excess nitrogen. We also provide evidence that the von Post humification index can be used to explain greenhouse gas release from bogs, if the role of vascular vegetation is also considered. An assessment of the greenhouse gas release from nitrogen saturated restoring bogs needs to take into account elevated release from fresh Sphagnum peat as well as from sedges growing on decomposed peat. Given the high atmospheric nitrogen deposition, restoration will not be able to achieve an oligotrophic ecosystem in the short term.

  8. Terrestrial isopod community as indicator of succession in a peat bog

    PubMed Central

    Antonović, Ivan; Brigić, Andreja; Sedlar, Zorana; Bedek, Jana; Šoštarić, Renata

    2012-01-01

    Abstract Terrestrial isopods were studied in the Dubravica peat bog and surrounding forest in the northwestern Croatia. Sampling was conducted using pitfall traps over a two year period. Studied peat bog has a history of drastically decrease in area during the last five decades mainly due to the process of natural succession and changes in the water level. A total of 389 isopod individuals belonging to 8 species were captured. Species richness did not significantly differ between bog, edge and surrounding forest. High species richness at the bog is most likely the result of progressive vegetation succession, small size of the bog and interspecific relationships, such as predation. With spreading of Molinia grass on the peat bog, upper layers of Sphagnum mosses become less humid and probably more suitable for forest species that slowly colonise bog area. The highest diversity was found at the edge mainly due to the edge effect and seasonal immigration, but also possibly due to high abundance and predator pressure of the Myrmica ants and lycosid spiders at the bog site. The most abundant species were Trachelipus rathkii and Protracheoniscus politus, in the bog area and in the forest, respectively. Bog specific species were not recorded and the majority of the species collected belong to the group of tyrphoneutral species. However, Hyloniscus adonis could be considered as a tyrphoxenous species regarding its habitat preferences. Most of collected isopod species are widespread eurytopic species that usually inhabit various habitats and therefore indicate negative successive changes or degradation processes in the peat bog. PMID:22536107

  9. Late Holocene Peat Growth at the Northern Siberian Periphery and its Relation to Arctic Climate Change

    NASA Astrophysics Data System (ADS)

    Bauch, H. A.; Abramova, E.; Alenius, T.; Saarnisto, M.

    2014-12-01

    During the last postglacial evolution of the shallow northern Siberian shelf systems regional sea level in the Arctic came to its Holocene highstand some time between 5 to 6 ka. After that time a general stabilization of the sedimentary regime occurred. That is well noted in a drastic decrease in sedimentation rates observed in all sediment cores taken from middle to outer shelf water depths of the Laptev Sea. But, at water depths lower than 30 meters - i.e., in the inner shelf and nearer to the coasts - sedimentation continued at relatively higher rates, presumably due to input of terrigenous material from river runoff as well as coastal erosion. Compared with that latter process, the huge Lena Delta should comprise a region of sediment catchment where aggradation wins over erosion. However, little is known about the detailed history of this delta during the second half of the Holocene. In order to gain more insight into this issue we have investigated three islands within the Lena Delta. All of these are comprised of massive peat of several meters in thickness. Picking discrete specimens of water mosses (Sphagnum) only, we have radiocarbon-dated these peat sections. The depth/age relation of the sampled profiles reflect the growth rate of peat. It shows that the islands' history above the present-day delta-sea level is about 4000 yrs. old. Moreover, a significant change in peat growth occurred after 2500 yrs BP in both, accumulation and composition, and allows the conclusion of a major shift in Arctic environmental conditions since then. Thus, our results may add further information also for other coastal studies, as the ongoing degradation of the rather vulnerable permafrost coast in the Laptev Sea and elsewhere along the North Siberian margin is often mentioned in context with recent Arctic climate change due to global warming.

  10. Smouldering fire signatures in peat and their implications for palaeoenvironmental reconstructions

    NASA Astrophysics Data System (ADS)

    Zaccone, Claudio; Rein, Guillermo; D'Orazio, Valeria; Hadden, Rory M.; Belcher, Claire M.; Miano, Teodoro M.

    2014-07-01

    Peatland ecosystems are valued as natural archives of past climatic and vegetation changes and as such their study is essential for palaeoenvironmental reconstructions over millennia. Fires in peatlands are dominated by smouldering combustion which is the self-sustained, slow, low temperature, flameless form of burning. Most studies on peat fires to date have focused on ignition conditions, C losses or atmospheric emissions, but there is a significant gap in the understanding of the evolution of organic matter (OM) following smouldering. A key feature of smouldering fires is that they consume most of the pyrogenic char produced. Consequently, it may be that most smouldering fires are simply not visible using standard palaeontological techniques. Here we present the possibility of identifying palaeofires by following their physical and chemical signature along a peat profile. We have undertaken laboratory experiments on Sphagnum peat columns and measured physical, chemical and spectroscopic changes of OM features induced by smouldering on samples of varying moisture content. We reveal that there is a higher production of aromatic and condensed molecules, an increase of the total N and a decrease of the C/N ratio, besides significant variations of pH, electrical conductivity and ash content. Several of these changes have, in previous studies, been taken to be indicative of alterations in atmospheric dust deposition and climate-driven changes (e.g., vegetation, water table fluctuation, decomposition and mineralization processes), but are also produced by smouldering fires. Our results imply that smouldering fires should therefore also be considered in climatic and floral reconstructions drawn from peat cores and that these additional physical and chemical changes may serve to enhance our understanding of palaeofire histories.

  11. Artificial radioactivity in fuel peat and peat ash in Finland after the Chernobyl accident

    SciTech Connect

    Mustonen, R.A.; Reponen, A.R.; Jantunen, M.J.

    1989-04-01

    The accident at the Chernobyl nuclear power plant in April 1986 caused very uneven deposition of radionuclides in Finland. The deposited radionuclides were found in relatively high concentrations in fuel peat and especially in peat ash because a thin surface layer of peat-production bogs was extracted as fuel peat soon after the fallout occurred. Concentrations of artificial radionuclides in fuel peat and peat ash were measured at six peat-fired power plants in Finland throughout the heating season 1986-87. Concentrations of /sup 137/Cs in composite peat samples varied between 30 and 3600 Bq kg-1 dry weight and in ash samples between 600 and 68,000 Bq kg-1. High concentrations in peat ash caused some restrictions to the utilization of peat ash for various purposes.

  12. CO2 and CH4 Net Carbon Flux from a high-carbon peatland in Northern Minnesota: Plot scale observations of the Shrub, forb, Sphagnum and microbial community

    NASA Astrophysics Data System (ADS)

    Phillips, J. R.; Hanson, P. J.; Riggs, J.

    2013-12-01

    Significant uncertainty exists regarding the fate of stored peatland carbon under future climate warming scenarios. Methods have been developed to track net flux of CO2 and CH4 from experimental warming plots at a scale appropriate to the in situ biological community. Surface flux measurements of CO2 and CH4 were made using and open-path analyzers over and area of 1.13 m2 within each of our 16 plots. A custom-designed chamber encloses the hummock-hollow topography and allows point in time measurements of the shrub, forb, Sphagnum and the complex microbial community complex. These observations are made with ambient light and imposed dark conditions to allow estimates of net community daytime and night respiratory processes. Sphagnum hollow temperatures, water table levels, hummock moisture levels, and recent PAR as a potential surrogate for labile C are all being evaluated as drivers of net CO2-C and CH4-C flux. Periodic observations from August 2011 through July 2013 show obvious seasonal trends with temperature being the obvious driving variable. During this ';wet' time period surface drying and lower water table depths have not been seen to be key drivers of net C flux. Midwinter conditions with a frozen peat surface produce zero CO2 and CH4 flux. Maximum net CO2 flux in mid summer shows daytime surface uptake values near -6 to -7 μmol m-2 s-1 and night loss rates of 6 to 7 μmol m-2 s-1. Maximum midsummer observed CH4 flux for this bog range from 0.4 to 0.5 μmol m-2 s-1. Integrating temperature dependent models of net flux across annual periods showed next CO2-C and net CH4-C flux to be 850 and 20 g C m-2 y-1, respectively. Sequential clipping of vegetation layers showed that the shrub (LAI = ~0.5 m2 m-2) and the forb/sedge layer (LAI = ~1 m2 m-2) dominated net carbon uptake during daytime periods while shading the Sphagnum layer (LAI >1 m2 m-2), but had limited impact on dark community respiration likely dominated by the subsurface microbial community. A

  13. 46 CFR 148.290 - Peat moss.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 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 moss must be stockpiled under cover to allow drainage and reduce its moisture content. (b) The...

  14. 46 CFR 148.290 - Peat moss.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 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 moss must be stockpiled under cover to allow drainage and reduce its moisture content. (b) The...

  15. 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 moss must be stockpiled under cover to allow drainage and reduce its moisture content. (b) The...

  16. 46 CFR 148.290 - Peat moss.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 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 moss must be stockpiled under cover to allow drainage and reduce its moisture content. (b) The...

  17. Benthic plant communities in acidic Lake Colden, New York: Sphagnum and the algal mat

    SciTech Connect

    Hendrey, G R; Vertucci, J A

    1980-03-01

    Lake Colden, in the central Adirondack Mountains of New York State is botanically similar to acidified lakes in Sweden. Acidification of some Swedish lakes has been associated with an expansion of Sphagnum, primarily in shallow, sheltered littoral areas but also to depths of 18m. During a brief botanical survey on 24-25 July 1979, we observed a dense meadow of Sphagnum pylaesii around much of the shoreline of Lake Colden. Plant community composition was determined by a visual estimate of cover along a single typical transect and through underwater photography on 28-29 August 1979. Water samples were collected and returned to our laboratory for analyses several days later. Sample pH was determined by potentiometry and alkalinity by multiple end point titrations. Biomass samples were also taken of the Sphagnum mat community and dry weight was determined. Chemical content of plant tissue was analyzed.

  18. A Greener Arctic: Vascular Plant Litter Input in Subarctic Peat Bogs Changes Soil Invertebrate Diets and Decomposition Patterns

    NASA Astrophysics Data System (ADS)

    Krab, E. J.; Berg, M. P.; Aerts, R.; van Logtestijn, R. S. P.; Cornelissen, H. H. C.

    2014-12-01

    Climate-change-induced trends towards shrub dominance in subarctic, moss-dominated peatlands will most likely have large effects on soil carbon (C) dynamics through an input of more easily decomposable litter. The mechanisms by which this increase in vascular litter input interacts with the abundance and diet-choice of the decomposer community to alter C-processing have, however, not yet been unraveled. We used a novel 13C tracer approach to link invertebrate species composition (Collembola), abundance and species-specific feeding behavior to C-processing of vascular and peat moss litters. We incubated different litter mixtures, 100% Sphagnum moss litter, 100% Betula leaf litter, and a 50/50 mixture of both, in mesocosms for 406 days. We revealed the transfer of C from the litters to the soil invertebrate species by 13C labeling of each of the litter types and assessed 13C signatures of the invertebrates Collembola species composition differed significantly between Sphagnum and Betula litter. Within the 'single type litter' mesocosms, Collembola species showed different 13C signatures, implying species-specific differences in diet choice. Surprisingly, the species composition and Collembola abundance changed relatively little as a consequence of Betula input to a Sphagnum based system. Their diet choice, however, changed drastically; species-specific differences in diet choice disappeared and approximately 67% of the food ingested by all Collembola originated from Betula litter. Furthermore, litter decomposition patterns corresponded to these findings; mass loss of Betula increased from 16.1% to 26.2% when decomposing in combination with Sphagnum, while Sphagnum decomposed even slower in combination with Betula litter (1.9%) than alone (4.7%). This study is the first to empirically show that collective diet shifts of the peatland decomposer community from mosses towards vascular plant litter may drive altered decomposition patterns. In addition, we showed that

  19. 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

  20. Sphagnum can 'filter' N deposition, but effects on the plant and pore water depend on the N form.

    PubMed

    Chiwa, Masaaki; Sheppard, Lucy J; Leith, Ian D; Leeson, Sarah R; Tang, Y Sim; Cape, J Neil

    2016-07-15

    The ability of Sphagnum moss to efficiently intercept atmospheric nitrogen (N) has been assumed to be vulnerable to increased N deposition. However, the proposed critical load (20kgNha(-1)yr(-1)) to exceed the capacity of the Sphagnum N filter has not been confirmed. A long-term (11years) and realistic N manipulation on Whim bog was used to study the N filter function of Sphagnum (Sphagnum capillifolium) in response to increased wet N deposition. On this ombrotrophic peatland where ambient deposition was 8kgNha(-1)yr(-1), an additional 8, 24, and 56kgNha(-1)yr(-1) of either ammonium (NH4(+)) or nitrate (NO3(-)) has been applied for 11years. Nutrient status of Sphagnum and pore water quality from the Sphagnum layer were assessed. The N filter function of Sphagnum was still active up to 32kgNha(-1)yr(-1) even after 11years. N saturation of Sphagnum and subsequent increases in dissolved inorganic N (DIN) concentration in pore water occurred only for 56kgNha(-1)yr(-1) of NH4(+) addition. These results indicate that the Sphagnum N filter is more resilient to wet N deposition than previously inferred. However, functionality will be more compromised when NH4(+) dominates wet deposition for high inputs (56kgNha(-1)yr(-1)). The N filter function in response to NO3(-) uptake increased the concentration of dissolved organic N (DON) and associated organic anions in pore water. NH4(+) uptake increased the concentration of base cations and hydrogen ions in pore water though ion exchange. The resilience of the Sphagnum N filter can explain the reported small magnitude of species change in the Whim bog ecosystem exposed to wet N deposition. However, changes in the leaching substances, arising from the assimilation of NO3(-) and NH4(+), may lead to species change. PMID:27058130

  1. Peat deposits of North Carolina: Bulletin 88

    SciTech Connect

    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 a 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.

  2. Utilization of peat as a fuel

    SciTech Connect

    Clemens, D.F.; Evans, G.O. II; Whitehurst, B.M.

    1981-10-01

    This work has dealt primarily with the development and evaluation of peat/No. 2 fuel oil mixtures (POM) and peat/methanol mixtures (PAM). POM and PAM slurries with varied peat loadings, peat moisture contents, and peat particle sizes have been studied by measuring slurry sedimentation ratios in jacketed glass tubes and slurry drain times from the tubes along with the slurry viscosities. The peat moisture content was found to be especially critical in forming stable slurries. Also, in both the PAM and POM systems, it was found that use of the more finely ground peat led to significantly higher sedimentation ratios than the use of coarse peat. Numerous additives selected to improve slurry suspension and flow characteristics have been evaluated. Cab-O-Sil M-5 and Cab-O-Sil PTG were most effective in the POM systems while Attagel X-2059 and Bentone 27 were most effective in the PAM systems. Viscosities have been measured for slurries of varied particle size and modified by selected additives. Viscosities in the PAM system were lower using the coarser peat with higher moisture content while viscosities in the POM system seemed to be lower using the finer, drier peat. Calorimetric studies of powdered peat as well as PAM and POM slurries, with and without additives, were completed. Combustion tests of POM and PAM slurries were carried out using a salamander type shop heater. Successful burns of the POM slurry were accomplished when the slurries were heated to reduce viscosities and the peat was prescreened to remove large wood fibers to avoid plugging of the small burner nozzle. Since the toxicity and low flash point of methanol precluded heating of the PAM slurries, plugging of the small burner routinely occurred. It was also demonstrated that ground peat could be burned by using an eductor connector to a compressed air line.

  3. H2O and CO2 exchange between a sphagnum mire ecosystem and the atmosphere

    NASA Astrophysics Data System (ADS)

    Olchev, Alexander; Volkova, Elena; Karataeva, Tatiana; Novenko, Elena

    2013-04-01

    The modern climatic conditions are strongly influenced by both internal variability of climatic system, and various external natural and anthropogenic factors (IPCC 2007). Significant increase of concentration of greenhouse gases in the atmosphere and especially the growth of atmospheric CO2 due to human activity are considered as the main factors that are responsible for modern global warming and climate changes. A significant part of anthropogenic CO2 is absorbed from the atmosphere by land biota and especially by vegetation cover. However, it is still not completely clear what is the role of different land ecosystems and especially forests and mires in global cycles of H2O and CO2 and what is a sensitivity of these ecosystems to climate changes. Within the framework of this study the spatial and temporal variability of H2O and CO2 fluxes between a mire ecosystem and the atmosphere was described using results of the field measurements and modeling approach. For the study a mire ecosystem located in Tula region in European part of Russia was selected. The selected mire has karst origin, depth of peat float is 2.5-3.0 m (depth of depression is more than 10 meter), area is about 1 ha. The mire vegetation is characterized by sedge and sphagnum mosses cover. The mire is surrounded by broad-leaved forest of about 20 meter high. To describe the temporal and spatial patterns of H2O and CO2 fluxes within selected mire the chamber method was applied. The measurement were carried out along transect from mire edge to center from June to September of 2012. For measurements the transparent ventilated chambers combined with portable infrared CO2/H2O analyzer LI-840 (Li-Cor, USA) was used. To estimate the gross primary production and respiration of different type of vegetation within the mire the measurements were conducted both under actual light conditions and artificial shading. Results of the experimental studies showed that the maximal CO2 fluxes was observed in central

  4. PwC's 3-Peat

    ERIC Educational Resources Information Center

    Freifeld, Lorri

    2010-01-01

    PricewaterhouseCoopers (PwC) is giving the Chicago Bulls a run for their money when it comes to three-peats. The professional services firm scored the top spot on the Training Top 125 for a record third year in a row. So, just how did PwC nail No. 1 again? For starters, it met and exceeded a hefty challenge in fiscal year 2009: cutting training…

  5. Lake or bog? Reconstructing baseline ecological conditions for the protected Galápagos Sphagnum peatbogs

    NASA Astrophysics Data System (ADS)

    Coffey, Emily E. D.; Froyd, Cynthia A.; Willis, Katherine J.

    2012-10-01

    This paper documents the first 10,000 year old plant macrofossil record of vegetation changes on the central island of Santa Cruz, providing information on Sphagnum bog vegetation patterns, local extinction of key taxa, and temporal successions in the Galápagos humid highlands. Vegetation change is reconstructed through examination of Holocene sedimentary sequences obtained from three Sphagnum bogs located within volcanic caldera forming the high elevation central ridge system of Santa Cruz Island. Results indicate that these specialized Sphagnum bog ecosystems are dynamic and have undergone considerable changes in vegetation composition, transitioning from diverse hygrophilous herbs and submerged aquatic ecosystems to drier Sphagnum/Pteridium bog systems, during the last 10,000 cal yr BP. Additionally a new aquatic genus previously undocumented on the islands, Elatine, was discovered at two of the study sites, but it is now extinct on the archipelago. Some of the observed vegetation successions may have been driven by climatic shifts occurring within the eastern equatorial Pacific (EEP). Other drivers including anthropogenic change are also considered significant over the last hundred years, placing strain on this naturally dynamic system. This study helps reveal patterns of change in the humid highlands over the last 10,000 cal yr BP regarding vegetation variability, climatic shifts, the historical influence of fire, tortoise disturbance, and recent anthropogenic impacts on the island.

  6. Vertical transmission explains the specific Burkholderia pattern in Sphagnum mosses at multi-geographic scale

    PubMed Central

    Bragina, Anastasia; Cardinale, Massimiliano; Berg, Christian; Berg, Gabriele

    2013-01-01

    The betaproteobacterial genus Burkholderia is known for its versatile interactions with its hosts that can range from beneficial to pathogenic. A plant-beneficial-environmental (PBE) Burkholderia cluster was recently separated from the pathogen cluster, yet still little is known about burkholderial diversity, distribution, colonization, and transmission patterns on plants. In our study, we applied a combination of high-throughput molecular and microscopic methods to examine the aforementioned factors for Burkholderia communities associated with Sphagnum mosses – model plants for long-term associations – in Austrian and Russian bogs. Analysis of 16S rRNA gene amplicons libraries revealed that most of the Burkholderia are part of the PBE group, but a minor fraction was closely related to B. glathei and B. andropogonis from the pathogen cluster. Notably, Burkholderia showed highly similar composition patterns for each moss species independent of the geographic region, and Burkholderia-specific fluorescent in situ hybridization of Sphagnum gametophytes exhibited similar colonization patterns in different Sphagnum species at multi-geographic scales. To explain these patterns, we compared the compositions of the surrounding water, gametophyte-, and sporophyte-associated microbiome at genus level and discovered that Burkholderia were present in the Sphagnum sporophyte and gametophyte, but were absent in the flark water. Therefore, Burkholderia is a part of the core microbiome transmitted from the moss sporophyte to the gametophyte. This suggests a vertical transmission of Burkholderia strains, and thus underlines their importance for the plants themselves. PMID:24391630

  7. Freshwater peat on the continental shelf

    USGS Publications Warehouse

    Emery, K.O.; Wigley, R.L.; Bartlett, A.S.; Rubin, M.; Barghoorn, E.S.

    1967-01-01

    Freshwater peats from the continental shelf off northeastern United States contain the same general pollen sequence as peats from ponds that are above sea level and that are of comparable radiocarbon ages. These peats indicate that during glacial times of low sea level terrestrial vegetation covered the region that is now the continental shelf in an unbroken extension from the adjacent land areas to the north and west.

  8. Freshwater peat on the continental shelf.

    PubMed

    Emery, K O; Wigley, R L; Bartlett, A S; Rubin, M; Barghoorn, E S

    1967-12-01

    Freshwater peats from the continental shelf off northeastern United States contain the same general pollen sequence as peats from ponds that are above sea level and that are of comparable radiocarbon ages. These peats indicate that during glacial times of low sea level terrestrial vegetation covered the region that is now the continental shelf in an unbroken extension from the adjacent land areas to the north and west. PMID:17801856

  9. Biosorption of Metallic Elements onto Fen Peat

    NASA Astrophysics Data System (ADS)

    Krumins, Janis; Robalds, Artis

    2014-12-01

    Industrial development and anthropogenic activity have a huge impact on the environment, forcing society to find new and cost-effective environment treatment technologies. One of the most effective and environmentally friendly methods is the use of biosorbents, for which peat is one of the most cost-effective materials. The adsorption capabilities of peat sediments are well known; however, mainly raised bog peat is used for environmental treatment, and thus the abilities of fen peat are underestimated. The aim of this research was to assess the fen peat suitability as an adsorbent for metallic elements. In this study we have determined the sorption characteristics of Ca, Mg, K, Na, Cu and Pb and results show that fen peat deposits have a huge variability as a biosorbent due to their variable botanical composition and complex properties, for instance, under equal conditions, wood-sedge peat can have higher lead adsorption capacity than wood peat. However, due to its natural content of metallic elements, the sorption capacity overall is lower than it is for raised bog peat, although the high pH reaction encourage a high mobility metals.

  10. Distribution of cell wall components in Sphagnum hyaline cells and in liverwort and hornwort elaters.

    PubMed

    Kremer, Celeste; Pettolino, Filomena; Bacic, Antony; Drinnan, Andrew

    2004-10-01

    Spiral secondary walls are found in hyaline cells of Sphagnum, in the elaters of most liverworts, and in elaters of the hornwort Megaceros. Recent studies on these cells suggest that cytoskeletal and ultrastructural processes involved in cell differentiation and secondary wall formation are similar in bryophytes and vascular plant tracheary elements. To examine differences in wall structure, primary and secondary wall constituents of the hyaline cells of Sphagnum novo-zelandicum and elaters of the liverwort Radula buccinifera and the hornwort Megaceros gracilis were analyzed by immunohistochemical and chemical methods. Anti-arabinogalactan-protein antibodies, JIM8 and JIM13, labeled the central fibrillar secondary wall layer of Megaceros elaters and the walls of Sphagnum leaf cells, but did not label the walls of Radula elaters. The CCRC-M7 antibody, which detects an arabinosylated (1-->6)-linked beta-galactan epitope, exclusively labeled hyaline cells in Sphagnum leaves and the secondary walls of Radula elaters. Anti-pectin antibodies, LM5 and JIM5, labeled the primary wall in Megaceros elaters. LM5 also labeled the central layer of the secondary wall but only during formation. In Radula elaters, JIM5 and another anti-pectin antibody, JIM7, labeled the primary wall. The distribution of arabinogalactan-proteins and pectic polysaccharides restricted to specific wall types and stages of development provides evidence for the developmental and functional regulation of cell wall composition in bryophytes. Monosaccharide-linkage analysis of Sphagnum leaf cell walls suggests they contain polysaccharides similar to those of higher plants. The most abundant linkage was 4-Glc, typical of cellulose, but there was also evidence for xyloglucans, 4-linked mannans, 4-linked xylans and rhamnogalacturonan-type polysaccharides. PMID:15290291

  11. A 2000-yr record of the extent of decomposition and vegetation change in peats from the Western Siberian Lowland as revealed from carbohydrate, lignin and amino acid analyses

    NASA Astrophysics Data System (ADS)

    Benner, R. H.; Kaiser, K.; Philben, M. J.; Beilman, D.; MacDonald, G. M.

    2011-12-01

    The Western Siberian Lowland is among the largest wetlands in the world, and it is estimated to store ~70 Pg C as peat. Based on radiocarbon dating, peat accumulation rates at sites south of 60°N are higher than those at more northerly sites during the past 2000 yr. The biochemical composition of peat from high-resolution sampling in four cores was analyzed to investigate the influence of current and past climatic events on the decomposition and diagenetic alteration of the accumulated peat. The analyzed cores were collected from 56.8°N (SIB04), 58.4°N (SIB06), 63.8°N (G137) and 66.5°N (E113). Molecular analyses of hydrolysable neutral sugars, amino acids and lignin phenols accounted for about 36% of the C and 50% of the N in the peat samples, indicating the observed compositional trends are generally representative of bulk C and N dynamics. Prominent compositional anomalies were observed in the upper 6-43 cm of SIB04, the most southern core. An 8-fold decline in Sphagnum-derived p-hydroxy phenols was accompanied by a 5-fold increase in gymnosperm-derived vanillyl phenols in the upper SIB04 core, indicating a shift in vegetation that was also observed at 5 other depths in the core. The yield of neutral sugars decreased from 27% to 10% of total C in peat deposited over a span of about 230 yr. The C/N ratio declined from 68 to 45, and the yield of amino acids increased two-fold. These changes indicate extensive decomposition of the surface (6-9 cm) peat occurred during the last few decades, a period of significant warming in the region. We estimate a 50-65% mass loss in surface peat at the SIB04 site. No apparent indication of extensive decomposition was observed in surface peat at the SIB06 site located 2° further north. About 33% of total C was accounted for in neutral sugars, the C/N ratio was above 100 and amino acid yields were relatively low. A 2-fold increase in vanillyl and syringyl phenols indicates the input of angiosperm vegetation in the upper SIB06

  12. Finding of probable Tunguska Cosmic Body material: anomalies in platinum group elements in peat from the explosion area

    NASA Astrophysics Data System (ADS)

    Kolesnikov, E. M.; Hou, Q. L.; Xie, L. W.; Kolesnikova, N. V.

    2005-04-01

    Further evidencies of a cometary nature of the 1908 Tunguska Cosmic Body (TCB) are presented. Earlier in the event layers of the Sphagnum fuscum peat from the explosion area, anomalies, relative to Earth-materials, of the elements H, C, and N—all abundant in comets—have been found [E.W. Kolesnikov, T. Boettger and N.V. Kolesnikova, Planet. Space Sci. 47 905 (1999); E.M. Kolesnikov, G. Longo, T. Boettger, N.V. Kolesnikova, P. Gioacchini, L. Forlani, R. Giampieri and R. Serra, Icarus 161 235 (2003).]. At the present work we revealed a sharp increase of concentrations of platinum group elements (PGE), REE and other elements in the event layers as well. Their ratios point to a cometary nature of the anomalies observed.

  13. 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

  14. Water movement through blanket peat is dominated by a complicated pattern of near-surface flows

    NASA Astrophysics Data System (ADS)

    Turner, Ed; Baird, Andy; Billett, Mike; Chapman, Pippa; Dinsmore, Kerry; Holden, Joseph

    2015-04-01

    Blanket peatland formation and functioning depend strongly on hydrology. Omitting the potential for pipe flow, the acrotelm-catotelm model is still widely held to apply to blanket peatlands. In the model, water flow through the peat profile is dominated by near-surface flow in the acrotelm, whereas water movement below the level of (near) permanent saturation (the catotelm) is characterised by very low hydraulic conductivity (K). Whilst some work has been done on characterising Kat different depths in blanket peatlands, very little is known about near-surface K, particularly with respect to how it varies between microforms and over fine spatial scales. We undertook a detailed investigation of near-surface (0 - 12 cm) and deeper (30 and 50 cm) K at a blanket peatland site in the Flow Country in Scotland (UK). Near-surface Kof peat samples taken across a range of microforms was measured vertically (Kv) and horizontally (Kh) in the laboratory using a new 'split cylinder' method (n = 48 excluding repeat tests). K30 (n = 20) andK50 (n = 20) were estimated in situ using the piezometer or seepage-tube method. To help our interpretation of the near-surface K measurements we recorded the vegetation cover from where the peat samples were taken and characterised each peat sample in terms of its plant macrofossil assemblage and dry bulk density. We found that Kvand Khwere highly variable between microforms in the near-surface samples, ranging over two orders of magnitude (0.489 - 0.003 cm s-1). Kernel density plots show that Kvwas most commonly in the region of ~0.03 cm s-1 at 0 - 6 cm, and ~0.015 cm s-1 at 6 - 12 cm, whereas Kh was ~0.05 and ~0.001 cm s-1 respectively. These data reveal a high degree of absolute variability and anisotropy in K over small scales. The deeper K30and K50 values were typically an order of magnitude or more lower than the near-surface K, and were less variable between test locations with the exception of poorly humified Sphagnum-dominated peat

  15. Peat hydraulic conductivity in different landuses

    NASA Astrophysics Data System (ADS)

    Mustamo, Pirkko; Hyvärinen, Maarit; Ronkanen, Anna-Kaisa; Kløve, Bjørn

    2013-04-01

    Information on hydraulic conductivity and water retention properties of peatlands is needed, e.g., for modelling hydrology and soil carbon balance of peat soils. Ability to model the behaviour of peat soils, especially those drained for agricultural use, is important as cultivated peatlands act as a major source of CO2 and N2O emissions in Nordic countries. Peat soil hydraulic conductivity and water retention properties vary greatly, and their relationship to soil depth and degree of decomposition is not straightforward. The aim of this study was to produce new information about peat physical properties in different land uses and the relationship between peat soil hydraulic conductivity and variables such as soil porosity and degree of humification. Peat hydraulic conductivity was measured in situ with infiltrometer (direct push piezometer) in six study sites (two pristine bogs, two sites drained for forestry, a cultivated peat land site and a peat extraction site). Measurements were made in several depths according to soil profile. To examine relationship of soil properties and the hydraulic conductivity, undisturbed peat cores of known volume and also disturbed peat samples were collected from the study sites for determination of von Post humification factor, ash content, porosity and bulk density. Surface layer of the agricultural site had high ash content and bulk density and low porosity compared to the soil beneath it and the soil in other study sites. This was due to added sand and compaction by agricultural practice. Bog, in contrast, had very low bulk density and high porosity. Results show a great variation in hydraulic conductivity within the study sites even when the observations were in the same soil layer. Hydraulic conductivity was lowest in the peat extraction site and the agricultural site, and had higher correlation with study site (= landuse) and the measured layer than with soil porosity.

  16. Mineral resource of the month: peat

    USGS Publications Warehouse

    Jasinski, Stephen M.

    2008-01-01

    Peat is a natural organic material of botanical origin, harvested from deposits in bogs and fens. Commercial deposits form from the incomplete decomposition of plant matter under anaerobic conditions and gradually accumulate to form peat over about a 5,000-year period.

  17. Small scale controls of greenhouse gas release under elevated N deposition rates in a restoring peat bog in NW Germany

    NASA Astrophysics Data System (ADS)

    Glatzel, S.; Forbrich, I.; Krüger, C.; Lemke, S.; Gerold, G.

    2008-06-01

    In Central Europe, most bogs have a history of drainage and many of them are currently being restored. Success of restoration as well as greenhouse gas exchange of these bogs is influenced by environmental stress factors as drought and atmospheric nitrogen deposition. We determined the methane and nitrous oxide exchange of sites in the strongly decomposed center and less decomposed edge of the Pietzmoor bog in NW Germany in 2004. Also, we examined the methane and nitrous oxide exchange of mesocosms from the center and edge before, during, and following a drainage experiment as well as carbon dioxide release from disturbed unfertilized and nitrogen fertilized surface peat. In the field, methane fluxes ranged from 0 to 3.8 mg m-2 h-1 and were highest from hollows. Field nitrous oxide fluxes ranged from 0 to 574 μg m-2 h-1 and were elevated at the edge. A large Eriophorum vaginatum tussock showed decreasing nitrous oxide release as the season progressed. Drainage of mesocosms decreased methane release to 0, even during rewetting. There was a tendency for a decrease of nitrous oxide release during drainage and for an increase in nitrous oxide release during rewetting. Nitrogen fertilization did not increase decomposition of surface peat. Our examinations suggest a competition between vascular vegetation and denitrifiers for excess nitrogen. We also provide evidence that the von Post humification index can be used to explain nitrous oxide release from bogs, if the role of vascular vegetation is also considered. An assessment of the greenhouse gas release from nitrogen saturated restoring bogs needs to take into account elevated release from fresh Sphagnum peat as well as from sedges growing on decomposed peat. Given the high atmospheric nitrogen deposition, restoration will not be able to achieve an oligotrophic ecosystem in the short term.

  18. 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

  19. Nitrogen dynamics in peat bogs: Comparison of sites with contrasting pollution levels (Central Europe)

    NASA Astrophysics Data System (ADS)

    Novak, Martin; Bohdalkova, Leona; Stepanova, Marketa; Vile, Melanie A.; Wieder, Kelman R.

    2013-04-01

    Nitrogen belongs to chemical elements whose biogeochemical cycles are most heavily disturbed by human activities, and large regions worlwide experience elevated depositions of reactive N (NO3-, NH4+). Peatlands contain as much as 15 % of the world's soil N. It it is unclear whether fertilizing by anthopogenic N will lead to higher storage of C in wetlands. Elevated N input may lead to both higher net primary productivity, but will also augment microbial decomposition. Here we discuss two aspects of N cycling in Sphagnum-dominated bogs in the Czech Republic, an area characterized by a steep north-south pollution gradient and high annual N deposition (60 kg ha-1). These two aspects are N inventory in 210Pb-dated peat cores, and post-depositional mobility of N in peat. We compared the N inventory in two Czech bogs, differing in pollution, with cumulative atmospheric N input. We hypothesized that the total amount of N in the peat cores would be smaller than the cumulative N input (leaching of excess N from the bog, denitrification). The two bogs were VJ (industrial north) and CB (rural south). The investigated period was 1885-2002. The total amount of N was 4020 kg ha-1 at VJ and 1530 kg ha-1 at CB. Peat in the north contained 2.6 times more N than in the south. Historical rates of N deposition in the Czech Republic are well known (numerous papers by Kopacek). To estimate cumulative N inputs into the bogs, we also used the monthly N depositions between 1994 and 2002, measured in two nearby catchments. The estimated cumulative atmospheric N input was 1350 kg ha-1 at VJ, and 530 kg ha-1 at CB. In both cases, the amount of N found in peat was 3 times higher than the estimated atmospheric N input. Such high storage of N in peat is surprising. Post-depositional mobility of N may help to explain the discrepancies between atmospheric N inputs and N storage in peat. We found two-fold evidence for post-depositional mobility of N. Maximum N concentrations at VJ were observed in

  20. [Effect of mechanical grinding of Sphagnum on the structure and physiological state of bacterial communities].

    PubMed

    Dobrovol'skaya, T G; Golovchenko, A V; Yakushev, A V; Manucharova, N A; Yurchenko, E N

    2014-01-01

    The microcosm method was used to demonstrate an increase in bacterial numbers and drastic changes in the taxonomic structure of saprotrophic bacteria as a result of mechanical grinding of Sphagnum moss. Ekkrisotrophic agrobacteria predominant in untreated moss were replaced by hydrolytic bacteria. Molecular biological approaches revealed such specific hydrolytic bacteria as Janthinobacterium agaricum and Streptomyces purpurascens among the dominant taxa. The application of kinetic technique for determination of the physiological state of bacteria in situ revealed higher functional diversity of hydrolytic bacteria in ground moss than in untreated samples. A considerable decrease of the C/N ratio in ground samples of living Sphagnum incubated using the microcosm technique indicated decomposition of this substrate. PMID:25941721

  1. An evaluation of phenylpropanoid metabolism during cold-induced sphagnorubin synthesis in Sphagnum magellanicum BRID.

    PubMed

    Tutschek, R

    1982-08-01

    L-phenylalanine ammonia-lyase (PAL; EC 4.3.1.5) from Sphagnum magellanicum BRID. is inhibited by t-cinnamic acid in vitro only at relatively high doses. In contrast, p-coumaric acid does not display an inhibitory effect in a comparable concentration range. Sphagnum acid, an endogenous cinnamic acid derivative of sphagna, strongly enhances PAL activity at certain concentrations. The involvement of the phenylpropanoid pathway in the biosynthesis of the main reddish-violet wall pigment of Sphagnum magellanicum (sphagnorubin) is studied at several metabolic levels. Extractable PAL activity rises in response to the stimulus of sphagnorubin synthesis (nightly application of low temperature). If the formation of sphagnorubin is blocked in vivo by the PAL-inhibitor L-α-aminooxy-β-phenylpropionic acid (AOPP), complementation of the mosses by p-coumaric acid is able to overcome partially the inhibition. The mechanism of PAL induction by nightly cold treatment is independent of soluble carbohydrates which concomitantly accumulate as a result of photosynthetic action. Suppression of the sugar formation by application of 3-(3,4-dichlorophenyl)-1,1-dimethyl urea (DCMU) is contrasted with an enhancement of PAL activity above the level of the merely cold-treated plants. The fluctuations of the enzyme level are principally unaffected by a DCMU-treatment. PMID:24271863

  2. Peat Hydrolysate Medium Optimization for Pullulan Production

    PubMed Central

    Boa, Jacques M.; LeDuy, Anh

    1984-01-01

    Peat hydrolysate, a diluted acid-autoclaved extract of peat, was used as a substrate for the production of the extracellular polysaccharide pullulan by three strains of Aureobasidium pullulans, 140B, 142, and 2552. It was found that the addition of (NH4)2SO4 and K2HPO4 as sources of nitrogen and phosphate, respectively, is not necessary for the polysaccharide production. The economically optimized culture medium for large-scale production of pullulan contains peat hydrolysate, 0.05% NaCl, 0.02% MgSO4, and 0.01% antifoam FG-10. The initial pH of peat hydrolysate medium is adjusted to its optimum value of 6.0 with Ca(OH)2. The total ingredient cost for the production of each kilogram of pullulan with optimized medium is only 1/10 of that with the nonoptimized medium. In this study, a zero cost for peat hydrolysate was assumed, since it is an effluent of the peat and peat processing industries. PMID:16346596

  3. Evaluating approaches for estimating peat depth

    NASA Astrophysics Data System (ADS)

    Parry, L. E.; West, L. J.; Holden, J.; Chapman, P. J.

    2014-04-01

    Estimates of peat depth are required to inform understanding of peatland development, functioning, and ecosystem services such as carbon storage. However, there is a considerable lack of peat depth data at local, national, and global scales. Recent studies have attempted to address this knowledge deficit by using manual probing and ground-penetrating radar (GPR) to estimate depth. Despite increasing application, little consideration has been given to the accuracy of either of these techniques. This study examines the accuracy of probing and GPR for measuring peat depth. Corresponding GPR and probing surveys were carried out at a catchment scale in a blanket peatland. GPR depth estimations, calibrated using common midpoint (CMP) surveys, were found to be on average 35% greater than probe measurements. The source of disagreement was found to be predominantly caused by depth probes becoming obstructed by artifacts within the peat body, although occasionally probing rods also penetrated sediments underlying the peat. Using the Complex Refractive Index Model, it was found that applying a single velocity of 0.036 m ns-1 across a single site may also result in -8 to +17% error in estimation of peat depth due to spatial variability in water content and porosity. It is suggested that GPR calibrated at each site using CMP surveys may provide a more accurate method for measuring peat depth.

  4. Evaluation of peat as a utility boiler fuel. Final report

    SciTech Connect

    Bongiorno, S.J.; Strianse, R.V.

    1983-03-01

    The objective of this study was to assess the technical and economic feasibility of the direct combustion of peat for electric power generation in the United States. The study includes a review of peat literature, selection of a region in the US to locate a hypothetical peat-harvesting operation, and an assessment of current practices for peat utilization in Europe, including peat harvesting, environmental control, and combustion technology. The conceptual design of a peat-harvesting facility supplying 1.4 million tons/yr of peat to a 2 x 150 MW power plant located in eastern North Carolina is developed for the purpose of estimating peat fuel costs. Environmental-control measures and peat transportation systems are identified. Budget capital and operating costs for a peat-fired power plant are estimated and the busbar cost of electricity compared to that for a 1 x 300 MW coal-fired power plant. Technical feasibility is demonstrated, although environmental acceptability of a large-scale peat harvesting operation must be confirmed on a site-specific basis. Peat fuel costs are found to be less than coal costs for a power plant located adjacent to the peat bogs in eastern North Carolina. The higher capital cost of a peat-fired power plant offsets to some extent the fuel cost advantage. Peat is found to have an electricity cost advantage of about 5 to 25% when compared to coal on a 30 year levelized basis depending on the peat escalation rate assumed.

  5. HYDRAULIC CONDUCTIVITY OF ESSENTIALLY SATURATED PEAT

    SciTech Connect

    Nichols, R

    2008-02-27

    The Savannah River National Laboratory measured the hydraulic conductivity of peat samples using method ASTM D4511-00. Four samples of peat were packed into 73mm diameter plastic tubes and saturated from the bottom up with water. The columns were packed with Premier ProMoss III TBK peat to a dry density of approximately 0.16 gm/cc (10 lb/ft3). One column was packed using oven dried peat and the other 3 were packed using as delivered peat. The oven dried sample was the most difficult to saturate. All of the peat samples expanded during saturation resulting in a sample length (L) that was longer than when the sample was initially packed. Table 1 contains information related to the column packing. After saturation the hydraulic conductivity test was conducted using the apparatus shown in Figure 1. Three of the samples were tested at 2 different flow conductions, 1 high and 1 low. Table 2 and Figure 2 contain the results of the hydraulic conductivity testing. Each test was run for a minimum of 40 minutes to allow the test conditions to stabilize. The hydraulic conductivity at the end of each test is reported as the hydraulic conductivity for that test. The hydraulic conductivity of the 4 peat samples is 0.0052 {+-} 0.0009 cm/sec. This result compares well with the hydraulic conductivity measured in the pilot scale peat bed after approximately 2 months of operation. The similarity in results between the dry pack sample and moist pack samples shows the moisture content at the time of packing had a minimal effect on the hydraulic conductivity. Additionally, similarity between the results shows the test is reproducible. The hydraulic conductivity results are similar to those reported by other tests of peat samples reported in the literature.

  6. Biogasification of pretreated Reed Sedge peat

    SciTech Connect

    Ghosh, S.

    1980-01-01

    The anaerobic digestion characteristics of acid treated Reed Sedge peat under mesophilic and thermophilic conditions are described. The effect of acid treatment on methane production from peat is discussed. Types of nutrients used include sewage sludge. Chemical characteristics indicate that anaerobic digestion of peat could be deficient in phosphorus, sodium, potassium, and magnesium. Acid hydrolysis increased gas production and volatile acids. Thermophilic conditions resulted in higher gas and methane yields. Addition of large quantitites of sewage sludge greatly improved methane yield. Diluted digested slurries can be dewatered by vacuum filtration and mechanical pressing into cakes (34% wt solids). (DMC)

  7. Trace element content of northern Ontario peat

    SciTech Connect

    Glooschenko, W.A.; Capoblanco, J.A.

    1982-03-01

    Peat samples were collected at 0-20- and 20-40-cm depths from several peatland ecosystems located in northern Ontario, Canada. Analysis was made for the trace metals Zn, Pb, Cu, Cr, Cd, and Hg. Concentration values in general were in the low ppm range and did not significantly differ in terms of peatland type or depth except for Pb. This element was signficantly higher in surface peats in bogs and fens. Concentration of metals in peats found in the study were equivalent to those in US coals, suggesting caution during combustion in terms of potential atmospheric input of metals.

  8. Peat humic acids and their complex forming properties as influenced by peat humification

    NASA Astrophysics Data System (ADS)

    Dudare, D.; Klavins, M.

    2012-04-01

    To study paleoenvironmental changes of importance is understanding of processes of organic matter diagenesis, especially changes of refractory part of natural organic substances - humic substances. Studies of the living organic matter humification process are also essential for understanding of the carbon biogeochemical cycle. The aim of this study was to analyze peat organic matter diagenesis: changes of properties of humic acids, relations between the humification process, properties of peat, peat humic acids, their ability to interact with metal ions, as well ability to accumulate metals. The analysis were carried out on samples of humic substances preparatively extracted from three ombrotrophic bog peat profiles to identify the links between peat age, decomposition and humification degree, botanical composition and properties of peat humic acids elemental (C, H, N, O), functional (-COOH, -OH) composition, structural characteristics - UV, fluorescence, FTIR. The found variability of peat properties is less significant than differences in the properties of peat-forming living matter, thus revealing the dominant impact of humification process on the properties of peat. Correspondingly, composition of peat humic acids is little affected by differences in the properties of precursor living organic material, and such indicators as decomposition degree, humification degree, humic acid elemental ratio and concentrations of acidic functional groups are the best descriptors of changes in organic matter during the process of organic matter diagenesis and humification. Peat ability to accumulate major and trace elements depends on the character of element supply, potency of metal ions to bind functionalities in the peat, with an emphasis on the structure of peat humic acid, pH reaction, oxygen presence, presence of complexing compounds, inorganic ions and many other factors. Major and trace element presence in peat is of importance as an indicator of peat genesis and

  9. Peat deposits of the Carolina Bays of North Carolina

    SciTech Connect

    Ingram, R.L.; Otte, L.J.; Witner, T.W.

    1983-11-01

    Of the approximately 500 Carolina Bays larger than 100 acres (3,000 ft. long) in the Coastal Plain of North Carolina, 96 contained at least 1 ft of peat. The 96 bays have a total of 35,000 acres of peatland containing 15 millions tons of moisture-free peat. Of these 96 bays, 43 have peat greater than 4 ft thick totaling 8,000 acres with 8 million tons of peat. The largest single deposit of peat greater than 4 ft thick contains 1.1 million tons in a 1,000 acre area. Two main types of peat are present: (1) a black, fine-grained, highly decomposed peat, and (2) a brownish, decomposed somewhat fibrous peat usually found at the base of the thicker peats. An average peat has 84% moisture, 6% ash, 0.2% sulfur, and a heating value of 10,000 Btu/lb.

  10. 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

  11. 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.

  12. Laboratory simulation of the successive aerobic and anaerobic degradation of oil products in oil-contaminated high-moor peat

    NASA Astrophysics Data System (ADS)

    Tolpeshta, I. I.; Trofimov, S. Ya.; Erkenova, M. I.; Sokolova, T. A.; Stepanov, A. L.; Lysak, L. V.; Lobanenkov, A. M.

    2015-03-01

    A model experiment has been performed on the successive aerobic and anaerobic degradation of oil products in samples of oil-contaminated peat sampled from a pine-subshrub-sphagnum bog near the Sutormin oilfield pipeline in the Yamal-Nenets autonomous district. During the incubation of oil-contaminated peat with lime and mineral fertilizers under complete flooding, favorable conditions are created for the aerobic oxidation of oil products at the beginning of the experiment and, as the redox potential decreases, for the anaerobic degradation of oil products conjugated with the reduction of N5+ and S+6 and methanogenesis. From the experimental data on the dynamics of the pH; Eh; and the NO{3/-}, NO{2/-}, and SO{4/2-} concentrations in the liquid phase of the samples, it has been found that denitrifiers significantly contributed to the biodegradation of oil products under the experimental conditions. After the end of the experiment, the content of oil products in the contaminated samples decreased by 21-26%.

  13. A Holocene record of climate, vegetation change and peat bog development, east Otago, South Island, New Zealand

    NASA Astrophysics Data System (ADS)

    McGlone, Matt S.; Wilmshurst, Janet M.

    1999-05-01

    A Holocene record of pollen, macrofossils, testate amoebae and peat humification is presented from a small montane bog. Sediment accumulation began before 9000 yr BP, but peat growth not until ca. 7000 BP. From 12 000 to 7000 yr BP, a shrub-grassland dominated under a dry climate, with increasing conifer forest and tall scrub from ca. 9600 yr BP. At 7000 yr BP a dense montane-subalpine low conifer forest established under a moist, cool climatic regime. Between 7000 and 700 yr BP the bog surface was shrubby, tending to be dry but with highly variable surface wetness. The catchment was affected by major fire at least four times between 4000 and 1000 yr BP. Both fire and bog surface wetness may have been linked to ENSO-caused variations in rainfall. Cooler, cloudier winters and disturbance by fire promoted the expansion of the broadleaf tree Nothofagus menziesii between 4000 yr BP and 1300 yr BP at the expense of the previous conifer forest-scrub vegetation. Polynesian fires (ca. 700 yr BP) reduced the vegetation to tussock grassland and bracken. Deforestation did not markedly affect the hydrology of the site. European pastoralism since ad 1860 has increased run-off and rising water tables in the bog have led to a Sphagnum-dominated cover.

  14. Ebullition of biogenic gas bubbles from samples of near-surface peat.

    NASA Astrophysics Data System (ADS)

    Baird, A.; Waldron, S.

    2004-05-01

    that it appeared to match gas production. The amount of ebullition varied substantially between samples. In two samples from the Scottish bog consisting respectively of Sphagnum papillosum and S. magellanicum litter, over 400 ml of gas per sample was lost over a 90-day period. At the other extreme, virtually no ebullition occurred from one of the Welsh peat samples, with only 14.5 ml being lost in 125 days. Provisional calculations based on CH4 concentrations in our gas permeation samplers suggest that CH4 efflux from the peatland surface via ebullition is potentially as important as that via diffusional transfer. We consider how transportable our data are to field conditions.

  15. NH4NO3 fertilizer induces DON leaching from Sphagnum magellanicum

    NASA Astrophysics Data System (ADS)

    Hartsock, J. A.; Vile, M. A.; Wieder, R.

    2011-12-01

    Boreal peatlands globally function as long-term sinks for atmosheric CO2. Mosses in the genus Sphagnum dominate the understory of boreal peatlands, especially in ombrotrophic bogs for which the sole sources of new nitrogen (N) is atmospheric deposition and biological N2-fixation. Sphagnum mosses in undisturbed regions generally are thought to be N-limited because of slow nutrient turnover and low rates of atmospheric N deposition. In Alberta, Canada, mean background N deposition rates are less than 1 kg N ha-1yr-1, but increasing atmospheric N deposition is occurring as a consequence of oil sands development in northern Alberta. In some European countries, anthropogenic practices have increased annual N deposition rates to levels in excess of 20 kg N ha-1yr-1. Increased rates of atmospheric N deposition have been shown to alter N cycling processes of Sphagnum mosses. Current hypotheses propose that Sphagnum mosses leach dissolved organic nitrogen (DON) from their tissues to mitigate N saturation stress in high N deposition areas. The goal of this study was to determine whether Sphagnum magellanicum leaches DON when exposed to elevated concentrations of NH4NO3 applied experimentally as synthetic rainfall. Sphagnum magellanicum was collected from a fen in Driftwood, Pennsylvania (41°13'58"N 78°11'44"W). Intact cores (10.5cm x 5.5cm) were grown in 500 mL culture flasks in a controlled environment chamber at Villanova University. Ammonium nitrate was applied to moss treatments eight times over 73 days at concentrations equivalent to 6 kg N ha-1yr-1, 12 kg N ha-1yr-1, and 18 kg N ha-1yr-1 (n=5 replicates per treatment, 400 mL H2O per N addition). Leachates (freely drained water samples) were analyzed for dissolved total nitrogen (TN), ammonium (NH4+-N), nitrate (NO3--N), and DON (TN-DIN) concentrations. Results show that after 73 days, increasing DIN resulted in: 1) a shift from net N mineralization to net NH4+ immobilization (Control: 376.3 ± 15.2 ug/g; High N: -377

  16. The effect of pore structure on ebullition from peat

    NASA Astrophysics Data System (ADS)

    Ramirez, Jorge A.; Baird, Andy J.; Coulthard, Tom J.

    2016-06-01

    The controls on methane (CH4) bubbling (ebullition) from peatlands are uncertain, but evidence suggests that physical factors related to gas transport and storage within the peat matrix are important. Variability in peat pore size and the permeability of layers within peat can produce ebullition that ranges from steady to erratic in time and can affect the degree to which CH4 bubbles bypass consumption by methanotrophic bacteria and enter the atmosphere. Here we investigate the role of peat structure on ebullition in structurally different peats using a physical model that replicates bubble production using air injection into peat. We find that the frequency distributions of number of ebullition events per time and the magnitude of bubble loss from the physical model were similar in shape to ebullition from peatlands and incubated peats. This indicates that the physical model could be a valid proxy for naturally occurring ebullition from peat. For the first time, data on bubble sizes from peat were collected to conceptualize ebullition, and we find that peat structure affects bubble sizes. Using a new method to measure peat macrostructure, we collected evidence that supports the hypothesis that structural differences in peat determine if bubble release is steady or erratic and extreme. Collected pore size data suggest that erratic ebullition occurs when large amounts of gas stored at depth easily move through shallower layers of open peat. In contrast, steady ebullition occurs when dense shallower layers of peat regulate the flow of gas emitted from peat.

  17. Radioactivity of peat mud used in therapy.

    PubMed

    Karpińska, Maria; Mnich, Krystian; Kapała, Jacek; Bielawska, Agnieszka; Kulesza, Grzegorz; Mnich, Stanisław

    2016-02-01

    The aim of the study was to determine the contents of natural and artificial isotopes in peat mud and to estimate the radiation dose absorbed via skin in patients during standard peat mud treatment. The analysis included 37 samples collected from 8 spas in Poland. The measurements of isotope concentration activity were conducted with the use of gamma spectrometry methods. The skin dose in a standard peat mud bath therapy is approximately 300 nSv. The effective dose of such therapy is considered to be 22 nSv. The doses absorbed during peat mud therapy are 5 orders of magnitude lower than effective annual dose absorbed from the natural radiation background by a statistical Pole (3.5 mSv). Neither therapeutic nor harmful effect is probable in case of such a small dose of ionising radiation. PMID:26675542

  18. Drainage and land use impacts on changes in selected peat properties and peat degradation in West Kalimantan Province, Indonesia

    NASA Astrophysics Data System (ADS)

    Anshari, G. Z.; Afifudin, M.; Nuriman, M.; Gusmayanti, E.; Arianie, L.; Susana, R.; Nusantara, R. W.; Sugardjito, J.; Rafiastanto, A.

    2010-11-01

    Degradation of tropical peats is a global concern due to large Carbon emission and loss of biodiversity. The degradation of tropical peats usually starts when the government drains and clears peat forests into open peats used for food crops, oil palm and industrial timber plantations. Major properties of tropical peat forests are high in Water Contents (WC), Loss on Ignition (LOI) and Total Organic Carbon (TOC), and low in peat pH, Dry Bulk Density (DBD), and Total Nitrogen (TN). In this study, we investigated impacts of drainage and land use change on these properties. We collected peat samples from peat forests, logged over peat forest, industrial timber plantation, community agriculture, and oil palms. We used independent t-tests and oneway ANOVA to analyze mean differences of the research variables. We found that peat pH, DBD, and TN tend to increase. A significant decrease of C/N ratio in oil palm and agriculture sites importantly denotes a high rate of peat decompositions. Water contents, LOI, and TOC are relatively constants. We suggest that changes in pH, DBD, TN and atomic C/N ratio are important indicators for assessing tropical peat degradation. We infer that land use change from tropical peat forests into cleared and drained peats used for intensive timber harvesting, oil palms and industrial timber plantations in Indonesia has greatly degraded major ecological function of tropical peats as Carbon storage.

  19. The preferential growth of branched GDGT source microorganisms under aerobic conditions in peat revealed by stable isotope probing experiments

    NASA Astrophysics Data System (ADS)

    Huguet, Arnaud; Meador, Travis B.; Laggoun-Défarge, Fatima; Könneke, Martin; Derenne, Sylvie; Hinrichs, Kai-Uwe

    2016-04-01

    Branched glycerol dialkyl glycerol tetraether (brGDGTs) membrane lipids are widely distributed in aquatic and terrestrial environments and are being increasingly used as temperature proxies. Nevertheless, little is known regarding the microorganisms that produce these lipids, which are found in especially high abundance in the anaerobic horizons of peat bogs. We initiated stable isotope probing incubations of peat samples from a Sphagnum-dominated peatland (Jura Mountains, France) to measure the incorporation of (D)-D2O and 13C-labeled dissolved inorganic carbon (DIC) into brGDGTs, and thus gauge the activity, growth, and turnover times of their source organisms. Peat samples were collected from two adjacent sites with contrasting humidity levels (hereafter called "fen" and "bog" sites). For each site, samples from the surficial aerobic layer (acrotelm) and deeper anaerobic layer (catotelm) were collected and were incubated under both anaerobic and aerobic conditions for the acrotelm samples and only anaerobic conditions for the catotelm. The incubations were performed at 12 ° C, consistent with the mean summer air temperature at the sampling site. After two months of incubation, there was no incorporation of 13C label in brGDGTs for samples incubated under either aerobic or anaerobic conditions, showing that brGDGT-producing bacteria are heterotrophic microorganisms, as previously observed in organo-mineral soils (Weijers et al., 2011). Similarly, little to no deuterium incorporation was observed for brGDGTs isolated from anaerobically-incubated deep samples. In contrast, in the aerobic incubations of acrotelm samples from bog and fen, the weighted average δD of brGDGT core lipids (CLs) increased by up to 3332‰ and 933‰ after two months, respectively, indicating that fresh brGDGT CLs were biosynthesized at the peat surface. D incorporation into brGDGT CLs converted to production rates ranging from 30-106 ng cm‑3y‑1 in the aerobic acrotelm from bog and

  20. How do climate and human impact affect Sphagnum peatlands under oceanic-continental climatic conditions? 2000 years of fire and hydrological history of a bog in Northern Poland

    NASA Astrophysics Data System (ADS)

    Marcisz, Katarzyna; Tinner, Willy; Colombaroli, Daniele; Kołaczek, Piotr; Słowiński, Michał; Fiałkiewicz-Kozieł, Barbara; Lamentowicz, Mariusz

    2014-05-01

    Climate change affects many natural processes and the same applies to human impact For instance climate change and anthropogenic activities may cause increased fire activity or change peatland dynamics. Currently it is still unknown how Sphagnum peatlands in the oceanic-continental transition zone of Poland may respond to combined effects of heat waves, drought and fire. The aim of the study was to reconstruct the last 2000 years palaeohydrology and fire history at Linje bog in Northern Poland. The main task was to determine the drivers of fire episodes, particularly to identify climatic and anthropogenic forcing. A two-meter peat core was extracted and subsampled with a high resolution. Micro- and macroscopic charcoal analyses were applied to determine past fire activity and the results compared with palaeohydrological reconstructions based on testate amoeba analysis. Palynological human indicators were used to reconstruct human activity. A depth-age model including 20 14C dates was constructed to calculate peat accumulation rates and charcoal influx. We hypothesised that: 1) fire frequency in Northern Poland was determined by climatic conditions (combination of low precipitation and heat waves), as reflected in peatland water table, and that 2) past fire episodes in the last millennium were intensified by human activity. Furthermore climate may have influenced human activity over harvest success and the carrying capacity. Our study shows that fire was important for the studied ecosystem, however, its frequency has increased in the last millennium in concomitance with land use activities. Landscape humanization and vegetation opening were followed by a peatland drying during the Little Ice Age (from ca. AD 1380). Similarly to other palaeoecological studies from Poland, Linje peatland possessed an unstable hydrology during the Little Ice Age. Increased fire episodes appeared shortly before the Little Ice Age and most severe fires were present in the time when

  1. Evaluating the impacts of re-vegetation of bare peat on blanket peat water tables

    NASA Astrophysics Data System (ADS)

    Shuttleworth, Emma; Richards, Rebecca; Evans, Martin; Agnew, Clive; Pilkington, Mike; Maskill, Rachael; Allott, Tim

    2015-04-01

    Studies of the hydrological impacts of peat restoration in blanket peat systems have focused on the impacts of drain and gully blocking on water tables. However, in the South Pennines of the UK large areas of previously bare blanket peat have been restored by re-vegetation. The effects of this restoration treatment on water table behaviour have not been fully evaluated. Preliminary data from space-for-time studies indicate that re-vegetation leads to significant rises in water tables and decreases in water table variability. Here we present additional data from a before-after-control-intervention (BACI) study to validate these preliminary observations. We also present meteorological, net radiation and evapotranspiration data to test the hypothesis that water table changes associated with re-vegetation are driven by changing evapotranspiration rates as bare peat surfaces re-vegetate. The wider ecosystem service benefits of water table increases associated with re-vegetation of bare peat are discussed.

  2. Spatial Genetic Structure of the Abundant and Widespread Peatmoss Sphagnum magellanicum Brid.

    PubMed

    Kyrkjeeide, Magni Olsen; Hassel, Kristian; Flatberg, Kjell Ivar; Shaw, A Jonathan; Yousefi, Narjes; Stenøien, Hans K

    2016-01-01

    Spore-producing organisms have small dispersal units enabling them to become widespread across continents. However, barriers to gene flow and cryptic speciation may exist. The common, haploid peatmoss Sphagnum magellanicum occurs in both the Northern and Southern hemisphere, and is commonly used as a model in studies of peatland ecology and peatmoss physiology. Even though it will likely act as a rich source in functional genomics studies in years to come, surprisingly little is known about levels of genetic variability and structuring in this species. Here, we assess for the first time how genetic variation in S. magellanicum is spatially structured across its full distribution range (Northern Hemisphere and South America). The morphologically similar species S. alaskense was included for comparison. In total, 195 plants were genotyped at 15 microsatellite loci. Sequences from two plastid loci (trnG and trnL) were obtained from 30 samples. Our results show that S. alaskense and almost all plants of S. magellanicum in the northern Pacific area are diploids and share the same gene pool. Haploid plants occur in South America, Europe, eastern North America, western North America, and southern Asia, and five genetically differentiated groups with different distribution ranges were found. Our results indicate that S. magellanicum consists of several distinct genetic groups, seemingly with little or no gene flow among them. Noteworthy, the geographical separation of diploids and haploids is strikingly similar to patterns found within other haploid Sphagnum species spanning the Northern Hemisphere. Our results confirm a genetic division between the Beringian and the Atlantic that seems to be a general pattern in Sphagnum taxa. The pattern of strong genetic population structuring throughout the distribution range of morphologically similar plants need to be considered in future functional genomic studies of S. magellanicum. PMID:26859563

  3. Sources of variability in peat composition and the role of peat age

    NASA Astrophysics Data System (ADS)

    Leifeld, Jens

    2016-04-01

    During peat formation decaying plant material undergoes partial decomposition that continuously transform its organic matter. As part of this transformation, aromatic moieties such as plant-borne polyphenols are considered to accumulate relative to more labile compounds such as carbohydrates. Here, 13C CPMAS-NMR data from 71 peat samples from sites across Europe (61°48' N - 46°49' N) are analyzed for their variability. Sites differ in their degree of peat disturbance and range from natural to long-term drained and thus strongly degraded. Application of a molecular mixing model to the NMR data indicated that, on average, peat consists by 27, 22, 21, 18, and 11 % of carbohydrates, aliphatics, aromatics, proteins, and char, respectively. Compositional variability was most pronounced for aromatics and carbohydrates. So far, half of the samples was age-dated using 14C. Calibrated 14C ages in the data set range from recent to c. 10000 years BP. Relationships between peat composition and age were non-linear and highly significant. Aromatic moieties accumulated with increasing peat age whereas O-containing moieties relatively declined, in line with a decrease in molar O/C ratios. The relative accumulation of aromatics was 250 % during 10000 years whereas O-containing moieties declined relatively by 65 %. About half of this selective accumulation and degradation occurred during the first 2000 years of peat accumulation, thereby reflecting higher microbial transformation rates during initial phases of built-up. Char content increased with peat age, possibly indicating selective preservation of char during peat formation. C/N ratios correlated significantly but bi-modal with age. The analysis shows that peat age is a reliable proxy for organic matter transformation in peatlands. Because rates and degree of transformation are derived from multiple sites, the found relationships seem to reveal a general pattern, at least for the studied boreal and temperate systems.

  4. 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

  5. Fiber Effects on Compressibility of Peat

    NASA Astrophysics Data System (ADS)

    Johari, N. N.; Bakar, I.; Razali, S. N. M.; Wahab, N.

    2016-07-01

    Fibers found in the soil, especially in peaty soil play an important role in the determination of soil compressibility. Peat soils are the results from the decomposition of organic matter and the type of peat can be classified based on the fibrous material in the soil. In the engineering field, peat soil was mostly known as soils that has a serious settlement with high compressibility index. From the previous research, fibers in the soil were influenced in compressibility in terms of size, shape, fibric, soil arrangement and etc. Hence, this study attempts the determination of fibers effects on the compressibility of peat using a 1-D oedometer consolidation test. The reconstituted peat samples of different particle sizes were used to determine the consolidation parameters and the results obtained from reconstituted samples were also compared with the undisturbed sample. 1-D oedometer consolidation tests were performed on the samples by using the load increment method. The results shows, the higher particle size (R3.35), give higher moisture content (w = 401.20%) and higher initial void ratio (eo = 5.74). In settlement prediction, the higher the fiber content will results the higher the compression index, therefore, it will cause high of settlement.

  6. Long-period astronomically forced peat deposits

    NASA Astrophysics Data System (ADS)

    Valero, Luis; Garcés, Miguel; Cabrera, Lluís; Sáez, Alberto

    2016-04-01

    Organic matter sequestration by peat accumulation constitutes a primary sink for carbon in the global carbon cycle. Disclosing the processes that control the formation and storage of peat at time scales ranging from 103-106 years is a non-solved issue important for understanding the global climate system. We analyzed a 7 million years long terrestrial record of Late Oligocene age from the coal-bearing As Pontes Basin in Northwestern Spain. Biochronological constraints were included in order to refine a former magnetostratigraphy, giving rise a robust age model. This data was used to perform a cyclostratigraphic analysis. The obtained results show that minima in the 405-kyr and 2.4-Myr eccentricity cycles play a key role in peat formation. Such nodes exhibit reduced precession amplitudes, thus avoiding extremes in seasons and seasonal contrast for a prolonged period of time. In the As Pontes Basin, this orbital configuration is associated with a decrease in siliciclastic sedimentation and enhanced peat formation. Feedbacks between equilibrium landscapes and ecosystem stability will lead to a deceleration of weathering and erosion rates in catchment areas and to minimize and stabilize the sediment flux along the sediment routing system. Mid-latitude peat burial could contribute to disturb the carbon cycle by removing (atmospheric) carbon at times of minimum eccentricity.

  7. Fixed-bed gasification research using US coals. Volume 11. Gasification of Minnesota peat. [Peat pellets and peat sods

    SciTech Connect

    Thimsen, D.; Maurer, R.E.; Pooler, A.R.; Pui, D.; Liu, B.; Kittelson, D.

    1985-05-01

    A single-staged, fixed-bed Wellman-Galusha gasifier coupled with a hot, raw gas combustion system and scrubber has been used to gasify numerous coals from throughout the United States. The gasification test program is organized as a coooperative effort by private industrial participants and governmental agencies. The consortium of participants is organized under the Mining and Industrial Fuel Gas (MIFGa) Group. This report is the eleventh volume in a series of reports describing the atmospheric pressure, fixed-bed gasification of US coals. This specific report describes the gasification of peat pellets and peat sods during 3 different test periods. 2 refs., 20 figs., 13 tabs.

  8. Immunomodulative properties of humic peat preparations

    NASA Astrophysics Data System (ADS)

    Stepchenko, L. M.; Syedykh, N. J.

    2010-05-01

    It is proved, that the humic peat preparations promote the resistance of plants, animals and poultry to the influence of both abyotyc and byotyc extreme factors of external environment, to action. It was shown by us before, that biologically active compounds from peat promote stability against different diseases of agricultural animals and poultry. We conducted researches of humic preparations influence (hydrohumate and oxyhumate) on several indexes of immunoreactivity of the organisms of chickens broilers, ostriches, cows and laboratory rats. It is found out, that adding of humic preparations to forage or drinking water results in the normalization of immunity indexes; in particular, leucocytes level, in the increase of the level of some classes of immunoglobuline in blood, of haemoglobin level, T- and B-lymphocytes level, as well as common unspecific resistance - lyzocymic, phagocytic and bactericidic activity. These results allow to suggest that the peat humic preparations show immunomodulative activity, influencing both on humoral and cel immunity links.

  9. Seasonal changes in Sphagnum peatland testate amoeba communities along a hydrological gradient.

    PubMed

    Marcisz, Katarzyna; Lamentowicz, Lukasz; Słowińska, Sandra; Słowiński, Michał; Muszak, Witold; Lamentowicz, Mariusz

    2014-10-01

    Testate amoebae are an abundant and functionally important group of protists in peatlands, but little is known about the seasonal patterns of their communities. We investigated the relationships between testate amoeba diversity and community structure and water table depth and light conditions (shading vs. insolation) in a Sphagnum peatland in Northern Poland (Linje mire) in spring and summer 2010. We monitored the water table at five sites across the peatland and collected Sphagnum samples in lawn and hummock micro-sites around each piezometer, in spring (3 May) and mid-summer (6 August) 2010. Water table differed significantly between micro-sites and seasons (Kruskal-Wallis test, p=0.001). The community structure of testate amoebae differed significantly between spring and summer in both hummock and lawn micro-sites. We recorded a small, but significant drop in Shannon diversity, between spring and summer (1.76 vs. 1.72). Strongest correlations were found between testate amoeba communities and water table lowering and light conditions. The relative abundance of mixotrophic species Hyalosphenia papilio, Archerella flavum and of Euglypha ciliata was higher in the summer. PMID:25176338

  10. Regional patterns of mercury content in snowpack, sphagnum, and fish in northeastern North America

    SciTech Connect

    Haines, T.; Mower, B.; Perry, R.

    1995-12-31

    High levels of mercury have been found in fish from lakes throughout the northeastern US and eastern Canada, in waters with no known local mercury source. If this mercury originates from anthropogenic emissions to the atmosphere, deposition should be higher near population centers or other point sources. The authors surveyed the mercury content of late-season snowpack, sphagnum moss, and fish at locations from southwestern Connecticut to northern Newfoundland to determine if such a pattern existed. Mercury in snow ranged 1.5 to 20 ng/L, and in sphagnum < 24 to 289 ng/g dry wt. Concentrations were generally highest at southwestern sites and lowest at northeastern sites with some exceptions. The highest concentrations in both media were at locations in Rhode Island and New Hampshire, and may reflect local source emissions. Excluding these sites, the range in concentration from south to north is only a factor of two or three. These values are similar to those reported in other areas and reflect the long atmospheric residence time of gaseous elemental mercury. Mercury concentration in fish ranged 0.1 to 1.0 ug/g wet wt. and showed no regional pattern. Rather, fish mercury concentration was affected by fish species and size, being highest in large predatory species such as smallmouth bass (Micropterus dolomieu), and lowest in small nonpredatory species such as yellow perch (Perca flavescens) and brook trout (Salvelinus fontinalis).

  11. Thermal energy storage composition comprising peat moss

    SciTech Connect

    Rueffel, P.G.

    1980-11-04

    Peat moss is used in a thermal energy storage composition to provide a network in which to trap an incongruently melting salt hydrate capable of storing thermal energy as latent heat of phase change. The peat moss network is effective in preventing the segregation of a dehydrated form of the salt between heating and cooling cycles. In a preferred embodiment that salt hydrate is the decahydrate of sodium sulphate. A nucleating agent such as sodium tetraborate decahydrate is included to prevent supercooling in the composition, and promote crystallization of the decahydrate of sodium sulphate.

  12. Properties and structure of raised bog peat humic acids

    NASA Astrophysics Data System (ADS)

    Klavins, Maris; Purmalis, Oskars

    2013-10-01

    Humic substances form most of the organic components of soil, peat and natural waters, and their structure and properties differ very much depending on their source. The aims of this study are to characterize humic acids (HAs) from raised bog peat, to evaluate the homogeneity of peat HAs within peat profiles, and to study peat humification impact on properties of HAs. A major impact on the structure of peat HAs have lignin-free raised bog biota (dominantly represented by bryophytes of different origin). On diagenesis scale, peat HAs have an intermediate position between the living organic matter and coal organic matter, and their structure is formed in a process in which more labile structures (carbohydrates, amino acids, etc.) are destroyed, while thermodynamically more stable aromatic and polyaromatic structures emerge as a result of abiotic synthesis. However, in comparison with soil, aquatic and other HAs, aromaticity of peat HAs is much lower. Comparatively, the raised bog peat HAs are at the beginning of the transformation process of living organic matter. Concentrations of carboxyl and phenolic hydroxyl groups change depending on the peat age and decomposition degree from where HAs have been isolated, and carboxylic acidity of peat HAs increases with peat depth and humification degree.

  13. Development of a new peat-based oil sorbent using peat pyrolysis.

    PubMed

    Klavins, Maris; Porshnov, Dmitry

    2013-01-01

    The growing use and transport of crude oil and oil products has led to increasing numbers of oil spillages of various scales. Oil sorbents have been extensively used for remediation of the consequences of such accidents. The aim of this study is to investigate the possible use of peat and its thermal treatment products for oil sorption. Peat as an oil sorbent has poor buoyancy characteristics, relatively low oil sorption capacity and low hydrophobicity. However, thermal treatment (low-temperature pyrolysis and synthesis of peat-based activated coal) helps to significantly improve its sorptive characteristics. Peat is a potential material for oil sorption because it has such advantages as low cost, biodegradability and relatively high parameters of specific surface area and porosity. The processes and structural changes taking place during low-temperature pyrolysis have been studied by means of IR spectroscopy, thermogravimetry and scanning electron microscopy. PMID:24191492

  14. INFLUENCE OF PEAT ON FENTON OXIDATION

    EPA Science Inventory

    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 ("-FeOOH) ore, peat, and H2O2 (0.13 mM). A simple method of kinetic analysi...

  15. 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

  16. Feasibility of a peat biogasification process

    NASA Astrophysics Data System (ADS)

    Buivid, M. G.; Wise, D. L.; Rader, A. M.; McCarty, P. L.; Owen, W. F.

    1980-07-01

    The feasibility of a two-stage biogasification process for the conversion of peat reserves, the energy content of which in the United States is greater than that of uranium, shale oil or petroleum and natural gas combined, into pipeline-quality methane is investigated. Samples of wet-harvested reed-sedge peat were pretreated in alkaline and nonalkaline conditions in the presence and absence of oxidation in order to determine the most favorable conditions for the conversion of cellulosic and lignaceous fractions to water-soluble, fermentable compounds, and the resulting products were subjected to anaerobic fermentation to methane. Conversion efficiencies obtained reveal that up to 26% of the initial heat content of peat was converted to methane when alkaline heat pretreatment was employed. Analysis of the process parameters by a computer model to determine equipment sizes, mass and energy balances and costs indicates that for a 79,200 GJ/day plant the total capital requirement would be $323,000,000, annual operating costs would be $44,000,000 and average SNG cost would be $3.16/GJ, assuming a 90% stream factor with a delivered peat slurry costing $0.0033/kg.

  17. Equivalent weight of humic acid from peat

    USGS Publications Warehouse

    Pommer, A.M.; Breger, I.A.

    1960-01-01

    By means of discontinuous titration, the equivalent weight of humic acid isolated from a peat was found to increase from 144 to 183 between the third and fifty-second day after the humic acid was dissolved. Infra-red studies showed that the material had probably condensed with loss of carbonyl groups. ?? 1960.

  18. Some geochemical features of peat lands of the western peat-marsh range

    NASA Astrophysics Data System (ADS)

    Chekin, G. V.; Kreshtapova, V. N.

    2010-05-01

    The terrain of the western peat-marsh range within Russia coincides with administrative borders of Bryansk range, and as a whole differs uniformity of natural settings. It has affected relative uniformity of type of the peat deposits propagated here, as a rule, low moor phylum, is frequent with the raised ash content and a degree of decomposition. For an assessment of concentration of trace substances in peat comparison of their content with clarke is used. In peat of studied area bunches of trace substances vigorous (transitive - Co, Mo, Zn, Pb, Cs, Cd are secured; lowmoor - Co, Mo, Ni, Cu, Cd, Cs), an average (transitive - Ni, Cu; lowmoor - Zn, Sr, Pb) and weak (transitive - Cr, Mn, Sr, Li; low moor - Cr, Mn, Li) accumulations. High motility of trace substances (Co, Mo, Zn, Cu, Mn) in peat is shown. The greatest motility manganese - to 90 %, the least cobalt - 20-30 % possesses. Correlation coefficients and the regression equations, between the total content and exchange forms of trace substances are calculated. The received results will be co-ordinated with literary data. The increased content of trace substances in peat high layers is noted. It is bound as about dust receipt on a moor surface, and to bioaccumulation of trace substances by plants.

  19. Laboratory evaporation experiments in undisturbed peat columns for determining peat soil hydraulic properties

    NASA Astrophysics Data System (ADS)

    Dettmann, Ullrich; Frahm, Enrico; Bechtold, Michel

    2013-04-01

    One of the key parameters controlling greenhouse gas (GHG) emissions from organic soils is water table depth. Thus, a detailed analysis of the hydrology is essential for an accurate spatial upscaling of the information of local GHG emission measurements to the regional and national scale. For the interpretation and numerical modeling of water table fluctuations, knowledge about soil hydraulic parameters is crucial. In contrast to mineral soils, the hydraulic properties of organic soils differ in several aspects. Due to the high amount of organic components, strong heterogeneity, and shrinkage and swelling of peat, accompanied by changing soil volume and bulk density, it is difficult to describe peat soil moisture dynamics with standard hydraulic functions developed for mineral soils. The objective of this study was to determine soil hydraulic properties for various undisturbed peat columns (diameter: 30 cm, height: 20 cm). Laboratory evaporation experiments were conducted for peat soils from five different test sites of the German joint research project "Organic Soils". Due to different land use histories, the peat samples covered a broad range of degradation states, which is known to strongly influence peat soil hydraulic properties. Pressure head, moisture content, weight loss and water level were monitored during the evaporation experiment. In numerical simulations using HYDRUS-1D the experimental data were used for an inverse-estimation of the soil hydraulic parameters using "shuffled complex evolution" and "covariance matrix adaption" optimization schemes. Besides the commonly applied van Genuchten-Mualem parameterization, several alternative soil parameterizations are evaluated.

  20. The Cultivation of Arabidopsis for Experimental Research Using Commercially Available Peat-Based and Peat-Free Growing Media

    PubMed Central

    Drake, Tiffany; Keating, Mia; Summers, Rebecca; Yochikawa, Aline; Pitman, Tom

    2016-01-01

    Experimental research involving Arabidopsis thaliana often involves the quantification of phenotypic traits during cultivation on compost or other growing media. Many commercially-available growing media contain peat, but peat extraction is not sustainable due to its very slow rate of formation. Moreover, peat extraction reduces peatland biodiversity and releases stored carbon and methane into the atmosphere. Here, we compared the experimental performance of Arabidopsis on peat-based and several types of commercially-available peat-free growing media (variously formed from coir, composted bark, wood-fibre, and domestic compost), to provide guidance for reducing peat use in plant sciences research with Arabidopsis. Arabidopsis biomass accumulation and seed yield were reduced by cultivation on several types of peat-free growing media. Arabidopsis performed extremely poorly on coir alone, presumably because this medium was completely nitrate-free. Some peat-free growing media were more susceptible to fungal contamination. We found that autoclaving of control (peat-based) growing media had no effect upon any physiological parameters that we examined, compared with non-autoclaved control growing media, under our experimental conditions. Overall, we conclude that Arabidopsis performs best when cultivated on peat-based growing media because seed yield was almost always reduced when peat-free media were used. This may be because standard laboratory protocols and growth conditions for Arabidopsis are optimized for peat-based media. However, during the vegetative growth phase several phenotypic traits were comparable between plants cultivated on peat-based and some peat-free media, suggesting that under certain circumstances peat-free media can be suitable for phenotypic analysis of Arabidopsis. PMID:27088495

  1. The Cultivation of Arabidopsis for Experimental Research Using Commercially Available Peat-Based and Peat-Free Growing Media.

    PubMed

    Drake, Tiffany; Keating, Mia; Summers, Rebecca; Yochikawa, Aline; Pitman, Tom; Dodd, Antony N

    2016-01-01

    Experimental research involving Arabidopsis thaliana often involves the quantification of phenotypic traits during cultivation on compost or other growing media. Many commercially-available growing media contain peat, but peat extraction is not sustainable due to its very slow rate of formation. Moreover, peat extraction reduces peatland biodiversity and releases stored carbon and methane into the atmosphere. Here, we compared the experimental performance of Arabidopsis on peat-based and several types of commercially-available peat-free growing media (variously formed from coir, composted bark, wood-fibre, and domestic compost), to provide guidance for reducing peat use in plant sciences research with Arabidopsis. Arabidopsis biomass accumulation and seed yield were reduced by cultivation on several types of peat-free growing media. Arabidopsis performed extremely poorly on coir alone, presumably because this medium was completely nitrate-free. Some peat-free growing media were more susceptible to fungal contamination. We found that autoclaving of control (peat-based) growing media had no effect upon any physiological parameters that we examined, compared with non-autoclaved control growing media, under our experimental conditions. Overall, we conclude that Arabidopsis performs best when cultivated on peat-based growing media because seed yield was almost always reduced when peat-free media were used. This may be because standard laboratory protocols and growth conditions for Arabidopsis are optimized for peat-based media. However, during the vegetative growth phase several phenotypic traits were comparable between plants cultivated on peat-based and some peat-free media, suggesting that under certain circumstances peat-free media can be suitable for phenotypic analysis of Arabidopsis. PMID:27088495

  2. Relating changes of organic matter composition of two German peats to climatic conditions during peat formation

    NASA Astrophysics Data System (ADS)

    Knicker, Heike; Nikolova, Radoslava; Rumpel, Cornelia; González-Vila, Francisco, J.; Drösler, Matthias

    2010-05-01

    Peatlands have been recognized as an important factor within the global C-cycle, since they store about one-third of the global terrestrial C-pool. Furthermore, peat deposits have the potential to record detailed paleoclimatic and - vegetational changes. They are formed in peculiar paleoecosystems where the slow biodegradation of plant residues depends on a series of pedo-climatic and hydromorphic factors leading to a progressive accumulation of organic matter stabilized in different evolutionary stages. Thus, its chemical composition should be applicable as a fingerprint of former prevailing environmental conditions and vegetation configurations. The aim of the present work was to identify this fingerprint in the cores of two German fens, one derived from the Havelland close to Berlin (Großer Bolchow) and the other derived from the alpine region of Bavaria (Kendlmühlfilzen) by investigating the organic matter transformation as a function of peat depths. The C/N ratios and δ13C values revealed several distinctive trends in the two profiles related to prevailing peat forming conditions. Compared to the other layers, at depths of 14-85 cm and 132-324 cm in the Kendlmühlfilzen fen, high C/N ratios and less depleted δ13C values, indicated that the accumulation of these two layers occurred during a humid and cold period. In the case of the "Großer Bolchow", algal contributions were clearly detected using δ13C values. Solid-state 13C NMR spectroscopy demonstrated loss of celluloses and accumulation of lipids and lignin derivatives during peatification, confirming that under the mostly O2-depleted conditions in peats, decomposition was selective. The results obtained by pyrolysis-GC/MS were in good agreement with the NMR data showing that processes ascribed to gradual biotransformation of the lignin occurred in both peats. However, the "Großer Bolchow" peat revealed a more advanced decomposition stage then the "Kendlmühlfilzen" peat, which is in agreement with

  3. Trialling a novel peat fuel extraction and reclamation technique: Vegetation recovery and peatland-atmosphere carbon fluxes

    NASA Astrophysics Data System (ADS)

    Morris, Paul J.; Wihelm, Lana P.; Solondz, Danielle M.; Waddington, J. Mike

    2013-04-01

    CO2 flux due to deep water-table drawdown. However, average methane fluxes from the experimental plot (274 mg CH4 m-2 d-1) were highly elevated compared to those from hummocks (18 mg CH4 m-2 d-1) and hollows (44 mg CH4 m-2 d-1) in the reference plot, representing a major drawback to transplanting into an inundated extraction pit. During the first summer immediately after extraction the transplanted moss community appeared healthy, even though many of the vascular plants had been killed. However, by the second year proportional coverage of moss in the experimental plot had declined from 63 % to 41 %, which contrasted with an increase in moss coverage in both hummocks and hollows at the reference plot. Nonetheless, Sphagnum growth in the remaining healthy communities was strong in the second year (156 g m-2 moss) compared to the reference plot (104 g m-2 moss). Our findings indicate that PBR has great potential as a means for extracting peat without causing either i) irreparable damage to plant communities, or ii) elevated CO2 flux. However, these potential advantages must be carefully weighed against the highly elevated CH4 release from the transplant pit.

  4. Acid-shock, aluminium, and presence of Sphagnum aurantiacum: effect on embryological development in the common frog, Rana temporaria and the moor frog, Rana arvalis

    SciTech Connect

    Olsson, M.; Hogstrand, C.; Dahlberg, A.; Berglind, S.A.

    1987-07-01

    During the last two decades, several effects of acidification have been shown, e.g., enhanced leaching of metals from sediments and soil. Furthermore, an increased growth of Sphagnum aurantiacum frequently occurs in acidified waters. The aim of the present study is to investigate some effects of acidification on the embryological development on two Anurans. The toxicity of aluminium is thought to vary with pH. The highest toxicity of aluminium in the hydroxyl form have been found at pH 5. In the present study a laboratory experiment was performed to investigate the toxicity of Al to frog embryos in water with pH 5.0. In acidified waters Sphagnum and especially S. aurantiacum, is competitive and quickly become established. It has been indicated that frog spawn deposited on Sphagnum show an unusually high mortality and questions have been raised if Sphagnum reinforces the detrimental effects of acidification on Anuran reproduction.

  5. Comparison of different methods to determine the degree of peat decomposition in peat bogs

    NASA Astrophysics Data System (ADS)

    Biester, H.; Knorr, K.-H.; Schellekens, J.; Basler, A.; Hermanns, Y.-M.

    2013-11-01

    Peat humification or decomposition is a frequently used proxy to extract past time changes in hydrology and climate from peat bogs. During the past century several methods to determine changes in peat decomposition have been introduced. Most of these methods are operationally defined only and the chemical changes underlying the decomposition process are often poorly understood and lack validation. Due to the chemically undefined nature of many humification analyses the comparison of results obtained by different methods is difficult if not misleading. In this study we compared changes in peat decomposition in cores of two peat bogs (Königsmoor (KK), Kleines Rotes Bruch, KRB) from the Harz Mountains (Germany) using C / N ratios, Fourier Transform Infrared spectra absorption (FTIR) intensities, Rock Eval® oxygen- and hydrogen indices, δ13C and δ15N isotopic signatures and UV-absorption of NaOH peat extracts. In addition, one of the cores was analysed for changes in the peat's molecular composition using pyrolysis gas chromatography mass spectrometry (pyrolysis-GC-MS). Records of decomposition proxies show similar historical development at both sites, indicating external forcing such as climate as controlling process. Moreover, all decomposition proxies except UV-ABS and δ15N isotopes show similar patterns in their records and thus reflect in different extents signals of decomposition. Pyrolysis-GC-MS analyses of the KK core reveal that changes in peat molecular chemistry are mainly attributed to decomposition processes and to a lesser extend to changes in vegetation. Changes in the abundance of molecular compounds indicate that peat decomposition in the KK bog is mainly characterized by preferential decomposition of phenols and polysaccharides and relative enrichment of aliphatics during drier periods. Enrichment of lignin and other aromatics during decomposition was also observed but showed less variation, and presumably reflects changes in vegetation

  6. Metatranscriptomic analysis of arctic peat soil microbiota.

    PubMed

    Tveit, Alexander T; Urich, Tim; Svenning, Mette M

    2014-09-01

    Recent advances in meta-omics and particularly metatranscriptomic approaches have enabled detailed studies of the structure and function of microbial communities in many ecosystems. Molecular analyses of peat soils, ecosystems important to the global carbon balance, are still challenging due to the presence of coextracted substances that inhibit enzymes used in downstream applications. We sampled layers at different depths from two high-Arctic peat soils in Svalbard for metatranscriptome preparation. Here we show that enzyme inhibition in the preparation of metatranscriptomic libraries can be circumvented by linear amplification of diluted template RNA. A comparative analysis of mRNA-enriched and nonenriched metatranscriptomes showed that mRNA enrichment resulted in a 2-fold increase in the relative abundance of mRNA but biased the relative distribution of mRNA. The relative abundance of transcripts for cellulose degradation decreased with depth, while the transcripts for hemicellulose debranching increased, indicating that the polysaccharide composition of the peat was different in the deeper and older layers. Taxonomic annotation revealed that Actinobacteria and Bacteroidetes were the dominating polysaccharide decomposers. The relative abundances of 16S rRNA and mRNA transcripts of methanogenic Archaea increased substantially with depth. Acetoclastic methanogenesis was the dominating pathway, followed by methanogenesis from formate. The relative abundances of 16S rRNA and mRNA assigned to the methanotrophic Methylococcaceae, primarily Methylobacter, increased with depth. In conclusion, linear amplification of total RNA and deep sequencing constituted the preferred method for metatranscriptomic preparation to enable high-resolution functional and taxonomic analyses of the active microbiota in Arctic peat soil. PMID:25015892

  7. Metatranscriptomic Analysis of Arctic Peat Soil Microbiota

    PubMed Central

    Tveit, Alexander T.

    2014-01-01

    Recent advances in meta-omics and particularly metatranscriptomic approaches have enabled detailed studies of the structure and function of microbial communities in many ecosystems. Molecular analyses of peat soils, ecosystems important to the global carbon balance, are still challenging due to the presence of coextracted substances that inhibit enzymes used in downstream applications. We sampled layers at different depths from two high-Arctic peat soils in Svalbard for metatranscriptome preparation. Here we show that enzyme inhibition in the preparation of metatranscriptomic libraries can be circumvented by linear amplification of diluted template RNA. A comparative analysis of mRNA-enriched and nonenriched metatranscriptomes showed that mRNA enrichment resulted in a 2-fold increase in the relative abundance of mRNA but biased the relative distribution of mRNA. The relative abundance of transcripts for cellulose degradation decreased with depth, while the transcripts for hemicellulose debranching increased, indicating that the polysaccharide composition of the peat was different in the deeper and older layers. Taxonomic annotation revealed that Actinobacteria and Bacteroidetes were the dominating polysaccharide decomposers. The relative abundances of 16S rRNA and mRNA transcripts of methanogenic Archaea increased substantially with depth. Acetoclastic methanogenesis was the dominating pathway, followed by methanogenesis from formate. The relative abundances of 16S rRNA and mRNA assigned to the methanotrophic Methylococcaceae, primarily Methylobacter, increased with depth. In conclusion, linear amplification of total RNA and deep sequencing constituted the preferred method for metatranscriptomic preparation to enable high-resolution functional and taxonomic analyses of the active microbiota in Arctic peat soil. PMID:25015892

  8. Sphagnum physiology in the context of changing climate: emergent influences of genomics, modelling and host-microbiome interactions on understanding ecosystem function.

    PubMed

    Weston, David J; Timm, Collin M; Walker, Anthony P; Gu, Lianhong; Muchero, Wellington; Schmutz, Jeremy; Shaw, A Jonathan; Tuskan, Gerald A; Warren, Jeffrey M; Wullschleger, Stan D

    2015-09-01

    Peatlands harbour more than one-third of terrestrial carbon leading to the argument that the bryophytes, as major components of peatland ecosystems, store more organic carbon in soils than any other collective plant taxa. Plants of the genus Sphagnum are important components of peatland ecosystems and are potentially vulnerable to changing climatic conditions. However, the response of Sphagnum to rising temperatures, elevated CO2 and shifts in local hydrology have yet to be fully characterized. In this review, we examine Sphagnum biology and ecology and explore the role of this group of keystone species and its associated microbiome in carbon and nitrogen cycling using literature review and model simulations. Several issues are highlighted including the consequences of a variable environment on plant-microbiome interactions, uncertainty associated with CO2 diffusion resistances and the relationship between fixed N and that partitioned to the photosynthetic apparatus. We note that the Sphagnum fallax genome is currently being sequenced and outline potential applications of population-level genomics and corresponding plant photosynthesis and microbial metabolic modelling techniques. We highlight Sphagnum as a model organism to explore ecosystem response to a changing climate and to define the role that Sphagnum can play at the intersection of physiology, genetics and functional genomics. PMID:25266403

  9. [Oribatid mites (Acariformes, Oribatei) as an index of postpyrogenous changes in podzol and peat soils of boreal forests].

    PubMed

    Kudriasheva, I V; Laskova, L M

    2002-01-01

    Population changes of oribatid mites were studied in a bilberry-moss spruce stand and shrub-peat moss pine stand caused by ground fire. The fire resulted in a drop of population density and changes in the species composition of mites in both forest types. In the case of the spruce stand, the restoration of species composition proceeded parallel to the formation of a bilberry-moss cover and litter and became distinct four years after the fire. In the case of pine stand, the fire enveloped only the peripheral region. After the sphagnum cover burned out, the moor dehydration began and the mineralized organogenic substrate emerged. Here, the oribatid complex was significantly rearranged and the previously dominating moisture-loving species were replaced by the mesophilous-xerophilous species typical predominantly for mineralized soils. This explains why the oribatid species composition in the burned pine stand is more similar to that in the control spruce stand than to that in the control pine stand. PMID:12068434

  10. Mapping peat morphology in sag pond with ground penetrating radar

    NASA Astrophysics Data System (ADS)

    Iryanti, Mimin; Nugraha, Harya Dwi; Setiawan, Tedy; Bijaksana, Satria

    2013-09-01

    In the tropics peat is commonly found in low-land areas. In certain condition, however, peat could also be found in high elevation, such as in sag ponds near fault zones. Information regarding thickness and morphology of peat in Sag Pond can be used to infer fault activities in the past. In this study, we attempt to identify the thickness and morphology of peat in a sag pond at Karyawangi Village near the Lembang fault, to the north of Bandung, West Java, Indonesia. We use ground penetrating radar (GPR) method with 250 Mhz antennae in several lines. The data were them processes using Reflexw software. The results show that in each survey line, peat layer is clearly identifiable. In some lines, the peat layer is continous while in some other, the peat layer is undulated. The peat layer in general in about 0.5 to 2 m thick. In conclusion, the GPR method with 250 Mhz antennae is suitable for mapping peat thickness and morphology in Sag Pond.

  11. 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. PMID:27247870

  12. Mining for Nonribosomal Peptide Synthetase and Polyketide Synthase Genes Revealed a High Level of Diversity in the Sphagnum Bog Metagenome

    PubMed Central

    Müller, Christina A.; Oberauner-Wappis, Lisa; Peyman, Armin; Amos, Gregory C. A.; Wellington, Elizabeth M. H.

    2015-01-01

    Sphagnum bog ecosystems are among the oldest vegetation forms harboring a specific microbial community and are known to produce an exceptionally wide variety of bioactive substances. Although the Sphagnum metagenome shows a rich secondary metabolism, the genes have not yet been explored. To analyze nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs), the diversity of NRPS and PKS genes in Sphagnum-associated metagenomes was investigated by in silico data mining and sequence-based screening (PCR amplification of 9,500 fosmid clones). The in silico Illumina-based metagenomic approach resulted in the identification of 279 NRPSs and 346 PKSs, as well as 40 PKS-NRPS hybrid gene sequences. The occurrence of NRPS sequences was strongly dominated by the members of the Protebacteria phylum, especially by species of the Burkholderia genus, while PKS sequences were mainly affiliated with Actinobacteria. Thirteen novel NRPS-related sequences were identified by PCR amplification screening, displaying amino acid identities of 48% to 91% to annotated sequences of members of the phyla Proteobacteria, Actinobacteria, and Cyanobacteria. Some of the identified metagenomic clones showed the closest similarity to peptide synthases from Burkholderia or Lysobacter, which are emerging bacterial sources of as-yet-undescribed bioactive metabolites. This report highlights the role of the extreme natural ecosystems as a promising source for detection of secondary compounds and enzymes, serving as a source for biotechnological applications. PMID:26002894

  13. Sphagnum N and P Stoichiometry Indicates P-limitation on N2 Fixation in Ombrotrophic Bogs

    NASA Astrophysics Data System (ADS)

    Zivkovic, T.; Moore, T. R.; Disney, K.

    2015-12-01

    Biological N2 fixation is an important N input in ombrotrophic, nutrient poor and Sphagnum dominated bogs. As an energetically costly process, by which each N2 molecule is fixed to a cost of 16ATP molecules, N2 fixation might be P limited process. In this study we tested whether moss P and N concentrations, and N:P ratios could explain N2 fixation in the top 6cm photosynthetically active Sphagnum moss across eight ombrotrophic bogs along south-north geographical gradient in Ontario and Quebec. Under constant environmental conditions, we incubated subsamples of the surface Sphagnum mosses by using both, acetylene reduction assays (ARA) and 15N2 enriched method to measure N2 fixation rates. Same subsamples were later analyzed for N and P concentrations. Our preliminary data show that the increase of P concentration within moss capitula is related to a significant linear increase of ARA rates (R2=0.18, p<0.0001, N=150). N:P ratios showed a significant negative linear relationship with ARA (R2=0.34, p<0.0001, N=150) indicating that P limitation in the photosynthetically active part of mosses in bogs may also indicate P limitation on microbial N2 fixation

  14. Mining for Nonribosomal Peptide Synthetase and Polyketide Synthase Genes Revealed a High Level of Diversity in the Sphagnum Bog Metagenome.

    PubMed

    Müller, Christina A; Oberauner-Wappis, Lisa; Peyman, Armin; Amos, Gregory C A; Wellington, Elizabeth M H; Berg, Gabriele

    2015-08-01

    Sphagnum bog ecosystems are among the oldest vegetation forms harboring a specific microbial community and are known to produce an exceptionally wide variety of bioactive substances. Although the Sphagnum metagenome shows a rich secondary metabolism, the genes have not yet been explored. To analyze nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs), the diversity of NRPS and PKS genes in Sphagnum-associated metagenomes was investigated by in silico data mining and sequence-based screening (PCR amplification of 9,500 fosmid clones). The in silico Illumina-based metagenomic approach resulted in the identification of 279 NRPSs and 346 PKSs, as well as 40 PKS-NRPS hybrid gene sequences. The occurrence of NRPS sequences was strongly dominated by the members of the Protebacteria phylum, especially by species of the Burkholderia genus, while PKS sequences were mainly affiliated with Actinobacteria. Thirteen novel NRPS-related sequences were identified by PCR amplification screening, displaying amino acid identities of 48% to 91% to annotated sequences of members of the phyla Proteobacteria, Actinobacteria, and Cyanobacteria. Some of the identified metagenomic clones showed the closest similarity to peptide synthases from Burkholderia or Lysobacter, which are emerging bacterial sources of as-yet-undescribed bioactive metabolites. This report highlights the role of the extreme natural ecosystems as a promising source for detection of secondary compounds and enzymes, serving as a source for biotechnological applications. PMID:26002894

  15. Effects of acidification on macrophyte growth in the HUMEX Lake Skjervatjern, with special emphasis on Sphagnum auriculatum

    SciTech Connect

    Brandrud, T.E.; Johansen, S.W. )

    1994-01-01

    Transplantation experiments for the study of aquatic macrophyte growth and vitality were carried out in the HUMEX Lake Skjervatjern. Plants (preferentially indigenous) were transplanted to plastic pots in the acid-treated (A) basin and the control (B) basin. During the first phase of the experiments in 1991-1992, shortly after start of acidification treatment, the following trends were apparent: (1) The isoetic plants (Isoetes lacustris, Littorella uniflora, and Lobelia dortmanna) showed similar growth and vitality responses in the two Skjervatjern basins. (2) The elodeid species showed a slightly different response in the two basins. Juncus bulbosus exhibited a slightly higher growth rate in the acidified A basin. Myriophyllum alterniflorum died out after less than a growing season in the treated basin A, while a few shoots survived in basin B. (3) The transplanted shoots of submerged Sphagnum auriculatum showed a decreased growth in the acidified basin less than a year after start of treatment. This contrasts the results of other lake acidification studies where submerged Sphagnum mats were found to increase. The decreased growth of Sphagnum auriculatum after treatment seems most probably to be due to the increased SO[sub 4] concentrations, or to increased competition with epiphytic green algae. 43 refs., 12 figs.

  16. Comparison of different methods to determine the degree of peat decomposition in peat bogs

    NASA Astrophysics Data System (ADS)

    Biester, H.; Knorr, K.-H.; Schellekens, J.; Basler, A.; Hermanns, Y.-M.

    2014-05-01

    Peat humification or decomposition is a frequently used proxy to extract past time changes in hydrology and climate from peat bogs. During the past century several methods to determine changes in peat decomposition have been introduced. Most of these methods are operationally defined only and the chemical changes underlying the decomposition process are often poorly understood and lack validation. Owing to the chemically undefined nature of many humification analyses the comparison of results obtained by different methods is difficult. In this study we compared changes in peat decomposition proxies in cores of two peat bogs (Königsmoor, KK; Kleines Rotes Bruch, KRB) from the Harz Mountains (Germany) using C / N ratios, Fourier transform infrared spectra absorption (FTIR) intensities, Rock Eva® oxygen and hydrogen indices, δ13C and δ15N isotopic signatures and UV-absorption (UV-ABS) of NaOH peat extracts. In order to explain parallels and discrepancies between these methods, one of the cores was additionally analysed by pyrolysis gas chromatography mass spectrometry (pyrolysis-GC-MS). Pyrolysis-GC-MS data provide detailed information on a molecular level, which allows differentiation of both changes attributed to decomposition processes and changes in vegetation. Principal component analysis was used to identify and separate the effects of changes in vegetation pattern and decomposition processes because both may occur simultaneously upon changes in bog hydrology. Records of decomposition proxies show similar historical development at both sites, indicating external forcing such as climate as controlling the process. All decomposition proxies except UV-ABS and δ15N isotopes show similar patterns in their records and reflect to different extents signals of decomposition. The molecular composition of the KK core reveals that these changes are mainly attributed to decomposition processes and to a lesser extent to changes in vegetation. Changes in the molecular

  17. Effect of Water Content Components on Desiccation and Recovery in Sphagnum Mosses

    PubMed Central

    Hájek, Tomáš; Beckett, Richard P.

    2008-01-01

    Background and Aims The basic parameters of water relations were measured in Sphagnum mosses. The relationships of these parameters to the photosynthetic response to desiccation and the ecology of these mosses were then tested. Methods The water relations parameters of six Sphagnum species (mosses typical of wet habitats) and Atrichum androgynum (a moss more typical of mesophytic conditions) were calculated from pressure–volume isotherms. Photosynthetic properties during and after moderate desiccation were monitored by chlorophyll fluorescence. Key Results When desiccated, the hummock-forming species S. fuscum and S. magellanicum lost more water before turgor started dropping than other sphagna inhabiting less exposed habitats (73 % compared with 56 % on average). Osmotic potentials at full turgor were similar in all species, with an average value of −1·1 MPa. Hummock sphagna had clearly more rigid cell walls than species of wet habitats (ε = 3·55 compared with 1·93 MPa). As a result, their chlorophyllous cells lost turgor at higher relative water contents (RWCs) than species of wet habitats (0·61 compared with 0·46) and at less negative osmotic potentials (–2·28 compared with −3·00 MPa). During drying, ΦPSII started declining earlier in hummock species (at an RWC of 0·65 compared with 0·44), and Fv/Fm behaved similarly. Compared with other species, hummock sphagna desiccated to −20 or −40 MPa recovered more completely after rehydration. Atrichum androgynum responded to desiccation similarly to hummock sphagna, suggesting that their desiccation tolerance may have a similar physiological basis. Conclusions Assuming a fixed rate of desiccation, the higher water-holding capacities of hummock sphagna will allow them to continue metabolism for longer than other species. While this could be viewed as a form of ‘desiccation avoidance’, hummock species also recover faster than other species during rehydration, suggesting that they have higher

  18. The decomposition of vegetation and soil in marginal peat-forming landscapes: climate simulations to quantify gaseous and dissolved carbon fluxes and the effects on peat accumulation and drinking water treatment

    NASA Astrophysics Data System (ADS)

    Ritson, J.; Bell, M.; Clark, J. M.; Graham, N.; Templeton, M.; Brazier, R.; Verhoef, A.; Freeman, C.

    2013-12-01

    Peatlands in the UK represent a large proportion of the soil carbon store, however there is concern that some systems may be switching from sinks to sources of carbon. The accumulation of organic material in peatlands results from the slow rates of decomposition typically occurring in these regions. Climate change may lead to faster decomposition which, if not matched by an equivalent increase in net primary productivity and litter fall, may tip the balance between source and sink. Recent trends have seen a greater flux of dissolved organic matter (DOM) from peatlands to surface waters and a change in DOM character, presenting challenges to water treatment, for example in terms of increased production of disinfectant by-products (DBPs). Peat systems border a large proportion of reservoirs in the UK so uncertainty regarding DOM quantity and quality is a concern for water utilities. This study considered five peatland vegetation types (Sphagnum spp., Calluna vulgaris, Molinea caerulea, peat soil and mixed litter) collected from the Exmoor National Park, UK where it is hypothesised that peat formation may be strongly affected by future changes to climate. A factorial experiment design to simulate climate was used, considering vegetation type, temperature and rainfall amount using a current baseline and predictions from the UKCP09 model. Gaseous fluxes of carbon were monitored over a two month period to quantify the effect on carbon mineralisation rates while 13C NMR analysis was employed to track which classes of compounds decayed preferentially. The DOM collected was characterised using UV and fluorescence techniques before being subject to standard drinking water treatment processes (coagulation/flocculation followed by chlorination). The effect of the experimental factors on DOM amenability to removal and propensity to form DBPs was then considered, with both trihalomethane (THM) and haloacetonitrile (HAN) DBP classes monitored. Initial results have shown a

  19. Comparative studies of Eocene silicified peat and lignite: transition between peat and lignite

    SciTech Connect

    Ting, F.T.C.

    1985-01-01

    Silicified Eocene peats with excellent preserved cellular structures were found in lignite beds in western North Dakota and were comparatively studied. The well preserved plant tissues resemble that of modern Taxodium peat. The most striking difference between silicified peat and lignite is the disappearance of cell cavities when peat is transformed to lignite, a phenomenon caused primarily by compaction rather than cell wall swelling through humification or gelification. The differences between textinite and ulminite can be traced back to the differences between early wood and late wood of the secondary xylem. What appear to be cutinites in lignite are compressed cortex tissues of young plants. Silicified leaf and cortex tissues contain more visible fluorinite exhibiting brilliant fluorescence. Clustering phloem fibers or stone cells give rise to a material resembling resinite but are more akin to huminite A and/or suberinite. They converge to vitrinite when vitrinite reflectance exceeds 0.6%. Alternating banded phloem fibers and phloem parenchyma give rise to alternating layers of huminite A and huminite B. True micrinite does occur in lignite but in limited quantities.

  20. Evapotranspiration of tropical peat swamp forests.

    PubMed

    Hirano, Takashi; Kusin, Kitso; Limin, Suwido; Osaki, Mitsuru

    2015-05-01

    In Southeast Asia, peatland is widely distributed and has accumulated a massive amount of soil carbon, coexisting with peat swamp forest (PSF). The peatland, however, has been rapidly degraded by deforestation, fires, and drainage for the last two decades. Such disturbances change hydrological conditions, typically groundwater level (GWL), and accelerate oxidative peat decomposition. Evapotranspiration (ET) is a major determinant of GWL, whereas information on the ET of PSF is limited. Therefore, we measured ET using the eddy covariance technique for 4-6 years between 2002 and 2009, including El Niño and La Niña events, at three sites in Central Kalimantan, Indonesia. The sites were different in disturbance degree: a PSF with little drainage (UF), a heavily drained PSF (DF), and a drained burnt ex-PSF (DB); GWL was significantly lowered at DF, especially in the dry season. The ET showed a clear seasonal variation with a peak in the mid-dry season and a large decrease in the late dry season, mainly following seasonal variation in net radiation (Rn ). The Rn drastically decreased with dense smoke from peat fires in the late dry season. Annual ET forced to close energy balance for 4 years was 1636 ± 53, 1553 ± 117, and 1374 ± 75 mm yr(-1) (mean ± 1 standard deviation), respectively, at UF, DF, and DB. The undrained PSF (UF) had high and rather stable annual ET, independently of El Niño and La Niña events, in comparison with other tropical rainforests. The minimum monthly-mean GWL explained 80% of interannual variation in ET for the forest sites (UF and DF); the positive relationship between ET and GWL indicates that drainage by a canal decreased ET at DF through lowering GWL. In addition, ET was decreased by 16% at DB in comparison with UF chiefly because of vegetation loss through fires. PMID:24912043

  1. Novel labeling technique illustrates transfer of 15N2 from Sphagnum moss to vascular plants via diazotrophic nitrogen fixation

    NASA Astrophysics Data System (ADS)

    Thorp, N. R.; Vile, M. A.; Wieder, R.

    2013-12-01

    We used 15N2 gas to trace nitrogen (N) from biological N2-fixation to vascular plant uptake in an Alberta bog in order to determine if neighboring bog plants acquire recently fixed N from diazotrophs associating with Sphagnum mosses. Recent evidence indicates high rates of N2-fixation in Sphagnum mosses of Alberta bogs (Vile et al. 2013). Our previous work has shown that mosses can assimilate fixed N from associated diazotrophs as evidenced by the high N content of mosses despite minimal inputs from atmospheric deposition, retranslocation, and N mineralization. Therefore, the potential exists for vascular plants to obtain N from ';leaky' tissues of live mosses, however, this phenomenon has not been tested previously. Here we document the potential for relatively rapid transfer to vascular plants of N fixed by Sphagnum moss-associated diazotrophs. We utilized the novel approach of incubating mosses in 15N2 to allow the process of diazotrophic N2-fixation to mechanistically provide the 15N label, which is subsequently transferred to Sphagnum mosses. The potential for vascular bog natives to tap this N was assessed by planting the vascular plants in the labeled moss. Sphagnum mosses (upper 3 cm of live plants) were incubated in the presence of 98 atom % 15N2 gas for 48 hours. Two vascular plants common to Alberta bogs; Picea mariana and Vaccinium oxycoccus were then placed in the labeled mosses, where the mosses served as the substrate. Tissue samples from these plants were collected at three time points during the incubation; prior to 15N2 exposure (to determine natural abundance 15N), and at one and two months after 15N2 exposure. Roots and leaves were separated and run separately on a mass spectrometer to determine 15N concentrations. Sphagnum moss capitula obtained N from N2-fixation (δ15N of -2.43 × 0.40, 122.76 × 23.78, 224.92 × 68.37, 143.74 × 54.38 prior to, immediately after, and at 1 and 2 months after exposure to 15N2, respectively). Nitrogen was

  2. Development of a Waste Water Regenerative System - Using Sphagnum Moss Ion-exchange

    NASA Astrophysics Data System (ADS)

    McKeon, M.; Wheeler, R.; Leahy, Jj

    The use of inexpensive, light weight and regenerative systems in an enclosed environment is of great importance to sustained existence in such habitats as the International Space Station, Moon or even Mars. Many systems exist which utilise various synthetic ion exchangers to complete the process of waste water clean-up. These systems do have a very good exchange rate for cations but a very low exchange rate for anions. They also have a maximum capacity before they need regeneration. This research proposes a natural alternative to these synthetic ion-exchangers that utilises one of natures greatest ion-exchangers, that of Sphagnum Moss. Sphagna can be predominantly found in the nutrient poor environment of Raised Bogs, a type of isolated wetland with characteristic low pH and little interaction with the surrounding water table. All nutrients come from precipitation. The sphagna have developed as the bog's sponges, soaking up all available nutrients (both cation & anion) from the precipitation and eventually distributing them to the surrounding flora and fauna, through the water. The goal of this research is to use this ability in the processing of waste water from systems similar to isolated microgravity environments, to produce clean water for reuse in these environments. The nutrients taken up by the sphagna will also be utilised as a growth medium for cultivar growth, such as those selected for hydroponics' systems.

  3. 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

  4. Sulfur contents of peats at the confluence of carbonate and peat-forming depositional systems, southeastern Florida

    SciTech Connect

    Cohen, A.D. ); Davies, T.D. ); Spackman, W. )

    1993-08-01

    Complex stratigraphic and compositional relationships have been reported by others at sites where coal beds are laterally in contact with marine carbonates (such as in the southern portion of the Illinois basin). These basin edges are important in that they may (1) represent sites of active coal mining, (2) contain important clues as to the development of the basin, and (3) be sources of the dispersed terrestrial organics encountered in nearby marine rocks. This study was undertaken to investigate peat/carbonate relationships in a modern setting, with initial research on sulfur contents relative to stratigraphic/petrographic conditions. Thirty-eight cores were taken along northwest-southeast transects from the mainland to Florida Bay. The most inland cores consist entirely of peat, representing transgression of marine types (mangrove) over freshwater types. Toward the carbonate-rich bay, a more complex stratigraphy exists. Marine carbonates and peats interfinger, with erosional contacts indicating that parts of the peat sequence are missing. At the coastline, most of the peat is replaced by marine carbonate except for thin (1-10 cm) basal (usually overlain by marine carbonates), with the best preserved ranges from 0.6 to 5.0% (dry) at the most inland sites, 2.4 to 7.8% near the coastline, and 1.5 to 5.9% in bay sediments. Total sulfur is higher in marine than freshwater peats, but freshwater peats overlain by marine peats are enriched in sulfur. Freshwater peats beneath marine carbonates are relatively low in sulfur, but are higher if the peat is overlain by a marine peat before being overlain by the carbonate.

  5. Peat resource estimation in South Carolina. Final report, Year 2

    SciTech Connect

    Holmes, M.; Andrejko, M.; Corvinus, D.; Tisdale, M.

    1982-01-01

    South Carolina has few indigenous energy resources. Most widely known and utilized are hydropower, wood, and solar. Peat is a material composed of partially decomposed organic matter that, after burial for long periods of time, may eventually become coal. Peat is utilized as an energy resource for the production of electricity and for home heating in Europe and the Soviet Union. There are peat deposits in South Carolina, but peat has never been used as an energy resource within the state. This report presents the results of the two years of a planned four-year study of the quantity and energy potential of peat in South Carolina. In this year's survey two activities were undertaken. The first was to visit highly probable peat deposits to confirm the presence of fuel-grade peat. The second was to survey and characterize in more detail the areas judged to be of highest potential as major resources. The factors carrying the greatest weight in our determination of priority areas were: (1) a description of peat deposits in the scientific literature or from discussions with state and federal soil scientists; (2) mention of organic soils on soil maps or in the literature; and (3) information from farmers and other local citizens.

  6. Holocene palaeohydrological history of the Tǎul Muced peat bog (Northern Carpathians, Romania) based on testate amoebae (Protozoa) and plant macrofossils

    NASA Astrophysics Data System (ADS)

    Cosmin Diaconu, Andrei; Feurdean, Angelica; Lamentowicz, Mariusz; Gałka, Mariusz; Tanţǎu, Ioan

    2016-04-01

    Knowledge of past local vs. regional hydro-climate variability is a priority in climate research. This is because ecosystems and human depend on local climatic conditions and the magnitude of these climate changes is more variable at local and regional rather than at global scales. Ombrotrophic bogs are highly suitable for hydro-climate reconstructions as they are entirely dependent on the water from precipitation. We used stratigraphy, radiocarbon dating, testate amoebae (TA) and plant macrofossils on a peat profile from an ombrotrophic bog (Tǎul Muced) located in the Biosphere Reserve of the Rodna National Park Romania. We performed quantitative reconstruction of the depth to water table (DWT) and pH over the last 8000 years in a continental area of CE Europe. We identified six main stages in the development of the bog based on changes in TA assemblages in time. Wet conditions and pH between 2 and 4.5 were recorded between 4600-2750 and 1300-400 cal. yr BP, by the occurrence of Archerella flavum, Amphitrema wrightianum and Hyalosphenia papilio. This was associated to a local vegetation primarily composed of Sphagnum magellanicum and S. angustifolium. Dry stages and pH of 2.5 to 5 were inferred between 7550-4600, 2750-1300 and -50 cal. yr BP, by the dominance of Nebela militaris, Difflugia pulex and Phryganella acropodia. These overall dry conditions were also connected with increased abundance of Eriophorum vaginatum. The period between 400 and -50 cal. yr BP was characterized by a rapid shift from dry to wet conditions on the surface of the bog. Vegetation shifted from Sphagnum magellanicum to Sphagnum russowii dominated community. Our reconstruction remains in relatively good agreement with other palaeohydrological records from Central Eastern Europe. However, it shows contrasting conditions to others particularly with records from NW Europe. The valuable information regarding bog hydrology offered by our record puts an accent on the need of more regional TA

  7. Environmental Controls over Peat Accumulation in Arctic Alaska

    NASA Astrophysics Data System (ADS)

    Baughman, C. A.; Mann, D. H.; Heiser, P. A.; Kunz, M. L.

    2012-12-01

    Wide spread accumulation of peat (paludification) began on Alaska's North Slope during the Pleistocene/Holocene transition starting ca. 12,000 14C years ago and established this region as a carbon sink. Its status as a C sink is in question today because of rapid climate change. Our project's focus is on the relationship between peat, microclimate, and topography in a portion of the Arctic Foothills 300-350 km south of Point Barrow on the northern flank of the Brooks Range. Our objectives are 1) Quantify how varying microclimate factors found along a climosequence determine the thickness of the thin surface peats (<50 cm) that have developed during the Holocene; 2) Estimate peat accumulation rates on level, initially well-drained geomorphic surfaces using a 3,000 year old chronosequence on river point bars; 3) Quantify how peat accumulation affects soil temperature regimes; 4) Develop a GIS-based peat-prediction model for a 50 km2 study area and estimate this area's pool of standing carbon. We used a combination of remotely sensed data, field measurements, and a GIS to gather data regarding slope, aspect, elevation, near-ground temperature, soil moisture, temperature at the organic/mineral horizon interface, solar radiation, upslope drainage area, and lastly, peat thickness. Peat is defined here as any near-surface soil horizon containing >25% organic carbon by volume. We employ statistical analyses to examine how each factor independently influences peat thickness and what suite of factors best explains peat distribution and thickness across the landscape. Results show a significant inverse relationship (R2 = 0.27, p-value <<.001) between slope and peat thickness, with an increase in steepness accompanying a decrease in peat thickness. There is a less significant relationship (R2 = 0.03, p-value = .02) between aspect and peat thickness. There is a significant positive relationship (R2 = 0.81, P-value <<.001) between peat thickness and July active layer thickness

  8. Possibilities for detailed dating of peat bog deposits

    SciTech Connect

    Punning, J.; Ilomets, M.; Koff, T. )

    1993-01-01

    Geochemical and palynological data as well as radiocarbon dating were used to study the peat bog deposits in Niinsarre bog, northeast Estonia. The aim of this study was to establish criteria for determining a detailed chronology, which is important, for example, in studying paleoevents and historical monitoring. In some cases, they can use cumulative pollen data, as well as cumulative chemical and peat bulk density data. Material was gathered for [sup 14]C dating from three parallel samples taken from cores ca. 10--20 cm apart using a Russian peat sampler. Samples for peat bulk density, palynological and chemical measurements were taken from the same cores. To measure peat bulk density, the authors used a continuous sampling method. Sampling frequency was calculated to cover layers formed over 50 yr.

  9. Aerobic and microaerophilic actinomycetes of typical agropeat and peat soils

    NASA Astrophysics Data System (ADS)

    Zenova, G. M.; Gryadunova, A. A.; Pozdnyakov, A. I.; Zvyagintsev, D. G.

    2008-02-01

    A high number (from tens of thousands to millions of CFU/g of soil) of actinomycetes and a high diversity of genera were found in typical peat and agropeat soils. Agricultural use increases the number and diversity of the actinomycete complexes of the peat soils. In the peat soils, the actinomycete complex is represented by eight genera: Streptomyces, Micromonospora, Streptosporangium, Actinomadura, Microbispora, Saccharopolyspora, Saccharomonospora, and Microtetraspora. A considerable share of sporangial forms in the actinomycete complex of the peat soils not characteristic of the zonal soils was revealed. The number of actinomycetes that develop under aerobic conditions is smaller by 10-100 times than that of aerobic forms in the peat soils. Among the soil actinomycetes of the genera Streptomyces, Micromonospora, Streptosporangium, Actinomadura, Microbispora, and Microtetraspora, the microaerophilic forms were found; among the Saccharopolyspora and Saccharomonospora, no microaerophilic representatives were revealed.

  10. Mitigating Settlement of Structures founded on Peat

    NASA Astrophysics Data System (ADS)

    Wijeyesekera, D. C.; Numbikannu, L.; Ismail, T. N. H. T.; Bakar, I.

    2016-07-01

    Observations made of two common failures of structures founded on peat/organic soil in Johor, Malaysia is presented. Critical evaluation of current lightweight fill technology to mitigate such settlement is also discussed. Lightweight technology, such as Expanded Polystyrene (EPS), has been used in construction on soft yielding ground for decades. Regrettably, some published information of EPS failures to perform on construction sites are also cited in this paper. This paper outlines some concepts leading to the development of an alternative innovative lightweight fill is that the idealised cellular structure of the GCM permit free flow of water and complemented by the mat structure which evens out any differential settlement A further highlight of this paper is the monitoring of the field performance of this lightweight fill (GCM) as a feasible alternative to fill weight reduction on yielding ground.. Hence, a prime research objective was to compare the fill settlements observed with 1m high fill of surcharge loading on peat ground (comparison of the case of using a partial 0.6m high GCM and that of a total of 1m of conventional sand backfill).

  11. Peatland Carbon Dynamics on the North Slope of Alaska During the Holocene: The Role of Climate, Sea Ice, and Buried Peat

    NASA Astrophysics Data System (ADS)

    Yu, Zicheng; Massa, Charly; Cleary, Kathleen; Jones, Benjamin; Grosse, Guido

    2014-05-01

    Our recent and ongoing data syntheses indicate that peatlands accumulated more carbon (C) during past warm climate intervals in the circum-Arctic region, including Alaska. In particular, peak C accumulations have been observed during the Holocene Thermal Maximum (HTM) in the early Holocene when summer insolation was higher. However, we do not know the regional patterns and impacts of sea-ice change on Holocene peat C accumulation, especially around the Arctic Ocean where increased vegetation productivity has already been linked to sea ice declines in recent decades. Here we review Holocene peatland and tundra C accumulation records on the North Slope, along with our preliminary results, to investigate spatiotemporal pattern of C accumulation and the possible role of sea-ice change. As in many other northern high-latitude regions, most peatlands on the North Slope initiated in the early Holocene. Several discontinuous and low-resolution peat accumulation records from the region appear to show high accumulation rates or high C content in the early Holocene. In addition, we note that many peatlands that existed during the earlier Holocene on the North Slope have disappeared and are presently covered by mineral soils under tundra or eolian sandy deposits, indicating that current peatland extent is only a fraction of early Holocene extent. In contrast to highest C accumulation rates in the early Holocene, our preliminary results from a 70-cm-long peat core (lat. 70.71 N; long. 153.87 W) from northwest Teshekpuk Lake, near the Teshekpuk Lake Observatory on the Arctic Coastal Plain, about 10 km from the Arctic Ocean, shows a very different pattern. The highest C accumulation of 12.7 gC/m2/yr is observed after 2.9 ka, much higher than the rate of 3.8 gC/m2/yr at 8.1-2.9 ka. Furthermore, the period with high C rates after 2.9 ka at this site was dominated by well-preserved peat mosses (Sphagnum) and with abundant leaf fragments, likely from dwarf birch (Betula nana). This

  12. Impact of mesh tracks and low-ground-pressure vehicle use on blanket peat hydrology

    NASA Astrophysics Data System (ADS)

    McKendrick-Smith, Kathryn; Holden, Joseph; Parry, Lauren

    2016-04-01

    Peatlands are subject to multiple uses including drainage, farming and recreation. Low-ground-pressure vehicle access is desirable by land owners and tracks facilitate access. However, there is concern that such activity may impact peat hydrology and so granting permission for track installation has been problematic, particularly without evidence for decision-making. We present the first comprehensive study of mesh track and low-ground-pressure vehicle impacts on peatland hydrology. In the sub-arctic oceanic climate of the Moor House World Biosphere Reserve in the North Pennines, UK, a 1.5 km long experimental track was installed to investigate hydrological impacts. Surface vegetation was cut and the plastic mesh track pinned into the peat surface. The experimental track was split into 7 treatments, designed to reflect typical track usage (0 - 5 vehicle passes per week) and varying vehicle weight. The greatest hydrological impacts were expected for sections of track subject to more frequent vehicle use and in close proximity to the track. In total 554 dipwells (including 15 automated recording at 15-min intervals) were monitored for water-table depth, positioned to capture potential spatial variability in response. Before track installation, samples for vertical and lateral hydraulic conductivity (Ks) analysis (using the modified cube method) were taken at 0-10 cm depth from a frequently driven treatment (n = 15), an infrequently driven treatment (0.5 passes per week) (n = 15) and a control site with no track/driving (n = 15). The test was repeated after 16 months of track use. We present a spatially and temporally rich water-table dataset from the study site showing how the impacts of the track on water table are spatially highly variable. Water-table depths across the site were shallow, typically within the upper 10 cm of the peat profile for > 75% of the time. We show that mesh track and low-ground-pressure vehicle impacts on water-table depth were small except

  13. Interactions between Nitrogen Fixation and Methane Cycling in Northern Minnesota Peat Bogs

    NASA Astrophysics Data System (ADS)

    Warren, M. J.; Gaby, J. C.; Lin, X.; Morton, P. L.; Kostka, J. E.; Glass, J. B.

    2014-12-01

    Peatlands cover only 3% of the Earth's surface, yet store a third of soil carbon. Increasing global temperatures have the potential to change peatlands from a net sink to a net source of atmospheric carbon. N is a limiting nutrient in oligotrophic Sphagnum-dominated peatlands and biological N2 fixation likely supplies a significant but unknown fraction of N inputs. Moreover, environmental controls on diazotrophic community composition in N-limited peatlands are poorly constrained. Thus, improved understanding of feedbacks between the CH4 and N cycles is critical for predicting future changes to CH4 flux from peat bogs. We coupled measurements of N2 fixation activity measured by the acetylene (C2H2) reduction assay (ARA) with molecular analyses of expression and diversity of nifH genes encoding the molybdenum (Mo)-containing nitrogenase from two peat bogs in the Marcell Experimental Forest, Minnesota, USA. The top 10 cm of peat was sampled from the high CH4 flux S1 bog and the low CH4 flux Zim bog in April and June 2014. Despite similar N concentrations in the top 10 cm of both bogs (0.5-1.0 μM NO2-+NO3- and 2-3 μM NH4+), the S1 bog displayed variable ARA activity (1-100 nmol C2H4 h-1 g-1) whereas the Zim bog had consistently low ARA activity (<1 nmol C2H4 h-1 g-1). Highest ARA activity was measured in June from S1 bog hollows with higher moisture content incubated without O2 in the light (20-100 nmol C2H4 h-1 g-1). Dissolved Fe (1-25 μM) was higher in hollow vs. hummock samples, and at S1 vs. Zim bog, while dissolved V (4-14 nM) was consistently higher than Mo (1-4 nM), suggesting that alternative V or Fe-containing nitrogenases might be present in these bogs. In contrast, Cu, an essential micronutrient for aerobic methanotrophs, was higher in hummocks (25-48 nM) than hollows (6-17 nM). The facultative methanotroph Methylocella was the dominant diazotroph in the S1 bog based on high throughput next generation sequencing of nifH cDNA amplicons. Given previous

  14. Laboratory evaporation experiments in undisturbed peat columns for determining peat soil hydraulic properties

    NASA Astrophysics Data System (ADS)

    Dettmann, U.; Frahm, E.; Bechtold, M.

    2013-12-01

    Knowledge about hydraulic properties of organic soils is crucial for the interpretation of the hydrological situation in peatlands. This in turn is the basis for designing optimal rewetting strategies, for assessing the current and future climatic water balance and for quantifying greenhouse gas emissions of CO2, CH4 and N2O, which are strongly controlled by the depth of the peat water table. In contrast to mineral soils, the hydraulic properties of organic soils differ in several aspects. Due to the high amount of organic components, strong heterogeneity, and shrinkage and swelling of peat, accompanied by changing soil volume and bulk density, the applicability of standard hydraulic functions developed for mineral soils for describing peat soil moisture dynamics is often questioned. Hence, the objective of this study was to investigate the applicability of the commonly applied van Genuchten-Mualem (VGM) parameterization and to evaluate model errors for various peat types. Laboratory column experiments with undisturbed peat soils (diameter: 30 cm, height: 20 cm) from 5 different peatlands in Germany were conducted. In numerical simulations using HYDRUS-1D the experimental data were used for an inverse estimation of the soil hydraulic parameters. Using the VGM parameterization, the model errors between observed and measured pressure heads were quantified with a root mean square error (RMSE) of 20 - 65 cm. The RMSE increased for soils with higher organic carbon content and higher porosity. Optimizing the VGM 'tortuosity' parameter (τ) instead of fixing it to its default of 0.5 strongly reduced the RMSE, especially for the soils that showed high pressure head gradients during the experiment. Due to the fact, that very negative pressure heads in peatlands occur rarely, we reduced the range of pressured heads in the inversion to a 'field-relevant' range from 0 to -200 cm which strongly reduced the RMSE to 6 - 12 cm and makes the VGM parameterization applicable for all

  15. Willow firing in retrofitted Irish peat plant

    SciTech Connect

    Broek, R. van den; Faaij, A.; Kent, T.

    1995-11-01

    Interest in biomass electricity in Ireland is being re-awakened by environmental concerns about CO{sub 2} emissions from power generation and the potential of biomass production to provide an alternative agricultural enterprise. The technical and economical feasibility of wood-fuelled power production using willow from energy farming in existing peat-fired plants in Ireland is being studied within the framework of the EU JOULE II+ programme. These options are compared with new combustion plants and a biomass integrated gasifier with combined cycle (BIG/CC). Background studies supplied data for yields of willow farming, establishment of willow plantations, harvesting methods, logistics and costs and efficiencies for different retrofit options at Irish peat plants. All technologies considered are currently available or are expected to be available in the near future. Neither agricultural subsidies nor possible CO{sub 2} taxes have been included. In the least cost supply scenario storage and chipping of wood is done at the power station. In this case wood is only stored in the form of sticks and wood harvested by a chips harvester is supplied to the plant directly during the harvesting season. Fuel costs at the plant gate were estimated between 3.3 and 11 EGU/GJ{sub LHV}. This wide range resulted in a wide range of kWh costs. For the lowest cost option they ranged between 5.4 and 15 ECUcents/kWh. The cheapest proven retrofit option is the conversion of the existing milled peat Lanesborough unit 3 into a bubbling fluidized bed with kWh costs ranging from 5.6 up to 16 ECUcents/kWh. For this plant, costs per tonne of avoided CO{sub 2} emissions varied between 1 and 70 ECU. It is noteworthy that the kWh costs for all options considered were very close. Especially in the high costs scenario a BIG/CC appeared to have lower kWh cost than all biomass combustion plants. Mainly for the retrofitted plants the fuel costs were by far the largest kWh cost component.

  16. Peat resources of Maine. Volume 2. Penobscot County

    SciTech Connect

    Cameron, C.C.; Mullen, M.K.; Lepage, C.A.; Anderson, W.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 acres 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.

  17. Age models for peat deposits on the basis of coupled lead-210 and radiocarbon data.

    NASA Astrophysics Data System (ADS)

    Piotrowska, Natalia; de Vleeschouwer, François; Sikorski, Jarosław; Sensuła, Barbara; Michczyński, Adam; Fiałkiewicz-Kozieł, Barbara; Palowski, Bernard

    2010-05-01

    The study presents three examples of age-model construction based on the results of 210Pb and 14C dating methods applied to peat deposits. The three sites are ombrotrophic peat bogs: the Misten (Belgium), Slowinskie Bloto (N Poland) and Puscizna Mala (S Poland). All sites have been subjected to multiproxy studies aimed at reconstructing paleoenvironment and human activity, covering the last 1500, 1300 and 1800 years, respectively (De Vleeschouwer et al. 2009A, 2009B, in prep., Fialkiewicz-Koziel, ongoing PhD). A detailed comparison between 210Pb and post-bomb 14C results in the Misten bog has also been carried out by Piotrowska et al. (2009). In all cores, the 210Pb activity was calculated using 210Po and 208Po activities after acid-extraction from bulk samples, subsequent deposition on silver discs and measurements by alpha spectrometry. Unsupported 210Pb was detected until 35cm in Slowinskie Bloto, 15cm in the Misten and 19cm in Puscizna Mala. Constant Rate of Supply (CRS) model was then applied to compute ages of each 1-cm core interval. For the Misten and Slowinskie Bloto, radiocarbon measurements were performed on selected aboveground plant macrofossils, mainly Sphagnum spp. or Calluna vulgaris, Erica tetralix, and Andromeda polyfolia. Radiocarbon ages were determined using accelerator mass spectrometry (AMS) after acid-alkali-acid wash, combustion, purification of carbon dioxide and graphitisation. For Puscizna Mala bulk samples were dated after chemical preparation of benzene for liquid scintillation counting (LSC) or CO2 for gas proportional counting (GPC). Radiocarbon calibration was undertaken using the Intcal04 calibration curve and OxCal 4 software. As a priori information the 210Pb-derived ages were used in a P_Sequence model (Bronk Ramsey, 2008). A number of dates characterized by low agreement with stratigraphical order had to be considered as outliers and rejected from the final age model. For building a continuous age models a non-linear approach

  18. 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.

  19. Heavy metal removal using peat/wetland treatment

    SciTech Connect

    Murawski, S.

    1994-12-31

    The purpose of this paper is to present an overview of the mechanisms and application of a peat/wetland treatment system for heavy metal removal from wastewater. The mechanisms involved in the removal of heavy metals are complex and difficult to predict, however, peat has been proven to be an effective medium to remove metals. The successful design of a peat/wetland treatment system for acid mine drainage is presented to emphasize the low cost and minimal maintenance involved in this passive metal removal technique.

  20. Peat pyrolysis and the analytical semi-empirical model

    SciTech Connect

    Feng, J.; Green, A.E.S.

    2007-07-01

    Pyrolysis of peat could convert this material into useful fuels and valuable hydrocarbons. A study of peat pyrolysis can also serve as a useful bridge between studies of coal pyrolysis and biomass pyrolysis. Using an analytical model of pyrolysis that has previously been applied to biomass and to coal, we present here the results of applications of this model to a representative peat. The analysis suggests means of organizing and processing rate and yield data that should be useful in applications of pyrolysis for the production of fuels and chemicals.

  1. Comparison of heavy metal immobilization in contaminated soils amended with peat moss and peat moss-derived biochar.

    PubMed

    Park, Jin Hee; Lee, Seul-Ji; Lee, Myoung-Eun; Chung, Jae Woo

    2016-04-20

    There have been contradictory viewpoints whether soil amendments immobilize or mobilize heavy metals. Therefore, this study evaluated the mobility and bioavailability of Pb, Cu, and Cd in contaminated soil (1218 mg Pb per kg, 63.2 mg Cu per kg, 2.8 mg Cd per kg) amended with peat moss (0.22, 0.43, and 1.29% carbon ratio) and peat moss-derived biochar (0.38, 0.75, and 2.26% carbon ratio) at 0.5, 1, 3% levels. The more peat moss added, the stronger both mobility and bioavailability of Pb, Cu, and Cd would be. In contrast, the addition of peat moss-derived biochar significantly reduced both mobility and bioavailability of heavy metals through the coordination of metal electrons to C[double bond, length as m-dash]C (π-electron) bonds and increased pH. Maximum immobilization was observed in 3% peat moss-derived biochar treatment after 10 days of incubation, which was measured at 97.8%, 100%, and 77.2% for Pb, Cu, and Cd, respectively. Since peat moss and peat moss-derived biochar showed conflicting effectiveness in mobility and bioavailability of heavy metals, soil amendments should be carefully applied to soils for remediation purposes. PMID:27055368

  2. Geochemistry and radiometric dating of a Middle Pleistocene peat

    SciTech Connect

    Rowe, P.J.; Atkinson, T.C.; Richards, D.A.; Bottrell, S.H.; Cliff, R.A.

    1997-10-01

    Uranium, lead, and sulphur data for a Middle Pleistocene interglacial peat deposit from Norfolk, UK, suggest that uptake of these elements was synchronous and confined to a single early diagenetic episode, probably coeval with peat formation. Sulphur isotope data indicate that reducing conditions have been maintained within the deposit throughout its history. Both uranium and lead concentration profiles show a marked discontinuity near the middle of the bed, probably indicating an environmental change, possibly emergence. The lead isotope data are compatible with a single lead component below the discontinuity and two components above. Groundwater is thought to be the dominant source of lead with an additional airfall component present in the upper peat. The uranium and lead concentration profiles below the discontinuity and the sulfur isotope profile throughout the peat support the view that these elements were sequestered from upwelling groundwaters. 35 refs., 9 figs., 3 tabs.

  3. 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).

  4. 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.

  5. Climate variability and long-term expansion of peat lands in Arctic Norway during the late Pliocene (ODP Site 642, Norwegian Sea)

    NASA Astrophysics Data System (ADS)

    Panitz, Sina; Salzmann, Ulrich; Risebrobakken, Bjorg; De Schepper, Stijn; Pound, Matthew; Bachem, Paul

    2016-04-01

    We present the first high resolution reconstruction of vegetation and climate change in northern Norway between 3.6-3.14 Ma based on pollen assemblages in the marine sediments of ODP Hole 642B, Norwegian Sea (67°N). During the late Pliocene vegetation alternated between cool temperate forests during warmer-than-present intervals and boreal forest similar to today during cooler intervals. The northern boundary of the deciduous to mixed forest zone was displaced at least 4-8° further north and warmest month temperatures were 6-14.5°C higher than present during warm phases. Diverse cool temperate deciduous to mixed forests grew under warm climatic conditions in the lowlands of the Scandinavian mountains during the earliest late Pliocene (c. 3.6-3.47 Ma). A distinct cooling event at c. 3.47 Ma led to the predominance of boreal forest and the development of open, low alpine environments. The cooling culminated around 3.3 Ma, coinciding with Marine Oxygen Isotope Stage (MIS) M2. After c. 3.29 Ma a high variability of climate is indicated by the repeated expansion of forests and peat lands during warmer and cooler periods, respectively. Climate progressively cooled after 3.18 Ma, resembling climatic conditions during MIS M2. A long-term cooling is expressed by an expansion of Sphagnum peat lands that potentially contributed to the decline in atmospheric CO2-concentration at the end of the Piacenzian warm period. Correlations with other Northern Hemisphere records suggest hemisphere-wide effects of climate changes. Late Pliocene vegetation changes will be compared to alkenone-based sea surface temperature reconstructions and dinoflagellate cyst assemblage changes for ODP Hole 642B.

  6. CO2 exchange following peat extraction - a comparison of two paired restored/unrestored peatlands

    NASA Astrophysics Data System (ADS)

    Strachan, Ian; Strack, Maria; Pelletier, Luc; Nugent, Kelly; Rankin, Tracy

    2016-04-01

    Peat extraction is an important industry in parts of Canada and elsewhere globally. The resulting disturbance from drainage and vacuum-harvesting is mitigated through best practices which now incorporate restoration intended to return the peatland's biodiversity and greenhouse gas (GHG) exchange to that resembling the pre-disturbance state. We examine the net ecosystem exchange of CO2 (NEE) in two sets of paired peatlands. Within each pair, the extraction year was the same and the sites were treated identically post-extraction in terms of management (blocking drains or leveling as applicable). The first pair is located in the vicinity of Rivière-du-Loup, Québec, Canada and were harvested in 1980. The Bois-des-Bel (BDB) site was restored in 1999 following the methods of Quinty and Rochefort (2003). GHG fluxes have been studied at various points since restoration (e.g. Strack and Zuback, 2013) largely using chamber measurements. The site now hosts a thriving bog ecosystem with Sphagnum, Eriophorum and shrub communities. A site 30 km away near Saint-Alexandre de Kamouraska (SAK) was managed post-harvest as BDB with drains blocked but was left unrestored and now has only sparse Eriophorum with invasive species. The second pair of peatlands represents a newly extracted site near Seba Beach, Alberta, Canada. One field was restored (SBR) in autumn 2012 as per the Québec sites but with ditches infilled when the fields were levelled while the other (SBU) was left unrestored. In the summer of 2013, eddy covariance towers were installed at each location and measured NEE continuously at 10Hz throughout the subsequent periods. BDB and SBR remain operational today while SBU was removed in fall 2014 and SAK in fall 2015. In this presentation, we will focus on the coincident years of operation. After 15 years, BDB has measured NEE in the range of that observed at natural peatlands. A summer sink and winter release lead to annual uptake of CO2. At SAK, the lack of establishment

  7. 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

  8. Evaluation of the VIIRS Land Algorithms at Land PEATE

    NASA Technical Reports Server (NTRS)

    Wolfe, Robert E.; Devadiga, Sadashiva; Ye, Gang; Masuoka, Edward J.; Schweiss, Robert J.

    2010-01-01

    The Land Product Evaluation and Algorithm Testing Element (Land PEATE), a component of the Science Data Segment of the National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project (NPP), is being developed at the NASA Goddard Space Flight Center (GSFC). The primary task of the Land PEATE is to assess the quality of the Visible Infrared Imaging Radiometer Suite (VIIRS) Land data products made by the Interface Data Processing System (IDPS) using the Operational (OPS) Code during the NPP era and to recommend improvements to the algorithms in the IDPS OPS code. The Land PEATE uses a version of the MODIS Adaptive Processing System (MODAPS), NPPDAPS, that has been modified to produce products from the IDPS OPS code and software provided by the VIIRS Science Team, and uses the MODIS Land Data Operational Product Evaluation (LDOPE) team for evaluation of the data records generated by the NPPDAPS. Land PEATE evaluates the algorithms by comparing data products generated using different versions of the algorithm and also by comparing to heritage products generated from different instrument such as MODIS using various quality assessment tools developed at LDOPE. This paper describes the Land PEATE system and some of the approaches used by the Land PEATE for evaluating the VIIRS Land algorithms during the pre-launch period of the NPP mission and the proposed plan for long term monitoring of the quality of the VIIRS Land products post-launch.

  9. Peat resources of North Carolina. Quarterly progress report

    SciTech Connect

    Ingram, R.L.; Otte, L.J.

    1980-07-01

    Although the work on North Carolina peat deposits is far from complete, a preliminary estimate of the amount of peat was made. Table 1 has the listing of all three types of deposits, Pocosin, River Flood Plain and Carolina Bays, and their description such as area, weight, thickness and quality estimation. Work on the peats of Light Ground Pocosin has been completed and the final report will be distributed soon. Work is continuing on the three largest Pocosin deposits; East Dismal Swamp (Dare Peninsula), Dismal Swamp, and Croatan Forest. As for river deposits, reconnaissance work indicates that peat is to be found along the lower floodplains of the Chowan, Roanoke, and Cape Fear Rivers. The quality (ash content) is much more variable than for the pocosin peats. There are approximately 2100 Carolina Bays deposits, over 800 ft long. A map is provided showing their distribution. Preliminary work shows that most of these bays contain good peat up to a maximum thickness of 15 ft.

  10. 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.

  11. Effect of peat on physicomechanical properties of cemented brick.

    PubMed

    Islam, Syed Mofachirul; Hashim, Roslan; Islam, A B M Saiful; 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

  12. Mercury methylation in Sphagnum moss mats and its association with sulfate-reducing bacteria in an acidic Adirondack forest lake wetland.

    PubMed

    Yu, Ri-Qing; Adatto, Isaac; Montesdeoca, Mario R; Driscoll, Charles T; Hines, Mark E; Barkay, Tamar

    2010-12-01

    Processes leading to the bioaccumulation of methylmercury (MeHg) in northern wetlands are largely unknown. We have studied various ecological niches within a remote, acidic forested lake ecosystem in the southwestern Adirondacks, NY, to discover that mats comprised of Sphagnum moss were a hot spot for mercury (Hg) and MeHg accumulation (190.5 and 18.6 ng g⁻¹ dw, respectively). Furthermore, significantly higher potential methylation rates were measured in Sphagnum mats as compared with other sites within Sunday Lake's ecosystem. Although MPN estimates showed a low biomass of sulfate-reducing bacteria (SRB), 2.8 × 10⁴ cells mL⁻¹ in mat samples, evidence consisting of (1) a twofold stimulation of potential methylation by the addition of sulfate, (2) a significant decrease in Hg methylation in the presence of the sulfate reduction inhibitor molybdate, and (3) presence of dsrAB-like genes in mat DNA extracts, suggested that SRB were involved in Hg methylation. Sequencing of dsrB genes indicated that novel SRB, incomplete oxidizers including Desulfobulbus spp. and Desulfovibrio spp., and syntrophs dominated the sulfate-reducing guild in the Sphagnum moss mat. Sphagnum, a bryophyte dominating boreal peatlands, and its associated microbial communities appear to play an important role in the production and accumulation of MeHg in high-latitude ecosystems. PMID:20955196

  13. Impact of catchment degree on peat properties in peat deposits of eutrophic bog

    NASA Astrophysics Data System (ADS)

    Inisheva, L. I.; Golubina, O. A.; Rodikova, A. V.; Shinkeeva, N. A.; Bubina, A. B.

    2010-05-01

    Fundamental works of many investigators show that according to the biophysical properties peat deposit (PD) is divided into 2 layers: active and inert. It is interesting to analyze the supposed changes in PD of eutrophic bog according to different data (physical, chemical and biological). The researches were carried out at two plots of one bog (points 1 and 2, positions 56° 21' NL, 84° 47' EL, Russia, Siberia). Agricultural afforestation (pine planting) was made at one of them (point 2) 60 years ago. Now this plot is absolutely identical in ground cover to 1 point, but other conditions are significantly changed. In spring bog water level is at the depth of 20cm at 2 point (at 1 point it is near water face), it lows up to 53 cm during summer time (at 1 point - up to 37 cm). According to redox conditions zone of anoxic-oxic conditions reaches meter depth at 2 points. PDs don't significantly differ in activity of ammonifiers but in activity of cellulose-lytic aerobic microflora it follows that it is more active at 2 point in PD active layer. In spite of good aeration, more favorable conditions were created also for anaerobic cellulose-fermenting microflora in PD of 2 point in comparison with 1 one. Activity analysis of denitrifying agents and microflora of other physiological groups also showed high activity of biota at the plot with afforestation amelioration. This fact was confirmed by high coefficient of mineralization. Time of drainage effect created by afforestation amelioration influenced group composition of peat organic matter which builds up PD of examined plots. According to fractional and group composition data fracture of hard-to-hydrolyze organic matters decreased during the process of microflora activating at the plot with afforestation amelioration but FA content increased. Fractional composition of nitrogen showed that content of mineral nitrogen compounds definitely increased. Thus, 60 years of surface drainage influenced composition change of peat

  14. Nonphytotoxic Aluminum-Peat Complexes Suppress Phytophthora parasitica.

    PubMed

    Fichtner, E J; Hesterberg, D L; Shew, H D

    2001-11-01

    ABSTRACT Amendment of peat-based potting media with Al(2)(SO(4))(3) suppresses damping-off of Vinca (Catharanthus roseus) caused by Phytophthora parasitica. The species of aluminum (Al) responsible for disease suppression have not been identified. The objective of this study was to determine the effects of amount and pH of Al(2)(SO(4))(3) amendment solutions on survival of P. parasitica. In separate experiments, peat was amended with Al(2)(SO(4))(3) solutions adjusted to pH 4 or 6 at either 0.0158 or 0.0079 g of Al per gram of peat. Amended peat was placed in Büchner funnels maintained at -2.5 kPa matric potential. Peat was infested with P. parasitica by placing zero, two, or five colonized Vinca leaf disks in each funnel, and 15 Vinca seeds were placed in each funnel. After 24 h, the matric potential was brought to 0 kPa to induce zoospore release and returned to -2.5 kPa after 24 h. Pathogen populations and stand counts were assessed after 2-week incubation. Al amendment solutions at both pH 4 and 6 reduced pathogen populations at 0.0158 g of Al per gram of peat. Solutions at pH 4 reduced pathogen populations by more than 90% at both inoculum levels; amendment solutions at pH 6 reduced populations by 95% at the low inoculum level and 65% at the high inoculum level. The prevalence of Al(OH)(2)(+) in peat amended with Al(2)(SO(4))(3) solution at pH 6 suggests that ions other than Al(3+) may be responsible for pathogen suppression. Based on the difference in chemical conditions of Al-amended peat and suppressive mineral soils, the mechanism of Al-mediated suppression of plant pathogens is speculated to be different in the two systems. Peat containing Al-peat complexes was chemically suppressive to P. parasitica and may confer Al-mediated suppression of plant pathogens with a nonphytotoxic form of Al. PMID:18943446

  15. Global peat erosion risk assessment for the 21st Century

    NASA Astrophysics Data System (ADS)

    Li, Pengfei; Irvine, Brian; Holden, Joseph

    2015-04-01

    Many peatlands across the world are suffering from degradation and erosion exacerbated by human influences. Blanket peat erosion has adverse impacts on terrestrial and aquatic habitats, reservoir capacity and water quality, and also leads to accelerated carbon release. Bioclimatic modelling suggests that some areas, which are currently suitable for active peat growth, may be no longer under a climate supporting the accumulation of peat by the end of the century. Peat erosion in these marginal regions is thus more likely. A recently developed blanket peat erosion model, PESERA-PEAT, was established through significantly modifying the grid version of the Pan-European Soil Erosion Assessment model (PESERA-GRID) to explicitly include the freeze-thaw and desiccation processes, which appear to be the crucial drivers of peat erosion, and typical land management practices in blanket peatlands such as artificial drainage, grazing and managed burning. Freeze-thaw and desiccation are estimated based on climate (i.e. temperature) and soil moisture conditions. Land management practices interact with hydrology, erosion and vegetation growth via their influence on vegetation cover, biomass and soil moisture condition. The model has been demonstrated to be robust for blanket peat erosion modelling with riverine sediment flux data in the UK. In this paper, the PESERA-PEAT model is applied to investigate the impact of environmental change on the blanket peat erosion at a global scale. Climatic scenarios to the end of 21st Century were derived, as part of the QUEST-GSI initiative, from the outputs of seven global climate models: CGCM3 and CCCMA (Canada); CSIRO Mark III (Australia); IPSL (France); ECHAM5 (Germany); CCSM (US National Centre for Atmospheric Research (NCAR)); HadCM3 and HadGEM1 (UK). Land management practice such as artificial drainage is considered to examine if it is possible to buffer the impact of climate change on erosion through managing blanket peatlands in

  16. Peat conditions mapping using MODIS time series

    NASA Astrophysics Data System (ADS)

    Poggio, Laura; Gimona, Alessandro; Bruneau, Patricia; Johnson, Sally; McBride, Andrew; Artz, Rebekka

    2016-04-01

    Large areas of Scotland are covered in peatlands, providing an important sink of carbon in their near natural state but act as a potential source of gaseous and dissolved carbon emission if not in good conditions. Data on the condition of most peatlands in Scotland are, however, scarce and largely confined to sites under nature protection designations, often biased towards sites in better condition. The best information available at present is derived from labour intensive field-based monitoring of relatively few designated sites (Common Standard Monitoring Dataset). In order to provide a national dataset of peat conditions, the available point information from the CSM data was modelled with morphological features and information derived from MODIS sensor. In particular we used time series of indices describing vegetation greenness (Enhanced Vegetation Index), water availability (Normalised Water Difference index), Land Surface Temperature and vegetation productivity (Gross Primary productivity). A scorpan-kriging approach was used, in particular using Generalised Additive Models for the description of the trend. The model provided the probability of a site to be in favourable conditions and the uncertainty of the predictions was taken into account. The internal validation (leave-one-out) provided a mis-classification error of around 0.25. The derived dataset was then used, among others, in the decision making process for the selection of sites for restoration.

  17. Understanding Peat Bubbles: Biogeochemical-Hydrological Linkages

    NASA Astrophysics Data System (ADS)

    Strack, M.

    2009-05-01

    Decomposition of organic matter in peatland ecosystems produces gaseous end-products that can accumulate at depth and result in the build up of free-phase gas below the water table. This free-phase gas, or bubbles, reduces hydraulic conductivity, alters hydrologic and chemical gradients, and affects productivity surface vegetation through its role in peat buoyancy. In terms of greenhouse gas dynamics, these bubbles are likely the dominant subsurface stock of methane (CH4) and release of this CH4 to the atmosphere via ebullition may account for a significant portion of total efflux. Despite the importance of entrapped bubbles for peatland ecohydrological function there is still little known about how the quantity of bubbles varies between peatland types and at smaller scales within a peatland. Profiles of bubbles collected from several locations within four peatlands reveal that bubble volume varies significant among peatlands, between microforms and with depth. Previous studies also suggest that ebullition is spatially and temporally variable. This spatial variability may have important impacts on system ecohydrology and should be incorporated in models of peatland hydrology and development. This requires the difficult task of mapping bubble volume in three dimensions and over large areas. The potential for geophysical methods and the use of surface features to address this task will be discussed.

  18. RETENTION TIME EFFECT ON METAL REMOVAL BY PEAT COLUMNS

    SciTech Connect

    Nelson, E

    2007-02-28

    The potential use of a peat bed to treat the H-12 Outfall discharge to bring it to new compliance limits was previously investigated and reported utilizing a 7 hour retention time. The influence of retention time (contact time) of water with peat moss on the removal of copper from the water was investigated under laboratory conditions using vertical flow peat moss columns. Reduction of the necessary retention time has a large influence on the design sizing of any peat bed that would be constructed to treat the H-12 discharge on a full scale basis. Retention times of 5 hours, 3 hours and 1 hour were tested to determine the copper removal by the peat columns using vertical flow. Water samples were collected after 4, 8, 12, and 16 water volumes had passed through the columns and analyzed for a suite of metals, with quantitative emphasis on copper. Laboratory results indicated that copper removal was very high at each of the 3 retention times tested, ranging from 99.6 % removal at 5 and 3 hours to 98.8% removal at 1 hour. All these values are much lower that the new compliance limit for the outfall. The results also indicated that most divalent metals were removed to their normal reporting detection limit for the analytical methods used, including zinc. Lead levels in the H-12 discharge used in this study were below PQL in all samples analyzed. While each of the retention times studied removed copper very well, there were indications that 1 hour is probably too short for an operational, long-term facility. At that retention time, there was about 6% compaction of the peat in the column due to the water velocity, and this may affect long term hydraulic conductivity of the peat bed. At that retention time, copper concentration in the effluent was higher than the other times tested, although still very low. Because of the potential compacting and somewhat reduced removal efficiency at a 1 hour retention time, it would be prudent to design to at least a 3 hour retention

  19. Interference of L-α-aminoocy-β-phenylpropionic acid with cold-induced sphagnorubin synthesis in Sphagnum magellanicum BRID.

    PubMed

    Tutschek, R

    1982-08-01

    The ability of the phenylalanine ammonia-lyase (PAL)-inhibitor L-α-aminooxy-β-phenyl-propionic acid (AOPP) to suppress the synthesis of the main reddish-violet wall pigment of Sphagnum magellanicum (sphagnorubin) was investigated. Fifty percent inhibition is achieved with 14 μM AOPP in mosses stimulated to intensive coloring by sugar feeding. AOPP does not affect the content of free amino acids, except for phenylalanine, during cold-induced sphagnorubin synthesis. AOPP dramatically amplifies the increase in extractable PAL activity in response to cold treatment. Phenylalanine applied in vivo causes an eminent increase in PAL activity, above the level of the cold-treated mosses. The results from the feeding experiments are discussed in connection with a possible end-product repression in PAL activity with sphagnorubin-synthesizing mosses. These results are correspond best to the theory that the enzyme level is regulated independently from a mechanism of feedback repression. PMID:24271864

  20. Active Sphagnum girgensohnii Russow Moss Biomonitoring of an Industrial Site in Romania: Temporal Variation in the Elemental Content.

    PubMed

    Culicov, Otilia A; Zinicovscaia, Inga; Duliu, O G

    2016-05-01

    The moss-bag transplant technique was used to investigate the kinetics of the accumulation of 38 elements in Sphagnum girgensohni moss samples in the highly polluted municipality of Baia Mare, Romania. The moss samples collected from the unpolluted Vitosha Mountain Natural Reserve, Bulgaria, were analyzed after 1, 2, 3, and 4 months of exposure, respectively. The ANOVA method was used to assay the statistical significance of the observed changes in elemental content, as determined by neutron activation analysis. The content of Zn, Se, As, Ag, Cd, and Sb increased steadily, while that of physiologically active K and Cl, as well as Rb and Cs, decreased exponentially. The study showed that an adequate application of the moss transplant technique in an urban environment should consider the exposure time as a critical parameter, since particular elements are depleted in the moss at sites with high atmospheric loading of metals. PMID:27003805

  1. Models of the geomorphology, hydrology, and development of domed peat bodies

    SciTech Connect

    Winston, R.B.

    1994-12-01

    Because peat accumulates only beneath the water table, the shape of a peat body should reflect the shape of its water table and thus the hydrology of the peat body. Three different models successfully reproduce the observed peat dome morphology, including a central bog plain. In the first model, the bog plain develops because peat accumulation is limited by anaerobic decay of peat beneath the water table. With certain simplifying assumptions, an analytic solution for this model can be obtained. The other two models are more easily investigated numerically. In the first model, the initial peat accumulation rate is limited only by plant growth and decay and is the maximum rate observed during peat dome development. As a peat dome expands laterally, peat accumulation slows because the water table ceases to rise fast enough to preserve all the available plant material. Eventually, anaerobic decay beneath the water table matches the rate of peat addition to the top of the peat body, and net peat accumulation ceases. 17 refs., 2 tabs.

  2. Community heterogeneity of Early Pennsylvanian peat mires

    USGS Publications Warehouse

    Gastaldo, R.A.; Stevanovic-Walls, I. M.; Ware, W.N.; Greb, S.F.

    2004-01-01

    Reconstructions of Pennsylvanian coal swamps are some of the most common images of late Paleozoic terrestrial ecosystems. All reconstructions to date are based on data from either time-averaged permineralized peats or single-site collections. An erect, in situ Early Pennsylvanian forest preserved above the Blue Creek Coal, Black Warrior Basin, Alabama, was sampled in 17 localities over an area of >0.5 km2, resulting in the first temporally and spatially constrained Pennsylvanian mire data set. This three-tiered forest was heterogeneous. Lycopsid and calamitean trees composed the canopy, and lepidodendrids, Lepidophloios, and sigillarians grew together at most sites. More juvenile than mature lycopsid biomass occurs in the forest-floor litter, indicating a mixed-age, multicohort canopy. Pteridophytes (tree fern) and pteridosperms (seed fern) dominated as understory shrubs, whereas sphenophyllaleans, pteridophytes, and pteridosperms composed the ground-cover and liana tier. The proportion of canopy, understory, and ground-cover biomass varied across the forest. Low proportions of ground-cover and liana taxa existed where canopy fossils accounted for >60% of the litter. There is a distinct spatial clustering of sites with more or less understory (or ground cover) where canopy contribution was <60%. Where canopy biomass was low (<50%), understory shrubs contributed more biomass, indicative of light interception and/or competition strategies. Sphenopteris pottsvillea, a ubiquitous ground-cover plant, is abundant in all sites except one, where pteridosperm creepers and lianas dominate the litter, interpreted to indicate total suppression of other ground-cover growth. Ecological wet-dry gradients identified in other Pennsylvanian swamps do not exist in the Blue Creek mire, with the interpreted wettest (Lepidophloios), driest (Sigillaria), and intermediate (Lepidodendron sensu latu) taxa coexisting in most assemblages. ?? 2004 Geological Society of America.

  3. Peat resources of North Carolina. Quarterly progress report

    SciTech Connect

    Ingram, R.L.; Otte, L.J.

    1980-07-01

    Although the work on North Carolina peat deposits is far from complete, a preliminary estimate of the amount of peak was made. Table 1 has the listing of all three types of deposits, Pocosin, River Flood Plain and Carolina Bays, and their description such as area, weight, thickness and quality estimation. Work on the peats of Light Ground Pocosin has been completed and the final report will be distributed soon. Work is continuing on the three largest Pocosin deposits; East Dismal Swamp (Dare Peninsula), Dismal Swamp, and Croatan Forest. As for river deposits, reconnaissance work indicates that peat is to be found along the lower floodplains of the Chowan, Roanoke, and Cape Fear Rivers. The quality (ash content) is much more variable than for the pososin peats. There are approximately 2100 Carolina Bays deposits, over 800 ft long. A map is provided showing their distribution. Preliminary work shows that most of these bays contain good peat up to a maximum thickness of 15 ft.

  4. Afobazole protects rats exposed to peat smoke in utero.

    PubMed

    Gorbatova, D M; Litvinova, S A; Durnev, A D; Seredenin, S B

    2015-03-01

    Female outbred albino rats were daily subjected to forced inhalations of peat smoke (4 cores packed with a mixture of peat (70%) and wood pulp (30%); 0.46 g, pH at least 5.5, core burning time 6 min,; total exposure 44 min) per se and in combination with oral afobazole (anxiolytic) in doses of 1 and 10 mg/kg on days 1-20 of pregnancy. Some groups of females received oral afobazole (200 mg/kg) after delivery, due to which their newborn rats received the drug in doses of 1-10 mg/kg with maternal milk on days 1-20 of life. Exposure to peat smoke inhibited body weight gain in the progeny on days 5-60 of life. Afobazole treatment during the pre- and postnatal periods prevented this effect. Open field testing showed that exposure to peat smoke prolonged the motor activity in the progeny and impaired the loss of orientation and exploratory behavior during repeated testing. Oral afobazole (1 and 10 mg/kg) during the prenatal and/or postnatal period (with maternal milk) prevented the effects of peat smoke. PMID:25778655

  5. Analyzing peat pyrolysis by in-situ FTIR

    SciTech Connect

    Fen, J.; Li, W.Y.; Li, F.; Xie, K.C.

    1997-12-31

    Coal pyrolysis is complex process that includes many small reactions. Being complicated, it is difficult to study the pyrolysis mechanism with high rank coal directly. Peat is a rudimentary coal which has the most simple structure with lower polymerization. Some researchers think that the key to understanding coal structure is in an appreciation of the molecular components of the original peat swamp and how these might be modified. It is generally agreed that the chemical diversity of various coals will affect rate of coal combustion through the devolatilization process. Upon heating, some of the chemical bonds in coal undergo cracking and result in the release of light gases and the production of tar. Through analysis of peat which is best model compound of coal, some basic step reactions of coal can be understood. The objective of this study is to analyze peat pyrolysis using a in-situ pyrolysis-FTIR and to establish the pyrolysis model. The results show that during rapid peat pyrolysis, all the functional groups produced have almost the same activity energy; the difference among them is the degree of reaction.

  6. Magnitude and timing of peat-to-coal compaction

    SciTech Connect

    Nadon, G.C.

    1998-08-01

    The peat-to-coal transition is commonly assumed to be accompanied by compaction that decreases the thickness of the organic deposit to values of 10% or less of the original peat thickness. Decompaction modeling using such values for coal seams in contact with penecontemporaneous channel sandstones leads to impossible depositional geometries for the sandstones, which have a final thickness that is 90% of their original thickness. Similarly, decompaction modeling of the fragments of organic material within channel lags using the assumed large peat compaction value results in the destruction of the associated sedimentary structures, such as trough cross-beds. Dinosaur tracks in the roofs of coal mines show a shallow depth of penetration and a preservation of foot morphology that is not possible unless the peat the animals walked upon was very firm. These data confirm the macroscopic observations from coal balls that the compaction associated with the peat-to-coal transformation is minimal. Equally important, the data also show that most of the compaction occurs essentially at the surface and not at the depths where coalification takes place.

  7. Reducing the carbon footprint of Canadian peat extraction and restoration.

    PubMed

    Waddington, James M; Plach, Janina; Cagampan, Jason P; Lucchese, Maria; Strack, Maria

    2009-06-01

    The Canadian horticultural peat industry generates carbon emissions through various methods of peat extraction, processing, and land-use changes. This study provides a carbon emissions analysis comparing the traditional vacuum harvest (VH) and block-cut (BC) extraction techniques to a new acrotelm transplant (AT) method that restores natural peatland function by preserving and replacing the surface layer vegetation as part of the extraction process. The relative global warming potential for each extraction method was determined by estimating carbon dioxide (CO2) and methane exchange for each phase of peat extraction, including emissions from land-use change and machinery fuel consumption. Preliminary findings, based on 1 y of measurements, indicate that the AT technique has the lowest annual carbon emissions compared to the VH and BC methods. Projected total carbon emissions from a 75-ha peatland after 50 y of extraction using the AT technique produced a sink of approximately 3300 t CO2 equivalents (CO2-e). This represents a marked reduction in total carbon emissions estimated for the VH (19 000 t CO2-e) and BC (29 000 t CO2-e) extraction techniques. This analysis suggests that the AT method reestablishes peat accumulation and peatland carbon storage function more effectively than the VH and BC methods, which are associated with delayed restoration efforts. Consequently, the AT technique has the potential to greatly reduce the carbon footprint of the Canadian horticultural peat industry. PMID:19739553

  8. Gas bubble transport and emissions for shallow peat from a northern peatland: The role of pressure changes and peat structure

    NASA Astrophysics Data System (ADS)

    Chen, Xi; Slater, Lee

    2015-01-01

    Gas bubbles are an important pathway for methane release from peatlands. The mechanisms controlling gas bubble transport and emissions in peat remain uncertain. The effects of hydrostatic pressure and peat structure on the dynamics of gas bubbles in shallow peat were therefore tested in laboratory experiments. A peat monolith was retrieved from a raised bog and maintained in a saturated state. Three distinct layers were identified from noninvasive permittivity measurements supported by soil physical properties (porosity, bulk density). Phase I of the experiment involved monitoring for the accumulation of gas bubbles under steady pressure and temperature conditions. The data showed evidence for gas bubbles being impeded by a shallow semiconfining layer at depths between 10 and 15 cm. Visible gas bubbles observed on the side of the sample box were recorded over time to estimate changes in the vertical distribution of volumetric gas content. Porosity estimates derived using the Complex Refraction Index Model (CRIM) suggest that gas bubbles enlarge the pore space when the exerted pressure is high enough. Phase II involved triggering release of trapped bubbles by repeatedly increasing and decreasing hydrostatic pressure in an oversaturated condition. Comparison of changes in pressure head and methane density in the head space confirmed that the increasing buoyancy force during drops in pressure is more important for triggering ebullition than increasing mobility during increases in pressure. Our findings demonstrate the importance of changes in hydrostatic pressure on bubble size and variations in resistance of the peat fabric in regulating methane releases from peatlands.

  9. Processes in the pore waters of peat deposits

    SciTech Connect

    Levshenko, T.V.; Efremova, A.G.; Galkina, Z.M.; Surkova, T.E.; Tolstov, K.A.

    1983-01-01

    The composition of the waters of modern peat bogs that have developed in the intracontinental regions under the conditions of bogs of the high-moor, mixed, and lowmoor types have been investigated for the case of a number of peat deposits of the Smolensk, Volgorad, and Pskov provinces. During the work the pH of the deposits and the C1-, Alk, SO/sup 2/-, Ca/sup 2 +/, Mg/sup 2 +/, K- contents of the pore water of modern peat beds were studied. The thickness of the deposits studied amounted to 5-7 m. Samples were taken every 0.5 m in depth. The water was separated from the deposits by pressing out.

  10. 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.

  11. Dynamic Characteristics of Penor Peat Using MASW Method

    NASA Astrophysics Data System (ADS)

    Zainorabidin, A.; Said, M. J. M.

    2016-07-01

    The dynamic behaviour of soil affected the mechanical properties of soil such as shear wave velocity, shear modulus, damping ratio and poisson's ratio [1] which is becoming important aspect need to be considered for structures influences by dynamic movement. This study is to determine the dynamic behaviour of Penor peat such as shear wave velocity using MASW and estimation its shear modulus. Peat soils are very problematic soils since it's have high compressibility, low shear strength, high moisture content and low bearing capacity which is very not suitable materials to construct any foundation structures. Shear wave velocity ranges between 32.94 - 95.89 m/s and shear modulus are ranging between 0.93 - 8.01 MPa. The differences of both dynamic properties are due to the changes of peat density and affected by the fibre content, organic content, degree of degradation and moisture content.

  12. Hydrological controls on rate of organic matter mineralization in peats

    NASA Astrophysics Data System (ADS)

    Ghezzehei, Teamrat; Arnold, Chelsea; Asefaw Berhe, Asmeret

    2016-04-01

    The predominant factor that ties together the formation and persistence of peat soils across regions is their dependence on localized hydrology. Hydrology also plays a dominant role in the relative strength of peatlands as sinks for atmospheric carbon dioxide and sources of methane, and thus on peatland net climate impact. Drying of peat soils by climate change and/or drainage is typically followed by reduction in methane emissions. However, this may easily be offset by the increase in carbon dioxide production. Therefore, mechanistic understanding of peatland hydrology and its association with carbon cycling is a prerequisite for assessing vulnerability of peats to disturbances and for incorporating the associated feedbacks in carbon-climate models. We will present physically based model that ties together the structure of peat soils (mainly pore size distribution and mechanical stability) to rates of aerobic and anaerobic decomposition over a wide range of soil water potentials. Peats consist of hierarchical structure with clear separation of the pores into a population of micropores within clumps of organic matter and/or soil aggregates and a group of macropores between clumps and/or aggregates. This essentially partitions the carbon stock in peat soils in to multiple pools that become mineralizable at disparate water potential ranges. While the carbon in macropores can readily be decomposed by aerobic microorganisms when the soil is only slightly drained, the carbon in fine pores remains largely protected from aerobic microbes until the water potential exceeds a threshold that lets in oxygen. In this presentation we will show the mathematical development of the model and illustrative examples that compare projections with data derived from the literature.

  13. State of New York peat resource inventory. Volume 1

    SciTech Connect

    Mankinen, G.W.; Korpijaakko, E.; Shneyer, W.A.

    1982-07-01

    A comprehensive peat resource inventory of the State of New York has been prepared based on airphoto interpretation supported by field reconnaissance and detailed surveys of certain selected peatlands. The entire State, with the exception of Adirondack Park and a number of other protected areas, was included in the study. A total of 872 peatlands were identified, of which 235 individual deposits were judged usable for peak ;mining and were mapped using airphotos. Of these, approximately 5740 acres were selected for detailed surveys. Over 425 boreholes were made on these and other individual deposits across the State and 138 samples were taken for laboratory analysis. The results of the inventory have been recorded as a set of index maps at a scale of 1:250,000 showing the location of all the mapped and catalogued deposits. Also, maps at a scale of 1:24,000 outlining all the mapped deposits were prepared as well as at a scale of 1:10,000 for the deposits studied in detail. The study shows that the State of New York has over 145,910 acres of peatland containing an estimated 336 million tons of peat (at a 50% moisture content) located in deposits which may be technically mineable. However, various other factors, such as ownership, location in a park, wildlife management holdings and an existing use may exclude some of the otherwise potential deposits from possible use. The peat deposits of New York State generally contain high fuel grade peat. Laboratory analysis of over 100 samples taken from representative bogs revealed the average calorific value of New York peat to be 8860 Btu/lb (on a dry basis) and the ash content to be 13.1%. This compares favorably with the quality of fuel peats used in Europe.

  14. Application of microwave digestion to the analysis of peat

    USGS Publications Warehouse

    Papp, C.S.E.; Fischer, L.B.

    1987-01-01

    A microwave digestion technique for the dissolution of peat is described and compared with a dry ashing method and a nitric - perchloric - hydrofluoric acid wet digestion. Peat samples with different organic matter contents were used and Ca, Mg, Fe, AI, Na, K, Mn, Zn, Cu and Li were determined by atomic absoprtion spectrometry. The results obtained using the three dissolution techniques were in good agreement. The microwave method has the advantage of digesting the samples in less than 2 h and uses less acid than the conventional wet digestion method. Keeping the volume of the acid mixture as small as possible minimises contamination and leads to lower blank values.

  15. Change in the chemical composition of humic acids in peat thermolysis

    SciTech Connect

    Tarnovskaya, L.I.; Maslov, S.G.

    1994-12-31

    The preliminary heat treatment of peat to 250 degrees centigrade may be a very effective factor in regulating the selectivity of a number of processes of complex peat processing schemes. Thermolysis of humic acids (in peat) was performed and solid residues were studied.

  16. Genesis of peat-bog soils in the northern taiga spruce forests of the Kola Peninsula

    SciTech Connect

    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).

  17. Nutrient load can lead to enhanced CH4 fluxes through changes in vegetation, peat surface elevation and water table depth in ombrotrophic bog

    NASA Astrophysics Data System (ADS)

    Juutinen, Sari; Bubier, Jill; Larmola, Tuula; Humphreys, Elyn; Arnkil, Sini; Roy, Cameron; Moore, Tim

    2016-04-01

    Atmospheric nitrogen (N) deposition has led to nutrient enrichment in wetlands, particularly in temperate areas, affecting plant community composition, carbon (C) cycling, and microbial dynamics. It is vital to understand the temporal scales and mechanisms of the changes, because peatlands are long-term sinks of C, but sources of methane (CH4), an important greenhouse gas. Rainwater fed (ombrotrophic) bogs are considered to be vulnerable to nutrient loading due to their natural nutrient poor status. We fertilized Mer Bleue Bog, a Sphagnum moss and evergreen shrub-dominated ombrotrophic bog near Ottawa, Ontario, now for 11-16 years with N (NO3 NH4) at 0.6, 3.2, and 6.4 g N m-2 y-1 (~5, 10 and 20 times ambient N deposition during summer months) with and without phosphorus (P) and potassium (K). Treatments were applied to triplicate plots (3 x 3 m) from May - August 2000-2015 and control plots received distilled water. We measured CH4 fluxes with static chambers weekly from May to September 2015 and peat samples were incubated in laboratory to measure CH4 production and consumption potentials. Methane fluxes at the site were generally low, but after 16 years, mean CH4 emissions have increased and more than doubled in high nitrogen addition treatments if P and K input was also increased (3.2 and 6.4 g N m-2yr-1 with PK), owing to drastic changes in vegetation and soil moisture. Vegetation changes include a loss of Sphagnum moss and introduction of new species, typical to minerogenic mires, which together with increased decomposition have led to decreased surface elevation and to higher water table level relative to the surface. The trajectories indicate that the N only treatments may result in similar responses, but only over longer time scales. Elevated atmospheric deposition of nutrients to peatlands may increase loss of C not only due to changes in CO2 exchange but also due to enhanced CH4 emissions in peatlands through a complex suite of feedbacks and interactions

  18. INFLUENCE OF PEAT ON FENTON OXIDATION: JOURNAL ARTICLE

    EPA Science Inventory

    NRMRL-ADA-99303 Huling*, S.G., Arnold, R.G., Sierka, R.A., and Miller, M.R. Influence of Peat on Fenton Oxidation. Published in: Water Research 35 (7):1687-1694 (2001). A diagnostic probe was used to estimate the activity of Fenton-deriv...

  19. Organic matter in a coal ball: Peat or coal?

    USGS Publications Warehouse

    Hatcher, P.G.; Lyons, P.C.; Thompson, C.L.; Brown, F.W.; Maciel, G.E.

    1982-01-01

    Chemical analyses of morphologically preserved organic matter in a Carboniferous coal ball reveal that the material is coalified to a rank approximately equal to that of the surrounding coal. Hence, the plant tissues in the coal ball were chemically altered by coalification processes and were not preserved as peat. Copyright ?? 1982 AAAS.

  20. 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.

  1. 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.

  2. 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...

  3. Stable Isotope Probing of Peat and Forest Floor Amendments

    NASA Astrophysics Data System (ADS)

    Quideau, Sylvie; Béasse, Mark

    2013-04-01

    In Alberta, Canada, land reclamation efforts utilize peat as an organic amendment to help reclaim decommissioned oil sands mine sites to upland boreal forests. This study investigates the rhizosphere microbial communities of two pioneer species, aspen (Populus tremuloides Michx.), a species not known for strong associations with the soil microbial community, and alder (Alnus crispa Ait.), a species well known for mutualism with actinomycetes. Specifically, the objective was to determine how different organic amendments (peat versus forest floor) influenced the rhizosphere microbial communities and how this could be linked to plant growth. Seedlings were grown for 20 weeks in forest floor material, peat, and a combination of both. They were pulse labelled with 13CO2 (g) and subsequently harvested for plant growth measurements. While analysis of plant growth attributes did not indicate any effect of the organic amendment on aspen growth, alder reported significantly less growth in peat treatments. The rhizosphere soils were extracted for compound-specific analysis of δ13C in microbial phospholipid fatty acids. Stable isotope probing showed greater carbon flow between trees and their rhizosphere communities when seedlings were grown in forest floor material.

  4. The effects of salinization on aerobic and anaerobic decomposition and mineralization in peat meadows: the roles of peat type and land use.

    PubMed

    Brouns, Karlijn; Verhoeven, Jos T A; Hefting, Mariet M

    2014-10-01

    Peat soils comprise a large part of the western and northern Netherlands. Drainage for agriculture has caused increased soil aeration which has stimulated decomposition and, hence, soil subsidence, currently amounting to 1-2 cm/yr. River water is supplied to these peat areas in summer to prevent drying out of the peat soils. Saltwater intrusion and evaporation make this surface water slightly brackish during drought periods. In addition, brackish seepage can surface more easily during such dry periods. We performed an incubation experiment in which the effects of salinization on aerobic decomposition and mineralization of shallow peat samples and anaerobic decomposition and mineralization of deep peat samples were studied. We considered four different types of peat samples: peat sampled in agricultural peat meadows and in nature reserves, originally formed under either eutrophic or oligotrophic conditions. The aerobic decomposition was approximately reduced by 50% after salinization, whereas the anaerobic decomposition rates remained unchanged. Remarkably, the response to salinization did not differ between the peat types and land uses. Ammonium concentrations increased while nitrate concentrations decreased after salinization, probably as a result of reduced nitrification. Especially in the oligotrophic peat, ammonium concentrations increased substantially. Phosphate concentrations increased, possibly caused by changes in desorption and adsorption processes due to higher ion concentrations. DOC concentrations decreased in the brackish samples due to precipitation. Furthermore, the eutrophic peat samples showed increasing sulfate concentrations, both in oxic and anoxic incubations, which was attributed to pyrite oxidation. Independently of salinization, nitrification rates were higher in the agricultural, fertilized, peat soils. In conclusion, while salinization might reduce subsidence rates, it will have adverse effects on water quality. PMID:24837279

  5. Peat bogs offer a reliable, local source of fuel in several states

    SciTech Connect

    Punwani, D.V.

    1981-10-01

    With total estimated US peat resources equivalent to the energy content of 240-billion bbl of oil, peat could be a significant energy resource even if only a fraction of it can be recovered. Resource estimates include only those areas (mostly in eight states) with at least 80 acres/sq mi of peat, where the deposits are at least 4 ft deep. Peat fuel properties, new equipment for peat harvesting and dewatering, and modern combustion technology are described. Conversion to synthetic fuels looks promising.

  6. Fluvial entrainment of low density peat blocks (block carbon)

    NASA Astrophysics Data System (ADS)

    Warburton, Jeff

    2014-05-01

    In many fluvial environments low density materials are transported in significant quantities and these form an important part of the stream load and /or have a distinct impact on sedimentation in these environments. However, there are significant gaps in understanding of how these materials are entrained and transported by streams and rivers. Eroding upland peatland environments in particular, frequently have fluvial systems in which large eroded peat blocks, often exceeding 1 m in length; form an important component of the stream material flux. Transport of this material is significant in determining rates of erosion but also has important impacts in terms of damage to infrastructure and carbon loss. This paper describes a field experiment designed to establish for the first time the conditions under which large peat blocks (c. > 0.1 m b axis) are initially entrained from a rough gravel bed. The field site is Trout Beck, in the North Pennines, Northern England which is an upland wandering river channel with occasional lateral and mid channel bars. Mean low flow stage is typically 0.2 m but during flood can rapidly rise, in one to two hours, to over 1.5 m. To study peat block entrainment a bespoke data acquisition system consisting of two pressure transducers, four release triggers and time lapse camera was set up. The pressure transducers provided a record of local depth and the release triggers were embedded in peat blocks to record initial motion and arranged on the rough stream bed. The time lapse camera provided verification of timing of block entrainment (during daylight hours) and also provided information on the mechanism of initial movement. Peat blocks were cut from a local source and were equidimensional, ranging in size from 0.1 to 0.7 m. The derived entrainment function is related to a critical depth of entrainment. Results demonstrate that peat blocks are entrained when the local depth approximates the height of the peat block. Blocks frequently shift

  7. Untangling climatic and autogenic signals in peat records

    NASA Astrophysics Data System (ADS)

    Morris, Paul J.; Baird, Andrew J.; Young, Dylan M.; Swindles, Graeme T.

    2016-04-01

    Raised bogs contain potentially valuable information about Holocene climate change. However, autogenic processes may disconnect peatland hydrological behaviour from climate, and overwrite and degrade climatic signals in peat records. How can genuine climate signals be separated from autogenic changes? What level of detail of climatic information should we expect to be able to recover from peat-based reconstructions? We used an updated version of the DigiBog model to simulate peatland development and response to reconstructed Holocene rainfall and temperature reconstructions. The model represents key processes that are influential in peatland development and climate signal preservation, and includes a network of feedbacks between peat accumulation, decomposition, hydraulic structure and hydrological processes. It also incorporates the effects of temperature upon evapotranspiration, plant (litter) productivity and peat decomposition. Negative feedbacks in the model cause simulated water-table depths and peat humification records to exhibit homeostatic recovery from prescribed changes in rainfall, chiefly through changes in drainage. However, the simulated bogs show less resilience to changes in temperature, which cause lasting alterations to peatland structure and function and may therefore be more readily detectable in peat records. The network of feedbacks represented in DigiBog also provide both high- and low-pass filters for climatic information, meaning that the fidelity with which climate signals are preserved in simulated peatlands is determined by both the magnitude and the rate of climate change. Large-magnitude climatic events of an intermediate frequency (i.e., multi-decadal to centennial) are best preserved in the simulated bogs. We found that simulated humification records are further degraded by a phenomenon known as secondary decomposition. Decomposition signals are consistently offset from the climatic events that generate them, and decomposition

  8. Critical comparison of peat decomposition proxies and their relationship to peat geochemistry

    NASA Astrophysics Data System (ADS)

    Bindler, Richard; Hansson, Sohia

    2013-04-01

    Mires are known to play a major role in global carbon cycling, and there is an important link between the carbon mass balance of mires and climate. Aspects of this coupling are preserved in the peat that accumulates in mires, and in particular the record of decomposition of organic matter is used as an important proxy for reconstructing this climate-carbon coupling. The geochemical record of major and trace elements in peat is also used as a proxy for other environmental forcings, especially natural and anthropogenic atmospheric inputs on mires, such as soil dust and lead pollution, respectively. However, the geochemical composition of the peat can be influenced by changes in the decomposition of organic matter, which can potentially alter the retention and mobility of trace elements of interest, such as mercury. To understand past climate-carbon interactions and decomposition effects on geochemistry requires quantitative assessments of decomposition. There is, however, no single measurement for decomposition, but rather a range of qualitative proxies is used to estimate mass loss and decomposition. The most common techniques include CN ratios, bulk density and light transmission following an alkaline extract. In this presentation we compare these three proxies in cores from two sites: an oligotrophic mire where we took a core transect from (≤270 cm deep, ca 2400 yr), and an ombrotrophic bog where collected triplicate surface hummock cores (75 cm, ca 500 yr). In the long mire profiles, the three parameters show quite similar large-scale patterns over the length of each profile. It is clear that all three proxies co-vary and the correlations between the proxies are all highly significant (p<0.01). We can reasonably conclude that the three parameters reflect the same long-term qualitative changes in humification, but quantitatively the details among the proxies vary, which alter interpretations of past decomposition changes at centennial resolution. Changes in

  9. Deccesion of peat-moorsh soils under different land use

    NASA Astrophysics Data System (ADS)

    Lipka, K.; Zając, E.

    2009-04-01

    Use of peatlands has a serious impact on soil properties as well as on loss of organic matter. On the basis of survey carried out in 1976, 1993 and 2001 in the Mrowla river valley near Rzeszow, authors analysed changes of the peat-moorsh soils under different land use. The 25- year period was analysed. Survey results comprised: loss of organic matter, advance of moorsh forming process and change of prognostic soil-moisture complexes (after Okruszko). Stratigraphic profiles made in the years1996-2001 were compared and rate of organic mass loss was calculated. The highest values were stated for ploughfields with crop rotation (root plants, industrial plants and cereals). Intensified soil aeration and moorsh forming process as well as wind erosion caused gradual lowering of ground level. Depth of degraded peat layer in roof of surveyed peat deposits was between 0,2 and 0,8 m. Ground surface was lowering of 1,68 cm per year. It was found that, for ploughfields especially, peat-moorhs soil showing medium degree of moorsh forming process (MtII) and prognostic soil-moisture complex BC (periodically drying), after 17 years already, had changed into a soil with high degree of moorsh forming process (MtIII) and prognostic soil-moisture complex C (drying). For meadows and pastures land used such evident change wasn't noticed. During the whole investigation period (25 years) mean lowering of the peat-moorsh soils level along transects lines for different land use was: 1,15 cm per year for meadows and pastures, 1,58 cm pea year for plougfields and 1,38 cm per year for alder wood.

  10. Microbial liquefaction of peat for the production of synthetic fuels

    SciTech Connect

    Gunasekaran, M.

    1988-01-01

    Objectives of this study were: to evaluate the potential of using various microorganisms to hydrolyse and liquify peat; to determine the optimal conditions for peat hydrolysis and liquefaction; to study the co-metabolizable substances; to separate the compounds present in liquified peat by alumina and silica acid chromatography and capillary gas chromatography; and to identify the compounds in liquified peat by capillary GC-Mass spectrometry. Organisms used in the study include: Coprinus comatus, Coriolus hirsutus, Ganoderma lucidum, Lentinus edodes, Lenzites trabea, Phanerochaete chrysosporium, Pleurotus ostreatus, P. sapidus, Polyporus adjustus, Neurospora sitophila, Rhizophus arrhizus, Bacillus subtilis, Acinetobacter sp. and Alcaligenes sp. The fungi were maintained and cultivated in potato dextrose agar at 30 C. The bacteria were maintained in nutrient agar at 30 C. We have also initiated work on coal solubilization in addition to the studies on peat liquefaction. A relatively new substratum or semi-solid base for culture media called Pluronic F-127, or Polyol (BASF, New Jersey). Objectives of this study were: (1) to study the growth patterns of Candida ML 13 on pluronic as substratum; (2) to determine the rate of microbial coal solubilization on pluronic F-127 amended in different growth media; (3) to separate the mycelial mat of Candida ML 13 from unsolubilized coal particles and solubilized coal products from pluronic F-127; (4) to determine the effects of pH on microbial coal solubilization in pluronic F-127 media; (5) the effect of concentration of pluronic F-127 in media on coal solubilization; and, (6) to study the role of extracellular factors secreted by Candida ML 13 on coal solubilization in pluronic F-127 media. Results are discussed. 4 refs.

  11. Advancement of peat hydrogasification. Final report, July 1983

    SciTech Connect

    Garey, M.P.; Rosemary, J.K.

    1983-07-01

    This final technical report summarizes the results of a preliminary conceptual commercial-scale peat hydrogasification plant study performed for the US Department of Energy by the Energy Systems Group of Rockwell International and its subcontractor, the C.E. Lummus Company. The plant design is based on the Rockwell single-stage, entrained flow, short-residence-time hydrogasifier in which peat and hot hydrogen are reacted to produce SNG and a high-value co-product liquid, predominantly chemical-grade benzene. The overall design objective was to integrate the Rockwell hydrogasifier with a combination of unit operations and plant subsystems to yield an effective and economic plant for producing 250 billion Btu per stream day of pipeline quality SNG from peat. The report is divided into two parts. Part I contains a summary of the work performed by Rockwell in support of the Lummus plant design effort. Rockwell provided to Lummus correlations of reactor performance data, cost and design information pertaining to the reactor train, specifications of equipment requirements for the peat drying and pulverization system, and preliminary material balances for an alternate plant design based upon the use of a partial oxidation gasifier system for hydrogen generation. Lummus performed the major part of this study. Their final report to Rockwell is presented in its entirety as Part II of this document. Included are the design and economic bases for the commercial-scale plant concept, detailed descriptions of the selected process configurations, and preliminary order of magnitude estimates for the capital requirements, the net annual operating costs, and an average cost of gas for the proposed plant design. The Lummus section and a review article on peat have been entered separately. (LTN)

  12. 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. PMID:24781330

  13. Dynamics of biogenic gas bubbles in peat: Potential effects on water storage and peat deformation

    NASA Astrophysics Data System (ADS)

    Kellner, E.; Waddington, J. M.; Price, J. S.

    2005-08-01

    Dynamics of biogenic bubbles in peat soils were studied at a field site in southern Québec, Canada. The maximum gas content measured in this study varied spatially with a maximum seasonal increase in volumetric gas content of 0.15. The size of changes in total gas content of a 1 m deep profile was comparable to the seasonal water storage change. Changes in bubble volume in the saturated zone alter the water table level and, consequently, the water content in the unsaturated zone and the apparent water budget. In highly compressible soils (and floating root mats), buoyancy forces from bubbles also cause relations between the surface and the water table to change. These effects cannot be omitted in modeling the hydrology of peatlands. Our results indicate a great spatial variability of trapped bubbles. Using pressure transducers sealed to the surface, we found pressure deviations indicating small areas closed off by bubbles clogging the pores. The hydrological influence of these areas may be considerable as they may restrict or deflect water flows. Open pipe piezometers did not show these pressure deviations, possibly because the closed zones were too small to influence the head in pipes or because of less amount of gas close to the pipe screen.

  14. Regional Haze Evolved from Peat Fires - an Overview

    NASA Astrophysics Data System (ADS)

    Hu, Yuqi; Rein, Guillermo

    2016-04-01

    This work provides an overview of haze episodes, their cause, emissions and health effects found in the scientific literature. Peatlands, the terrestrial ecosystems resulting from the accumulation of partially decayed vegetation, become susceptible to smouldering fires because of natural droughts or anthropogenic-induced drainages. Once ignited, smouldering peat fires persistently consume large amounts of soil carbon in a flameless form. It is estimated that the average annual carbon gas emissions (mainly CO2 and CO) from peat fires are equivalent to 15% of manmade emissions, representing influential perturbation of global carbon circle. In addition to carbon emissions, smouldering peat fires emit substantial quantities of heterogeneous smoke, which is responsible for haze phenomena, has not yet been fully studied. Peat-fire-derived smoke is characterized by high concentration of particulate matter (PM), ranging from nano-scale ultrafine fraction (PM1, particle diameter < 1 μm) to micro-scale fine (PM2.5, particle diameter < 2.5 μm) and coarse fraction (PM10, particle diameter < 10 μm). The dispersal of the smoke could be blocked due to the stagnant weather condition, and then low buoyant smoke plume could accumulate and migrate long distances, leading to regional haze. Apart from air quality deterioration, haze leads to severe reduction in visibility, which strongly affects local transportation, construction, tourism and agriculture-based industries. For example, an unprecedented peatland mega-fire burst on the Indonesian islands Kalimantan and Sumatra during the 1997 El-Niño event, resulting in transboundary smoke-haze disaster. Severe haze events continue to appear in Southeast Asia every few years due to periodical peat fires in this region. In addition, smouldering peat fires have been frequently reported in tropical, temperate and boreal regions (Botswana in 2000, North America in 2004, Scotland in 2006 and Central Russia in 2010 et al.), peat

  15. Microform-related community patterns of methane-cycling microbes in boreal Sphagnum bogs are site specific.

    PubMed

    Juottonen, Heli; Kotiaho, Mirkka; Robinson, Devin; Merilä, Päivi; Fritze, Hannu; Tuittila, Eeva-Stiina

    2015-09-01

    Vegetation and water table are important regulators of methane emission in peatlands. Microform variation encompasses these factors in small-scale topographic gradients of dry hummocks, intermediate lawns and wet hollows. We examined methane production and oxidization among microforms in four boreal bogs that showed more variation of vegetation within a bog with microform than between the bogs. Potential methane production was low and differed among bogs but not consistently with microform. Methane oxidation followed water table position with microform, showing higher rates closer to surface in lawns and hollows than in hummocks. Methanogen community, analysed by mcrA terminal restriction fragment length polymorphism and dominated by Methanoregulaceae or 'Methanoflorentaceae', varied strongly with bog. The extent of microform-related variation of methanogens depended on the bog. Methanotrophs identified as Methylocystis spp. in pmoA denaturing gradient gel electrophoresis similarly showed effect of bog, and microform patterns were stronger within individual bogs. Our results suggest that methane-cycling microbes in boreal Sphagnum bogs with seemingly uniform environmental conditions may show strong site-dependent variation. The bog-intrinsic factor may be related to carbon availability but contrary to expectations appears to be unrelated to current surface vegetation, calling attention to the origin of carbon substrates for microbes in bogs. PMID:26220310

  16. Cultivation and detection of endophytic aerobic methanotrophs isolated from Sphagnum species as a perspective for environmental biotechnology

    PubMed Central

    2014-01-01

    Enriched cultures of microorganisms are an essential step in the production of inoculum of these organisms for biotechnology and bioengineering. The potential application of methanotrophic microorganisms for removal of methane produced from landfills and coal mines as well as biodegradation of toxic compounds has been widely studied. Therefore, searching for new sources of methanotrophs can contribute to increasing the possibilities of biotechnology and bioengineering. Enrichment cultures of endophytic methanotrophs from Sphagnum sp. were initiated in NMS medium, a most widely used medium for cultivation of methanotrophic bacteria from various environments proposed in 1970 by Whittenbury. Incubation was carried out at 10, 20, 30, and 37°C with vigorous shaking on a shaker (180 rpm). The source of carbon and energy for endophytes were methane at the concentration range between 1-20%. It appeared that the consortium of endophytic bacteria grew only at the temperature of 20 and 30°C. During the culture of endophytes, the measurements of gas concentration showed a steady loss of methane and oxygen, as well as accumulation of carbon dioxide as a CH4 oxidation product. The use of FISH has made characterization of endophytic consortia possible. It turned out that the population of endophytes consists of type I and II methanotrophs as well as associated non-methanotrophic bacteria. Furthermore, we determined the potential of the examined bacteria for methane oxidation, which ranged up to 4,7 μMCH4 per ml of the population of endophytes per day. PMID:25401064

  17. Periodicity in growth, productivity, nutrient content and decomposition ofSphagnum recurvum var.mucronatum in a fen woodland.

    PubMed

    Brock, T C; Bregman, R

    1989-03-01

    Condition in the understory of aBetula-carr appeared to be favourable for the growth ofSphagnum recurvum. The estimates of annual productivity and nutrient accumulations forS. recurvum obtained in this wetland forest are in the high range of those reported for peatmosses. On an annual basis, the organic matter production, vegetative reproduction (forking), and accumulation of N, P and K were very much the same for a relatively dry and for a relatively wet year. Periodicity in growth and length increase of the plants, however, differed remarkably between these years, and fruiting was observed in the dry year only.S. recurvum was characterized by a distinct variation in nutrient concentrations both with time and with distance from the capitulum. Organic weight loss during breakdown ofS. recurvum in the wetland forest was low. Release of N, P and particularly K was larger than that of organic matter in decomposingS. recurvum. Nevertheless, a relatively large proportion of the original N and P stock remained associated with the peatmoss material after a 12 month decay period. Observations with the scanning electron microscope revealed that after a year the cells of deadS. recurvum were hardly damaged and only poorly colonized by microorganisms. The characteristics ofS. recurvum described here indicate its potency in directing succession in peatland forests. PMID:23494344

  18. Sources and distribution of trace elements in Estonian peat

    NASA Astrophysics Data System (ADS)

    Orru, Hans; Orru, Mall

    2006-10-01

    This paper presents the results of the distribution of trace elements in Estonian mires. Sixty four mires, representative of the different landscape units, were analyzed for the content of 16 trace elements (Cr, Mn, Ni, Cu, Zn, and Pb using AAS; Cd by GF-AAS; Hg by the cold vapour method; and V, Co, As, Sr, Mo, Th, and U by XRF) as well as other peat characteristics (peat type, degree of humification, pH and ash content). The results of the research show that concentrations of trace elements in peat are generally low: V 3.8 ± 0.6, Cr 3.1 ± 0.2, Mn 35.1 ± 2.7, Co 0.50 ± 0.05, Ni 3.7 ± 0.2, Cu 4.4 ± 0.3, Zn 10.0 ± 0.7, As 2.4 ± 0.3, Sr 21.9 ± 0.9, Mo 1.2 ± 0.2, Cd 0.12 ± 0.01, Hg 0.05 ± 0.01, Pb 3.3 ± 0.2, Th 0.47 ± 0.05, U 1.3 ± 0.2 μg g - 1 and S 0.25 ± 0.02%. Statistical analyses on these large database showed that Co has the highest positive correlations with many elements and ash content. As, Ni, Mo, ash content and pH are also significantly correlated. The lowest abundance of most trace elements was recorded in mires fed only by precipitation (ombrotrophic), and the highest in mires fed by groundwater and springs (minerotrophic), which are situated in the flood plains of river valleys. Concentrations usually differ between the superficial, middle and bottom peat layers, but the significance decreases depending on the type of mire in the following order: transitional mires - raised bogs - fens. Differences among mire types are highest for the superficial but not significant for the basal peat layers. The use of peat with high concentrations of trace elements in agriculture, horticulture, as fuel, for water purification etc., may pose a risk for humans: via the food chain, through inhalation, drinking water etc.

  19. Strong Wavelength Dependence of Aerosol Light Absorption from Peat Combustion

    NASA Astrophysics Data System (ADS)

    Gyawali, M. S.; Chakrabarty, R. K.; Yatavelli, R. L. N.; Chen, L. W. A. A.; Knue, J.; Samburova, V.; Watts, A.; Moosmüller, H.; Arnott, W. P.; Wang, X.; Zielinska, B.; Chow, J. C.; Watson, J. G.; Tsibart, A.

    2014-12-01

    Globally, organic soils and peats may store as much as 600 Gt of terrestrial carbon, representing 20 - 30% of the planet's terrestrial organic carbon mass. This is approximately the same carbon mass as that contained in Earth's atmosphere, despite peatlands occupying only 3% of its surface. Effects of fires in these ecosystems are of global concern due to their potential for enormous carbon release into the atmosphere. The implications for contributions of peat fires to the global carbon cycle and radiative forcing scenarios are significant. Combustion of peat mostly takes place in the low temperature, smoldering phase of a fire. It consumes carbon that may have accumulated over a period of hundreds to thousands of years. In comparison, combustion of aboveground biomass fuels releases carbon that has accumulated much more recently, generally over a period of years or decades. Here, we report our findings on characterization of emissions from laboratory combustion of peat soils from three locations representing the biomes in which these soils occur. Peat samples from Alaska and Florida (USA) and Siberia (Russia) were burned at two different fuel moisture levels. Burns were conducted in an 8-m3 volume combustion chamber located at the Desert Research Institute, Reno, NV, USA. We report significant brown carbon production from combustion of all three peat soils. We used a multispectral (405, 532, 781 nm) photoacoustic instrument equipped with integrating nephelometer to measure the wavelength-dependent aerosol light absorption and scattering. Absorption Ångström exponents (between 405 and 532 nm) as high as ten were observed, revealing strongly enhanced aerosol light absorption in the violet and blue wavelengths. Single scattering albedos (SSA) of 0.94 and 0.99 were observed at 405 and 532 nm, respectively, for the same sample. Variability of these optical parameters will be discussed as a function of fuel and combustion conditions. Other real-time measurements

  20. Atmospheric deposition and isotope biogeochemistry of zinc in ombrotrophic peat

    NASA Astrophysics Data System (ADS)

    Weiss, Dominik J.; Rausch, Nicole; Mason, Thomas F. D.; Coles, Barry J.; Wilkinson, Jamie J.; Ukonmaanaho, Liisa; Arnold, Tim; Nieminen, Tiina M.

    2007-07-01

    Zinc isotope ratios were measured in the top sections of dated ombrotrophic peat cores in Finland to investigate their potential as proxies for atmospheric sources and to constrain post depositional processes affecting the geochemical record. The peat deposits were located in Hietajärvi, a background site well away from any point pollution source and representing 'background' conditions, in Outokumpu, next to a mining site, and in Harjavalta, next to a smelter. Measured total concentrations, calculated excess concentrations and mass balance considerations suggest that zinc is subjected to important biogeochemical cycling within the peat. Significant isotopic variability was found in all three peat bogs, with heavier zinc in the deeper and lighter zinc in the upper sections. Isotope ratios and concentrations correlated in the two peats located next to dominant point sources, i.e. the smelting and mining site, suggesting that zinc isotopes trace pollution sources. Concentration and isotope peaks were offset from the period of mining and smelting activity, supporting migration of zinc down the profile. The δ 66Zn JMC (where δ 66Zn = [( 66Zn/ 64Zn) sample/( 66Zn/ 64Zn) JMC-standard - 1] × 10 3) of the top section sample at the remote Hietajärvi site was 0.9‰ and we suggest this represents the regional background isotope signature of atmospheric zinc. The deeper sections of the peat cores show isotopically heavier zinc than any potential atmospheric source, indicating that post depositional processes affected the isotopic records. The large variations encountered (up to 1.05‰ for δ 66Zn) and Rayleigh modelling imply that multiple fractionation of zinc during diagenetic alterations occurs and nutrient recycling alone cannot explain the fractionation pattern. We propose that zinc isotopes are amenable to identify different atmospheric zinc sources, including zinc derived from anthropogenic activities such as mining and smelting, but multiple biogeochemical

  1. Physical and thermochemical properties of uncontaminated and diesel-contaminated peat

    SciTech Connect

    Ghaly, R.A.; Pyke, J.B.; Ghaly, A.E.; Ugursal, V.I.

    1999-06-01

    Peat, plant matter that is partially fossilized, is formed in poorly oxygenated wetlands where the rate at which the plant matter accumulates is greater than the rate at which it decomposes. Peat is a common solid fuel ranking among coal, coke, wood, and sugarcane bagasse. It has also been used to recover oil during the remediation processes of contaminated water and soil. Because of its high moisture content, peat has a high potential as biofuel material for gasification. However, proper understanding of the physical and thermochemical properties of peat is necessary for the design of thermochemical conversion systems. This study provides information on moisture content, bulk density, particle size, heating values, proximate analysis, ultimate analysis, ash composition, and ash fusibility characteristics of uncontaminated and diesel-contaminated peat. The moisture content of uncontaminated peat was 7.10%, whereas that of diesel-contaminated peat ranged from 8.65% to 10.80%. The bulk density for the uncontaminated peat was 151 kg/m{sup 3}, which increased to 391--534 kg/m{sup 3} due to diesel contamination. Most of the particles (60%) were in the form of dust. The results also showed an ash content of 3.23% and the lower heating value of 17.65 MJ/kg (dry weight basis) for the uncontaminated peat. The ash content decreased substantially, whereas the lower heating value increased due to diesel contamination. The ash fusion temperature of the peat was found to be over 1100 C.

  2. A Digital Soil Mapping approach using neural networks for peat depth mapping in Scotland

    NASA Astrophysics Data System (ADS)

    Aitkenhead, Matt; Saunders, Matt; Yeluripati, Jagadeesh

    2014-05-01

    Spatially explicit and accurate peat depth estimates are required for carbon stock assessment, carbon management stategies , hydrological modelling, ecosystem service assessment and land management (e.g. wind farms). In Scotland, a number of surveys have taken place over the years that have produced data on peat depth, and while many of these surveys have focussed on specific locations or peat bogs, a substantial proportion of the data produced is relatively old and has not been digitised, thus limiting its visibility and utility in new research activities, policy development and land management decision making. Here we describe ongoing work where the key objective is to integrate multiple peat survey datasets with existing spatial datasets of climate, vegetation, topography and geology. The dataset produced is generated from a small number of isolated surveys and while it is not representative of all of Scotland's soils, it is sufficient to demonstrate the conceptual basis for model development. It has been used to develop a neural network model of peat depth that has been applied across Scotland's peat bogs at 100m resolution. The resulting map gives an early indication of the variation of peat depth across the country, and allows us to produce an estimate of mean peat bog depth across the country. This estimate will improve with additional data and will contribute to improving our ability to undertake activities that depend on this kind of information. We have identified data gaps that need to be addressed in order to improve this model, in particular peat depth survey data from a wider range of peat types across the country and in particular, blanket bog and upland peat areas. Ongoing work to identify and integrate additional peat bog depth data is described. We also identify potential uses for the existing maps of peat depth, and areas of future model development.

  3. 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

  4. [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. PMID:22165149

  5. Terpenoid hydrocarbons in Hula peat: Structure and origins

    NASA Astrophysics Data System (ADS)

    Venkatesan, M. I.; Ruth, E.; Kaplan, I. R.

    1986-06-01

    Tri- and tetracyclic diterpenoid and pentacyclic triterpenoid hydrocarbons have been identified in the lipid extracts of three peat samples from the Hula Basin, Israel. Tentative structures for the diterpenoids have been proposed based on mass spectral studies and on extrapolation of known mass spectral fragmentation patterns of most probable biological precursors. The identification of ent-kaurenes in one peat sample appears to be a unique observation. Kaurenes most likely originated from higher plant resins. The triterpenoids in the three samples consist mainly of 17β-hopanes and hopenes, derived from recent biogenic activity. The preponderance of the 17β(H)-hopanes indicates the geological immaturity of the samples and implies that they have undergone only a mild thermal history.

  6. Phenol oxidase activity in secondary transformed peat-moorsh soils

    NASA Astrophysics Data System (ADS)

    Styła, K.; Szajdak, L.

    2009-04-01

    The chemical composition of peat depends on the geobotanical conditions of its formation and on the depth of sampling. The evolution of hydrogenic peat soils is closely related to the genesis of peat and to the changes in water conditions. Due to a number of factors including oscillation of ground water level, different redox potential, changes of aerobic conditions, different plant communities, and root exudes, and products of the degradation of plant remains, peat-moorsh soils may undergo a process of secondary transformation conditions (Sokolowska et al. 2005; Szajdak et al. 2007). Phenol oxidase is one of the few enzymes able to degrade recalcitrant phenolic materials as lignin (Freeman et al. 2004). Phenol oxidase enzymes catalyze polyphenol oxidation in the presence of oxygen (O2) by removing phenolic hydrogen or hydrogenes to from radicals or quinines. These products undergo nucleophilic addition reactions in the presence or absence of free - NH2 group with the eventual production of humic acid-like polymers. The presence of phenol oxidase in soil environments is important in the formation of humic substances a desirable process because the carbon is stored in a stable form (Matocha et al. 2004). The investigations were carried out on the transect of peatland 4.5 km long, located in the Agroecological Landscape Park host D. Chlapowski in Turew (40 km South-West of Poznań, West Polish Lowland). The sites of investigation were located along Wyskoć ditch. The following material was taken from four chosen sites marked as Zbechy, Bridge, Shelterbelt and Hirudo in two layers: cartel (0-50cm) and cattle (50-100cm). The object of this study was to characterize the biochemical properties by the determination of the phenol oxidize activity in two layers of the four different peat-moors soils used as meadow. The phenol oxidase activity was determined spectrophotometrically by measuring quinone formation at λmax=525 nm with catechol as substrate by method of Perucci

  7. 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.

  8. The sorption of Zectran on bottom sediments and peat moss

    SciTech Connect

    Matthews, E.W.; Faust, S.D.

    1981-01-01

    A modified analytical method employed to determine the insecticide Zectran in natural waters frequently has resulted in erroneous data. The errors have been attributed to interferences from particulate matter in these waters. In order to evaluate analytical interferences due to sorption of Zectran on particulates, a series of experiments was performed using bottom sediments and a peat moss in contact with aqueous solutions of zectran at a pH values of 6.0 and 20 degrees C. Isotherm studies confirmed that Zectran sorption occurs in a direct relation to the amount of chemically oxidizable carbon present in the bottom sediments or peat moss. However, the extent of sorption was limited, which suggested that particulates may not be the primary interference in the modified analytical method.

  9. Modelling uncertainty of carbon stocks changes in peats.

    NASA Astrophysics Data System (ADS)

    Poggio, Laura; Gimona, Alessandro; Aalders, Inge; Morrice, Jane; Hough, Rupert

    2015-04-01

    Global warming might change the hydrology of upland blanket peats in Scotland with increased risk of release of the stored carbon. It is therefore important to model the loss of carbon in peat areas with estimation of the damage potential. The presented approach has the potential to provide important information for the assessment of carbon stocks over large areas, but also in case of changes of land use, such as construction of wind farms. The provided spatial uncertainty is important for including the results in further environmental and climate-change models and for decision making in order to provide alternatives and prioritisation. In this study, main peat properties (i.e. depth, water content, bulk density and carbon content) were modelled using a hybrid GAM-geostatistical 3D approach that allows full uncertainty propagation. The approach used involves 1) modelling the trend with full 3D spatial correlation, i.e., exploiting the values of the neighbouring pixels in 3D-space, and 2) 3D kriging as spatial component. The uncertainty of the approach is assessed with iterations in both steps of the process. We studied the difference between local estimates obtained with the present method and local estimates obtained assuming the global average value across the test area for Carbon content and bulk density. To this end, virtual pits with a surface area of 30x30 m were excavated for the whole peat depth at randomly selected locations. Calculated uncertainty was used to estimate credible intervals of C loss. In this case the estimates obtained with the proposed approach are higher that what would be obtained by assuming spatial homogeneity and using just average values across the area. This has implications for environmental decision making and planning as, in this case, it is likely that more carbon would be lost than estimated using traditional approaches.

  10. Old carbon efflux from tropical peat swamp drainage waters

    NASA Astrophysics Data System (ADS)

    Vihermaa, Leena; Waldron, Susan; Evers, Stephanie; Garnett, Mark; Newton, Jason

    2014-05-01

    Tropical peatlands constitute ~12% of the global peatland carbon pool, and of this 10% is in Malaysia1. Due to rising demand for food and biofuels, large areas of peat swamp forest ecosystems have been converted to plantation in Southeast Asia and are being subjected to degradation, drainage and fire, changing their carbon fluxes eg.2,3. Dissolved organic carbon (DOC) lost from disturbed tropical peat can be derived from deep within the peat column and be aged from centuries to millennia4 contributing to aquatic release and cycling of old carbon. Here we present the results of a field campaign to the Raja Musa Peat Swamp Forest Reserve in N. Selangor Malaysia, which has been selectively logged for 80 years before being granted timber reserve status. We measured CO2 and CH4efflux rates from drainage systems with different treatment history, and radiocarbon dated the evasion CO2 and associated [DOC]. We also collected water chemistry and stable isotope data from the sites. During our sampling in the dry season CO2 efflux rates ranged from 0.8 - 13.6 μmol m-2 s-1. Sediments in the channel bottom contained CH4 that appeared to be primarily lost by ebullition, leading to sporadic CH4 efflux. However, dissolved CH4 was also observed in water samples collected from these systems. The CO2 efflux was aged up to 582±37 years BP (0 BP = AD 1950) with the associated DOC aged 495±35 years BP. Both DOC and evasion CO2 were most 14C-enriched (i.e. younger) at the least disturbed site, and implied a substantial component of recently fixed carbon. In contrast, CO2 and DOC from the other sites had older 14C ages, indicating disturbance as the trigger for the loss of old carbon. 1Page et al., 2010 2Hooijer et al., 2010 3Kimberly et al., 2012 4Moore et al., 2013

  11. Alkylation of lignites and peat in low-temperature plasma

    SciTech Connect

    L.I. Shchukin; S.I. Zherebtsov; M.V. Kornievich; O.A. Skutina

    2007-02-15

    The alkylation of lignites and peat was carried out at 50-270{sup o}C in different plasmas. The degree of conversion determined as the yield of the alcohol-benzene extract increases on passing from methane to alcohol plasma. The dependence of the extract yield on the plasma temperature, treatment time, and sample grinding degree was studied. 5 refs., 4 figs., 2 tabs.

  12. Climate variability and long-term expansion of peat lands in Arctic Norway during the late Pliocene (ODP Site 642, Norwegian Sea)

    NASA Astrophysics Data System (ADS)

    Panitz, S.; Salzmann, U.; Risebrobakken, B.; De Schepper, S.; Pound, M. J.

    2015-12-01

    Little is known about the terrestrial response of high latitude Scandinavian vegetation to the warmer-than-present climate of the Late Pliocene (Piacenzian, 3.60-2.58 Ma). In order to assess Piacenzian terrestrial climate variability we present the first high resolution reconstruction of vegetation and climate change in northern Norway between 3.6-3.14 Ma. The reconstructions are derived from pollen assemblages in the marine sediments of ODP Hole 642B, Norwegian Sea (67° N). The palynological assemblages provide a unique record of latitudinal and altitudinal shifting of the forest boundaries, with vegetation alternating between cool temperate forest during warmer-than-present intervals, and boreal forest similar to today during cooler intervals. The northern boundary of the nemoral to boreonemoral forest zone was displaced at least 4-8° further north and warmest month temperatures were 6-14.5 °C higher than present during warm phases. Warm climatic conditions persisted during the earliest Piacenzian (ca. 3.6-3.47 Ma) with diverse cool temperate nemoral to boreonemoral forests growing in the lowlands of the Scandinavian mountains. A distinct cooling event at ca. 3.47 Ma resulted in a southward shift of vegetation boundaries, leading to the predominance of boreal forest and the development of open, low alpine environments. The cooling culminated around 3.3 Ma, coinciding with Marine Oxygen Isotope Stage (MIS) M2. Warmer climate conditions returned after ca. 3.29 Ma with higher climate variability indicated by the repeated expansion of forests and peat lands during warmer and cooler periods, respectively. Climate progressively cooled after 3.18 Ma, resembling climatic conditions during MIS M2. A high variability of Norwegian vegetation and climate changes during the Piacenzian is superimposed on a long-term cooling trend. This cooling was accompanied by an expansion of Sphagnum peat lands that potentially contributed to the decline in atmospheric CO2-concentrations

  13. Hydroclimatic shifts recorded in peat archive from Rąbień mire (Central Poland) - better understanding of past climate changes using multidisciplinary approach

    NASA Astrophysics Data System (ADS)

    Słowiński, Michał; Marcisz, Katarzyna; Płóciennik, Mateusz; Obremska, Milena; Pawłowski, Dominik; Okupny, Daniel; Słowińska, Sandra; Borówka, Ryszard; Kittel, Piotr; Forysiak, Jacek; Michczyńska, Danuta J.; Lamentowicz, Mariusz

    2016-04-01

    Hydrological changes are main drivers of the processes occurring in the peatland ecosystem, e.g. organic matter accumulation and decomposition. Hydroclimatic changes in mires are caused by various non-climatic factors, such as hydroseral succession or land use changes. Central Europe, namely Poland, is characterized by a transitional climate with influence o both continental and Atlantic air masses, which makes a this region a very sensitive to climate change. Here we explore a potential of multidisciplinary approach in reconstruction of past climate change and particularly hydroclimatic conditions which control in Sphagnum peatland ecosystem. We reconstructed 3300 years (between 3,500 BC and 200 BC) history of development of Rąbień mire using several biotic proxies (pollen, plant macrofossils, testate amoebae, Cladocera, Chironomidae) and geochemistry. Study site - Rąbień mire (area 42 ha) is located in central Poland and it is protected nature reserve. The origin of the mire depression is connected with the development of the thermokarst basin isolated by dunes. Rąbień mire is limnogenic, i.e. formed by the process of terrestrialisation of a water body and thickness of biogenic deposits is 6.2 m (440 cm of lacustrine sediment and 180 cm of peat). Our results demonstrate the high potential of Rąbień peat record for reconstructing the palaeohydrological dynamics. The studied time interval is characterized by two pronounced dry periods: ~2,500 to ~1,700 cal. BC and ~800 to ~600 cal. BC, and two periods of significant increases in water table: ~1,100 to ~800 cal. BC and ~600 to ~250 cal. BC. The timing of the wet shift at 600 cal. BC corresponds to wet periods in different sites from Central and Eastern Europe. Our investigation reveals a complex pattern of proxies, what might be linked to the past atmospheric circulation patterns. Extreme hydroclimatic conditions most possibly had a direct impact on the functioning of peatland ecosystems. What has been

  14. Biofiltration of isopentane in peat and compost packed beds

    SciTech Connect

    Wang, Z.; Govind, R.

    1997-05-01

    Commercially available biofiltration systems have used natural bioactive materials in packed beds due to low media cost and easy availability. Detailed understanding and modeling of biofiltration systems are lacking in existing literature. Experimental studies on the isopentane treatment in air using peat- and compost-packed beds were conducted with inlet isopentane concentrations of 360 to 960 ppmv, and empty-bed gas-phase residence times of 2 to 10 min. High removal efficiencies (>90%) were achieved at low contaminant concentrations (<500 ppmv) and large empty-bed gas-phase residence times (>8 min). For both peat and compost biofilters, there was an optimal water content that gave the highest removal efficiency. For higher water content, mass transfer of isopentane through the liquid phase controlled the biofiltration removal efficiency. At low water content, irreversible changes in the bioactivity of peat and compost occurred, resulting in an irrecoverable loss of removal efficiency. Increases in biofilter bed temperature from 25 to 40 C improved the removal efficiency. A mathematical model incorporating the effect of water content and temperature was developed to describe the packed-bed biofilter performance. Model predictions agreed closely with experimental data.

  15. Contribution of peat fires to the 2015 Indonesian fires

    NASA Astrophysics Data System (ADS)

    Kaiser, Johannes W.; Heil, Angelika; Wooster, Martin J.; van der Werf, Guido R.

    2016-04-01

    Indonesia experienced widespread fires and severe air quality degradation due to smoke during September and October 2015. The fires are thought to have originated from the combination of El-Niño-induced drought and human activities. Fires ignited for land clearing escaped into drained peatlands and burned until the onset of the monsoonal rain. In addition to the health impact, these fires are thought to have emitted large amounts of greenhouse gases, e.g. more than Japan over the entire year. The Copernicus Atmosphere Monitoring Service (CAMS) has detected and quantified the fires with the Global Fire Assimilation System (GFAS) and the smoke dispersion with the Chemistry-Integrated Forecasting System (C-IFS) in near real time. GFAS and C-IFS are constrained by satellite-based observations of fire and smoke constituents, respectively. The distinction between peat and above-ground fires is a crucial and difficult step in fire emission estimation as it introduces errors of up to one order of magnitude. Here, we quantify the contribution of peat fires to the total emission flux of the 2015 Indonesian fires by (1) using an improved peat map in GFAS and (2) analysing the observed diurnal cycle of the fire activity as represented in a new development for GFAS. Furthermore, we link the fires occurrence to economic activity by analysing the coincidence with concessions for palm oil plantations and other industrial forest uses.

  16. Field Estimation of Macropore Functioning and Surface Hydraulic Conductivity in a Fen Peat

    NASA Astrophysics Data System (ADS)

    Baird, Andrew J.

    1997-03-01

    A limitation of existing models of water and solute movement in fen peats is that they fail to represent processes in the unsaturated zone. This limitation is largely due to a lack of data on the hydraulic properties of unsaturated peat, in particular the relationship between hydraulic conductivity (K) and pressure head (). A tension infiltrometer was used to measure K() of a fen peat in Somerset, England. It was found that macropores could be important in water and solute movement in this soil type. It was also found that (i) variability of K in this peat was less than that reported for other peats and mineral soils, and (ii) the K data were better described by a log-normal distribution than a normal distribution in accord with findings from other peat and mineral soils. Recommendations on improving the understanding of water and solute movement in the unsaturated zone of this soil type are made.

  17. Climate sensitivity and macronutrient regulation of peat decomposition

    NASA Astrophysics Data System (ADS)

    Marshall, Rachel; Ostle, Nick; McNamara, Niall; Baggs, Elizabeth

    2013-04-01

    peatland nutrient status and the potential for labile C substrates to stimulate (prime) decomposition of the peat organic matter. Using 13C labelled glucose and hemicellulose compounds we observed significant differences in the amount and rate of microbial substrate use between peats with differing nutrient status. Nutrient addition experiments were used with labelled C substrates to investigate the role of N and P limitation in enhancing or restricting priming effects. This is one of the first studies to use 13C substrates to examine potential priming effects in peat soil and it provides an insight into the importance of priming mechanisms in peat decomposition. This work explicitly links soil microbial responses to temperature and nutrient manipulations with microbial community structure allowing us to observe how microbial communities mediate soil C losses in peat soils. Disentangling the complex interactions between soil microbial community, C and nutrient limitation of decomposition is essential for predicting the vulnerability of different peatland ecosystems to climate driven changes.

  18. Peat: a natural repository for low-level radioactive waste

    SciTech Connect

    Thomas, E.D.

    1985-12-01

    A study has been initiated to evaluate the possibility of using peat as a natural repository for the disposal of low-level radioactive waste. One aspect of this study was to determine the retentive properties of the peat through measurements of the distribution coefficients (K/sub d/) for Am-241, Ru-106, Cs-137, Co-57, and Sr-85 in two layers of mountain top peat bogs from Lefgren's, NY, and Spruce Flats, PA. These K/sub d/ values were then compared to literature values of various sediment/water systems at similar environmental conditions. Am-241, Ru-106, Co-57, and Sr-85 attained distribution coefficients in the organic rich layers of the bogs two orders of magnitude greater than those obtained previously at pH 4.0. Although, the Cs-137 sorbed strongly to the inorganic rich layer of the Spruce Flats, PA, bog, the K/sub d/ values obtained for this isotope were, again, comparable or higher than those reported previously at pH 4.0, indicating the greater retentive properties of the peat. A chromatographic ''theoretical plate'' model was used to describe the field migration of Cs-137. The advection and diffusion coefficients were higher in the Lefgren's Bog, NY, than those obtained for the Spruce Flats Bog, PA. These field data were substantiated by the lower Cs-137 K/sub d/ values determined in the laboratory for the Lefgren's Bog, NY, compared to the Spruce Flats Bog. Although this model gave a good indication of the field migration, it neglected the process of sorption as defined by the sorption isotherm. Based on the time series data on distribution ratio measurements, a Cameron-Klute type of sorption isotherm was indicated, with rapid equilibrium initially superimposed onto a slower first order linear reversible equilibrium. This sorption isotherm can then be used in the final form of a model to describe the migration of radionuclides in a peat bog. 19 refs., 15 figs., 10 tabs.

  19. 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

  20. 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.

  1. Thermal properties of degraded lowland peat-moorsh soils

    NASA Astrophysics Data System (ADS)

    Gnatowski, Tomasz

    2016-04-01

    Soil thermal properties, i.e.: specific heat capacity (c), thermal conductivity (K), volumetric heat capacity (C) govern the thermal environment and heat transport through the soil. Hence the precise knowledge and accurate predictions of these properties for peaty soils with high amount of organic matter are especially important for the proper forecasting of soil temperature and thus it may lead to a better assessment of the greenhouse gas emissions created by microbiological activity of the peatlands. The objective of the study was to develop the predictive models of the selected thermal parameters of peat-moorsh soils in terms of their potential applicability for forecasting changes of soil temperature in degraded ecosystems of the Middle Biebrza River Valley area. Evaluation of the soil thermal properties was conducted for the parameters: specific heat capacity (c), volumetric heat capacities of the dry and saturated soil (Cdry, Csat) and thermal conductivities of the dry and saturated soil (Kdry, Ksat). The thermal parameters were measured using the dual-needle probe (KD2-Pro) on soil samples collected from seven peaty soils, representing total 24 horizons. The surface layers were characterized by different degrees of advancement of soil degradation dependent on intensiveness of the cultivation practises (peaty and humic moorsh). The underlying soil layers contain peat deposits of different botanical composition (peat-moss, sedge-reed, reed and alder) and varying degrees of decomposition of the organic matter, from H1 to H7 (von Post scale). Based on the research results it has been shown that the specific heat capacity of the soils differs depending on the type of soil (type of moorsh and type of peat). The range of changes varied from 1276 J.kg‑1.K‑1 in the humic moorsh soil to 1944 J.kg‑1.K‑1 in the low decomposed sedge-moss peat. It has also been stated that in degraded peat soils with the increasing of the ash content in the soil the value of

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

    SciTech Connect

    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.

  3. Prenatal effects of peat combustion products and afobazole correction thereof in the rat progeny.

    PubMed

    Gorbatova, D M; Nemova, E P; Solomina, A S; Durnev, A D; Seredenin, S B

    2015-03-01

    Female outbred albino rats were daily subjected to forced inhalations of peat smoke (4 cores packed with a mixture of peat (70%) and wood pulp (30%); 0.46 g, pH ≥ 5.5) per se and in combination with oral afobazole (anxiolytic) on days 1-20 of pregnancy. Exposure to peat smoke inhibited body weight gain in pregnant rats, caused an increase of postimplantation deaths, reduction of fetal weights, and an increase in the number of hematomas and hemorrhages in fetuses. Afobazole in doses of 1 and 10 mg/kg reduced significantly the untoward effects of peat smoke on fetal development. PMID:25778654

  4. Feedstock characteristics and preparation for peat gasification. Annual report, January-December 1980

    SciTech Connect

    Punwani, D.V.; Aspinall, F.; Loftons, S.M.

    1981-08-01

    The report describes the work conducted to prepare updated peat resource maps and to conduct quantitative economic and environmental assessments of a few selected peat harvesting, dewatering, and beneficiation alternatives. In the task on peat resources, maps of seven states (Florida, Illinois, Maine, Michigan, North Carolina, Ohio, and Wisconsin) have been completed. A number of peat harvesting system designs have been ranked according to their technical merits. A preliminary economic comparison of four peat dewatering systems has been made. A description of a beneficiation (wet-carbonization) process and a preliminary economic estimate for producing beneficiated peat is presented. Recent developments in both thermal and biological conversion of peat to substitute natural gas (SNG) are described. The major air and water pollution emission rates from a peat gasification plant producing 250 billion Btu/day of SNG have been estimated. Detailed environmental scenarios have been prepared for three peat bogs typical of those in the Upper Midwest, Northeast, and Southeast United States. Preliminary cost estimates for harvested peatland reclamation options have been made.

  5. Peat deposits in Panama: Their potential for use in energy applications

    SciTech Connect

    Ramirez, A.; Thayer, G.; Cohen, A.D.; Allen, A.

    1986-12-01

    A major peak bog has been discovered in the Changuinola area of Panama. The bog averages 8-m deep, is thought to be 82 km/sup 2/, in area and the peat has an ash content of about 4%. It is estimated that this size peat bog could support a 30-MW power plant for 360 years. Preliminary cost estimates for using the peat in an electrical power plant give an estimated cost of electricity of 0.09$US/kWh if wet mining is used and 0.079$US/kWh if milled peat is used. 2 refs., 4 figs.

  6. 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.

  7. Physiological Changes in Rhizobia after Growth in Peat Extract May Be Related to Improved Desiccation Tolerance

    PubMed Central

    Wilkes, Meredith A.; Deaker, Rosalind

    2013-01-01

    Improved survival of peat-cultured rhizobia compared to survival of liquid-cultured cells has been attributed to cellular adaptations during solid-state fermentation in moist peat. We have observed improved desiccation tolerance of Rhizobium leguminosarum bv. trifolii TA1 and Bradyrhizobium japonicum CB1809 after aerobic growth in water extracts of peat. Survival of TA1 grown in crude peat extract was 18-fold greater than that of cells grown in a defined liquid medium but was diminished when cells were grown in different-sized colloidal fractions of peat extract. Survival of CB1809 was generally better when grown in crude peat extract than in the control but was not statistically significant (P > 0.05) and was strongly dependent on peat extract concentration. Accumulation of intracellular trehalose by both TA1 and CB1809 was higher after growth in peat extract than in the defined medium control. Cells grown in water extracts of peat exhibit morphological changes similar to those observed after growth in moist peat. Electron microscopy revealed thickened plasma membranes, with an electron-dense material occupying the periplasmic space in both TA1 and CB1809. Growth in peat extract also resulted in changes to polypeptide expression in both strains, and peptide analysis by liquid chromatography-mass spectrometry indicated increased expression of stress response proteins. Our results suggest that increased capacity for desiccation tolerance in rhizobia is multifactorial, involving the accumulation of trehalose together with increased expression of proteins involved in protection of the cell envelope, repair of DNA damage, oxidative stress responses, and maintenance of stability and integrity of proteins. PMID:23603686

  8. Properties and structure of peat humic acids depending on humification and precursor biota in bogs

    NASA Astrophysics Data System (ADS)

    Klavins, Maris; Purmalis, Oskars

    2013-04-01

    Humic substances form most of the organic component of soil, peat and natural waters, but their structure and properties very much differs depending on their source. The aim of this study is to characterize humic acids from raised bog peat profiles to evaluate the homogeneity of humic acids isolated from the bog bodies and study peat humification impact on properties of humic acids. A major impact on the structure of peat humic acids have raised bog biota (dominantly represented by bryophytes of different origin) void of lignin. For characterization of peat humic acids their elemental (CHNOS), functional (-COOH, phenolic OH) analysis, spectroscopic characterization (UV, fluorescence, FTIR, 1H NMR, CP/MAS 13C NMR, ESR) and degradation studies (Py-GC/MS) were done. Peat humic acids (HA) have an intermediate position between the living organic matter and coal organic matter and their structure is formed in a process in which more labile structures (carbohydrates, amino acids, etc.) are destroyed, but thermodynamically more stable aromatic and polyaromatic structures emerge. Comparatively, the studied peat HAs are at the start of the transformation process of living organic matter. Concentrations of carboxyl and phenolic hydroxyl groups changes depending on the depth of peat from which HAs have been isolated: and carboxylic acidity is increasing with depth of peat location and the humification degree. The ability to influence the surface tension of peat humic acids isolated from a well-characterized bog profile demonstrates dependence on age and humification degree. With increase of the humification degree and age of humic acids, their molecular complexity and ability to influence surface tension decreases; even so, the impact of the biological precursor (peat-forming bryophytes and plants) can be identified.

  9. Methanogenesis and CO 2 exchange in an ombrotrophic peat bog

    NASA Astrophysics Data System (ADS)

    Lloyd, David; Thomas, Katie L.; Benstead, Julie; Davies, Kevin L.; Lloyd, Siôn H.; Arah, Jonathan R. M.; Stephen, Karl D.

    Methanogenesis was studied in water-saturated peat cores from hollows in Ellergower Moss, New Galloway, Scotland. The concentration of CH 4, increased with depth from 0.8 μM at the surface to reach a plateau of 500 μM at 14 cm; at this depth CO 2 concentrations often reached 10 fold those of CH 4. O 2 decreased from near air saturation to less than 10 nM at 6 cm depth. Argon transport from the top of the core downwards occurred more rapidly (D=0.8-7×10 -8 m 2 s -1, dependent on depth) than could be accounted for by simple diffusion through the peat. Vascular plants ( Molinia, Eriophorum and Carex) had well-developed roots and were adapted to water-logged conditions in that they possessed extensive aerenchymatous lacunae throughout their roots, shoots and leaves. As well as facilitating O 2 diffusion downwards to submerged tissues, this system enables rapid diffusion upwards of CH 4. This process of gaseous transport in vascular plants is subject to control by stomata. Emission rates of CO 2 and CH 4 thus show diurnal rhythms at constant temperature. Free-run of CO 2 oscillation in the dark at 15 cm depth indicates circadian clock control. The temperature sensitivity of CH 4 emission is remarkably high ( Q10=3.0 between 10 and 20°C in the dark); in cores kept under natural conditions of temperature and daylight the daily rhythms entrain to the peat temperature cycles.

  10. Impact of prescribed burning on blanket peat hydrology

    NASA Astrophysics Data System (ADS)

    Holden, Joseph; Palmer, Sheila M.; Johnston, Kerrylyn; Wearing, Catherine; Irvine, Brian; Brown, Lee E.

    2015-08-01

    Fire is known to impact soil properties and hydrological flow paths. However, the impact of prescribed vegetation burning on blanket peatland hydrology is poorly understood. We studied 10 blanket peat headwater catchments. Five were subject to prescribed burning, while five were unburnt controls. Within the burnt catchments, we studied plots where the last burn occurred ˜2 (B2), 4 (B4), 7 (B7), or greater than 10 years (B10+) prior to the start of measurements. These were compared with plots at similar topographic wetness index locations in the control catchments. Plots subject to prescribed vegetation burning had significantly deeper water tables (difference in means = 5.3 cm) and greater water table variability than unburnt plots. Water table depths were significantly different between burn age classes (B2 > B4 > B7 > B10+) while B10+ water tables were not significantly different to the unburnt controls. Overland flow was less common on burnt peat than on unburnt peat, recorded in 9% and 17% of all runoff trap visits, respectively. Storm lag times and hydrograph recession limb periods were significantly greater (by ˜1 and 13 h on average, respectively) in the burnt catchments overall, but for the largest 20% of storms sampled, there was no significant difference in storm lag times between burnt and unburnt catchments. For the largest 20% of storms, the hydrograph intensity of burnt catchments was significantly greater than those of unburnt catchments (means of 4.2 × 10-5 and 3.4 × 10-5 s-1, respectively), thereby indicating a nonlinear streamflow response to prescribed burning. Together, these results from plots to whole river catchments indicate that prescribed vegetation burning has important effects on blanket peatland hydrology at a range of spatial scales.

  11. Biologically active preparations with a stimulating and fungicidal effect based on peat

    SciTech Connect

    Naumova, G.V.; Kosonogova, L.V.; Zhmakova, N.A.

    1995-12-31

    Peat is a source of biologically active substances, most of which are humic acids. Peat also contains a broad range of elements including iron, iodine, copper, manganese, and cobalt. A wide range of these humic acids are utilized as growth stimulators. Studies of the preparation of the humic acids are described.

  12. 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...

  13. Extensive turnover of plant nitrogen in peats from the West Siberian Lowland

    NASA Astrophysics Data System (ADS)

    Philben, M. J.; Kaiser, K.; Benner, R. H.

    2012-12-01

    Nitrogen cycling in peatlands is of great interest because N is scarce in peatlands and may limit both primary production and microbial decomposition. The amino acid hydroxyproline (Hyp) was used to determine the proportion of peat N derived from plants in two peat cores collected from the West Siberian Lowland, Russia. Hyp is an effective tracer of plant N because plants are its only significant source in peats. In addition, its reactivity is similar to that of bulk plant N, so its yield in peat can be used to quantitatively estimate plant N. The C:N ratio of the peat was very high (>70) throughout both cores. As N is assumed to be conserved while C is removed with decomposition, high C:N ratios are often interpreted as indicating relatively unaltered peat. However, Hyp yields indicate extensive turnover of plant N. Peat N was mostly plant-derived in the upper 50 cm of both cores, but declined to 30-60% in the catotelm. These results suggest that N from plant litter is rapidly utilized by microbes and incorporated into new forms. Thus despite high C:N ratios, these peats have undergone substantial alteration and decomposition. This demonstrates the organic N pool in peatlands is intensely recycled and is more dynamic than can be inferred by considering the C:N ratio alone.

  14. In situ fluidization for peat bed rupture, and preliminary economic analysis

    NASA Astrophysics Data System (ADS)

    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 l 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.

  15. Preliminary investigation of mineralogy and chemistry of peats from the Kietrz site, southern Poland

    NASA Astrophysics Data System (ADS)

    Skreczko, Sylwia; Nadłonek, Weronika; Szopa, Krzysztof

    2015-10-01

    Peat bog deposits provide a very important record of past environmental conditions, preserving biotic and abiotic processes that occurred in the vicinity of the bog. In this study, we examined three peat bog profiles from Kietrz, located in the micro-region of the Głubczycki Plateau, southern Poland. The objective of this study was to determine the type of peat occurring in this area, through examination of its mineral composition, and evaluation of the total carbon and total sulphur content. In addition, we measured peat reaction (pH) and identified floral and faunal components occurring within the peat deposits. The peat comprises primarily of fragments of fossilized plant and mollusk remains, as well as minerals (calcium sulphates, calcium carbonates, and pyrites). Additionally, an assemblage of iron oxides/hydroxides, Kfeldspar, apatite, zircon, and quartz grains was identified. A neutral and/or light alkalinity was recorded for the peat deposits, but an increase in acidity (pH) with increasing depth through each peat profile was also recorded. We observed a positive correlation between the pH and chemical composition of deposits, where a significant presence of calcite is associated with higher reaction (higher pH), whilst a lower pH is characteristic for sediments where carbonates are rare. The recognized species of mollusks are typical of shallow, fresh-water stagnant reservoirs with a high fluctuation of water level.

  16. 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...

  17. 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...

  18. 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 ...

  19. Dynamics of peat accumulation and marl flat formation in a calcareous fen, midwestern United States

    USGS Publications Warehouse

    Miner, J.J.; Ketterling, D.B.

    2003-01-01

    The age and sequence of peat accumulation were investigated at a calcareous fen in northeastern Illinois, USA. The purpose of this study was to identify the processes that form and sustain marl flats, which are areas of marl or tufa substrate within the fen that contain numerous rare plant species. Geomorphic, stratigraphic, and radiocarbon evidence was used to establish the processes and chronology of peat accumulation and erosion adjacent to each marl flat. The age of the base of the peat deposit varies greatly throughout the fen, ranging from 14,679 calibrated years before present (cal. years BP) to nearly modern, indicating that colonization of the sand and gravel substrate by peat occurred throughout the period from the Late Pleistocene to present. Adjacent to one marl flat, trends in basal peat age and thickness show that peat accumulation has progressed laterally inward from both sides, suggesting that the marl flat has been infilling with peat progressively by accumulation at the margins since at least 5,370 cal. years BP or longer. A second marl flat in the fen is surrounded by older, thick peat of differing ages on either edge and is bounded by fresh scarps, indicating that the marl flat currently is expanding laterally by erosion into the preexisting peat blanket. These two examples suggest a continuously repeating process, where erosion of the accumulated peat blanket forms a marl flat, which is later covered by peat accumulation. Trends in basal peat age elsewhere in the fen suggest that other marl flats may have existed in the past that have been completely infilled with peat. This study suggests that marl flat formation is a natural process that has been occurring for millennia, continuously creating habitat for the rare plant species that occupy marl flats. There is no evidence that the marl flats at this site are indicative of anthropogenic disturbance, so that management options for these areas are limited to maintaining the quality and quantity

  20. Variability of humic acid properties depending on their precursor material: a study of peat profiles

    NASA Astrophysics Data System (ADS)

    Klavins, Maris; Purmalis, Oskars

    2015-04-01

    Analysis of variation of peat composition, presence of trace elements in the peat and HSs within peat profiles can give information on the character of transformation of organic matter, important for C biogeochemical cycling, but also about impacts of climate change and human activities. In peat the transformation and decay process of living organic matter (humification) is retarded by the acidic and anaerobic environment, but at the same time the peat can provide information on environmental and paleo-environmental conditions of the past. The aim of the present study is to analyze the elemental and functional composition, spectral characteristics of humic acids isolated from a well characterized raised bog peat profiles to evaluate the impact of the character of humification processes on the peat HA properties. A comparative and complex characterization of humic acids (HAs) isolated from peat profiles of different origin in Latvia was carried out. Elemental and functional analysis of the isolated HAs was done, their acidity and molecular weights estimated. Spectral characterization included UV-Vis, IR, and electron spin resonance and fluorescence spectra. Structural characterization of HAs was by both 1H and 13C nuclear magnetic resonance spectra. Comparison of position of studied humic acids in the Van Krevelen graph was done, thus locating them in the biogeochemical transformation processes of organic matter. Properties of HAs isolated from the Latvian peat were compared with HA from other sources (soil, water, coal and synthetic humic substances). Major properties of peat HAs depended on their origin, indicating the importance of humification processes. HAs isolated from peat of more recent origin were more similar to soil HAs, but from older sources there was a greater degree of humification. Changes of surface tension of solutions of humic acids stress the differences in aggregation character - ability to form supramacromolecular complexes of humic substances

  1. Preliminary evaluation of environmental issues on the use of peat as an energy source

    SciTech Connect

    King, R.; Richardson, S.; Walters, A.; Boesch, L.; Thomson, W.; Irons, J.

    1980-03-14

    A study to characterize the environmental issues, that would arise from an extensive peat utilization program has been initiated. The objectives of this preliminary report are to: identify the environmental issues and potential problems; examine the significance of issues in the geographical regions where peat use could be developed; and establish a methodology by which issues can be resolved or clarified through future coordinated private, state, and federal programs. An overview of peat development including discussions on conversion technologies, extraction and harvesting procedures, and land reclamation is presented. Environmental concerns are in the areas of water resources and quality, air quality, health and safety issues, solid waste management, and land reclamation. The general environmental issues, resource availability, and attitudes associated with potential peat development in ten states, containing an estimated 90 percent of US peat resources were described. The ten states reviewed are Alaska, Minnesota, Michigan, Maine, North and South Carolina, Wisconsin, New York, Florida, and Louisiana. (DMC)

  2. Long-term purification efficiency of a wetland constructed to treat runoff from peat extraction.

    PubMed

    Karjalainen, Satu M; Heikkinen, Kaisa; Ihme, Raimo; Kløve, Bjørn

    2016-01-01

    Peat extraction increases the phosphorus, nitrogen, organic matter, suspended solids, and iron concentrations in runoff, resulting in negative effects on downstream water bodies. Wetlands are commonly used as natural cost-effective solutions to mitigate these negative effects. This study analyzed changes in the quality of runoff water from peat extraction areas and the long-term efficiency of constructed wetlands. The results indicate that the quality of runoff water changed after the initial drainage and during peat extraction. Nitrogen leached at high concentrations in the early stages of peat extraction following drainage, whereas the leaching of iron and phosphorus increased after peat extraction from deeper layers. Comparison of water quality and impurities retained immediately after treatment wetland construction and 14 years later showed that the treatment wetland remained functional, with good retention capacity, over a long period. PMID:26809932

  3. Ebullition of methane from peatlands: Does peat act as a signal shredder?

    NASA Astrophysics Data System (ADS)

    Ramirez, Jorge A.; Baird, Andy J.; Coulthard, Tom J.; Waddington, J. Michael

    2015-05-01

    Bubbling (ebullition) of greenhouse gases, particularly methane, from peatlands has been attributed to environmental forcings, such as changes in atmospheric pressure. However, observations from peat soils suggest that ebullition and environmental forcing may not always be correlated and that interactions between bubbles and the peat structure may be the cause of such decoupling. To investigate this possibility, we used a simple computer model (Model of Ebullition and Gas storAge) to simulate methane ebullition from a model peat. We found that lower porosity peat can store methane bubbles for lengthy periods of time, effectively buffering or moderating ebullition so that it no longer reflects bubble production signals. Our results suggest that peat structure may act as a "signal shredder" and needs to be taken into account when measuring and modeling ebullition.

  4. Uncertainties in peat volume and soil carbon estimated using ground penetrating radar and probing

    SciTech Connect

    Parsekian, Andrew D.; Slater, Lee; Ntarlagiannis, Dimitrios; Nolan, James; Sebestyen, Stephen D; Kolka, Randall K; Hanson, Paul J

    2012-01-01

    We evaluate the uncertainty in calculations of peat basin volume using high-resolution data . to resolve the three-dimensional structure of a peat basin using both direct (push probes) and indirect geophysical (ground penetrating radar) measurements. We compared volumetric estimates from both approaches with values from literature. We identified subsurface features that can introduce uncertainties into direct peat thickness measurements including the presence of woody peat and soft clay or gyttja. We demonstrate that a simple geophysical technique that is easily scalable to larger peatlands can be used to rapidly and cost effectively obtain more accurate and less uncertain estimates of peat basin volumes critical to improving understanding of the total terrestrial carbon pool in peatlands.

  5. Actinomycetal complexes in drained peat soils of the taiga zone upon pyrogenic succession

    NASA Astrophysics Data System (ADS)

    Zenova, G. M.; Glushkova, N. A.; Bannikov, M. V.; Shvarov, A. P.; Pozdnyakov, A. I.; Zvyagintsev, D. G.

    2008-04-01

    The number and diversity of actinomycetes in peat soils vary in dependence on the stage of pyrogenic succession. In the cultivated peat soil, the number of actinomycetes after fires decreases by three-four times, mainly at the expense of acidophilic and neutrophilic groups. An increase in the number of mycelial prokaryotes (at the expense of alkaliphilic forms) is seen on the fifth year of functioning of the pyrogenic peat soil. The species diversity of streptomycetes in peat soils also decreases after fires. An increase in the range of streptomycetal species at the expense of neutrophilic and alkaliphilic forms takes place on the fifth year of the pyrogenic succession. Parameters of the actinomycetal complex—the population density, species composition, and ecological features—are the criteria whose changes allow us to judge the state of peat soils in the course of their pyrogenic succession.

  6. Additives for cement compositions based on modified peat

    NASA Astrophysics Data System (ADS)

    Kopanitsa, Natalya; Sarkisov, Yurij; Gorshkova, Aleksandra; Demyanenko, Olga

    2016-01-01

    High quality competitive dry building mixes require modifying additives for various purposes to be included in their composition. There is insufficient amount of quality additives having stable properties for controlling the properties of cement compositions produced in Russia. Using of foreign modifying additives leads to significant increasing of the final cost of the product. The cost of imported modifiers in the composition of the dry building mixes can be up to 90% of the material cost, depending on the composition complexity. Thus, the problem of import substitution becomes relevant, especially in recent years, due to difficult economic situation. The article discusses the possibility of using local raw materials as a basis for obtaining dry building mixtures components. The properties of organo-mineral additives for cement compositions based on thermally modified peat raw materials are studied. Studies of the structure and composition of the additives are carried out by physicochemical research methods: electron microscopy and X-ray analysis. Results of experimental research showed that the peat additives contribute to improving of cement-sand mortar strength and hydrophysical properties.

  7. Hydrology of peat-forming wetlands in Scotland.

    PubMed

    Bragg, O M

    2002-07-22

    Peatlands cover approximately 14% of Scotland, although only part of this area is active (peat-forming) mire. Mires are important for the biodiversity of the specialist plant and animal communities they support. Study of mire ecosystems has revealed intimate relationships between their organic components and water, which mean that it is impossible to understand their ecology without considering hydrology. Whilst ecohydrological studies have concentrated on the internal functioning of mires, the insights gained are relevant to runoff generation in peat-covered river catchments. This paper reviews our knowledge of processes occurring in mires and relates these to wider catchment hydrology, on the basis of published information and recent research in Scotland. The influence of different types of land management is considered, and it emerges that mire is most effective in delaying storm run-off, in preventing soil erosion and in retaining inorganic nutrients when it is undrained; although there can be adverse effects on water quality under certain conditions. In the context of global warming, mire ecosystems are sensitive but at the same time robust to climate change, and thus contain archives of climatic data for the Holocene. Moreover, peatlands store significant quantities of carbon, and influence directly the concentrations of greenhouse gases in the atmosphere. Various issues related to conservation and restoration of peatland biodiversity have been addressed constructively in recent decades, although approaches and objectives are not always consistent between sites. These are reviewed, and some outstanding issues and research needs are identified. PMID:12169001

  8. Fate of silicate minerals in a peat bog

    NASA Astrophysics Data System (ADS)

    Bennett, Philip C.; Siegel, Donald I.; Hill, Barbara M.; Glaser, Paul H.

    1991-04-01

    An investigation of silicate weathering in a Minnesota mire indicates that quartz and aluminosilicates rapidly dissolve in anoxic, organic-rich, neutral- pH environments. Vertical profiles of pH, dissolved silicon, and major cations were obtained at a raised bog and a spring fen and compared. Profiles of readily extractable silicon, diatom abundance, ash mineralogy, and silicate surface texture were determined from peat cores collected at each site. In the bog, normally a recharge mound, dissolved silicon increases with depth as pH increases, exceeding the background silicon concentration by a factor of two. Silicate grain surfaces, including quartz, are chemically etched at this location, despite being in contact with pore water at neutral pH with dissolved silicon well above the equilibrium solubility of quartz. The increasing silica concentrations at circum-neutral pH are consistent with a system where silicate solubility is influenced by silica-organic-acid complexes. Silica-organic-acid complexes therefore may be the cause of the almost complete absence of diatoms in decomposed peat and contribute to the formation of silica-depleted underclays commonly found beneath coal.

  9. Peat Bogs as Hotspots for Organoarsenical Formation and Persistence.

    PubMed

    Mikutta, Christian; Rothwell, James J

    2016-04-19

    Peatlands have received significant atmospheric inputs of As and S since the onset of the Industrial Revolution, but the effect of S deposition on the fate of As is largely unknown. It may encompass the formation of As sulfides and organosulfur-bound As, or the indirect stimulation of As biotransformation processes, which are presently not considered as important As immobilization pathways in wetlands. To investigate the immobilization mechanisms of anthropogenically derived As in peatlands subjected to long-term atmospheric pollution, we explored the solid-phase speciation of As, Fe, and S in English peat bogs by X-ray absorption spectroscopy. Additionally, we analyzed the speciation of As in pore- and streamwaters. Linear combination fits of extended X-ray absorption fine structure (EXAFS) data imply that 62-100% (average: 82%) of solid-phase As (Astot: 9-92 mg/kg) was present as organic As(V) and As(III). In agreement with appreciable concentrations of organoarsenicals in surface waters (pH: 4.0-4.4, Eh: 165-190 mV, average Astot: 1.5-129 μg/L), our findings reveal extensive biotransformation of atmospheric As and the enrichment of organoarsenicals in the peat, suggesting that the importance of organometal(loid)s in wetlands subjected to prolonged air pollution is higher than previously assumed. PMID:27034028

  10. Denitrification in marl and peat sediments in the Florida everglades.

    PubMed

    Gordon, A S; Cooper, W J; Scheidt, D J

    1986-11-01

    The potential for denitrification in marl and peat sediments in the Shark River Slough in the Everglades National Park was determined by the acetylene blockage assay. The influence of nitrate concentration on denitrification rate and N(2)O yield from added nitrate was examined. The effects of added glucose and phosphate and of temperature on the denitrification potential were determined. The sediments readily denitrified added nitrate. N(2)O was released from the sediments both with and without added acetylene. The marl sediments had higher rates than the peat on every date sampled. Denitrification was nitrate limited; however, the yields of N(2)O amounted to only 10 to 34% of the added nitrate when 100 muM nitrate was added. On the basis of measured increases in ammonium concentration, it appears that the balance of added nitrate may be converted to ammonium in the marl sediment. The sediment temperature at the time of sampling greatly influenced the denitrification potential (15-fold rate change) at the marl site, indicating that either the number or the specific activity of the denitrifiers changed in response to temperature fluctuations (9 to 25 degrees C) in the sediment. It is apparent from this study that denitrification in Everglades sediments is not an effective means of removing excess nitrogen which may be introduced as nitrate into the ecosystem with supply water from the South Florida watershed and that sporadic addition of nitrate-rich water may lead to nitrous oxide release from these wetlands. PMID:16347228

  11. Electrocoagulation treatment of peat bog drainage water containing humic substances.

    PubMed

    Kuokkanen, V; Kuokkanen, T; Rämö, J; Lassi, U

    2015-08-01

    Electrocoagulation (EC) treatment of 100 mg/L synthetic wastewater (SWW) containing humic acids was optimized (achieving 90% CODMn and 80% DOC removal efficiencies), after which real peat bog drainage waters (PBDWs) from three northern Finnish peat bogs were also treated. High pollutant removal efficiencies were achieved: Ptot, TS, and color could be removed completely, while Ntot, CODMn, and DOC/TOC removal efficiencies were in the range of 33-41%, 75-90%, and 62-75%, respectively. Al and Fe performed similarly as the anode material. Large scale experiments (1 m(3)) using cold (T = 10-11 °C) PBDWs were also conducted successfully, with optimal treatment times of 60-120 min (applying current densities of 60-75 A/m(2)). Residual values of Al and Fe (complete removal) were lower than their initial values in the EC-treated PBDWs. Electricity consumption and operational costs in optimum conditions were found to be low and similar for all the waters studied: 0.94 kWh/m(3) and 0.15 €/m(3) for SWW and 0.35-0.70 kWh/m(3) and 0.06-0.12 €/m(3) for the PBDWs (large-scale). Thus, e.g. solar cells could be considered as a power source for this EC application. In conclusion, EC treatment of PBDW containing humic substances was shown to be feasible. PMID:25973580

  12. Changes in Flow and Transport Patterns in Fen Peat as a Result of Soil Degradation

    NASA Astrophysics Data System (ADS)

    Liu, Haojie; Janssen, Manon; Lennartz, Bernd

    2016-04-01

    The preferential movement of water and transport of substances play an important role in soils and are not yet fully understood especially in degraded peat soils. In this study, we aimed at deducing changes in flow and transport patterns in the course of soil degradation as resulting from peat drainage, using titanium dioxide (TiO2) as a dye tracer. The dye tracer experiments were conducted on columns of eight types of differently degraded peat soils from three sites taken both in vertical and horizontal directions. The titanium dioxide suspension (average particle size of 0.3 μm; 10 g l‑1) was applied in a pulse of 40 mm to each soil core. Twenty-four hours after the application of the tracer, cross sections of the soil cores were prepared for photo documentation. In addition, the saturated hydraulic conductivity (Ks) was determined. Preferential flow occurred in all investigated peat types. From the stained soil structural elements, we concluded that undecomposed plant remains are the major preferential flow pathways in less degraded peat. For more strongly degraded peat, bio-pores, such as root and earthworm channels, operated as the major transport domain. Results show that Ks and the effective pore network in less degraded peat soils are anisotropic. With increasing peat degradation, the Ks and cross section of effective pore network decreased. The results also indicate a strong positive relationship between Ks and number of macropores as well as pore continuity. Hence, we conclude that changes in flow and transport pathways as well as Ks with an increasing peat degradation are due to the disintegration of the peat forming plant material and decrement of number and continuity of macropores after drainage.

  13. 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.

  14. Reduced bed agglomeration by co-combustion biomass with peat fuels in a fluidized bed

    SciTech Connect

    Karin Lundholm; Anders Nordin; Marcus Oehman; Dan Bostroem

    2005-12-01

    Fluidized bed combustion is an energy conversion technology that is very suitable for biomass combustion because of its fuel flexibility and low process temperatures. However, agglomeration of bed material may cause severe operating problems. To prevent or at least reduce this, peat has been suggested as an additive to the main fuels. Nevertheless, the characteristics of peat fuels vary and there is limited information of the effect of different peat fuels and of the mechanisms behind the agglomeration prevention. The objectives of the present work were therefore to: (I) quantify the potential positive effect by co-combustion peat with forest fuels in terms of initial agglomeration temperatures; (ii) determine the amount of peat fuel that is needed to significantly reduce the agglomeration tendencies; and, if possible, (iii) elucidate the governing mechanisms. The results showed that all peat fuels prevented agglomeration in the studied interval of 760-1020{sup o}C and even as little as 5% peat fuel was found to have significant effects. The results also indicated that the mechanism of the agglomeration prevention varies between different peat fuels. Possible mechanisms are the minerals in the peat fuel retain alkali, which then is either elutriated up from the bed or captured in the bed; calcium and other refractory elements increase the melting temperature and thereby counteract the melting of alkali; and sulfur reacts with alkali metals and the alkali sulfates is either elutriated up from the bed or prevents agglomeration by increased melting temperature and lowered viscosity. Results from elemental analysis of the coating on bed particles showed that all mixtures with peat fuel resulted in a decreased or unchanged fraction of potassium and an increased fraction of aluminum in the coatings. The results also indicated a complex relationship between the fuel inorganic contents and the agglomeration process. 21 refs., 6 figs., 5 tabs.

  15. Experimental program for the development of peat gasification. Monthly status report, February 1-February 28, 1981

    SciTech Connect

    Not Available

    1981-03-01

    In Task 1 (Single-Stage Fluidized-Bed Gasification Tests), one test was conducted with Minnesota peat in the process development unit (PDU), using steam and oxygen. The test was performed at a pressure of 268 psia, a fluidization velocity of 1.0 ft/s, and an average bed temperature of 1680/sup 0/F. The objective was to determine the effects of high feed moisture content (22-weight-percent moisture) and low gasification pressure on the gasification characteristics of peat. Most of the previous tests had been conducted at a nominal pressure of 500 psia. The test was successful; about 1 hour of steady-state operation was achieved before sintering began and the test was ended. The results of a test conducted previously with Minnesota peat containing about 8-weight-percent moisture were analyzed and are presented this month. The test was conducted at an average bed temperature of 1700/sup 0/F, a pressure of 522 psia, and a steam-to-carbon feed ratio of 1.1 mol/mol; it achieved a carbon conversion of about 84%. In Task 2 (Wet-Carbonization PDU-Scale Tests), orders were placed for long-lead-time equipment for the PDU. The design and specifications for the slurry heater/cooler system and the shell-and-tube heat exchangers have been finalized. The installation of the instrumentation and the control panel for the PDU is continuing. In Task 3 (Kinetic Data on Alaska and Florida Peats), efforts were made to obtain representative samples of peats from Alaska and Florida. A sample of Florida reed-sedge peat has been obtained and is being analyzed. Samples of Alaskan peat have been taken by the company conducting the US Department of Energy (DOE) peat resource assessment work; however, they have not yet been received. In Task 4 (Effect of Dewatering Methodology on Peat Gasification), efforts to obtain peat dewatered by various methods were continued.

  16. Bog Plant Tissue Chemistry and N and S Accumulation in Peat are Influenced by Elevated N and S Deposition from Alberta Oil Sands Development

    NASA Astrophysics Data System (ADS)

    Wieder, R.; Vile, M. A.; Quinn, J.; Albright, C. M.; Scott, K. D.; Vitt, D. H.

    2013-12-01

    Development of the oil sands resource in northern Alberta, Canada has led to elevated atmospheric N and S deposition, the N coming mainly from the exhaust of diesel fueled-trucks that haul the raw oil sands from the mine sites and the S coming mainly from refining. Against a background deposition of < 1 kg/ha/yr for both N and S, at sites within 15 km of the oil sands mining region we have measured current N and S deposition to be as high as 2 and 27 kg/ha/yr. With a goal of developing monitoring tools to assess the spatial extent of elevated N and S deposition in the region, we collected leaves, needles, or whole plants of 12 bog species (lichens: Cladina mitis and Evernia mesomorpha; Sphagnum mosses: S. capillifolium and S. fuscum; a tree: Picea mariana; ericaceous shrubs: Ledum groenlandicum, Oxycoccos microcarpus and Vaccinium vitis-idaea; deciduous forbs: Rubus chamaemorus and Smilacina trifolia) from 5 bogs ranging from 11 to over 250 km from the oil sands mining area. Samples were collected on 23 dates between May and October of 2009-2012 and were analyzed for C, N, and S concentrations. Six species (C. mitis, E. mesomorpha, S. fuscum, O. microcarpus, V. vitis-idaea, and R. chamaemorus) exhibited statistically significant increases in C:N ratio with increasing distance from the oil sands mining area. Five species (C. mitis, E. mesomorpha, S. fuscum, S. capillifolium, O. microcarpus) exhibited statistically significant increases in C:S ratio with increasing distance from the oil sands mining area. For three species (S. fuscum, E. mesomorpha, O. microcarpus), N concentrations gradually and significantly increased (C:N ratios decreased) over the four years of the study, with the rate of increase as high as 1 mg/g/yr at sites in close proximity to the oil sands mining area. In contrast, S concentrations in plant tissues generally did not increase over the four years, possibly because of increasing efforts to control S emissions from stacks. Using 210Pb

  17. 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.

  18. Economics of selected energy applications of peat in Panama and Costa Rica

    SciTech Connect

    Thayer, G.R.; Ramirez E., O.; Ramirez, A.

    1989-01-01

    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 per 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.

  19. Thermal degradation of diesel-contaminated peats in an air atmosphere

    SciTech Connect

    Ghaly, R.A.; Ugursal, V.I.; Ghaly, A.E.; Mansaray, K.G.

    1999-06-01

    Peat, plant matter that is partially fossilized, is formed in poorly oxygenated wetlands where the rate at which the plant matter accumulates is greater than the rate at which it decomposes. Peat is a common solid fuel ranked among coal, coke, wood, and sugarcane bagasse. Peat has also been used to recover oil during the soil and water remediation processes. However, industrial utilization of peat in thermochemical conversion systems to liberate energy requires the knowledge of its thermal characteristics. In this study, the thermal behavior of peat (both uncontaminated and diesel-contaminated) was examined at three heating rates (10, 20, and 50 C/min) in a stationary air atmosphere using a thermogravimetric analysis technique between ambient temperature (25 C) and 600 C. The thermal degradation rate in active and passive pyrolysis zones, the initial degradation temperature, and the residual weight at 600 C were determined. Increasing the heating rate increased both the thermal degradation rate and the residual weight at 600 C and decreased the initial degradation temperature. The residual weight at 600 C was less than the ash content in all of the peat samples indicating the burnout of some of the mineral oxides, which have low melting and boiling temperatures, such as K{sub 2}O and P{sub 2}O. The results provide useful information about utilization of diesel-contaminated peat in thermochemical conversion systems, especially gasifiers, because of its high energy content and low ash content.

  20. Peat decomposition - shaping factors, significance in environmental studies and methods of determination; a literature review

    NASA Astrophysics Data System (ADS)

    Drzymulska, Danuta

    2016-03-01

    A review of literature data on the degree of peat decomposition - an important parameter that yields data on environmental conditions during the peat-forming process, i.e., humidity of the mire surface, is presented. A decrease in the rate of peat decomposition indicates a rise of the ground water table. In the case of bogs, which receive exclusively atmospheric (meteoric) water, data on changes in the wetness of past mire surfaces could even be treated as data on past climates. Different factors shaping the process of peat decomposition are also discussed, such as humidity of the substratum and climatic conditions, as well as the chemical composition of peat-forming plants. Methods for the determination of the degree of peat decomposition are also outlined, maintaining the division into field and laboratory analyses. Among the latter are methods based on physical and chemical features of peat and microscopic methods. Comparisons of results obtained by different methods can occasionally be difficult, which may be ascribed to different experience of researchers or the chemically undefined nature of many analyses of humification.

  1. Peat form and distribution – acrotelm hydrology and topographic wetness index

    NASA Astrophysics Data System (ADS)

    Kirkby, Mike; Irvine, Brian

    2015-04-01

    Away from the divide in a peat mire, steadily increasing volumes of rainwater flowing through and over the peat can only be transported by increasing surface and water table gradient, forcing development of a domed form for a raised bog. Simple models assume either a groundwater mound in which the peat surface is defined by the water table, or a surface limited by the balance between growth and decomposition. Recognised complications to the hydrology include the observations of substantial flow both close to the bog surface and through pipes within the peat mass and the near-random heterogeneity of hydraulic conductivity values in the peat. In addition the assumptions of these end member models interact, since increases in peat depth allow more water to flow through the catotelm, thereby increasing seasonal drying near the surface and raising decomposition rates. These competing factors have been built into a model which combines TOPmodel near-surface with Darcian flow at depth, creating a dynamic oxic layer within which rates of decomposition are highest. This enriched mire model, distinguishes bogs, and regions within bogs, dominated by surface or internal flow and those that are limited by growth and decomposition. The model also helps to clarify the important role of seasonality in bog growth, provides some guidance on where peat can become established, on the basis of climate and local topography, and how this may evolve as global temperatures rise.

  2. 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.

  3. 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.

  4. 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.

  5. Peat and its modification products as sorbents for remeval of metals, metalloids and nonmetallic elements

    NASA Astrophysics Data System (ADS)

    Klavins, Maris; Ansone, Linda; Robalds, Artis; Dudare, Diana

    2013-04-01

    For remediation of soils and purification of waters biosorbents 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. We have demonstrated the possibilities to use peat and its thermal treatment products for oil sorption. Peat as an oil sorbent has poor buoyancy characteristics, relatively low oil sorption capacity and low hydrophobicity. However, thermal treatment (low-temperature pyrolysis and synthesis of peat-based active coal) helps to significantly improve its sorptive characteristics. The processes and structural changes taking place during low-temperature pyrolysis have been studied by means of IR spectroscopy, thermogravimetry and scanning electron microscopy. Peat can be used also as an efficient sorbent for sorption of metallic elements as it has been demonstrated on example of Tl+, Cu2+, Cr3+, however sorption capacity in respect to nonmetallic (anionic species) elements is low. To develop such application possibilities peat, peat modified with iron compounds, iron humates were prepared and tested for sorption of arsenic 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.

  6. Products from peat processing as components of preservative materials

    SciTech Connect

    Tishina, E.A.; Bel'kevich, P.I.; Churshukov, E.S.; Lazarenko, V.P.; Lishtvan, I.I.

    1984-09-01

    This article reports on an investigation of the protective properties of resinous substances that are waste materials in the production of deresined wax. The protective properties of the resins extracted by BR-2 naphtha at 20/sup 0/C, 0/sup 0/C, and 5/sup 0/C, and also the ethanol-soluble and ethanol-insoluble components of these resins are examined. The results indicate that the peat wax resins do not show any corrosivity with respect to copper. At elevated temperatures, the resins are as good as the commercial additive Akor-1 in protective efficiency, and their alcohol-soluble components are better than the Akor-1. It is concluded that the good compatibility of the resins with mineral oils and their high level of protection make them suitable for use in liquid preservative formulations for the temporary corrosion protection of metal items.

  7. 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

  8. Experimental Investigation of the Effect of Production Factors on the Properties of Peat Briquettes

    NASA Astrophysics Data System (ADS)

    Piralishvili, Sh. A.; Birfel‧d, A. A.; Stepanov, E. G.; Mikhailov, A. S.; Spesivtseva, N. S.

    2016-03-01

    The influence of the compacting pressure and moisture content of a raw peat material on such properties of fuel briquettes as the density, volume heat of combustion, compressive mechanical strength, hardness, and water absorption has been determined. Based on the results of investigations, regression dependences, characterizing the functional relationship between the noted compaction conditions and the quality indices of peat fuel, have been obtained. The optimal values of the compacting pressure and moisture content of peat that correspond to the most energy-efficient compaction regimes have been substantiated.

  9. Impact of subjacent rocks at the water and air regime of the depleted peat deposits

    NASA Astrophysics Data System (ADS)

    Rakovich, V. A.

    2009-04-01

    At the depleted peat deposits (after peat extraction), where the residual layer of peat with the thickness of about 0,5 meters is laid at the well water permeable rocks, vegetation typical for dry conditions is developed in case of good drainage conditions; birch trees, willow, alder-trees and buckthorn prevail in this vegetation. Water and air regime is characterized here by good aeration with prevailing of oxidative processes. If water regime is regulated, these depleted peat areas are suitable for agricultural and forest lands; however, necessity of transformation of these depleted lands into forest and agricultural lands must be ecologically and economically justified. If the residual layer of peat with the thickness of 0,05-0,3 m is based at the sapropel or peat sapropel, contrast amphibiotic water and air regime with strong fluctuation of oxidative and restoration process depending on the weather conditions is formed; this regime is formed without artificial increase of the ground waters level. This does not allow bog vegetation or vegetation typical for dry conditions to develop. Thus, within 20 and more years after completion of peat extraction, such areas are not covered by vegetation in spite of favorable agro-chemical qualities of peat layer and favorable for vegetation chemical composition of soil and ground waters. Depleted peat deposits, that are based at the sapropel, are not suitable for agricultural use, because agricultural vegetation requires stable water and air regime with good aeration and oxidative and restoration potential within 400-750 mV. Contrast amphibiotic water and air regime of the depleted peat deposits that are based at sapropel excludes possibility to use them as agricultural lands. Because of this reason, areas with residual peat layer that are based at sapropel are not suitable for forest planting. Due to periodic increase of ground waters level, rot systems of the plants can not penetrate into the required depth, and mechanical

  10. 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

  11. Characterisation and distribution of deposited trace elements transported over long and intermediate distances in north-eastern France using Sphagnum peatlands as a sentinel ecosystem

    NASA Astrophysics Data System (ADS)

    Meyer, Caroline; Diaz-de-Quijano, Maria; Monna, Fabrice; Franchi, Marielle; Toussaint, Marie-Laure; Gilbert, Daniel; Bernard, Nadine

    2015-01-01

    Trace elements in the form of particulate matter can be transported downwind from their emission sources and may have negative effects on human health and ecosystems. The transport of trace elements is often studied by monitoring their accumulation in mosses. The aim of this study was to characterise and describe the distribution of deposited trace elements transported over long and intermediate distances in north-eastern France, a location far from the main emission sources. We analysed the trace element accumulation in Sphagnum capillifolium in 54 ombrotrophic peatlands distributed in six regions of France (Alps, Jura, Massif Central, Morvan, Rhône corridor and Vosges). The concentrations of Al, Cd, Cr, Cu, Fe, Pb, Ti, V, and Zn in the surface were determined in three replicate samples of Sphagnum within each peatland. The enrichment factors calculated using Ti as the element of reference clearly exhibited a predominant anthropogenic origin for Cd, Cu, Pb, and Zn, although the concentrations were relatively low compared to those found in other studies. The isolation of the peatlands from any fixed and traffic emission source suggests an intermediate and/or long-distance transport of the pollutants from their emission sources. The structure of the compositional dataset was explored using a covariance biplot. The first score was used as a synthetic indicator of the origin of the deposits and the degree of contamination of each peatland. This new index showed that the Vosges and the Alps were the regions most affected by high enrichment of trace elements, particularly Pb and Cd. The erosion of soils highly contaminated by former mining and smelting activities in the Vosges and the polluted cities and busy highways in the Alps may account for these distributions. The Jura was the least affected region sampled, and the other regions presented intermediate anthropogenic deposits. This study provides valuable information concerning the management and protection of

  12. Investigating variability of biogenic gas dynamics in peat soils using high temporal frequency hydrogeophysical methods

    NASA Astrophysics Data System (ADS)

    Wright, William J.

    Peat soils are known to be a significant source of atmospheric greenhouse gasses. However, the releases of methane and carbon dioxide gasses from peat soils are currently not well understood, particularly since the timing of the releases are poorly constrained. Furthermore, most research work performed on peatlands has been focused on temperate to sub-arctic peatlands, while recent works have suggested that gas production rates from low-latitude peat soils are higher than those from colder climates. The purpose of the work proposed here is to introduce an autonomous Ground Penetrating Radar (GPR) method for investigating the timing of gas releases from peat soils at the lab scale utilizing samples originating from Maine and the Florida Everglades, and at the field scale in a Maine peatland. Geophysical data are supported by direct gas flux measurements using the flux chamber method enhanced by timelapse photography, and terrestrial LiDAR (TLS) monitoring surface deformation.

  13. Environmental aspects of alternative wet technologies for producing energy/fuel from peat. Final report

    SciTech Connect

    Smith, R.T.

    1981-05-01

    Peat in situ contains up to 90% moisture, with about 50% of this moisture trapped as a colloidal gel. This colloidal moisture cannot be removed by conventional dewatering methods (filter presses, etc.) and must be removed by thermal drying, solvent extraction, or solar drying before the peat can be utilized as a fuel feedstock for direct combustion or gasification. To circumvent the drying problem, alternative technologies such as wet oxidation, wet carbonization, and biogasification are possible for producing energy or enhanced fuel from peat. This report describes these three alternative technologies, calculates material balances for given raw peat feed rates of 1000 tph, and evaluates the environmental consequences of all process effluent discharges. Wastewater discharges represent the most significant effluent due to the relatively large quantities of water removed during processing. Treated process water returned to the harvested bog may force in situ, acidic bog water into recieving streams, disrupting local aquatic ecosystems.

  14. Peat soil organic matter composition depth profiles - is the diplotelmic model real?

    NASA Astrophysics Data System (ADS)

    Boothroyd, Ian; Clay, Gareth; Moody, Catherine; Archer, Elaine; Dixon, Simon; Worrall, Fred

    2016-04-01

    Measures of bulk density and organic matter composition provide important insights into peat formation, degradation and hydrology as well as carbon and nutrient cycles, and indeed underpin the diplotelmic model of peat formation. This study presents soil core data from 23 upland and lowland peat sites across the United Kingdom. A series of soil cores up to ~3m depth were analysed for bulk density, gross heat value (energy content) and carbon, hydrogen, nitrogen and oxygen composition. Atomic ratios of C/N, H/C and O/C were used as indicators of the origin and quality of soil organic matter. Results show no consistent soil depth profiles evident across multiple sites, this challenges whether historical interpretations of peat soil formation and structure are appropriate.

  15. Pressate from peat dewatering as a substrate for bacterial growth. [Rhizopus arrhizus; Xanthomonas campestris; Aureobasidium

    SciTech Connect

    Mulligan, C.N.; Cooper, D.G.

    1985-07-01

    This study considered the possibility of using water expressed during the drying of fuel-grade peat as a substrate for microbial growth. Highly humified peat pressed for 2.5 min at 1.96 MPa produced water with a chemical oxygen demand of 690 mg/liter. Several biological compounds could be produced by using the organic matter inexpressed peat water as a substrate. These included polymers such as chitosan, contained in the cell wall of Rhizopus arrhizus, and two extracellular polysaccharides, xanthan gum and pullulan, produced by Bacillus subtilis grown in the expressed water. Small additions of nutrients to the peat pressate were necessary to obtain substantial yields of products. The addition of peptone, yeast extract, and glucose improved production of the various compounds. Biological treatment improved the quality of the expressed water to the extent that in an industrial process it could be returned to the environment.

  16. Analysing flow patterns in degraded peat soils using TiO2 dye

    NASA Astrophysics Data System (ADS)

    Liu, Haojie; Lennartz, Bernd

    2014-05-01

    Dye tracing is a valuable method for studying the flow patterns in soils. However, limited information is available on water flow and solute transport pathways in dark colored peat soils because the frequently used Brilliant Blue FCF dye does not visibly stain the soil. In this study, we were aiming at testing the suitability of Titanium dioxide (TiO2) as a dye tracer for dark peat soils. The objectives were to quantify the physical properties of different degraded peat soils and visualize the flow patterns. Soil samples were collected from two low-lying fen sites, where the top soil was highly degraded, while lower horizons were less decomposed. Dye tracer experiments were conducted at both sites by applying a TiO2 suspension (10 g/l) with a pulse of 40 mm. Soil profiles were prepared for photo documentation the following day. It was found that the physical and hydraulic properties of peat were significantly influenced by the degree of peat decomposition and degradation. Higher decomposed and degraded peat soils had a higher bulk density, lower organic matter content and lower porosity. Moreover, higher decomposition and degradation resulted in a lower saturated hydraulic conductivity as long as investigated samples originated from the same site. In addition, degraded peat soils showed less anisotropy than un-degraded peat. It turned out that TiO2 is a suitable dye tracer to visualize the flow paths in peat soils. Although dye patterns differed within the same plot and between different plots, most of the flow patterns indicated a preferential flow situation. The distribution of TiO2 in the soil profile, as analyzed from 5 by 5 cm grid cells, compared to the distribution of bromide, which was applied along with the dye confirming the suitability of the dye tracer. Un-decomposed plant structures, such as wood branches and leaves, were identified as the major preferential flow path in un-degraded peat. For degraded peat, bio-pores, such as root and earthworm

  17. 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

  18. Environmental factors affecting the low temperature isomerization of homohopanes in acidic peat deposits, central China

    NASA Astrophysics Data System (ADS)

    Huang, Xianyu; Meyers, Philip A.; Xue, Jiantao; Gong, Linfeng; Wang, Xinxin; Xie, Shucheng

    2015-04-01

    Progressively more evidence reveals the abundant occurrence of the C31 homohopane with a 17α, 21β-configuration (C31 αβ) in immature peats. This compound is commonly considered to be an indicator of thermal maturity in petroleum source rocks, but in peats it has also been interpreted to reflect the oxidation and subsequent decarboxylation reactions of bacteriohopanepolyols with microbially mediated epimerization at C-17 that is catalyzed by the acidic peat conditions. To learn more about the environmental factors that affect the low-temperature isomerization of homohopanes, we investigated the distribution patterns of homohopanes in a well-studied peat core from the Dajiuhu peatland, central China, together with data from modern surface peat samples from Dajiuhu and three other locations. From comparison with paleotemperature and paleohydrologic records in the peat core, we hypothesize that the ratio of C31 αβ hopane relative to the ββ isomer (C31 αβ/ββ) is mainly influenced on a centennial to millennial timescale by ambient temperature with a secondary effect from redox conditions that are defined by peatland water levels. The surface peat samples revealed that relatively high C31 αβ/ββ values occurred under pH < 6. These results suggest that pH is indeed an important factor in the low-temperature isomerization of C31 homohopanes, although the magnitude of the pH effect may be less than those of ambient temperature and redox conditions. In both surface peat and peat horizons from the Dajiuhu peatland, the amount of the C31 αβ compound with R configuration relative to that with S configuration (C31 R/S) varied closely with C31 αβ/ββ, suggesting that the epimerization at both C-17 and C-22 may happen synchronously and at similar rates. This study reveals that the isomerization of homohopanes has the potential to reflect paleoenvironmental changes in acidic peat deposits. In addition, acidic peat samples investigated in this and previous studies

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

    SciTech Connect

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

    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 (>150 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.

  20. Incorporation of radiometric tracers in peat and implications for estimating accumulation rates.

    PubMed

    Hansson, Sophia V; Kaste, James M; Olid, Carolina; Bindler, Richard

    2014-09-15

    Accurate dating of peat accumulation is essential for quantitatively reconstructing past changes in atmospheric metal deposition and carbon burial. By analyzing fallout radionuclides (210)Pb, (137)Cs, (241)Am, and (7)Be, and total Pb and Hg in 5 cores from two Swedish peatlands we addressed the consequence of estimating accumulation rates due to downwashing of atmospherically supplied elements within peat. The detection of (7)Be down to 18-20 cm for some cores, and the broad vertical distribution of (241)Am without a well-defined peak, suggest some downward transport by percolating rainwater and smearing of atmospherically deposited elements in the uppermost peat layers. Application of the CRS age-depth model leads to unrealistic peat mass accumulation rates (400-600 g m(-2) yr(-1)), and inaccurate estimates of past Pb and Hg deposition rates and trends, based on comparisons to deposition monitoring data (forest moss biomonitoring and wet deposition). After applying a newly proposed IP-CRS model that assumes a potential downward transport of (210)Pb through the uppermost peat layers, recent peat accumulation rates (200-300 g m(-2) yr(-1)) comparable to published values were obtained. Furthermore, the rates and temporal trends in Pb and Hg accumulation correspond more closely to monitoring data, although some off-set is still evident. We suggest that downwashing can be successfully traced using (7)Be, and if this information is incorporated into age-depth models, better calibration of peat records with monitoring data and better quantitative estimates of peat accumulation and past deposition are possible, although more work is needed to characterize how downwashing may vary between seasons or years. PMID:24946030

  1. Appraisal of peat thickness using combined GPR and terrestrial lidar survey

    NASA Astrophysics Data System (ADS)

    Vsemirnova, Ekaterina; Wilkinson, Maxwell; Carle, Joël; Jarvis, Zak; Miller, Chris; Jones, Richard; Warburton, Jeff

    2013-04-01

    Estimating the depth of peat cover has traditionally been carried out manually using hand-held probe rods, and more recently using methods of near surface geophysics, principally ground-penetrating radar (GPR). These studies provide an important basis for evaluating carbon storage in organic mire ecosystems. However, peatlands often represent a challenge when acquiring GPR over large areas (on the order of 100s ha) of rough terrain; processing of GPR data is also often difficult due to local variations in topography. Little Woolden Moss is > 100 ha peatland site west of Manchester, UK. The site is crossed with numerous shallow ditches and some deeper drainage ditches, and a number of linear raised areas of peat. Peat extraction has taken place on the site over many years, and still being actively worked. A detailed study of peat thickness and base-peat topography was carried out in late 2012. The site was surveyed using a MALÅ RAMAC GPR and 200 MHz unshielded antenna linked to differential GPS. The antennae were housed within a bespoke rough terrain sledge. The data, collected along over 40 profiles with length between 200 and 600 m, were post-processed using MALÅ RadExplorer and Seismic Unix software, including digitising of peat depth layers. Static terrain corrections were derived from terrestrial lidar data acquired at the site using a Riegl LMS-Z40i scanner, integrated with GPS readings provided at the time of GPR survey. The survey enabled detailed maps of base peat elevation and terrain corrected peat thickness to be produced in ArcGIS.

  2. Characterizing peat palm forest degradation in the Peruvian Amazon from space and on the ground

    NASA Astrophysics Data System (ADS)

    Hergoualc'h, Kristell; Gutierrez-Velez, Victor Hugo; van Lent, Jeffrey; Verchot, Louis Vincent

    2016-04-01

    Peru has the second largest area of peatlands in the Tropics however little is known on how the biogeochemical cycle of its peat forests can be affected through anthropogenic intervention. The most representative land cover on peat is a Mauritia flexuosa-dominated palm swamp forest which has been under human pressure over decades due the high demand for the M. flexuosa fruit often collected by cutting down the entire palm. Degradation of these carbon-dense forests can severely affect emissions of greenhouse gases and contribute to climate change. The objectives of this research were to assess the impacts on soil trace gas fluxes and biomass carbon stocks of peat palm swamp forest degradation and to explore the potential of remote sensing methods combined with field measurements to map the distribution of peat palm swamp forest according degradation levels. Results suggest a shift in forest composition from palm- to woody-tree dominated forest following degradation. We also found that human intervention in peat palm swamp forest can translate into substantial reductions in tree carbon stocks with a decrease in initial biomass (above and below-ground) stocks (118.3 ± 1.1 Mg C ha-1) by 26 and 44% following medium and high degradation. Preliminary results suggest high and low soil CH4 and CO2 emission rates on average, as compared to Southeast Asian peat swamp forests whereas N2O emissions are of the same magnitude. Degradation seems to disrupt soil respiration mainly through micro-climatic changes induced by reduced canopy cover. The analysis indicates a good potential to discriminate areas of peat palm swamp forest with different levels of degradation from other land covers, suggesting the feasibility of monitoring peat palm swamp forest degradation using remote sensing analyses.

  3. Controls on in situ oxygen and dissolved inorganic carbon dynamics in peats of a temperate fen

    NASA Astrophysics Data System (ADS)

    Estop-AragonéS, Cristian; Knorr, Klaus-Holger; Blodau, Christian

    2012-06-01

    Changes in hydrological conditions are expected and may alter carbon cycling in peatlands. Peat aeration with water table change has not commonly been investigated, and the water table is often assumed to constitute the oxic-anoxic boundary in peat. We analyzed temperature, moisture, oxygen (O2), and carbon dioxide (CO2) concentrations in profiles of a temperate fen during two seasons. A drying-rewetting cycle and flooding were induced and compared to controls. The response of moisture and water table position varied greatly and was related to gradients of peat compaction and ash content. Background drought raised air-filled porosity (AFP) to a maximum of 15%-38% in shallow peat and experimental drought up to 50%. Decline in water table and soil moisture broadly led to O2 penetration and CO2 degassing, and rewetting and flooding led to anoxic conditions and CO2 accumulation in peat pore water. In dense peat with ≥20% ash content the unsaturated zone remained partly low in oxygen, however, and up to 5% AFP and 20 cm above water table O2 concentrations frequently remained below 50 μmol L-1. Moderately intense and short drying did not induce substantial oxygen penetration in the compacted soil profiles. The likelihood of the presence of oxygen in the peat was predicted by logistic regression using water table and ash content or bulk density as predictors (p < 0.0005). The model is potentially useful for predicting the position of the redoxcline in peat deposits and may assist in improving statistical models of trace gas emission from peatlands.

  4. Assessment of the peat resources of Florida, with a detailed survey of the northern everglades

    SciTech Connect

    Griffin, G.M.; Wieland, C.C.; Hood, L.Q.; Goode, R.W. III; Sawyer, R.K.; McNeill, D.F.

    1982-01-01

    Available data, including previous publications, modern soil surveys, and detailed coring in the Northern Everglades for this project have been used to update information on Florida's peat resources. It is now estimated that Florida could, if no other constraints existed, produce 606 million tons of moisture-free fuel-grade peat, which may yield approximately 10.0 x 10/sup 15/ Btu of energy. These estimates are much lower than previously published projections for the state. The principal effort of this survey was in the largest peat region of the state, the Northern Everglades of Palm Beach and adjacent counties, where more than 800 core holes were drilled. Based on analyses of these cores, the Northern Everglades is now estimated to contain 191 million tons of moisture-free peat, with a potential energy yield of 2.98 x 10/sup 15/ Btu. These values are considerably less than previously published estimates, probably due to bacterial oxidation and other forms of drainage-induced subsidence in the Everglades agricultural areas. The present fuel-peat resources of the Northern Everglades occur in 19 separate deposits. Of these, the deposits in the Port Mayaca, Bryant, Six Mile Bend, and Loxahatchee Quadrangles comprise the highest concentration of the resource. These lands are generally privately owned and used for sugar cane and other crops, and the conversion of these lands to peat removal seems unlikely. It seems even less likely that the extensive peat deposits within the Loxahatchee National Wildlife Refuge will be available for fuel use, barring a dire national emergency. The utilization of peat as a fuel must be approached with caution and careful study; large scale use may require state or federal action. 34 references.

  5. 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

  6. Peat analyses in the Hudson Bay Lowlands using ground penetrating radar

    NASA Technical Reports Server (NTRS)

    Pelletier, R. E.; Davis, J. L.; Rossiter, J. R.

    1991-01-01

    The use of ground penetrating radar (GPR) as a means to determine peak thickness and estimate peat volume in the Hudson Bay Lowlands of Canada is examined. Ground-based and airborne GPR data were acquired so as to extrapolate measurements to larger scales. While the ground-based measurements did an excellent job in determining peat depth, the airborne techniques did a fair job a low altitudes and demonstrated great promise with additional system engineering changes.

  7. Influence of climatic and hydrological factors on structure and composition of peat from northern wetland territories with low anthropogenic impact.

    PubMed

    Parfenova, L N; Selyanina, S B; Trufanova, M V; Bogolitsyn, K G; Orlov, A S; Volkova, N N; Ponomareva, T I; Sokolova, T V

    2016-05-01

    Northern wetlands ecosystems play an important role in the hydrological balance of neighboring areas, where they act as chemical barriers against anthropogenic and technogenic contaminations. Studied region is well known for quantity of peat deposits and the volume of peat resources. Peat can be considered as a highly informative marker for assessing change in environmental conditions. The study presents the results of the first investigation of peat samples, collected from representative ecosystems of northern wetland territories with low anthropogenic impact. Component and element composition of various peat types were studied in a relation to hydrologic, climate and sampling conditions. It was found out that organic and ash contents are more dependent on the type of the bog, than geographic location. Climatic factors are more important for the formation of bitumen. The degradation degree in peat increases proportionally to content of humates. High content of biogenic and lithogenic elements was observed in transition- and low-moor peat. The content of trace elements in peat samples do not depend on the type of the peat. The structural properties of peat were studied by the light microscopy, AFM and dynamic light scattering. It was determined that the conformation of studied peat samples is characterized by elements of asymmetry. The observed particles in the solutions exist in dynamic equilibrium with separated globular macromolecules. The size of these nanoparticles is comparable with the size of the particles of other biopolymers of similar nature. Swelling of peat in liquid water was studied. The relationship between structural specificities, origin of peat and its maximum degree of swelling was found. The degree of swelling can be used as structural-sensitive parameter in further research. PMID:26874767

  8. Peat biogasification development program. Quarterly progress report No. 5, for period October 1 - December 31, 1980

    SciTech Connect

    Wise, Dr., Donald L.

    1981-01-15

    Progress is reported in the peat biogasification development program. The objective of the research is to compile the necessary data for the design and operation of a peat anaerobic digestion process development unit. Five areas are addressed: pretreatment information; anaerobic digestion; evaluation of waste streams; process model development and economic analysis; and planning for the process development unit. During the reporting period extensive data was taken for the development of the predictive process model. A number of batch and continuous pretreatment experiments were completed and analyzed. The four samples being analyzed through solvent extration were completed, and the results are presented. Work on High Pressure Liquid Chromatography continued, and the development of the gradient elution solvent system was completed with encouraging results. Pretreated peat has been batch fermented; the continuously oxidized peat has shown conversions of close to 30%. This is significantly higher than the conversions for the batch oxidized peat. Continuous digesters have been in operation for approximately one month. Development of a predictive process model for the three phases of peat biogasification, solubilization, oxidation, and fermentation, continued with very good results. The models for solubilization and oxidation were developed and experimental data are being gathered for the fermentation phase of the process model. (DMC)

  9. Interactions between peat and salt-contaminated runoff in Alton Bog, Maine, USA

    NASA Astrophysics Data System (ADS)

    Pugh, Alexander L.; Norton, Stephen A.; Schauffler, Molly; Jacobson, George L.; Kahl, Jeffrey S.; Brutsaert, Willem F.; Mason, Charles F.

    1996-07-01

    Year round, concentrations of base cations (Ca, Mg, Na, and K) and Cl - in surface and groundwater decline exponentially away from Interstate 95, a four-lane asphalt highway which bisects Alton Bog, a poor fen in Penobscot County, Maine, USA. The increased concentrations close to the highway are caused primarily by runoff of road-salt and weathering products of road-bed fill. Concentration ratios, constant with time, between base cations and H + at individual sites suggest that cation exchange reactions between peat and water achieve a state of equilibrium. These ratios change systematically with increasing distance from the highway, indicating systematic changes in the character of the peat exchange surfaces. The major change is a decrease in the occupancy of exchange sites by Na away from the road. These relationships and inferred processes have been duplicated with laboratory experiments. Base saturation of the peat, dominated by Ca, decreases with distance from the highway. Thus, in the short term, peat-water equilibration exerts strong controls on the water chemistry, particularly ion ratios. Long term exposure to elevated concentrations of Ca, Mg, and NaCl in the shallow ground waters has altered the peat chemistry. Availability of plant nutrients (Ca, Mg, and K) has been generally increased by the weathering of road-bed fill and equilibration of the NaCl salt with the peat.

  10. Applications of scanning electron microscopy to the study of mineral matter in peat

    SciTech Connect

    Raymond, R. Jr.; Andrejko, M.J.; Bardin, S.W.

    1983-01-01

    Scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) have been used for in situ analysis of minerals in peats by combining methods for producing oriented microtome sections of peat with methods for critical point drying. The combined technique allows SEM analysis of the inorganic components and their associated botanical constituents, along with petrographic identification of the botanical constituents. In peat deposits with abundant fluvial- or marine-derived minerals, one may use the above technique and/or medium- or low-temperature ashing followed by x-ray diffraction to readily identify the various mineral components. However, in some freshwater environments the scarcity of non-silica minerals makes the above techniques impractical. By separating the inorganic residues from the peat, one can isolate the non-silica mineral matter in the SEM for analysis by EDS. Furthermore, such separation allows SEM analysis of features and textures of both silica and non-silica mineral particles that might otherwise be unidentifiable. Results indicate the occurrence of detritial minerals in both Okefenokee and Snuggedy Swamp peats, the presence of authigenic or diagenetic minerals growing within peats, and dissolution features on freshwater sponge spicules that may account for the absence of spicules in Tertiary lignites.

  11. The Auchenorrhyncha fauna of peat bogs in the Austrian part of the Bohemian Forest (Insecta, Hemiptera).

    PubMed

    Holzinger, Werner E; Schlosser, Lydia

    2013-01-01

    The first overview on the Auchenorrhyncha fauna of peat bogs of the Austrian Bohemian Forest is presented. Seven oligotrophic peat bog sites were studied in 2011 by suction sampler ("G-Vac") and 93 Auchenorrhyncha species (with 7465 adult specimens) were recorded. Eleven species (about 18 % of the individuals) are tyrphobiontic or tyrphophilous. The relative species abundance plot is not very steep; the six most abundant species represent 50 % of the individuals. The most common species is Conomelus anceps (17 % of the individuals). Compared to the whole Austrian Auchenorrhyncha fauna, the fauna of peat bogs comprises distinctly more univoltine species and more species hibernating in nymphal stage. Densities of adult Auchenorrhyncha in peat bogs are low in spring (about 10-60 individuals per m²) and high in July, with up to 180 (±50) individuals per m². Disturbed peat bogs have higher species numbers and higher Auchenorrhyncha densities in total, but lower numbers and densities in peat bog specialists. PMID:24039517

  12. Extraction and identification of volatile organic substances (VOS) from Scottish peat cores

    NASA Astrophysics Data System (ADS)

    Beckmann, Manfred; Lloyd, David

    The degradation of organic matter in peat bogs is complex and not yet well understood. Recent investigations of the trace gases CO 2 and CH 4 focussed on the impact of these greenhouse gases on global warming. However, there have to be metabolic intermediates between complex organic structures (i.e., humic acids) and gaseous end products (CH 4, CO 2, N 2, NO x and H 2S) other than water-soluble substances (i.e., aromatic acids, amino acids, fatty acids). Deoxygenation during microbial decomposition of plant material also produces anoxic conditions that favor the formation of kinetically stable hydrocarbons. In this study, volatile organic substances (VOS) in peat bogs were investigated using two techniques: purge-and-trap and closed-loop stripping. Coupled gas chromatography-mass spectroscopy analysis revealed mainly branched hydrocarbons (C 8H 18) in concentrations up to 260 nM in peat pore-water. Additionally, alkylated benzenes were found in concentrations of up to 464 nM, in the peat pore-water, and up to 23 pptv in the headspace of peat cores. However, one-third of all the compounds in the complex VOS-fraction extracted from the peat system remain to be identified, especially those substances containing oxygen.

  13. 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

  14. Biochar from deinking paper sludge as a peat replacement in growing media preparation

    NASA Astrophysics Data System (ADS)

    Gil, Eva; Méndez, Ana; Paz-Ferreiro, Jorge; Fernández, José Manuel; Plaza, César; Gascó, Gabriel

    2015-04-01

    Nowadays, there is an important trend in Europe for peat replacement with biochar in growing media formulation in order to reduce the environmental impact of peat exploitation. One evidence is the the creation of a working group on peat replacement within the framework of an EU COST action Biochar as option for sustainable resource management funded by the European Union. The use of biochar can reduce the environmental impact peat uses and also it can diminish the economic cost of different growing media ingredients as coir, bark or green waste compost in soil-less cultivation. The objective of this work was to study the use of biochar from deinking paper sludge in the formulation of growing media. For this reason, peat and coir were replaced by prepared biochar. Hydrophysical and chemical properties of different substrates were tested. At the same time, plant growth assay was designed. Results shown that is possible to use biochar to replace peat in growing media formulation obtaining similar crop yields.

  15. Experimental early-stage coalification of a peat sample and a peatified wood sample from Indonesia

    USGS Publications Warehouse

    Orem, W.H.; Neuzil, S.G.; Lerch, H.E.; Cecil, C.B.

    1996-01-01

    Experimental coalification of a peat sample and a buried wood sample from domed peat deposits in Indonesia was carried out to examine chemical structural changes in organic matter during early-stage coalification. The experiment (125 C, 408 atm lithostatic pressure, and 177 atm fluid pressure for 75 days) was designed to maintain both lithostatic and fluid pressure on the sample, but allow by-products that may retard coalification to escape. We refer to this design as a geologically open system. Changes in the elemental composition, and 13C NMR and FTIR spectra of the peat and wood after experimental coalification suggest preferential thermal decomposition of O-containing aliphatic organic compounds (probably cellulose) during early-stage coalification. The elemental compositions and 13C NMR spectra of the experimentally coalified peat and wood were generally similar to those of Miocene coal and coalified wood samples from Indonesia. Yields of lignin phenols in the peat and wood samples decreased following experimental coalification; the wood sample exhibited a larger change. Lignin phenol yields from the experimentally coalified peat and wood were comparable to yields of lignin phenols from Miocene Indonesian lignite and coalified wood. Changes in syringyl/vanillyl and p-hydroxy/vanillyl ratios suggest direct demethoxylation as a secondary process to demethylation of methoxyl groups during early coalification, and changes in lignin phenol yields and acid/aldehyde ratios point to a coupling between demethoxylation processes and reactions in the alkyl side chain bonds of the ??-carbon in lignin phenols.

  16. Estimating methane gas production in peat soils of the Florida Everglades using hydrogeophysical methods

    NASA Astrophysics Data System (ADS)

    Wright, William; Comas, Xavier

    2016-04-01

    The spatial and temporal variability in production and release of greenhouse gases (such as methane) in peat soils remains uncertain, particularly for low-latitude peatlands like the Everglades. Ground penetrating radar (GPR) is a hydrogeophysical tool that has been successfully used in the last decade to noninvasively investigate carbon dynamics in peat soils; however, application in subtropical systems is almost non-existent. This study is based on four field sites in the Florida Everglades, where changes in gas content within the soil are monitored using time-lapse GPR measurements and gas releases are monitored using gas traps. A weekly methane gas production rate is estimated using a mass balance approach, considering gas content estimated from GPR, gas release from gas traps and incorporating rates of diffusion, and methanotrophic consumption from previous studies. Resulting production rates range between 0.02 and 0.47 g CH4 m-2 d-1, falling within the range reported in literature. This study shows the potential of combining GPR with gas traps to monitor gas dynamics in peat soils of the Everglades and estimate methane gas production. We also show the enhanced ability of certain peat soils to store gas when compared to others, suggesting that physical properties control biogenic gas storage in the Everglades peat soils. Better understanding biogenic methane gas dynamics in peat soils has implications regarding the role of wetlands in the global carbon cycle, particularly under a climate change scenario.

  17. GAM & RF for 3D mapping of multinomial peat properties.

    NASA Astrophysics Data System (ADS)

    Poggio, Laura; Gimona, Alessandro; Aalders, Inge; Morrice, Jane; Hough, Rupert

    2013-04-01

    Different statistical methods have been proposed for fitting the empirical quantitative function linking the soil information to the scorpan factors, while taking into account the spatial structure of the data . Regression kriging extends the methods of kriging and co-kriging and it has been further extended by the use of GAMs (Generalized Additive Models) with the estimation of uncertainty. When multinomial data are modelled, advanced non-parametric methods, such as CART (Classification and Regression Tree), can be used. CARTs have been used widely to estimate soil properties. Bagging trees and Random Forest (RF) approaches have among the best performances among CART methods. CARTs have been used in DSM applications, While RF have often been used in ecological modelling, fewer examples exist in DSM, such as soil erosion occurrence, soil types prediction and soil organic carbon content. In this paper we propose a methodology to map multinomial peat properties in 3D space with a combination of GAMs and RF. The methodology was applied to the humification (according to the VonPost classification) classes in a bog (18 km2) in the north-east of Scotland. A large survey campaign was carried out in 1955 and humification information were collected at 125 points. In order to integrate the information from the GAM in the RT, a series of binary GAMs were fitted using DEM-derived information as covariates. The binary GAMs were fitted assigning 1 if the class considered was present at the location, 0 if the class considered was absent. The probability predictions resulting from the binary GAMs, were included in the pool of covariates used for the RT together with other ancillary covariates. The model diagnostics had a fair to good agreement between measured and modelled values (K statistics). The probability predictions resulting from the binary GAMs proved to be important variables, increasing the agreement of the model. The obtained spatial distribution of values on the

  18. Hydrological Simulation of Runoff from Peat Harvesting Areas Using DRAINMOD

    NASA Astrophysics Data System (ADS)

    Mohammadighavam, Shahram; Kløve, Bjørn

    2014-05-01

    Peatland drainage and harvesting cause considerable impacts on runoff water quantity and quality. A crucial water quality problem is leaching of nutrients and sediment that occur after summer rainfall and leaching of acid water after groundwater level drawdown on peatlands overlaying acid sulphate soils. Groundwater fluctuations and drain runoff are important parameters that should be better predicted and monitored for load prediction. Also performance and efficiency of drainage network and different water treatment methods depend on good prediction of these parameters during design phase. In order to prevent and control pollution from drained peatlands, The DRAINMOD model has been developed for soils with shallow water table (Skaggs, 1980). The model simulates hourly hydrological response to rainfall using soil characteristics, drainage specifications and climatological data as input. The main objective of this research is to test the model for hydrological simulation of groundwater level fluctuations and estimation the amount of drained water in two peat harvesting areas in north of Finland. In order to collecting data different loggers are installed in each area to observe groundwater level, drainage water and rain continuously since summer of 2012. Several soil profiles were taken from mentioned sites and tested in the laboratory and some measuring were done in the field to determine soil characteristics as well. Water table depth (WTD) data that were collected during observation period are used for model calibration and validation. Some outliers occurred for certain events, but most simulated values of WTD are matched with observed data, both in terms of timing and quantity, thus, it can be concluded that the model performed satisfactorily for peat harvesting sites. The model allow to simulate daily amount of infiltration, evapotranspiration, runoff, drainage water and water table depth that are useful in the design of control structures, storage and sediment

  19. Carbon dioxide emissions through oxidative peat decomposition on a burnt tropical peatland.

    PubMed

    Hirano, Takashi; Kusin, Kitso; Limin, Suwido; Osaki, Mitsuru

    2014-02-01

    In Southeast Asia, a huge amount of peat has accumulated under swamp forests over millennia. Fires have been widely used for land clearing after timber extraction, thus land conversion and land management with logging and drainage are strongly associated with fire activity. During recent El Niño years, tropical peatlands have been severely fire-affected and peatland fires enlarged. To investigate the impact of peat fires on the regional and global carbon balances, it is crucial to assess not only direct carbon emissions through peat combustion but also oxidative peat decomposition after fires. However, there is little information on the carbon dynamics of tropical peat damaged by fires. Therefore, we continuously measured soil CO2 efflux [peat respiration (RP)] through oxidative peat decomposition using six automated chambers on a burnt peat area, from which about 0.7 m of the upper peat had been lost during two fires, in Central Kalimantan, Indonesia. The RP showed a clear seasonal variation with higher values in the dry season. The RP increased logarithmically as groundwater level (GWL) lowered. Temperature sensitivity or Q10 of RP decreased as GWL lowered, mainly because the vertical distribution of RP would shift downward with the expansion of an unsaturated soil zone. Although soil temperature at the burnt open area was higher than that in a near peat swamp forest, model simulation suggests that the effect of temperature rise on RP is small. Annual gap-filled RP was 382 ± 82 (the mean ± 1 SD of six chambers) and 362 ± 74 gC m(-2)  yr(-1) during 2004-2005 and during 2005-2006 years, respectively. Simulated RP showed a significant negative relationship with GWL on an annual basis, which suggests that every GWL lowering by 0.1 m causes additional RP of 89 gC m(-2)  yr(-1) . The RP accounted for 21-24% of ecosystem respiration on an annual basis. PMID:23775585

  20. Controls on peat hydraulic conductivity: bridging the gap between models and measurements

    NASA Astrophysics Data System (ADS)

    Morris, Paul J.; Baird, Andy J.; Belyea, Lisa R.

    2015-04-01

    Peat hydraulic properties such as saturated hydraulic conductivity (Ksat) are variable in space and time. A broadly accepted but poorly understood relationship between peat decomposition and Ksat is highly influential on the behaviour of models of peatland development, but existing data do not allow this relationship to be parameterised satisfactorily. Previous empirical studies have typically used simple metrics of time-integrated decomposition such as fibre content, von Post score or light transmission (humification) to predict Ksat. By contrast, peatland development models represent the state of peat decomposition as a more abstract fraction of remaining mass. As such, a gap exists between the requirements of simulation models and the available empirical data - a gap that we seek to address. We collected fourteen shallow (~ 0.5 m long, 0.1 m diameter) peat cores from a Swedish raised bog. Our sampling locations comprised two vegetation microhabitats, hummocks and hollows (n = 7 for each), combined factorially with two locations - the flat, treeless, central bog plateau (n = 8) and the treed, sloping bog margin (n = 6). In the laboratory we split the cores into 0.06 m depth intervals and measured horizontal Ksat and dry bulk peat carbon to nitrogen concentration ratios (C:N). Following a published method we used these C:N values to approximate the state of peat decomposition (fractional mass remaining) for depth intervals deeper than ~ 0.1 m. We used a step-up procedure to fit a linear mixed-effects (LME) model to the data, so as to predict log10 (Ksat) from two continuous predictor variables, depth and our C:N-derived approximation of fractional mass remaining; and two categorical predictors, microhabitat (hummock, hollow) and location (central plateau, bog margin). The LME model predicts that log10 (Ksat) declines linearly with increasing depth below the surface (p < 0.001) and with increasing peat decomposition (p = 0.012); and that it is greater in hummock

  1. Impacts of peat restoration on peak flow characteristics of upland headwater catchments

    NASA Astrophysics Data System (ADS)

    Allott, Tim; Evans, Martin; Agnew, Clive; Milledge, Dave; Pilkington, Mike; Maskill, Rachael

    2014-05-01

    As part of the current focus on ecosystem services provided by peatlands, there is renewed interest in the hydrology of upland blanket peats and more specifically in the hydrological changes associated with peat erosion and restoration. Peat restoration has often been cited as having potential benefits for downstream flood risk through the reduction of peak flows and increases in storm hydrograph lag times. However, evidence of the impacts of peatland restoration practices on storm hydrology and downstream discharge peaks has been limited by lack of measurement of flow response following restoration programmes. This paper reports a hydrological monitoring programme associated with the restoration of a blanket peatland in the Peak District, UK through the practices of erosion gully blocking and the re-vegetation of bare peat. The main component of the project is a before-after-control-impact (BACI) study on three hectare-scale eroded, bare peat catchments, two of which have been restored and one of which is acting as an unmodified control. Monitoring commenced in early summer 2010, and restoration of the experimental sites by reseeding and gully blocking took place between July 2011 and March 2012. To complement the main study, a broader spatial comparison of the hydrological behaviour of catchments with different degradation and restoration conditions has been made, including (i) an intact reference peatland, (ii) the eroded/bare peat sites, and (iii) a 'late stage' restored area of peatland which was re-vegetated in 2003. Results reveal significant differences between the storm hydrograph characteristics of intact, eroded and restored catchments consistent with the hypotheses that (a) peat erosion significantly decreases storm flow lag times and increases storm flow peaks in these peatland systems and (b) peat restoration reverses these effects. Associated overland flow data suggest that gully blocking and re-vegetation within gully systems are crucial controls on

  2. Peat-fire-related air pollution in Central Kalimantan, Indonesia.

    PubMed

    Hayasaka, Hiroshi; Noguchi, Izumi; Putra, Erianto Indra; Yulianti, Nina; Vadrevu, Krishna

    2014-12-01

    The past decade marked record high air pollution episodes in Indonesia. In this study, we specifically focus on vegetation fires in Palangkaraya located near a Mega Rice Project area in Indonesia. We analyzed various gaseous air pollution data such as particulate matter (PM10), SO2, CO, O3, and NO2 study region. We also conducted elemental analysis at two different sites. Results from 2001 to 2010 suggested the longest hazardous air pollution episode during 2002 lasting about 80 days from mid-August to late-October. Maximum peak concentrations of PM10, SO2, CO, and O3 were also observed during 2002 and their values reached 1905, 85.8, 38.3, and 1003×10(-6) gm(-3) respectively. Elemental analysis showed significant increase in concentrations during 2011 and 2010. Satellite retrieved fires and weather data could explain most of the temporal variations. Our results highlight peat fires as a major contributor of photochemical smog and air pollution in the region. PMID:25087200

  3. Warming Effects Enzyme Turnover During Decomposition of Subtropical Peat

    NASA Astrophysics Data System (ADS)

    Sihi, D.; Inglett, P.; Inglett, K. S.

    2015-12-01

    Extracellular enzymes are the proximate agents for organic matter degradation, but the turnover rate of enzymes is often assumed in most decomposition models without direct observations. Here, we assess turnover rates of C (ß-D-glucosidase), N (Leucine aminopeptidase), and P (Phosphomonoesterase) degrading enzymes by spiking commercially available enzymes to the dissolved organic matter of two subtropical peats incubated at 15°C and 25°C and monitoring of net activity of spiked enzymes (i.e. the difference between the spiked and the non-spiked samples) over time. Turnover rates of all three enzymes were greater in the samples incubated at 25°C (ranged between 0.006 hr-1 to 0.014 hr-1) as compared to those incubated at 15°C (ranged between 0.002 hr-1 to 0.009 hr-1). Concentrations of dissolved organic matter were positively correlated with the turnover rates (R2 ranged between 0.71-0.77) of all enzyme groups. To our knowledge, this is the first attempt to evaluate the turnover rates of enzymes in wetland soils as a function of warming and dissolved organic matter concentration. The findings suggest that warming-induced changes in the size of soil enzyme pool due to direct (by increasing protease activity) and indirect (by increasing concentrations of dissolved organic matter) effects on their turnover rates has potential to alter soil C stocks in a warmer world.

  4. Radioactive waste disposal in simulated peat bog repositories

    SciTech Connect

    Schell, W.R.; Massey, C.D.

    1987-01-01

    The Low Level Radioactive Waste Policy Act of 1980 and the Low Level Radioactive Waste Policy Amendments Act of 1985 have required state governments to be responsible for providing low-level waste (LLW) disposal facilities in their respective areas. Questions are (a) is the technology sufficiently advanced to ensure that radioactive wastes can be stored for 300 to 1000 yr without entering into any uncontrolled area. (b) since actual experience does not exist for nuclear waste disposal over this time period, can the mathematical models developed be tested and verified using unequivocal data. (c) how can the public perception of the problem be addressed and the potential risk assessment of the hazards be communicated. To address the technical problems of nuclear waste disposal in the acid precipitation regions of the Northern Hemisphere, a project was initiated in 1984 to evaluate an alternative method of nuclear waste disposal that may not rely completely on engineered barriers to protect the public. Certain natural biogeochemical systems have been retaining deposited materials since the last Ice Age (12,000 to 15,000 yr). It is the authors belief that the biogeochemical system of wetlands and peat bogs may provide an example of an analogue for a nuclear waste repository system that can be tested and verified over a sufficient time period, at least for the LLW disposal problem.

  5. Topsoil Removal in a Restored Peat Wetland: an Experimental Study

    NASA Astrophysics Data System (ADS)

    Hausman, C. E.; Fraser, L.; de Szalay, F. A.

    2005-05-01

    Topsoil removal is a common practice in wetland restoration projects for eliminating the weed seed bank, any persistent herbicides or pesticides, as well as lowering the soil surface closer to the water table. In 2000, a peat wetland that was drained 85 years ago for agriculture was restored by removing 40-50 cm of topsoil, seeding wetland plants, and reestablishing wetland hydrology. In 2004, six 100m2 scraped plots and six adjacent 100m2 unscraped control plots were sampled in North and South fields. Plant percent cover and aboveground biomass was measured in each plot. Depth to the water table was greater in the North field because this field had a higher elevation than the South field, which was partially submerged. Total biomass was greater in the North field than in the South. In the North field, species diversity and richness were higher in treatment plots than control plots, but there was no difference in the South field. Dominant species were different between the control and treatment plots and between North and South fields. These results indicate that both water levels and topsoil removal have dramatic impacts on plant community establishment in restored wetlands.

  6. Micromonospora humi sp. nov., isolated from peat swamp forest soil.

    PubMed

    Songsumanus, Apakorn; Tanasupawat, Somboon; Thawai, Chitti; Suwanborirux, Khanit; Kudo, Takuji

    2011-05-01

    A novel actinomycete, strain P0402(T), was isolated from peat swamp forest soil collected in Thailand. Its taxonomic position was determined by using a polyphasic taxonomic approach. The chemotaxonomic characteristics of this strain matched those of the genus Micromonospora, i.e. the presence of meso-diaminopimelic acid and N-glycolyl muramic acid in the peptidoglycan, whole-cell sugar pattern D, phospholipid type II, and cellular fatty acid type 3b. Phylogenetic analysis based on 16S rRNA gene sequences revealed a close relationship between strain P0402(T) and Micromonospora coxensis JCM 13248(T) (99.0 % similarity), Micromonospora eburnea JCM 12345(T) (99.0 %), Micromonospora marina JCM 12870(T) (98.9 %), Micromonospora halophytica JCM 3125(T) (98.7 %), Micromonospora chalcea JCM 3031(T) (98.7 %), Micromonospora purpureochromogenes JCM 3156(T) (98.6 %) and Micromonospora aurantiaca JCM 10878(T) (98.5 %). It could be clearly distinguished from these type strains based on low levels of DNA-DNA relatedness and phenotypic differences. On the basis of the data presented, strain P0402(T) is suggested to represent a novel species of the genus Micromonospora, for which the name Micromonospora humi sp. nov. is proposed. The type strain is P0402(T) ( = JCM 15292(T)  = PCU 315(T)  = TISTR 1883(T)). PMID:20562246

  7. 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

  8. Feedstock characteristics and preparation for peat gasification. Volume III: task 13. Final report Jul 80-Jul 81

    SciTech Connect

    Punwani, D.V.; Aspinall, F.; Lofton, S.M.

    1982-07-01

    This report describes the work conducted by the Institute of Gas Technology, Dravo Corporation, and Williams Brothers Engineering Company during Phase II of the two-phase program. The objective of Phase I was to review the literature and identify needs in the areas of resources, harvesting, dewatering, beneficiation, gasification, and environmental studies. The results of Phase I have been previously reported (PB81-222275). The objectives of Phase II are to prepare updated peat resource maps and to conduct quantitative economic and environmental assessments of a few selected peat harvesting, dewatering, and beneficiation alternatives. In the task on peat resources, maps of fourteen states have been completed. A number of peat harvesting system designs have been ranked according to their technical merits and a preliminary economic assessment has been made of a wet harvesting method. A preliminary economic comparison of four peat dewatering systems has been made. A description of a beneficiation (wet-carbonization) process and a preliminary economic estimate for producing beneficiated peat is presented. Recent developments in both thermal and biological conversion of peat to SNG are described. The major air and water pollution emission rates from a peat gasification plant producing 250 billion Btu/day of SNG have been estimated. Detailed environmental scenarios have been prepared for three peat bogs typical of those in the Upper Midwest, Northeast, and Southeast United States. Preliminary cost estimates for harvested peatland reclamation options have been made.

  9. Feedstock characteristics and preparation for peat gasification. Volume II: task 9. Final report Jul 80-Jul 81

    SciTech Connect

    Punwani, D.V.; Aspinall, F.; Lofton, S.M.

    1982-07-01

    This report describes the work conducted by the Institute of Gas Technology, Dravo Corporation, and Williams Brothers Engineering Company during Phase II of the two-phase program. The objective of Phase I was to review the literature and identify needs in the areas of resources, harvesting, dewatering, beneficiation, gasification, and environmental studies. The results of Phase I have been previously reported (PB81-222275). The objective of Phase II are to prepare updated peat resource maps and to conduct quantitative economic and environmental assessments of a few selected peat harvesting, dewatering, and beneficiation alternatives. In the task on peat resources, maps of fourteen states have been completed. A number of peat harvesting system designs have been ranked according to their technical merits and a preliminary economic assessment has been made of a wet harvesting method. A preliminary economic comparison of four peat dewatering systems has been made. A description of a beneficiation (wet-carbonization) process and a preliminary economic estimate for producing beneficiated peat is presented. Recent developments in both thermal and biological conversion of peat to SNG are described. The major air and water pollution emission rates from a peat gasification plant producing 250 billion Btu/day of SNG have been estimated. Detailed environmental scenarios have been prepared for three peat bogs typical of those in the Upper Midwest, Northeast, and Southeast United States. Preliminary cost estimates for harvested peatland reclamation options have been made.

  10. Lateral carbon fluxes and CO2 outgassing from a tropical peat-draining river

    NASA Astrophysics Data System (ADS)

    Müller, D.; Warneke, T.; Rixen, T.; Müller, M.; Jamahari, S.; Denis, N.; Mujahid, A.; Notholt, J.

    2015-07-01

    Tropical peatlands play an important role in the global carbon cycle due to their immense carbon storage capacity. However, pristine peat swamp forests are vanishing due to deforestation and peatland degradation, especially in Southeast Asia. CO2 emissions associated with this land use change might not only come from the peat soil directly, but also from peat-draining rivers. So far, though, this has been mere speculation, since there was no data from undisturbed reference sites. We present the first combined assessment of lateral organic carbon fluxes and CO2 outgassing from an undisturbed tropical peat-draining river. Two sampling campaigns were undertaken on the Maludam river in Sarawak, Malaysia. The river catchment is covered by protected peat swamp forest, offering a unique opportunity to study a peat-draining river in its natural state, without any influence from tributaries with different characteristics. The two campaigns yielded consistent results. Dissolved organic carbon (DOC) concentrations ranged between 3222 and 6218 μmol L-1 and accounted for more than 99 % of the total organic carbon (TOC). Radiocarbon dating revealed that the riverine DOC was of recent origin, suggesting that it derives from the top soil layers and surface runoff. We observed strong oxygen depletion, implying high rates of organic matter decomposition and consequently CO2 production. The measured median pCO2 was 7795 and 8400 μatm during the two campaigns, respectively. Overall, we found that only 26 ± 15 % of the carbon was exported by CO2 evasion, while the rest was exported by discharge. CO2 outgassing seemed to be moderated by the short water residence time. Since most Southeast Asian peatlands are located at the coast, this is probably an important limiting factor for CO2 outgassing from most of its peat-draining rivers.

  11. Effects of Some Environmental Factors on Growth Characteristics of Candida utilis on Peat Hydrolysates.

    PubMed

    Chang, F H

    1985-01-01

    Samples of peat from Pine Island and Brookston bogs in Minnesota were hydrolyzed with various concentrations of HCl or H(2)SO(4) solutions, before or after debituminization (an extraction process used to remove waxy materials, bitumens, from peat), to produce peak hydrolysates as growth substrates for Candida utilis. Hydrolysates were neutralized with concentrated NaOH solution to pH 3.5, 4.5, 5.0, 5.5, 6.0, and 7.0. The precipitated humates were removed by filtration. The resulting peat hydrolysates were amended with reagent-grade K(2)HPO(4), K(2)SO(4), and MgSO(4), 200, 100, and 50 mg per liter of peat hydrolysate, respectively. The debituminized peat produced more total nitrogen (TN) and reducing substances (RS) than the nondebituminized peat. Peat hydrolysates produced by HCl solutions contained slightly higher RS and TN than those produced by H(2)SO(4) solutions; however, the latter were better growth substrates than the former. The yield coefficients in both H(2)SO(4) and HCl hydrolysates initially decreased at 12 to 24 h and then increased gradually over the remaining incubation period (24 to 96 h). As TN and RS were increased, an increase in cell density, biomass, and productivity was observed. In contrast, a decrease in specific growth rate occurred as the RS and TN were increased. The generation time of C. utilis was affected by the concentrations of RS and TN. A peak substrate yield coefficient was found at pH 5.0 in HCl hydrolysates and at pH 6.0 to 6.5 in H(2)SO(4) hydrolysates. Good linear correlation coefficients were found between RS and biomass of C. utilis. The coefficients of correlation increased as the TN level in hydrolysates was increased. PMID:16346708

  12. Effects of Some Environmental Factors on Growth Characteristics of Candida utilis on Peat Hydrolysates

    PubMed Central

    Chang, Fu-Hsian

    1985-01-01

    Samples of peat from Pine Island and Brookston bogs in Minnesota were hydrolyzed with various concentrations of HCl or H2SO4 solutions, before or after debituminization (an extraction process used to remove waxy materials, bitumens, from peat), to produce peak hydrolysates as growth substrates for Candida utilis. Hydrolysates were neutralized with concentrated NaOH solution to pH 3.5, 4.5, 5.0, 5.5, 6.0, and 7.0. The precipitated humates were removed by filtration. The resulting peat hydrolysates were amended with reagent-grade K2HPO4, K2SO4, and MgSO4, 200, 100, and 50 mg per liter of peat hydrolysate, respectively. The debituminized peat produced more total nitrogen (TN) and reducing substances (RS) than the nondebituminized peat. Peat hydrolysates produced by HCl solutions contained slightly higher RS and TN than those produced by H2SO4 solutions; however, the latter were better growth substrates than the former. The yield coefficients in both H2SO4 and HCl hydrolysates initially decreased at 12 to 24 h and then increased gradually over the remaining incubation period (24 to 96 h). As TN and RS were increased, an increase in cell density, biomass, and productivity was observed. In contrast, a decrease in specific growth rate occurred as the RS and TN were increased. The generation time of C. utilis was affected by the concentrations of RS and TN. A peak substrate yield coefficient was found at pH 5.0 in HCl hydrolysates and at pH 6.0 to 6.5 in H2SO4 hydrolysates. Good linear correlation coefficients were found between RS and biomass of C. utilis. The coefficients of correlation increased as the TN level in hydrolysates was increased. PMID:16346708

  13. Lateral carbon fluxes and CO2 outgassing from a tropical peat-draining river

    NASA Astrophysics Data System (ADS)

    Müller, D.; Warneke, T.; Rixen, T.; Müller, M.; Jamahari, S.; Denis, N.; Mujahid, A.; Notholt, J.

    2015-10-01

    Tropical peatlands play an important role in the global carbon cycle due to their immense carbon storage capacity. However, pristine peat swamp forests are vanishing due to deforestation and peatland degradation, especially in Southeast Asia. CO2 emissions associated with this land use change might not only come from the peat soil directly but also from peat-draining rivers. So far, though, this has been mere speculation, since there has been no data from undisturbed reference sites. We present the first combined assessment of lateral organic carbon fluxes and CO2 outgassing from an undisturbed tropical peat-draining river. Two sampling campaigns were undertaken on the Maludam River in Sarawak, Malaysia. The river catchment is covered by protected peat swamp forest, offering a unique opportunity to study a peat-draining river in its natural state, without any influence from tributaries with different characteristics. The two campaigns yielded consistent results. Dissolved organic carbon (DOC) concentrations ranged between 3222 and 6218 μmol L-1 and accounted for more than 99 % of the total organic carbon (TOC). Radiocarbon dating revealed that the riverine DOC was of recent origin, suggesting that it derives from the top soil layers and surface runoff. We observed strong oxygen depletion, implying high rates of organic matter decomposition and consequently CO2 production. The measured median pCO2 was 7795 and 8400 μatm during the first and second campaign, respectively. Overall, we found that only 32 ± 19 % of the carbon was exported by CO2 evasion, while the rest was exported by discharge. CO2 outgassing seemed to be moderated by the short water residence time. Since most Southeast Asian peatlands are located at the coast, this is probably an important limiting factor for CO2 outgassing from most of its peat-draining rivers.

  14. Methane production and emission from peat. the influence of anions (sulphate, nitrate) from acid rain

    NASA Astrophysics Data System (ADS)

    Watson, Andrea; Nedwell, David B.

    The influence of sulphate concentrations on the production and emission of methane in two contrasting peat sites was determined. Seasonal changes in sulphate concentrations appeared to influence the amount of organic carbon oxidised to carbon dioxide by sulphate reduction at both peat sites. For the majority of the year at both sites the amount of carbon mineralised through sulphate reduction exceeded that being transformed to methane by methanogenic bacteria, except when sulphate reduction became sulphate limited. In order to sustain the high sulphate reduction rates measured in the peat sulphide formed from dissimilatory sulphate reduction must be reoxidised rapidly to sulphate within the peat. Laboratory experiments showed that addition of 500 μM sulphate and 100 μM nitrate to peat samples significantly inhibited methanogenesis. Sulphate appeared to be the more important inhibitor of methanogenesis since inhibition of methane formation occurred with additions of sulphate reflecting in situ concentrations. Supplements of either acetate and/or hydrogen in combination with molybdate to peat samples revealed that methanogenesis was hydrogen limited and that the majority of active methanogens were hydrogen-utilising methanogens. Methanogenesis in peat samples appeared to be dependant on sulphate reducing bacteria for provision of substrates. Great Dun Fell, receiving the largest sulphate loading, had the lower rates of microbial activity (methane formation and sulphate reduction rates) than Ellergower, which received less than half the annual sulphate deposition of Great Dun Fell. This implied that some other factor—possibly organic matter lability, was limiting microbial rates of methane formation and sulphate reduction at Great Dun Fell.

  15. Comparative performance of extraction strategies for polycyclic aromatic hydrocarbons in peats.

    PubMed

    Rey-Salgueiro, Ledicia; Pontevedra-Pombal, Xabier; Alvarez-Casas, Marta; Martínez-Carballo, Elena; García-Falcón, Mercedes Sonia; Simal-Gándara, Jesús

    2009-07-01

    The assessment of historical trends in atmospheric deposition of organic contaminants by using peat samples has been reported on several occasions because these samples represent an almost ideal medium for recording temporal changes in organic contaminant deposition rates. The determination of polycyclic aromatic hydrocarbons (PAHs) in peat samples is complicated due to the high content of organic matter in peat, which affects both extraction efficiency and analytical quality. A rapid and simple method is proposed for the determination of 10 US Environmental Protection Agency indicator PAHs in complex matrices such as peat. This article reviews and addresses the most relevant analytical methods for determining PAHs in peat. We discuss and critically evaluate three different extraction procedures, such as ultrasound-assisted solvent extraction (UASE), shaking and pressurized liquid extraction (PLE). Clean-up of extracts was performed by solid-phase extraction using silica cartridges. Detection of the selected PAHs was carried out by high-performance liquid chromatography coupled with fluorescence detection for determination. Optimization of the variables affecting extraction by the selected extraction techniques was conducted, concluding that the UASE extraction method using hexane:dichloromethane (80:20) as extractant was robust enough to determine the selected PAHs in peat samples with estimated quantification limits between 0.050 and 3.5 microg/kg depending on the PAH. UASE did not demand sophisticated equipment and long extraction times. PLE involved sophisticated equipment and showed important variations in the results. The method proposed was applied to the determination of PAHs in peat samples from Xistral Mountains (Galicia, Spain). PMID:19481756

  16. Determining the degree of peat decomposition - A comparison of different methods

    NASA Astrophysics Data System (ADS)

    Biester, Harald; Knorr, Klaus-Holger; Schellekens, Judith; Basler, Anna; Hermanns, Yvonne-Marie

    2014-05-01

    Peat humification or decomposition is a frequently used proxy to extract past time changes in hydrology and climate from peat bogs. During the past century several methods to determine changes in peat decomposition have been introduced. Most of these methods are operationally defined only and the chemical changes underlying the decomposition process are often poorly understood and lack validation. Due to the chemically undefined nature of many humification analyses the comparison of results obtained by different methods is difficult if not misleading. In this study we compared changes in peat decomposition in cores of two peat bogs (Königsmoor (KK), Kleines Rotes Bruch (KRB)) from the Harz Mountains (Germany) using C/N ratios, Fourier Transform Infrared spectra absorption (FTIR) intensities, Rock Eval® oxygen- and hydrogen indices, δ13C and δ15N isotopic signatures and UV-absorption of NaOH peat extracts. In addition, one of the cores was analysed for changes in the peat's molecular composition using pyrolysis gas chromatography mass spectrometry (pyrolysis-GC-MS). Records of decomposition proxies show similar historical development at both sites, indicating external forcing such as climate as controlling process. Moreover, all decomposition proxies except UV-ABS and δ15N isotopes show similar patterns in their records and thus reflect in different extents signals of decomposition. Pyrolysis-GC-MS analyses of the KK core reveal that changes in peat molecular chemistry are mainly attributed to decomposition processes and to a lesser extend to changes in vegetation. Changes in the abundance of molecular compounds indicate that peat decomposition in the KK bog is mainly characterized by preferential decomposition of phenols and polysaccharides and relative enrichment of aliphatics during drier periods. Enrichment of lignin and other aromatics during decomposition was also observed but showed less variation, and presumably reflects changes in vegetation associated

  17. 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

  18. 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

  19. Dynamics of organic carbon stock of Estonian arable and grassland peat soils

    NASA Astrophysics Data System (ADS)

    Kauer, Karin; Tammik, Kerttu; Penu, Priit

    2016-04-01

    Peat soils represent globally a major reserve of soil organic carbon (SOC). Estimation of changes in SOC stocks is important for understanding soil carbon sequestration and dynamics of greenhouse gas emissions. The aim of this study was to estimate the SOC stock of Estonian agricultural peat soils and SOC stock change depending on land use type (arable land and long-term grasslands (over 5 years)). The soils were classified as Histosols according to WRB classification. Generally the arable land was used for growing cereals, oilseed rape, legumes and used as ley in crop rotation. The main technique of soil cultivation was ploughing. During 2002-2015 the soil samples of 0-20 cm soil layer (one average soil sample per 1-5 ha) were collected. The SOC content was measured by NIRS method. The SOC stock was calculated by assuming that soil mean bulk density is 0.3 g cm-3. The SOC stock change in arable land was estimated during 3-13 years (N=91) and in grassland 4-13 year (N=163). The average SOC content of peat soils varied from 150.6 to 549.0 mg g-1. The initial SOC stock of arable land was 271.3 t ha-1 and of grassland 269.3 t ha-1. The SOC stock declined in arable peat soils faster (-2.57 t ha-1 y-1) compared to the changes in grassland peat soils (-0.67 t ha-1 y-1). According to the length of the study period the SOC stock change per year varied from -5.14 to 6.64 t ha-1 y-1 in grasslands and from -14.78 to 0.83 t ha-1 y-1 in arable land, although there was no clear relationship between the SOC stock change and the length of the study period. More detailed information about the properties of agricultural land and land use history is needed to analyse the causes of the SOC stock changes in agricultural peat soils. However, from the current research we can conclude that the SOC stock of arable and grassland peat soils is declining during the cultivation. These decreases are important to specify when considering the role of peat soils in atmospheric greenhouse gas

  20. Imaging tropical peatlands in Indonesia using ground-penetrating radar (GPR) and electrical resistivity imaging (ERI): implications for carbon stock estimates and peat soil characterization

    NASA Astrophysics Data System (ADS)

    Comas, X.; Terry, N.; Slater, L.; Warren, M.; Kolka, R.; Kristiyono, A.; Sudiana, N.; Nurjaman, D.; Darusman, T.

    2015-05-01

    Current estimates of carbon (C) storage in peatland systems worldwide indicate that tropical peatlands comprise about 15% of the global peat carbon pool. Such estimates are uncertain due to data gaps regarding organic peat soil thickness, volume and C content. We combined a set of indirect geophysical methods (ground-penetrating radar, GPR, and electrical resistivity imaging, ERI) with direct observations using core sampling and C analysis to determine how geophysical imaging may enhance traditional coring methods for estimating peat thickness and C storage in a tropical peatland system in West Kalimantan, Indonesia. Both GPR and ERI methods demonstrated their capability to estimate peat thickness in tropical peat soils at a spatial resolution not feasible with traditional coring methods. GPR is able to capture peat thickness variability at centimeter-scale vertical resolution, although peat thickness determination was difficult for peat columns exceeding 5 m in the areas studied, due to signal attenuation associated with thick clay-rich transitional horizons at the peat-mineral soil interface. ERI methods were more successful for imaging deeper peatlands with thick organomineral layers between peat and underlying mineral soil. Results obtained using GPR methods indicate less than 3% variation in peat thickness (when compared to coring methods) over low peat-mineral soil interface gradients (i.e., below 0.02°) and show substantial impacts in C storage estimates (i.e., up to 37 MgC ha-1 even for transects showing a difference between GPR and coring estimates of 0.07 m in average peat thickness). The geophysical data also provide information on peat matrix attributes such as thickness of organomineral horizons between peat and underlying substrate, the presence of buried wood, buttressed trees or tip-up pools and soil type. The use of GPR and ERI methods to image peat profiles at high resolution can be used to further constrain quantification of peat C pools and

  1. Geoinformatics meets education for a peat bog information system

    NASA Astrophysics Data System (ADS)

    Michel, Ulrich; Fiene, Christina; Plass, Christian

    2010-10-01

    Within the project "Expedition Bog: Young researchers are experimenting, exploring and discovering" a bog-information- system is developed by the Department of Geography (University of Education Heidelberg, Germany), the Institute for Geoinformatics and Remote Sensing (University of Osnabrueck, Germany; the NABU Umweltpyramide gGmbH. This information system will be available for schools and to the public. It is supplemented by teaching units on various topics around the bog via an online platform. The focus of the project, however, is the original encounter with the bog habitat. This is realized by a GPS scavenger hunt with small research tasks and observations, mapping and experiments. The project areas are the Huvenhoops bog and the Lauenbruecker bog in Rotenburg in Lower Saxony, Germany. Equipped with a researcher backpack, GPS device and a mobile bog book by means of a pocket PC, students can discover different learning stations in the project bogs. In our areas the students can learn more about different topics such as "the historical memory of the bog", "water", "peat moss and other plants" and "animals of the bog". Moreover small inquiry research projects can be executed. Experimenting on site helps students to develop important scientific findings and increases their curiosity and enthusiasm for nature. It also promotes a number of other basic skills such as literacy, language skills, social skills or fine motor skills. Moreover it also fosters the development of a positive attitude to science in general. The main objective of the project is to promote sustainable environmental education, as well as the development of environmental awareness. This will be accomplished through the imparting of knowledge but also through experiencing nature with all senses in the context of original encounters.

  2. Water Table Dynamics of a Canadian Rocky Mountain Peat Floodplain

    NASA Astrophysics Data System (ADS)

    Westbrook, C. J.

    2008-12-01

    Floodplains of broad mountain valleys serve as collection points for local precipitation, hillslope runoff, deeper groundwater, and channel water. Little is known about how complex hydrological interactions among these water sources govern floodplain water table dynamics, particularly on an event basis partly owing to a lack of high frequency spatial and temporal data. Here I describe the magnitude and rate of change of groundwater storage in a Canadian Rocky Mountain peat floodplain. Weekly manual measurement of groundwater levels in a network of 51 water table wells during the summers of 2006 and 2007 showed large temporal and spatial variations in well response. Cluster analysis and principle components analysis were performed on these data to objectively classify the floodplain into spatial response units. Results were classification of the standpipes into five distinct water table regimes. One well representing each water table regime was outfitted with a sensor in 2008 that collected hourly head, which was used to characterize temporal patterns of water table response. Preliminary results indicate a constant increase in heterogeneity in the spatial pattern of the water table as the floodplain dried. In spring, snowmelt runoff combined with an ice lens 20-30 cm below the ground surface led to consistently high water tables throughout the floodplain. Water table regime responses to rain events during this period were flashy, with dramatic rises and falls (up to 20 cm) in short periods of time (<30 h), suggesting the unsaturated zone was close to saturation. In summer, the water table fell throughout the floodplain in response to declining hillslope inputs and increased evaporative demand, but rates of decline were highly variable among the water table regimes. This variability reflects differences in the degree to which the water table regimes are influenced by stream stage, hillslope inputs, and proximity to beaver dams. Results from this study have

  3. Peat biogasification development program. Quarterly progress report No. 2, January 1-March 31, 1980

    SciTech Connect

    Wise, Donald L.; Buivid, Michael G.

    1980-01-01

    Batch experiments have been performed to determine the effects of different alkalis, temperatures, retention times, solids loading, and oxygen partial pressures on the solubility of peat organic material. Oxidation experiments have been performed simultaneously with and separately from solubilization. In both cases kinetic information has been developed based on oxygen consumption. Kinetics based on fermentable product formation are dependent on satisfactory identification methods. Development of analytical procedures for product identification have included: Gel Permeation Chromatography (GPC), solvent extraction, aldehyde precipitation, and Thin Layer Chromatography (TLC). Microorganisms from three inoculation sources are being grown anaerobically using a growth medium containing a standard nutrient and a specific substrate, one of twelve aromatic compounds. The concentration of aromatic compound was increased gradually in order that bacteria acclimate for future use as inocula with pretreated peat liquors. Acids and methane production are being monitored for pretreated peat liquor fermentations using an acclimated microorganism inocula. Apparent viscosity and apparent heat transfer coefficient data are being obtained at three peat slurry solids concentrations (3-5, 10, 15% total solids). A 75% heat recovery would give a positive energy balance around the pretreatment reactor. Development has continued in regards to full scale peat biogasification design (75 x 10/sup 6/ SCFD, pipeline quality methane). The information necessary for continuous PDU scale operation is being evaluated in terms of what processing information may be obtained from various scale units, batch and continuous.

  4. Inorganic Horizon Development and Metal Concentrations in a Peat Deposit in Congaree National Park, SC

    NASA Astrophysics Data System (ADS)

    Werts, S. P.; Wesselschmidt, N.

    2012-12-01

    Congaree National Park, near Columbia, South Carolina, is a closed canopy floodplain forest that contains one of the United States' largest contiguous track of old-growth bottomland forest. A portion of the park contains a groundwater fed muckswamp and is in the footprint of several ancient meanders of the Congaree River. Within one ancient meander lies an extensive peat deposit that is in itself 3.5 meters thick. Within the top 20 cm of this peat, however, an inorganic horizon has developed and varies in thickness laterally throughout the deposit. Through the use of particle size analysis, δ13C and δ15N data and heavy metal concentrations as determined by ICP-CID, we propose that this inorganic horizon has developed from association with vertical translocation of soil material from the upper portions of the peat to the layers below. This can be seen through the accumulation of clays in the lower portions of the inorganic layer and the accumulation of heavy metals in the peat just below the inorganic layer. We believe that this is occurring as an artifact of large seasonal changes in the water table in this portion of the park as plant productivity and drawdown is high in the spring and summer followed by a rise in the water table in the winter, as seen through local piezometer data. This removal of organic material from the upper peat deposits will have implications of water quality and the local carbon cycle associated with the park and the Congaree River.

  5. 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

  6. New approaches to estimation of peat deposits for production of biologically active compounds

    NASA Astrophysics Data System (ADS)

    Stepchenko, L. M.; Yurchenko, V. I.; Krasnik, V. G.; Syedykh, N. J.

    2009-04-01

    It is known, that biologically active preparations from peat increase animals productivity as well as resistance against stress-factors and have adaptogeneous, antioxidant, immunomodulative properties. Optymal choice of peat deposits for the production of biologically active preparations supposes the detailed comparative analysis of peat properties from different deposits. For this the cadastre of peat of Ukraine is developed in the humic substances laboratory named after prof. Khristeva L.A. (Dnipropetrovsk Agrarian University, Ukraine). It based on the research of its physical and chemical properties, toxicity and biological activity, and called Biocadastre. The Biocadastre is based on the set of parameters, including the descriptions of physical and chemical properties (active acidity, degree of decomposition, botanical composition etc.), toxicity estimation (by parabyotyc, infusorial, inhibitor and other tests), biological activity indexes (growth-promoting, antioxidative, adaptogeneous, immunomodulative antistress and other actions). The blocks of Biocadastre indexes are differentiated, taking into account their use for creation the preparations for vegetable, animals and microorganisms. The Biocadastre will allow to choose the peat deposits, most suitable for the production of different biologically active preparations, both wide directed and narrow spectrum of action, depending on application fields (medicine, agriculture, veterinary medicine, microbiological industry, balneology, cosmetology).

  7. Development of new peat based growing media by addition of pruning waste and biochars

    NASA Astrophysics Data System (ADS)

    Nieto, Aurora; Gascó, Gabriel; Paz-Ferreiro, Jorge; Plaza, César; Fernández, José Manuel; Méndez, Ana

    2015-04-01

    In the last years, several researches have been performed to find high quality and low cost substrates from different organic wastes in order to decrease peat consumption since the indiscriminate exploitation of peat lands is exhausting this non-renewable useful resource and destroying endangered wetland ecosystems worldwide. The use of organic wastes as soil amendments or possible peat substitute could be improved by pyrolysis treatment, leading to biochar, a carbon-rich material that has attached important attention. Our research group has been worked in the formulation of new based-growing media by peat substitution in 50 and 75 vol% of pruning waste (PW), commercial charcoal (CC), biochar from PW at 300°C (B300) and 500°C (B500). Growing media show adequate physicochemical and hydrophysical properties. Experiments performed with lettuce germination show that PW addition in a 75vol% reduces germination index probably due to their high content on phenolic compounds. Lettuce growing experiments were performed during 5 weeks and show that addition of PW and CC to peat decreases biomass production whereas; B300 and specially, B500 addition significantly increases the lettuce biomass.

  8. 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.

  9. Hyperspectral data application for peat forest monitoring in Central Kalimantan, Indonesia

    NASA Astrophysics Data System (ADS)

    Ohki, Takashi; Yoshida, Keigo; Sekine, Hozuma; Takayama, Taichi; Takeda, Tomomi; Hirose, Kazuyo; Evri, Muhammad; Osaki, Mitsuru

    2012-11-01

    Peatland is a large CO2 reservoir which accumulates 2000Gt of CO2, which is equal to 30% of global soil carbon. However, it has been becoming a large CO2 emission source because of peat decomposition and fire due to drainage water. This is caused by social activities such as canalizing. Especially, in Indonesia, peat swamp forests cover considerable portions of Kalimantan and 37.5% of CO2 emission source is peatland (DNPI, 2010). To take measures, it is necessary to conduct appropriate assessment of CO2 emission in broad peat swamp forest. Because hyperspectral data possess higher spectral resolutions, it is expected to evaluate the detailed forest conditions. We develop a method to assess carbon emission from peat swamp forest by using hyperspectral data in Central Kalimantan, Indonesia. Specifically, we estimate 1) forestry biomass and 2) underground water level expected as an indicator of CO2 emission from peat. In this research, we use the image taken by HyMAP which is one of the airborne hyperspectral sensors. Since the research area differs in forest types and conditions due to the past forest fire and disturbance, forest types are classified with the sparse linear discriminant analysis. Then, we conduct a biomass estimation using Normalized Difference Spectral Index (NDSI). We also analyze the relationship between underground water level and Normalized Difference Water Index (NDWI), and find the possibility of underground water level estimation with hyperspectral data. We plan to establish a highly developed method to apply hyperspectral sensor to peatland monitoring system.

  10. Catalytic pyrolysis of peat with additions of oil-slime and polymeric waste

    NASA Astrophysics Data System (ADS)

    Sulman, E.; Kosivtsov, Yu.; Sulman, M.; Alfyorov, V.; Lugovoy, Yu.; Chalov, K.; Misnikov, O.; Afanasjev, A.; Kumar, N.; Murzin, D.

    2012-09-01

    In this work the influence of natural and synthetic aluminosilicates, metal chlorides of iron subgroup on the peat low-temperature pyrolysis and co-pyrolysis of peat with oil-slime and polymeric waste was studied in variety of conditions (t = 350-650δC, catalyst loading: from 1 up to 30 % (wt.)). The use of bentonite clay (30 % (wt.)) at 460δC as a catalyst in peat pyrolysis resulted in increase of weight of gaseous and liquid products from 23 up to 30 % (wt.) and from 32 up to 45 % (wt.), respectively. Co-pyrolysis of peat and oil-slime in the presence of bentonite clay resulted in increase of gaseous product weight from 18 up to 26 % (wt.) and liquid fraction yield - from 45 up to 55 % (wt.) in comparison with precalculated value. The use of metal chlorides of iron subgroup (2 % (wt.) concentration) at 500 δC in the co-pyrolysis of peat and polymeric waste led to optimal conversion of substrate in desired products, 15 % increase of total weight of gaseous and liquid products formed during the pyrolysis process and simultaneous decrease of char formation.

  11. Seasonal and inter-annual variation in the chlorophyll content of three co-existing Sphagnum species exceeds the effect of solar UV reduction in a subarctic peatland.

    PubMed

    Hyyryläinen, Anna; Rautio, Pasi; Turunen, Minna; Huttunen, Satu

    2015-01-01

    We measured chlorophyll (chl) concentration and chl a/b ratio in Sphagnum balticum, S. jensenii, and S. lindbergii, sampled after 7 and 8 years of ultraviolet-B (UVB) and temperature manipulation in an open field experiment in Finnish Lapland (68°N). We used plastic filters with different transmittance of UVB radiation to manipulate the environmental conditions. The plants were exposed to (1) attenuated UVB and increased temperature, (2) ambient UVB and increased temperature and (3) ambient conditions. Chlorophyll was extracted from the capitula of the mosses and the content and a/b ratio were measured spectrophotometrically. Seasonal variation of chlorophyll concentration in the mosses was species specific. Temperature increase to 0.5-1 °C and/or attenuation of solar UVB radiation to ca. one fifth of the ambient (on average 12 vs. 59 uW/cm(2)) had little effect on the chlorophyll concentration or its seasonal variation. In the dominant S. lindbergii, UVB attenuation under increased temperature led to a transient decrease in chlorophyll concentration. Altogether, species-specific patterns of seasonal chlorophyll variation in the studied Sphagna were more pronounced than temperature and UVB treatment effects. PMID:26361579

  12. Modelling and mapping trace element accumulation in Sphagnum peatlands at the European scale using a geomatic model of pollutant emissions dispersion.

    PubMed

    Diaz-de-Quijano, Maria; Joly, Daniel; Gilbert, Daniel; Toussaint, Marie-Laure; Franchi, Marielle; Fallot, Jean-Michel; Bernard, Nadine

    2016-07-01

    Trace elements (TEs) transported by atmospheric fluxes can negatively impact isolated ecosystems. Modelling based on moss-borne TE accumulation makes tracking TE deposition in remote areas without monitoring stations possible. Using a single moss species from ombrotrophic hummock peatlands reinforces estimate quality. This study used a validated geomatic model of particulate matter dispersion to identify the origin of Cd, Zn, Pb and Cu accumulated in Sphagnum capillifolium and the distance transported from their emission sources. The residential and industrial sectors of particulate matter emissions showed the highest correlations with the TEs accumulated in S. capillifolium (0.28(Zn)-0.56(Cu)) and (0.27(Zn)-0.47(Cu), respectively). Distances of dispersion varied depending on the sector of emissions and the considered TE. The greatest transportation distances for mean emissions values were found in the industrial (10.6 km when correlating with all TEs) and roads sectors (13 km when correlating with Pb). The residential sector showed the shortest distances (3.6 km when correlating with Cu, Cd, and Zn). The model presented here is a new tool for evaluating the efficacy of air pollution abatement policies in non-monitored areas and provides high-resolution (200 × 200 m) maps of TE accumulation that make it possible to survey the potential impacts of TEs on isolated ecosystems. PMID:27061470

  13. Rates and Controls of N2 Fixation in Sphagnum spp. along the Hydrological Gradient - Beaver Pond to Bog Transition at Mer Bleue, Ontario, Canada

    NASA Astrophysics Data System (ADS)

    Zivkovic, T.; Moore, T. R.

    2014-12-01

    Many northern bogs with low atmospheric N inputs acquire N only via N2-fixation. Little is known about rates and controls on N2-fixation in bogs. The aim of this study was to: 1) test the important ecological drivers for N2-fixation, 2) investigate seasonal and temporal patterns of N2 fixation, and 3) to estimate current N2-fixation rates at Mer Bleue bog. We used acetylene reduction assay (ARA) to measure N2-fixation from June-October 2013 and 2014 (currently ongoing field season) along a hydrological gradient (beaver pond, hollows and hummocks). The highest ARA rates in 2013 growing season occurred in the pond in floating Sphagnum cuspidatum mats (50.3 ± 12.9 μmol m-2 d-1 Mean ± Std Err) which were up to 2.5 times latger than the rates found in the hummock with the lowest water table depth throughout the season. Two rain events during the summer 2013 increased ARA rates in all plots by 1 to 4 times, suggesting that moisture availability may play a crucial role on N2 fixation potential in the field. We are currently investigating the role of moisture, temperature, PAR and nutrient content (N, phosphorous and metals) on ARA along the gradient. In addition, we are using 15N2 enrichment method to estimate N2 fixation rates and compare them to ARA method at Mer Bleue bog.

  14. Peat-resource estimation in New York State. First quarterly report, 1 April 1981-30 June 1981

    SciTech Connect

    Peterson, J.M.

    1981-07-01

    This report discusses the progress made on the New York State peat inventory as of July 25, 1981. Achievements and results in the following areas are reported: collection of data; identification of protected land; standardization of mapping methods; index of all peat bogs; airphoto interpretation; drafting of maps; field crew mobilization; engineering time used; and problems incurred. (DMC)

  15. Climate and peat type in relation to spatial variation of the peatland carbon mass in the Hudson Bay Lowlands, Canada

    NASA Astrophysics Data System (ADS)

    Packalen, Maara S.; Finkelstein, Sarah A.; McLaughlin, James W.

    2016-04-01

    Northern peatlands store ~500 Pg of carbon (C); however, controls on the spatial distribution of the stored C may differ regionally, owing to the complex interaction among climate, ecosystem processes, and geophysical controls. As a globally significant C sink, elucidation of controls on the distribution of C in the Hudson Bay Lowlands, Canada (HBL), is of particular importance. Although peat age is related to timing of land emergence and peat depth in the HBL, considerable variation in the total C mass (kg m-2) among sites of similar peat age suggests that other factors may explain spatial patterns in C storage (Pg) and sequestration. Here we quantify the role of two key factors in explaining the spatial distribution of the C mass in the HBL (n = 364 sites), (i) climate variability and (ii) peat lithology, for two major peatland classes in the HBL (bogs and fens). We find that temperature, precipitation, and evapotranspiration each explained nearly half of the C mass variability. Regions characterized by warmer and wetter conditions stored the most C as peat. Our results show that bogs and fens store similar amounts of C within a given climate domain, although via distinct storage mechanisms. Namely, fen peats tend to be shallower and more C dense (kg m-3) compared to bogs. Following geophysical controls on the timing of peat initiation, our results reveal that both the widespread bog-fen patterning and variability in regional climate contribute to explaining the spatial distribution of the peat C mass in the HBL.

  16. Exploitation of peat geochemistry to reconstruct hydrological and biogeochemical variations during the late Holocene

    NASA Astrophysics Data System (ADS)

    McClymont, E. L.; Bingham, E.; Charman, D.; Chambers, F.; Pancost, R. D.; Evershed, R. P.; Accrotelm Members

    2011-12-01

    Peatlands are valuable terrestrial archives of past climatic change, recording past variations in local (mire) hydrology and vegetation, alongside evidence for regional landscape change. The decadal to centennial resolution of peat cores makes the climatic and environmental signals that they contain of relevance to understanding human/environment interactions. Records of ombrotrophic mires are of particular value, as the depth of the water table reflects the balance between precipitation and evaporation (effective precipitation), and is thus closely linked to the regional climate. A variety of proxies have been applied to peats that record either the biological or redox response to changing mire conditions, including macrofossils, testate amoebae, and changes to bulk geochemistry. The last of these reflects the different decomposition processes that affect organic matter in response to the presence or absence of oxygen in the upper layers of the peat, which is driven by varying water table depth. However, bulk geochemistry of peat is also affected by the dominant plant inputs to the peat profile, which can also evolve through time and limit the isolation of a hydrological signal. Here, we show some promising new organic geochemistry proxies that can be applied to peats to understand both changing hydrology and the biogeochemical impacts that result. For example, the biomarker archaeol is argued to reflect methanogen activity below the water table. We also exploit the degradation of plant sterols under oxic conditions to identify times when the water table was low. In exploring a suite of mires, distributed from Ireland to Finland, we compare the environmental controls on these proxies. Furthermore, we apply this knowledge to examine the regional European expression of a key event in the late Holocene, the Sub-boreal / Sub-atlantic transition at 2.8 ka.

  17. Peat formation concentrates arsenic within sediment deposits of the Mekong Delta

    NASA Astrophysics Data System (ADS)

    Stuckey, Jason W.; Schaefer, Michael V.; Kocar, Benjamin D.; Dittmar, Jessica; Pacheco, Juan Lezama; Benner, Shawn G.; Fendorf, Scott

    2015-01-01

    Mekong River Delta sediment bears arsenic that has been released to groundwater under anaerobic conditions over the past several thousand years. The oxidation state, speciation, and distribution of arsenic and the associated iron bearing phases are crucial determinants of As reactivity in sediments. Peat from buried mangrove swamps in particular may be an important host, source, or sink of arsenic in the Mekong Delta. The total concentration, speciation, and reactivity of arsenic and iron were examined in sediments in a Mekong Delta wetland by X-ray fluorescence spectrometry (XRF), X-ray absorption spectroscopy (XAS), and selective chemical extractions. Total solid-phase arsenic concentrations in a peat layer at a depth of 6 m below ground increased 10-fold relative to the overlying sediment. Extended X-ray absorption fine structure (EXAFS) spectroscopy revealed that arsenic in the peat was predominantly in the form of arsenian pyrite. Arsenic speciation in the peat was examined further at the micron-scale using μXRF and μX-ray absorption near-edge structure (XANES) spectroscopy coupled with principal component analysis. The multiple energy μXRF mapping and μXANES routine was repeated for both iron and sulfur phase analyses. Our μXRF/μXANES analyses confirm arsenic association with pyrite - a less reactive host phase than iron (hydr)oxides under anaerobic conditions. The arsenian pyrite likely formed upon deposition/formation of the peat in a past estuarine environment (∼5.5 ka BP), a process that is not expected under current geochemical conditions. Presently, arsenian pyrite is neither a detectable source nor a sink for aqueous arsenic in our sediment profile, and under present geochemical conditions represents a stable host of As under the reducing aquifer conditions of the Mekong Delta. Furthermore, organic carbon within the peat is unable to fuel Fe(III) reduction, as noted by the persistence of goethite which can be reduced microbially with the

  18. Rhizosphere impacts on peat decomposition and nutrient cycling across a natural water table gradient

    NASA Astrophysics Data System (ADS)

    Gill, A. L.; Finzi, A.

    2014-12-01

    High latitude forest and peatland soils represent a major terrestrial carbon store sensitive to climate change. Warming temperatures and increased growing-season evapotranspiration are projected to reduce water table (WT) height in continental peatlands. WT reduction increases peat aerobicity and facilitates vascular plant and root growth. Root-associated microbial communities are exposed to a different physical and chemical environment than microbial communities in non-root associated "bulk" peat, and therefore have distinct composition and function within the soil system. As the size of the peatland rhizosphere impacts resources available to the microbial communities, transitions from a root-free high water table peatland to a root-dominated low WT peatland may alter seasonal patterns of microbial community dynamics, enzyme production, and carbon storage within the system. We used a natural water table gradient in Caribou Bog near Orono, ME to explore the influence of species composition, root biomass, and rhizosphere size on seasonal patterns in microbial community structure, enzyme production, and carbon mineralization. We quantified root biomass across the water table gradient and measured microbial biomass carbon and nitrogen, C mineralization, N mineralization, and exoenzyme activity in root-associated and bulk peat samples throughout the 2013 growing season. Microbial biomass was consistently higher in rhizosphere-associated soils and peaked in the spring. Microbial biomass CN and enzyme activity was higher in rhizosphere-associated soil, likely due to increased mycorrhizal abundance. Exoenzyme activity peaked in the fall, with a larger relative increase in enzyme activity in rhizosphere peat, while carbon mineralization rates did not demonstrate a strong seasonal pattern. The results suggest that rhizosphere-associated peat sustains higher and more variable rates of enzyme activity throughout the growing season, which results in higher rates of carbon

  19. 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

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

    PubMed

    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