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Sample records for upland peat soils

  1. Peat soils as a source of lead contamination to upland fluvial systems.

    PubMed

    Rothwell, James J; Evans, Martin G; Daniels, Stephen M; Allott, Timothy E H

    2008-06-01

    Upland peat soils are generally regarded as effective sinks of atmospherically deposited lead. However, the physical process of erosion has the potential to transform peat soils from sinks to sources of lead contamination. Lead input and fluvial lead outputs (dissolved+particulate) were estimated for a contaminated and severely eroding peatland catchment in the southern Pennines, UK. Lead input to the catchment is 30.0+/-6.0gha(-1)a(-1) and the output from the catchment is 317+/-22.4gha(-1)a(-1). Suspended particulate matter accounts for 85% of lead export. Contaminated peat soils of the catchment are a significant source of lead to the fluvial system. This study has demonstrated strong coupling between the physical process of erosion and the mobilization of lead into the fluvial system. The process of peat erosion should therefore be considered when estimating lead outputs from peatland catchments, especially in the context of climate change. PMID:17949867

  2. Land management as a factor controlling dissolved organic carbon release from upland peat soils 1: spatial variation in DOC productivity.

    PubMed

    Yallop, A R; Clutterbuck, B

    2009-06-01

    The importance of soil storage in global carbon cycling is well recognised and factors leading to increased losses from this pool may act as a positive feedback mechanism in global warming. Upland peat soils are usually assumed to serve as carbon sinks, there is however increasing evidence of carbon loss from upland peat soils, and DOC concentrations in UK rivers have increased markedly over the past three decades. A number of drivers for increasing DOC release from peat soils have been proposed although many of these would not explain fine-scale variations in DOC release observed in many catchments. We examined the effect of land use and management on DOC production in upland peat catchments at two spatial scales within the UK. DOC concentration was measured in streams draining 50 small-scale catchments (b3 km2) in three discrete regions of the south Pennines and one area in the North Yorkshire Moors. Annual mean DOC concentration was also derived from water colour data recorded at water treatment works for seven larger scale catchments (1.5-20 km2) in the south Pennines. Soil type and land use/management in all catchments were characterised from NSRI digital soil data and ortho-corrected colour aerial imagery. Of the factors assessed, representing all combinations of soil type and land use together with catchment slope and area, the proportion of exposed peat surface resulting from new heather burning was consistently identified as the most significant predictor of variation in DOC concentration. This relationship held across all blanket peat catchments and scales. We propose that management activities are driving changes in edaphic conditions in upland peat to those more favourable for aerobic microbial activity and thus enhance peat decomposition leading to increased losses of carbon from these environments. PMID:19345986

  3. The effects of burning and sheep-grazing on water table depth and soil water quality in a upland peat

    NASA Astrophysics Data System (ADS)

    Worrall, F.; Armstrong, A.; Adamson, J. K.

    2007-06-01

    SummaryRotational burning of heather to improve grazing and grouse breeding is a common management practice for upland catchments in the UK. However, the effects of such practices on hydrology and water quality are not well understood because the timescale of burning rotation is typically between 7 and 20 years thus requiring long-term experiments in order to resolve the effects. Furthermore, land management, such as changes in burning or grazing practices, has been proposed as a possible strategy for the remediation of the widespread increases in dissolved organic carbon (DOC) observed across the northern hemisphere. This study is based on a long-term experiment on the effect of different rotational burning cycles and grazing intensities on upland vegetation and aims to understand the effects of these management strategies on hydrology and water quality. The main outcomes are: The depth to water table in the soil showed significant differences between different burning rotations and grazing intensities. Depth to water table was greatest on plots where burning did not occur or for longer burning cycles where livestock had been excluded. The pH and conductivity of sampled soil water showed no significant difference between grazing treatments, with the presence of burning being the most important factor (frequency of the burning cycle was not important). The DOC content showed no significant difference between grazing treatments but showed a significant decrease with the presence of burning, though no direct relationship with the depth to water table could be found. Burn management explains only a small proportion of the variance in the composition of the DOC, rather the variation is dominated by the differences between days of sampling and seasonal variation. Therefore, this study suggests that land management controls hydrology and water quality through controlling the development of vegetation.

  4. Land management as a factor controlling dissolved organic carbon release from upland peat soils 2: changes in DOC productivity over four decades.

    PubMed

    Clutterbuck, B; Yallop, A R

    2010-11-15

    Increasing DOC concentrations in surface waters have been observed across parts of Europe and North America over the past few decades. Most proposed explanations for these widespread trends invoke climate change or reductions in sulphate deposition. However, these factors do not seem apposite to explain either the fine-scale (within kilometres) or regional-scale spatial variation in DOC concentrations observed across the UK. We have reconstructed DOC concentrations and land use for one North Pennine and five South Pennine catchments (UK), located in three discrete areas, over the last four decades. Rainfall, temperature and sulphate deposition data, where available, were also collated and the potential influence of these factors on surface water DOC concentrations was assessed. Four of the six catchments examined showed highly significant (p<0.001) increases (53-92%) in humic coloured DOC (hDOC) concentrations in drainage waters over the period 1990-2005. Changes in temperature and sulphate deposition may explain 20-30% of this trend in these four catchments. However, the rapid expansion of new moorland burn on blanket peat can explain a far greater degree (>80%) of the change in hDOC. Far smaller increases in hDOC (10-18%) were identified for the two remaining catchments. These two sites experienced similar changes in sulphur deposition and temperature to those that had seen largest increases in DOC, but contained little or no moorland burn management on blanket peat. This study shows that regional-scale factors undoubtedly underlie some of the recent observed increases in drainage humic coloured DOC. However, changes in land management, in this case the extensive use of fire management on blanket peat, are a far more important driver of increased hDOC release from upland catchments in some parts of the UK. It suggests that the recent rapid increase in the use of burning on blanket peat moorland has implications for ecosystem services and carbon budgets. PMID:20869100

  5. Soil zonality of the Chukotka Upland

    NASA Astrophysics Data System (ADS)

    Karavaeva, N. A.

    2013-05-01

    The vertical soil-geographic zonality of the Chukotka Upland in the area of the Amguema River valley can be considered a model vertical zonality in the Low Arctic regions at the interface between the continental and oceanic climates. The plain bottom of the valley has a continental climate. The surrounding mountains are under the influence of an oceanic climate, which is more pronounced in the low mountains and less pronounced in the medium-high mountains. Three altitudinal soil zones are distinguished: (1) the plain Subarctic zone with the absolute heights below 200-400 m a.s.l., where cryoturbated humus-impregnated peat-mucky gleyzems are developed from loamy substrates, and gleyed soddy podburs are developed from loamy sandy substrates; (2) the low-mountain zone of a creeping alder forest (the forest-tundra zone?) of the Low Arctic at the heights of 400-700 m a.s.l., where mucky-gray-humus humus-impregnated podzolized gleyzems are developed under tundra patches, cryoturbated peat-mucky high-humus-impregnated podzolized gleyzems are developed under creeping alder thickets, and pedoliths are exposed in the zones of landslides; and (3) the mountain Middle Arctic zone at elevations above 700 m a.s.l., where very thin soil films predominate; gray-humus cryometamorphic lithozems are developed from the eluvium of magmatic rocks, and humus-impregnated cryometamorphic soils with quicksand suprapermafrost horizons are developed from the eluvium of hard sedimentary rocks.

  6. Characterizing Pb mobilization from upland soils to streams using (206)Pb/(207)Pb isotopic ratios.

    PubMed

    Dawson, Julian J C; Tetzlaff, Doerthe; Carey, Anne-Marie; Raab, Andrea; Soulsby, Chris; Killham, Kenneth; Meharg, Andrew A

    2010-01-01

    Anthropogenically deposited lead (Pb) binds efficiently to soil organic matter, which can be mobilized through hydrologically mediated mechanisms, with implications for ecological and potable quality of receiving waters. Lead isotopic ((206)Pb/(207)Pb) ratios change down peat profiles as a consequence of long-term temporal variation in depositional sources, each with distinctive isotopic signatures. This study characterizes differential Pb transport mechanisms from deposition to streams at two small catchments with contrasting soil types in upland Wales, U.K., by determining Pb concentrations and (206)Pb/(207)Pb ratios from soil core profiles, interstitial pore waters, and stream water. Hydrological characteristics of soils are instrumental in determining the location in soil profiles of exported Pb and hence concentration and (206)Pb/(207)Pb ratios in surface waters. The highest Pb concentrations from near-surface soils are mobilized, concomitant with high dissolved organic carbon (DOC) exports, from hydrologically responsive peat soils with preferential shallow subsurface flows, leading to increased Pb concentrations in stream water and isotopic signatures more closely resembling recently deposited Pb. In more minerogenic soils, percolation of water allows Pb, bound to DOC, to be retained in mineral horizons and combined with other groundwater sources, resulting in Pb being transported from throughout the profile with a more geogenic isotopic signature. This study shows that (206)Pb/(207)Pb ratios can enhance our understanding of the provenances and transport mechanisms of Pb and potentially organic matter within upland soils. PMID:19954181

  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. Climate mitigation scenarios of drained peat soils

    NASA Astrophysics Data System (ADS)

    Kasimir Klemedtsson, Åsa; Coria, Jessica; He, Hongxing; Liu, Xiangping; Nordén, Anna

    2014-05-01

    The national inventory reports (NIR) submitted to the UNFCCC show Sweden - which as many other countries has wetlands where parts have been drained for agriculture and forestry purposes, - to annually emit 12 million tonnes carbon dioxide equivalents, which is more GHG'es than industrial energy use release in Sweden. Similar conditions can be found in other northern countries, having cool and wet conditions, naturally promoting peat accumulation, and where land use management over the last centuries have promoted draining activities. These drained peatland, though covering only 2% of the land area, have emissions corresponding to 20% of the total reported NIR emissions. This substantial emission contribution, however, is hidden within the Land Use Land Use Change and Forestry sector (LULUCF) where the forest Carbon uptake is even larger, which causes the peat soil emissions become invisible. The only drained soil emission accounted in the Swedish Kyoto reporting is the N2O emission from agricultural drained organic soils of the size 0.5 million tonnes CO2e yr-1. This lack of visibility has made incentives for land use change and management neither implemented nor suggested, however with large potential. Rewetting has the potential to decrease soil mineralization, why CO2 and N2O emissions are mitigated. However if the soil becomes very wet CH4 emission will increase together with hampered plant growth. By ecological modeling, using the CoupModel the climate change mitigation potential have been estimated for four different land use scenarios; 1, Drained peat soil with Spruce (business as usual scenario), 2, raised ground water level to 20 cm depth and Willow plantation, 3, raised ground water level to 10 cm depth and Reed Canary Grass, and 4, rewetting to an average water level in the soil surface with recolonizing wetland plants and mosses. We calculate the volume of biomass production per year, peat decomposition, N2O emission together with nitrate and DOC/POC leakage. Based on the modelling results a cost benefit analysis is performed (economics), guiding to the design of environmental policies needed for land use change to come true.

  9. 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.

  10. INFLUENCE OF REDOX ON THE RHIZOSPHERE CHEMISTRY OF UPLAND SOILS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many upland soils in the Midwest of the US are temporally flooded during the Spring. These soils can remain water saturated for days, weeks, or even months. The effects of prolonged saturation on the biogeochemical processes that occur in these soils are not fully understood and are the subject of...

  11. DOC export from an upland peat catchment in the Flow Country, northern Scotland

    NASA Astrophysics Data System (ADS)

    Vinjili, Shailaja; Robinson Robinson, Ruth; Arn Teh, Yit; Waldron, Susan; Singer, Michael

    2010-05-01

    Flow Country blanket bogs in northern Scotland are the most expansive in Europe covering an area of ~4000 km2, and they significantly impact the global carbon cycle because of their high rates of carbon production and storage, as well as their role in the transfer of carbon to oceans through rivers or greenhouse gas exchange (Moore et al., 1998). These upland areas are highly susceptible to climatic and landuse changes, and currently, large areas of previously drained and forested peatlands are being felled and blocked to increase the water table level and rejuvenate the peatlands (LIFE Peatlands Project 2001-2006; Holden et al., 2004). This study is examining the event-based export of dissolved and particulate organic carbon (DOC and POC) from one of the main upland Flow Country catchments that drains into the north-draining Halladale River. For a time-series of summer rainfall events, we have focussed particularly on a comparison of DOC/POC exports from three different land use areas in the catchment: forested plots, felled to waste (restoration) plots (felled between 2005-2007), and near-pristine bog sites. DOC concentrations have been measured using a combination of methods including TOC and EA analyses, and in situ absorbance measurements using a spectrophotometer (Thurman, 1985; Worrall et al., 2002). Our results show that the stream water draining the felled to waste site records the highest levels of DOC concentration (and DOC variability), and the near-pristine site has the lowest export rate of DOC (and lowest variability). All sites exhibit positive DOC responses to the flood hydrograph, and the near-pristine and forested sites have a similar maximum concentrations of DOC. The felled site concentrations are about 2times greater than the near-pristine and forested sites, and the non-linear response to flow reflects the hydrophobic nature of peats after a period of drought, and the lag time required for them to saturate. The integrated downstream DOC concentrations on forested land and on the main stem of the Halladale River have 'forest-like' values reflecting a dilution in DOC concentrations from the felled site, and mixing of stream water from other sources. The initial results from this study imply that i) the felled to waste site (after 2-3 years) releases the highest (up to x2) DOC into stream waters that drain them, ii) DOC concentrations are more sensitive to hydrological variation in sites felled to waste but not yet fully restored, and iii) saturation-excess overland flow is the predominant response of near-pristine site to the rainfall events. References: Holden J., Chapman P.J., and Labadz J.C. 2004. Artificial drainage of peatlands: hydrological and hydrochemical process and wetland restoration. Progress in Phy Geography, 28, 1, pp: 95-123. Life Peatlands Project 2001-2006. www.lifepeatlandsproject.com Moore T.R., Roulet N.T. and Waddington J.M. 1998. Uncertainty in Predicting the Effect of Climatic Change on the Carbon Cycling of Canadian Peatlands. Climate Change, 40, 2, pp: 229-245. Thurman E.M. 1985. Organic Geochemistry of Natural Waters. Netherlands, Martinus Nijhoff/Dr. W.Junk Publishers. Worrall F., Burt T. P., Jaeban R. Y., Warburton ,J. and R. Shedden, 2002. Release of dissolved organic carbon from upland peat. Hydrol. Process. 16, 3487-3504.

  12. 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.

  13. A 19-year long energy budget of an upland peat bog, northern England

    NASA Astrophysics Data System (ADS)

    Worrall, Fred; Clay, Gareth; Moody, Catherine; Burt, Timothy

    2015-04-01

    This study has estimated the long term evaporation record for a peat covered catchment in northern England. In this study, 19 years of daily evaporation were estimated for rain-free periods using White's methods. Net radiation was measured over the study period; soil heat flux was calculated from temperature profiles; and sensible heat flux was calculated assuming the energy budget was closed. The calculated time series was compared to available environmental information on the same time step and over the same time period. Over a 19-year period it was possible to calculate 1662 daily evaporation rates (26% of the period). The study showed that the energy flux to net primary productivity was a small, long-term sink of energy but this sink was a virtue of high carbon accumulation in peat catchments: in catchments where there is no long-term dry matter accumulation, net primary productivity must be a small net source of energy. The study showed that evaporation increased over the study period whilst sensible heat flux significantly declined with the ecosystem became a stronger heat sink reflecting an increased use of sensible heat energy to meet evaporative demand. The relatively small change in evaporative flux compared to other energy fluxes suggests that this system is a "near-equilibrium" system and not a "far-from-equilibrium" system.

  14. A 19-year long energy budget of an upland peat bog, northern England

    NASA Astrophysics Data System (ADS)

    Worrall, F.; Burt, T. P.; Clay, G. D.; Moody, C. S.

    2015-01-01

    This study has estimated the long term evaporation record for a peat covered catchment in northern England. In this study, 19 years of daily evaporation were estimated for rain-free periods using White's methods. Net radiation was measured over the study period; soil heat flux was calculated from temperature profiles; and sensible heat flux was calculated assuming the energy budget was closed. The calculated time series was compared to available environmental information on the same time step and over the same time period. Over a 19-year period it was possible to calculate 1662 daily evaporation rates (26% of the period). The study showed that the energy flux to net primry productivity was a small, long-term sink of energy but this sink was a virtue of high carbon accumulation in peat catchments: in catchments where there is no long-term dry matter accumulation, net primary productivity must be a small net source of energy. The study showed that evaporation increased over the study period whilst sensible heat flux significantly declined, reflecting an increased use of sensible heat energy to meet evaporative demand. The relatively small change in evaporative flux compared to other energy fluxes suggests that this system is a "near-equilibrium" system and not a "far-from-equilibrium" system.

  15. Transfer of technetium from soil to paddy and upland rice.

    PubMed

    Yanagisawa, K; Muramatsu, Y

    1995-09-01

    Soil-plant transfer factors (concentration ratio between the plant and soil) of technetium in paddy and upland rice plants were obtained from laboratory experiments. The transfer factor is one of the most important parameters for environmental radiation dose assessment. Technetim tracer (95mTcO4-) was added to the soil prior to rice cultivation. The transfer factor of technetium for the hulled grains (brown rice) of paddy rice (< or = 0.0002) was much lower than for that of upland (0.021). The transfer factors for both types of hulled grains were much lower than in the leaves. The technetium decontamination rate from hulled grains by polishing was 34%, the percentage of the weight decrease being 12%. The concentration of technetium in the soil solution collected from the paddy rice soil (flooded conditions) decreased rapidly with time due to its adsorption on the soil. In the upland rice soil (non-flooded) solution, the decrease in the technetium concentration was fairly slow. The low transfer factors for the paddy rice plants could be explained by the immobilization of technetium in the flooded soil. The oxidation-reduction potentials (Eh) in the flooded soil decreased rapidly with time. We conclude that technetium tracer added as TcO4- to flooded soil is readily transformed to an insoluble form (e.g. TcO2) under the reducing conditions provided by flooding. PMID:8558493

  16. The Influence of Dam Removal on Upland Soils

    NASA Astrophysics Data System (ADS)

    Lafrenz, M. D.; Bean, R. A.; Uthman, D.

    2011-12-01

    Driven largely by anadromous fish passage issues, several dams have been removed in the Pacific Northwest and several more are slated to be removed there and in other regions of North America. While much effort has gone into modeling and monitoring the geomorphic and ecologic response of stream channels to dam removal, little research has investigated changes in upland soils following inundation resulting from dam construction, and none had evaluated how these upland soils would respond to dewatering following dam removal. The removal of a relatively large dam - Marmot Dam on the Sandy River in Northwest Oregon, presented an opportunity to evaluate the effect of dewatering on what were formerly upland rather than floodplain soils. We compared the dewatered soils to downstream upland soils that had not been inundated and modified a "ripening" index, which had been developed to characterize dewatered estuary soils in Dutch polders, in order to evaluate the physical and chemical changes taking place in these soils. Two years following dam removal, the previously inundated soils have higher organic matter percentage, cation exchange capacity, and nitrogen levels than downstream soils that were not inundated; yet, this new riparian area is largely devoid of vegetation while the downstream soils maintain a thick (10 cm) O horizon. The carbon to nitrogen ratios (C:N) of upstream surface horizons are low (13:1) and increase markedly with soil depth (54:1); the C:N ratios of downstream soils are typical of other forested soils in this region (28:1 at the surface and 26:1 at depth). Prior to dam removal, it is likely that all upstream, inundated soils had high C:N ratios due to the persistent anaerobic conditions under the reservoir. Following dam removal, soil microbes needing to supplement their nitrogen consumption with soluble nitrogen likely out-competed higher plants for plant available nitrogen. The C:N ratio should have dropped to an equilibrium; this was not achieved at this location likely due to the coarse texture and corresponding low ripening value of the dewatered soils. Hence, native plants have not re-established in the new riparian area. The current resulting high levels of nitrogen in the upstream dewatered soil is anomalous for this region and could lead to colonization by non-native species in this and other newly dewatered ecosystems. Additionally, the lower sections of the dewatered upland soils are still saturated even though they stand perched several meters above the current floodplain; this evidence of reservoir "underflooding" will continue to affect soil development for an unknown amount of time and should be considered for any large dam removal project.

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

    NASA Astrophysics Data System (ADS)

    Gao, Jihui; Holden, Joseph; Kirkby, Mike

    2014-05-01

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

  18. Soil Data from Fire and Permafrost-Thaw Chronosequences in Upland Black Spruce (Picea mariana)

    E-print Network

    Soil Data from Fire and Permafrost-Thaw Chronosequences in Upland Black Spruce (Picea mariana and Permafrost-Thaw Chronosequences in Upland Black Spruce (Picea mariana) Stands near Hess Creek and Tok in Upland Black Spruce (Picea mariana) Stands near Hess Cree

  19. 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 (58Ë? 22' N, 26Ë? 43' E), in the southern part of Estonia. The soil of the experimental fields belongs according to the WRB soil classification, to the soils subgroups of Fibri-Dystric Histosols. The investigation areas were chosen by following criteria: (1) plantcover age; (2) cultivated plant species; (3) utilized agrotechnology; (4) comparisons between different factors were created by using natural growth areas of Vaccinaceae (natural bog area, Vaccinaceae growth area on mineral soil). For the investigation is important to choose areas with different age of plant covers, because according to plants age the surface of exhausted peat land will be covered in relation to the width of plants. The purpose of current article is to investigate the biological and chemical parameters co-influences in peat soil. Thus, the major interest is on the plant growth hormone indole-3-acetic acid distribution and dynamics in peat soil and dependence of plant cover, also its influence to the plants growth. Moreover, its contribution to yield and new growth area invasion will be discussed.

  20. 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).

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

    NASA Astrophysics Data System (ADS)

    Sty?a, 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 Pozna?, West Polish Lowland). The sites of investigation were located along Wysko? 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 ?max=525 nm with catechol as substrate by method of Perucci et al. (2000). In peat the highest activities of phenol oxidase was observed in the combinations marked as Shelterbelt and whereas the lowest - in Zbechy, Bridge and Hirudo. Activities of this enzyme in peat ranged from 15.35 to 38.33 ?mol h-1g d.m soil. Increased activities of phenol oxidase have been recorded on the depth 50-100cm - catotelm (21.74-38.33 ?mol h-1g d.m soil) in comparison with the depth 0-50cm - acrotelm (15.35-28.32 ?mol h-1g d.m soil). References Freeman, C., Ostle N.J., Fener, N., Kang H. 2004. A regulatory role for phenol oxidase during decomposition in peatlands. Soil Biology and Biochemistry, 36, 1663-1667. Matocha Ch.J., Haszler G.R., Grove J.H. 2004. Nitrogen fertilization suppresses soil phenol oxidase enzyme activity in no-tillage systems. Soil Science, 169/10, 708-714. Perucci P., Casucci C., Dumontet S. 2000. An improved method to evaluate the o-diphenol oxidase activity of soil. Soil Biology and Biochemistry, 32, 1927-1933. Sokolowska Z., Szajdak L., Matyka-Sarzy?ska D. 2005. Impact of the degree of secondary transformation on amid-base properties of organic compounds in mucks. Geoderma, 127, 80-90. Szajdak L., Szczepa?ski M., Bogacz A. 2007. Impact of secondary transformation of peat-moorsh soils on the decrease of nitrogen and carbon compounds in ground water. Agronomy Research, 5/2, 189-200.

  2. Biological Chlorine Cycling in Arctic Peat Soils

    NASA Astrophysics Data System (ADS)

    Zlamal, J. E.; Raab, T. K.; Lipson, D.

    2014-12-01

    Soils of the Arctic tundra near Barrow, Alaska are waterlogged and anoxic throughout most of the profile due to underlying permafrost. Microbial communities in these soils are adapted for the dominant anaerobic conditions and are capable of a surprising diversity of metabolic pathways. Anaerobic respiration in this environment warrants further study, particularly in the realm of electron cycling involving chlorine, which preliminary data suggest may play an important role in arctic anaerobic soil respiration. For decades, Cl was rarely studied outside of the context of solvent-contaminated sites due to the widely held belief that it is an inert element. However, Cl has increasingly become recognized as a metabolic player in microbial communities and soil cycling processes. Organic chlorinated compounds (Clorg) can be made by various organisms and used metabolically by others, such as serving as electron acceptors for microbes performing organohalide respiration. Sequencing our arctic soil samples has uncovered multiple genera of microorganisms capable of participating in many Cl-cycling processes including organohalide respiration, chlorinated hydrocarbon degradation, and perchlorate reduction. Metagenomic analysis of these soils has revealed genes for key enzymes of Cl-related metabolic processes such as dehalogenases and haloperoxidases, and close matches to genomes of known organohalide respiring microorganisms from the Dehalococcoides, Dechloromonas, Carboxydothermus, and Anaeromyxobacter genera. A TOX-100 Chlorine Analyzer was used to quantify total Cl in arctic soils, and these data were examined further to separate levels of inorganic Cl compounds and Clorg. Levels of Clorg increased with soil organic matter content, although total Cl levels lack this trend. X-ray Absorption Near Edge Structure (XANES) was used to provide information on the structure of Clorg in arctic soils, showing great diversity with Cl bound to both aromatic and alkyl groups. Incubations were conducted in the laboratory providing arctic soils with Clorg, and measurements taken to assess rates of organohalide respiration show an increase in chloride production due to microbial activity. Investigating these soils with diverse techniques affirms the importance of Cl-cycling in a pristine arctic tundra ecosystem.

  3. sSoil organic matter composition from of peat soils depending on land use

    NASA Astrophysics Data System (ADS)

    Ellerbrock, Ruth; Gerke, Horst, H.

    2013-04-01

    The soil organic matter (SOM) of peat often dominates soil properties because of the low mineral contents. The objective was to analyze SOM content and composition of peat soils as affected by (i) peat type and degradation status, (ii) water regime, and (iii) land use. Several peats in Canada and Germany were compared. The samples were analyzed with Fourier Transform infrared (FTIR) spectroscopy. FTIR indicated higher carboxyl (C=O) and alkyl (CH) group contents for the Canadian peats as compared to the German ones. The Canadian peat was an ombrotrophic bog while the German peats were fens. The role of the peat geneses for OM composition could be confirmed because the FTIR of the Canadian ombrotrophic bog was similar to that of another ombothrophic bog located in Lower Saxony, Germany. The SOM of the intensively drained fen of an arable site had a relatively higher C=O content as that of a less-drained grassland site. For fens with similar water regime, the OM composition was similar, except for effects of spatial heterogeneity. Such differences could be explained by differences in land use in the close surrounding near the sampling sites. Smaller FTIR absorption bands for C=O groups were found for samples located close to arable land as compared to samples from locations close to a forest (i.e., possibly shade or litter effects). These neighbourhood differences in SOM composition were similarly large as those those observed for different land use (i.e., arable sites or forests). The results indicate that SOM in peat soils is not only influenced by climate, land use or drainage but is also affected by the type of land use at sites in the close neighbourhood

  4. Microbial phototrophic fixation of atmospheric CO2 in China subtropical upland and paddy soils

    NASA Astrophysics Data System (ADS)

    Ge, Tida; Wu, Xiaohong; Chen, Xiaojuan; Yuan, Hongzhao; Zou, Ziying; Li, Baozhen; Zhou, Ping; Liu, Shoulong; Tong, Chengli; Brookes, Phil; Wu, Jinshui

    2013-07-01

    Autotrophic microorganisms, which can fix atmospheric CO2 to synthesize organic carbon, are numerous and widespread in soils. However, the extent and the mechanism of CO2 fixation in soils remain poorly understood. We incubated five upland and five paddy soils from subtropical China in an enclosed, continuously 14CO2-labeled, atmosphere and measured 14CO2 incorporated into soil organic matter (SOC14) and microbial biomass (MBC14) after 110 days. The five upland soils supported dominant crops soils (maize, wheat, sweet potato, and rapeseed) in the region, while all paddy soils were cultivated in a regime consisting of permanently-flooded double-cropping rice cultivation. The upland and paddy soils represented typical soil types (fluvisols and ultisols) and three landforms (upland, hill, and low mountain), ranging in total carbon from low (<10 g kg-1 soil organic carbon) to medium (10-20 g kg-1) to high (>20 g kg-1). Substantial amounts of 14CO2 were fixed into SOC14 (mean 20.1 ± 7.1 mg C kg-1 in upland soil, 121.1 ± 6.4 mg C kg-1 in paddy soil) in illuminated soils (12 h light/12 h dark), whereas no 14C was fixed in soils incubated in continuous darkness. We concluded that the microbial CO2 fixation was almost entirely phototrophic rather than chemotrophic. The rate of SOC14 synthesis was significantly higher in paddy soils than in upland soils. The SOC14 comprised means of 0.15 ± 0.01% (upland) and 0.65 ± 0.03% (paddy) of SOC. The extent of 14C immobilized as MBC14 and that present as dissolved organic C (DOC14) differed between soil types, accounting for 15.69-38.76% and 5.54-18.37% in upland soils and 15.57-40.03% and 3.67-7.17% of SOC14 in paddy soils, respectively. The MBC14/MBC and DOC14/DOC were 1.76-5.70% and 1.69-5.17% in the upland soils and 4.23-28.73% and 5.65-14.30% in the paddy soils, respectively. Thus, the newly-incorporated C stimulated the dynamics of DOC and MBC more than the dynamics of SOC. The SOC14 and MBC14 concentrations were highly significantly correlated (r = 0.946; P < 0.0001). We conclude that CO2 uptake by phototrophic soil microorganisms can contribute significantly to carbon assimilation in soil, and so warrants further future study.

  5. 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 equation to water flow under evaporation conditions to sphagnum moss and sphagnum peat is a feasible approximation.

  6. Erosion of upland hillslope soil organic carbon: Coupling field measurements with a sediment transport model

    E-print Network

    Heimsath, Arjun M.

    Erosion of upland hillslope soil organic carbon: Coupling field measurements with a sediment soil C measurements to quantify the erosion and temporal storage of soil organic carbon (SOC) within perturbation (Tennessee Valley (TV)) versus clay-rich soil creep (Black Diamond (BD)). The average SOC erosion

  7. Soil Physicochemical and Biological Properties of Paddy-Upland Rotation: A Review

    PubMed Central

    Lv, Teng-Fei; Chen, Yong; Westby, Anthony P.; Ren, Wan-Jun

    2014-01-01

    Paddy-upland rotation is an unavoidable cropping system for Asia to meet the increasing demand for food. The reduction in grain yields has increased the research interest on the soil properties of rice-based cropping systems. Paddy-upland rotation fields are unique from other wetland or upland soils, because they are associated with frequent cycling between wetting and drying under anaerobic and aerobic conditions; such rotations affect the soil C and N cycles, make the chemical speciation and biological effectiveness of soil nutrient elements varied with seasons, increase the diversity of soil organisms, and make the soil physical properties more difficult to analyze. Consequently, maintaining or improving soil quality at a desirable level has become a complicated issue. Therefore, fully understanding the soil characteristics of paddy-upland rotation is necessary for the sustainable development of the system. In this paper, we offer helpful insight into the effect of rice-upland combinations on the soil chemical, physical, and biological properties, which could provide guidance for reasonable cultivation management measures and contribute to the improvement of soil quality and crop yield. PMID:24995366

  8. Soil physicochemical and biological properties of paddy-upland rotation: a review.

    PubMed

    Zhou, Wei; Lv, Teng-Fei; Chen, Yong; Westby, Anthony P; Ren, Wan-Jun

    2014-01-01

    Paddy-upland rotation is an unavoidable cropping system for Asia to meet the increasing demand for food. The reduction in grain yields has increased the research interest on the soil properties of rice-based cropping systems. Paddy-upland rotation fields are unique from other wetland or upland soils, because they are associated with frequent cycling between wetting and drying under anaerobic and aerobic conditions; such rotations affect the soil C and N cycles, make the chemical speciation and biological effectiveness of soil nutrient elements varied with seasons, increase the diversity of soil organisms, and make the soil physical properties more difficult to analyze. Consequently, maintaining or improving soil quality at a desirable level has become a complicated issue. Therefore, fully understanding the soil characteristics of paddy-upland rotation is necessary for the sustainable development of the system. In this paper, we offer helpful insight into the effect of rice-upland combinations on the soil chemical, physical, and biological properties, which could provide guidance for reasonable cultivation management measures and contribute to the improvement of soil quality and crop yield. PMID:24995366

  9. Distribution of tetraether lipids in agricultural soils - differentiation between paddy and upland management

    NASA Astrophysics Data System (ADS)

    Mueller-Niggemann, C.; Utami, S. R.; Marxen, A.; Mangelsdorf, K.; Bauersachs, T.; Schwark, L.

    2015-10-01

    Insufficient knowledge of the composition and variation of isoprenoid and branched glycerol dialkyl glycerol tetraethers (GDGTs) in agricultural soils exists, despite of the potential effect of different management types (e.g. soil/water and redox conditions, cultivated plants) on GDGT distribution. Here, we determined the influence of different soil management types on the GDGT composition in paddy (flooded) and adjacent upland (non-flooded) soils, and if available also forest, bushland and marsh soils. To compare the local effects on GDGT distribution patterns, we collected comparable soil samples in various locations from tropical (Indonesia, Vietnam and Philippines) and subtropical (China and Italy) sites. We found that differences in the distribution of isoprenoid GDGTs (iGDGTs) as well as of branched GDGTs (brGDGTs) are predominantly controlled by management type and only secondarily by climatic exposition. In general upland soil had higher crenarchaeol contents than paddy soil, which on the contrary was more enriched in GDGT-0. The GDGT-0 / crenarchaeol ratio was 3-27 times higher in paddy soil and indicates the enhanced presence of methanogenic archaea, which were additionally linked to the number of rice cultivation cycles per year (higher number of cycles was coupled with an increase in the ratio). The TEX86 values were 1.3 times higher in upland, bushland and forest soils than in paddy soils. In all soils brGDGT predominated over iGDGTs, with the relative abundance of brGDGTs increasing from subtropical to tropical soils. Higher BIT values in paddy soils compared to upland soils together with higher BIT values in soil from subtropical climates indicate effects on the amounts of brGDGT through differences in management as well as climatic zones. In acidic soil CBT values correlated well with soil pH. In neutral to alkaline soils, however, no apparent correlation but an offset between paddy and upland managed soils was detected, which may suggest that soil moisture may exert an additional control on the CBT in these soils. Lower MBT' values and calculated temperatures (TMC) in paddy soils compared to upland soils may indicate a management (e.g. enhanced soil moisture through flooding practises) induced effect on mean annual soil temperature (MST).

  10. Effect of soil type and fertilizer management on archaeal community in upland field soils.

    PubMed

    Hoshino, Yuko Takada; Morimoto, Sho; Hayatsu, Masahito; Nagaoka, Kazunari; Suzuki, Chika; Karasawa, Toshihiko; Takenaka, Makoto; Akiyama, Hiroko

    2011-01-01

    The effects of soil and fertilizer types on archaeal communities were evaluated by real-time PCR and PCR-denaturing gradient gel electrophoresis (DGGE) targeting the 16S rRNA gene of total DNA directly extracted from upland field soils. Twelve experimental upland field plots containing four different soil types, i.e., Cumulic Andosol, Low-humic Andosol, Yellow Soil and Gray Lowland Soil, were maintained under three different fertilizer management systems for 8 years (chemical fertilizer, rice husks and cow manure, and pig manure, respectively). Two-way ANOVA and RDA analyses showed that the copy number and PCR-DGGE profile of archaeal 16S rRNA gene were affected mainly by soil type, especially between Andosol and non-Andosol, but were also influenced by fertilizer type. Among several soil chemical properties, total N content showed a significant correlation to archaeal community. Sequence analyses showed that most of the major DGGE bands corresponded to uncultured Crenarchaeota of Group I.1b that contained ammonia-oxidizing archaea (AOA). These sequences were separated into two clusters in the phylogenetic tree and each lineage showed a different response to total N content. PMID:21670564

  11. Factors affecting the mobilization of DOC and metals in a peat soil under a warmer scenario

    NASA Astrophysics Data System (ADS)

    Carrera, Noela; Barreal, María. Esther; Briones, María. Jesús I.

    2010-05-01

    Most climate change models predict an increase of temperature of 3-5°C in Southern Europe by the end of this century (IPCC 2007). However, changes in summer precipitations are more uncertain, and although a decrease in rainfall inputs is forecasted by most models, the magnitude of this effect has not been assessed properly (Rowell & Jones 2006). Peatland areas are very sensitive to climate change. In Galicia they survive in upland areas where cold temperatures and continuous moisture supply allow their presence. Besides abiotic factors, alterations in soil fauna activities can also affect peat turnover. Among them, enchytraeids are usually the most numerous invertebrate group in these systems and both temperature and moisture content regulate their abundances and vertical distribution. Previous studies have demonstrated that changes in their populations associated to increasing temperatures can significantly affect metal mobilization, namely iron and aluminium, together with an important decline in the acidity of the soil solution, which possibly eliminates one of the critical mechanisms restricting DOC release (Carrera et al., 2009). In this study we investigated whether changes in water content of the peat soil and soil invertebrate activities associated to increasing temperatures could alter the mobilization rates of Fe and Al and in turn, DOC. 72 undisturbed soil cores (6 cm diameter x 10 cm deep) with their associated vegetation were taken from a blanket bog in Galicia (NW Spain). Back at the laboratory they were sliced horizontally into two layers, (0-5cm and 5-10cm) which were defaunated by means of a wet extraction. Thereafter, the two soil layers derived from the same core were introduced in each microcosm by placing them in their original position but separated by a 1 mm nylon mesh to allow the vertical movements of the organisms. Half of the experimental units were adjusted to the used moisture values observed in the field (80% SWC, H1), whereas in the remaining half the moisture content was decreased to a lower value so that the activities of the soil organisms remained unaffected (60%, H2). Sixty enchytraeid individuals were inoculated into 18 units of each moisture treatment resulting in two animal treatments (+E and -E). Nine replicates of each treatment were incubated at 14°C and the rest were maintained at 19°C. Changes in enchytraeid populations during incubation were monitored by using a parallel series of 120 experimental units consisting of plastic containers which contained defaunated soil samples (two soil layers) separated by the nylon mesh and with the two moisture treatments as the microcosms (H1 and H2) following the same procedures as before. Next, the same number of enchytraeids was re-inoculated in half of these experimental units (+E and -E). The experiment run for 13 weeks; every 15 days, enchytraeid numbers, DOC, Fe and Al content in the leachates collected from each individual layer were determined. Results showed that both high temperature and moisture values promoted enchytraeid reproduction, with most individuals concentrated in the upper layer. This abundant enchytraeid population favoured the mobilization of DOC, Fe and Al to the soil solution. These findings suggest that modifications in soil faunal populations due to abiotic changes could enhance organic matter decomposition, contributing to the destabilization of these peatland systems. Increasing leaching of dissolved organic matter and metals could have negative implications, not only in terms of possible feed-backs to global warming but also as potential contaminants for aquatic ecosystems. References • Carrera N., Barreal M.E., Gallego P. & Briones M.J.I. (2009). Soil invertebrates control peatland C fluxes in response to warming. Functional Ecology 23: 637-648. • IPCC 2007. Climate change 2007. The Physical Science Basis. Solomon S., Qin D., Manning M., Chen Z., Marquis M., Averyt K.B., Tignor M. & Miller H.L. (Eds.). Cambridge University Press, Cambridge, UK. • Rowell D.P. & Jones R.G. (2006). Cause

  12. Organic matter composition of peat soils affected by genesis and drainage conditions

    NASA Astrophysics Data System (ADS)

    Ellerbrock, Ruth H.; Gerke, Horst H.; Heller, Christian; Leue, Martin

    2015-04-01

    The organic matter (OM) of peat soils often dominates the overall soil properties because of the low mineral contents. The quantity and quality of OM depends on the environmental conditions during peat genesis. We hypothesize that the OM quality in terms of the composition of OM functional groups can help to better understand the processes of peat soil development. The objective was to analyze OM composition of peat soils as a function of genesis, water regime, and land use. Three plant samples and 29 peat samples were taken from 7 sites (located northern Germany) which are different in peat genesis and land use intensity. The samples were analyzed with Fourier Transform infrared (FTIR) spectroscopy. The lower contents in CH functional groups for the fen samples as compared to bog samples reflect a higher biochemical activity in the fen as compared to the ombothrophic bog environments. The role of the peat genesis for OM composition could be confirmed by FTIR data of a Canadian ombrotrophic bog. The relative higher CH content in samples from non-drained as compared to those from drained fens could be explained by selective preservation due to anaerobic conditions. Increasing drainage intensity seems to cause a relative decrease in CH content and an increase in C=O content of the peat samples, reflecting an enhanced aerobic decomposition. The results suggest that peat genesis and drainage affects both OM content and composition substantially. However, the greater variability in OM composition as compared to that of bog samples indicate that SOM in peat soils is not only influenced by climate, land use or drainage but it is also affected by the type of land use at sites in the close neighborhood.

  13. 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 channels operated as the major transport domain.

  14. Soil warming in a cool-temperate mixed forest with peat soil enhanced heterotrophic and basal respiration rates but Q10 remained unchanged

    NASA Astrophysics Data System (ADS)

    Aguilos, M.; Takagi, K.; Liang, N.; Watanabe, Y.; Goto, S.; Takahashi, Y.; Mukai, H.; Sasa, K.

    2011-07-01

    We conducted soil warming experiment in a cool-temperate forest with peat soil in northern Japan, during the snowless seasons of 2007-2009. Our objective was to determine whether or not the heterotrophic respiration rate and the temperature sensitivity would change by soil warming. We elevated the soil temperature by 3 °C at 5 cm depth by means of overhead infrared heaters and continuously measured soil CO2 fluxes by using a fifteen-channel automated chamber system. Trenching treatment was also carried out to separate heterotrophic respiration and root respiration from the total soil respiration. The fifteen chambers were divided into three groups each with five replications for the control, unwarmed-trenched, and warmed-trenched treatments. We found that heterotrophic respiration contributed 71 % of the total soil respiration with the remaining 29 % accounted to autotrophic respiration. Soil warming enhanced heterotrophic respiration by 74 % (mean 6.11 ± 3.07 S.D. ?mol m-2 s-1) as compared to the unwarmed-trenched treatment (mean 3.52 ± 1.74 ?mol m-2 s-1). Soil CO2 efflux, however, was weakly correlated with soil moisture, probably because the volumetric soil moisture (33-46 %) was within a plateau region for root and microbial activities. The enhancement in heterotrophic respiration with soil warming in our study suggests that global warming will accelerate the loss of carbon from forested peatlands more seriously than other upland forest soils. On the other hand, soil warming did not cause significant change in the temperature sensitivity, Q10, (2.79 and 2.74 determined using hourly efflux data for unwarmed- and warmed-trenched, respectively), but increased their basal respiration rate at 0 °C (0.93 and 1.21 ?mol m-2 s-1, respectively). Results suggest that if we predict the soil heterotrophic respiration rate in future warmer environment using the current relationship between soil temperature and heterotrophic respiration, the rate can be underestimated.

  15. 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.

  16. Morphodynamics of headcut development and soil erosion in upland concentrated flows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In agricultural regions, gully erosion is now recognized as becoming a dominant source of soil loss, and the development and upstream migration of headcuts is critical to the initiation, incision, and dissection of these upland areas. The present investigation sought to examine the effect of soil t...

  17. Effect of Soil Stratification on the Development and Migration of Headcuts in Upland Concentrated Flows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were conducted to examine the effect of vertical stratification in soil erodibility on the development and migration of steady-state headcut scour holes in upland concentrated flows typical of agricultural fields. Packed soil beds with a pre-formed step were subjected to identical simul...

  18. Soil erosion predictions from upland areas – a discussion of selected RUSLE2 advances and needs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Obtaining more accurate soil loss estimates from upland areas is important for improving management practices on agricultural fields. Much of the soil erosion prediction research of the last 25 years has been concerned with this goal. The most widely used predictive relationships have been the Unive...

  19. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

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

  1. Short-term changes in upland soil erosion in England and Wales: 1999 to 2002

    NASA Astrophysics Data System (ADS)

    McHugh, Marianne

    2007-04-01

    Erosion was assessed on upland sites between October 2001 and June 2002, and compared with measurements of erosion made at the same sites during previous visits (1999). In addition to highlighting the scale of changes in erosion extent and nature over the sample period, the data were used to determine the influence of field site management and weather conditions on upland erosion. Results indicated that site erosion continued over the duration of the study, with most upland regions of England and Wales experiencing increases in erosion area and volume. On 52% of the 139 sites surveyed, increases in erosion extent resulted in 705 m 2 of newly exposed soil. Sheep were identified as the most frequent cause of this increased erosion, although the impacts of humans (through vehicle access, footpaths and drainage) were also extensive. Water-driven erosion processes were also prevalent in the maintenance of bare soil, both alone and in combination with other factors such as sheep, walkers and general weather conditions. Revegetation of bare soil was also an important feature of upland sites, resulting in a net decrease in erosion area on 63% of sites. The implications of these changes in erosion are discussed in the light of continuing changes in land use and management in the UK uplands, particularly those of reform of the EU Common Agricultural Policy (CAP), and in view of predicted changes in climate.

  2. Controls on Near-Surface Soil Moisture Dynamics within a Tidal Marsh-Forested Upland Coastal Environment

    E-print Network

    Lawrence, Deborah

    Controls on Near-Surface Soil Moisture Dynamics within a Tidal Marsh-Forested Upland Coastal moisture within the top 30 cm of soil for the study transect 2.10 Time-averaged soil moisture and soil on soil moisture dynamics for varying soil texture and elevation 3.1 Schematic diagram of root water

  3. Macronutrient concentration in plant parts of cotton fertilized with broiler Litter in a marginal upland Soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Effectiveness of surface-applied unincorporated litter relative to conventional inorganic fertilizers under no-till or conventional-till cotton (Gossypium hirsutum L.) production systems and the magnitude of litter benefit reduction associated with lack of incorporation in the upland soils of the so...

  4. Nutrient dynamics from broiler litter applied to no-till cotton in an upland soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surface-applying broiler litter to a no-till cotton field increases the potential for loss of manure nutrients from the fields in runoff events and volitization of the NH4-N. An experiment was conducted on an upland Atwood silt loam soil (fine-silty, mixed, thermic Typic Paleududalfs) at the Pontoto...

  5. Soil protozoa--An intensive study of population dynamics and community structure in an upland grassland

    E-print Network

    grassland§ Genoveva F. Esteban a,*, Ken J. Clarke b , Jose´ L. Olmo c , Bland J. Finlay a a Centre--the 1 ha area of upland grassland at the Macaulay Land Use Research Institute's Sourhope Research; Biodiversity; Grassland soils 1. Introduction Protozoa are by far the most abundant phagotrophic organisms

  6. Heterogeneity of biogenic gas ebullition in subtropical peat soils is revealed using time-lapse cameras

    NASA Astrophysics Data System (ADS)

    Comas, Xavier; Wright, William

    2012-04-01

    We tested a set of biogenic gas traps combined with time-lapse cameras to investigate the heterogeneous nature of biogenic gas ebullition events in subtropical peat soils at both the laboratory and field scale. The main findings are: (1) ebullition events in peat soils are highly heterogeneous; (2) estimates of flux rate are directly influenced by temporal scale of measurement with rapid (i.e., hourly) releasing events exceeding daily averages by one order of magnitude; and (3) increases in atmospheric pressure result in gas release from shallow peat soils into the atmosphere (i.e., ebullition), as indicated by a positive linear relation between changes in biogenic gas content and changes in atmospheric pressure. These results suggest that biogenic gas releases from shallow subtropical peat soils are not constant with larger than average daily fluxes being potentially released within hours during periods of increased atmospheric pressure. Furthermore, this study also shows the potential of time-lapse cameras for autonomously assessing the temporal variation in biogenic gas flux to the atmosphere from peatlands, and questions what temporal scale of measurement should be appropriate to infer dynamics of biogenic gas release in peat soils.

  7. Permafrost collapse alters soil carbon stocks, respiration, CH4 , and N2 O in upland tundra.

    PubMed

    Abbott, Benjamin W; Jones, Jeremy B

    2015-12-01

    Release of greenhouse gases from thawing permafrost is potentially the largest terrestrial feedback to climate change and one of the most likely to occur; however, estimates of its strength vary by a factor of thirty. Some of this uncertainty stems from abrupt thaw processes known as thermokarst (permafrost collapse due to ground ice melt), which alter controls on carbon and nitrogen cycling and expose organic matter from meters below the surface. Thermokarst may affect 20-50% of tundra uplands by the end of the century; however, little is known about the effect of different thermokarst morphologies on carbon and nitrogen release. We measured soil organic matter displacement, ecosystem respiration, and soil gas concentrations at 26 upland thermokarst features on the North Slope of Alaska. Features included the three most common upland thermokarst morphologies: active-layer detachment slides, thermo-erosion gullies, and retrogressive thaw slumps. We found that thermokarst morphology interacted with landscape parameters to determine both the initial displacement of organic matter and subsequent carbon and nitrogen cycling. The large proportion of ecosystem carbon exported off-site by slumps and slides resulted in decreased ecosystem respiration postfailure, while gullies removed a smaller portion of ecosystem carbon but strongly increased respiration and N2 O concentration. Elevated N2 O in gully soils persisted through most of the growing season, indicating sustained nitrification and denitrification in disturbed soils, representing a potential noncarbon permafrost climate feedback. While upland thermokarst formation did not substantially alter redox conditions within features, it redistributed organic matter into both oxic and anoxic environments. Across morphologies, residual organic matter cover, and predisturbance respiration explained 83% of the variation in respiration response. Consistent differences between upland thermokarst types may contribute to the incorporation of this nonlinear process into projections of carbon and nitrogen release from degrading permafrost. PMID:26301544

  8. Controls on soil solution nitrogen along an altitudinal gradient in the Scottish uplands.

    PubMed

    Jackson-Blake, L; Helliwell, R C; Britton, A J; Gibbs, S; Coull, M C; Dawson, L

    2012-08-01

    Nitrogen (N) deposition continues to threaten upland ecosystems, contributing to acidification, eutrophication and biodiversity loss. We present results from a monitoring study aimed at investigating the fate of this deposited N within a pristine catchment in the Cairngorm Mountains (Scotland). Six sites were established along an elevation gradient (486-908 m) spanning the key habitats of temperate maritime uplands. Bulk deposition chemistry, soil carbon content, soil solution chemistry, soil temperature and soil moisture content were monitored over a 5 year period. Results were used to assess spatial variability in soil solution N and to investigate the factors and processes driving this variability. Highest soil solution inorganic N concentrations were found in the alpine soils at the top of the hillslope. Soil carbon stock, soil solution dissolved organic carbon (DOC) and factors representing site hydrology were the best predictors of NO(3)(-) concentration, with highest concentrations at low productivity sites with low DOC and freely-draining soils. These factors act as proxies for changing net biological uptake and soil/water contact time, and therefore support the hypothesis that spatial variations in soil solution NO(3)(-) are controlled by habitat N retention capacity. Soil percent carbon was a better predictor of soil solution inorganic N concentration than mass of soil carbon. NH(4)(+) was less affected by soil hydrology than NO(3)(-) and showed the effects of net mineralization inputs, particularly at Racomitrium heath and peaty sites. Soil solution dissolved organic N concentration was strongly related to both DOC and temperature, with a stronger temperature effect at more productive sites. Due to the spatial heterogeneity in N leaching potential, a fine-scale approach to assessing surface water vulnerability to N leaching is recommended over the broad scale, critical loads approach currently in use, particularly for sensitive areas. PMID:22673176

  9. 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

  10. Spatial and vertical distribution of mercury in upland forest soils across the northeastern United States

    PubMed Central

    Richardson, Justin B.; Friedland, Andrew J; Engerbretson, Teresa R.; Kaste, James M.; Jackson, Brian P.

    2013-01-01

    Assessing current Hg pools in forest soils of the northeastern U.S. is important for monitoring changes in Hg cycling. The forest floor, upper and lower mineral horizons were sampled at 17 long-term upland forest sites across the northeastern U.S. in 2011. Forest floor Hg concentration was similar across the study region (274 ± 13 ?g kg?1) while Hg amount at northern sites (39 ± 6 g ha?1) was significantly greater than at western sites (11 ± 4 g ha?1). Forest floor Hg was correlated with soil organic matter, soil pH, latitude and mean annual precipitation and these variables explained approximately 70% of the variability when multiple regressed. Mercury concentration and amount in the lower mineral soil was correlated with Fe, soil organic matter and latitude, corresponding with Bs horizons of Spodosols (Podzols). Our analysis shows the importance of regional and soil properties on Hg accumulation in forest soils. PMID:23911621

  11. The effects of soil horizons and faunal excrement on bacterial distribution in an upland grassland soil.

    PubMed

    Bruneau, Patricia M C; Davidson, Donald A; Grieve, Ian C; Young, Iain M; Nunan, Naoise

    2005-03-01

    The density and spatial location of bacteria were investigated within different horizons of an upland grassland soil before and after a liming treatment to increase the numbers of large soil fauna. Bacterial cells were located by image analysis of stained thin sections and densities calculated from these data. Excrement from macro- and meso-fauna was identified using micromorphology and the densities of bacteria on specific areas of excrement measured by image analysis. There were significant differences among horizons in the density of bacterial cells, with the minimum density found in the horizon with least evidence of earthworm activity, but no difference in density between the organic H and organo-mineral Ah horizons. Soil improvement by liming significantly increased bacterial densities in all three horizons, with the greatest increase found in the horizon with the smallest density before liming. There were no differences in bacterial density between areas dominated by excrement from earthworms and excrement from enchytraeids, although densities in both areas were significantly increased by liming. Variability in bacterial density at spatial scales of less than 1 mm was linked to the occurrence of excrement. Bacterial densities within areas of both types of excrement were significantly greater than those in the surrounding soil. However, the frequency distribution of the ratios of density in excrement to that in the soil was bimodal, with a majority of occurrences having a ratio near 1 and only some 20-30% having a much larger ratio. These variations can probably be explained by variations in the age of the excrement and its suitability as a substrate. PMID:16329900

  12. High Potential for Iron Reduction in Upland Soils from Diverse Terrestrial Ecosystems

    NASA Astrophysics Data System (ADS)

    Yang, W. H.; Liptzin, D.

    2014-12-01

    Changes in the redox state of iron (Fe) can be coupled to the biogeochemical cycling of carbon (C), nitrogen, and phosphorus. The importance of Fe in catalyzing redox-driven biogeochemical cycling has been underappreciated in terrestrial ecosystems because they are not typically thought of as anaerobic environments. However, upland soils can experience anaerobic conditions following rainfall events or in microsites of high biological oxygen consumption. Measurements of Fe reduction rates in soils are difficult to compare among studies from different ecosystems, so we used the same assay to quantify potential Fe reduction in soils from upland environments (annual grassland, drained peatland pasture, and a rainforest) that varied in poorly crystalline Fe and total C. We slurried the soils and incubated them in a glovebox with a dinitrogen headspace. To evaluate the role of C availability in potential Fe reduction, we added sodium acetate daily at rates up to 0.6 mg C/g soil/d. We measured methane (CH4) production, acid- extractable Fe(II), citrate-ascorbate extractable Fe oxides, and pH over 5 days to determine the timing and magnitude of Fe reduction. In relatively dry soils (< 20 % gravimetric soil moisture), Fe reduction began after one day of anaerobic incubation as slurries, but all of the soils demonstrated high Fe reduction potential. On day 3, Fe reduction rates for the 0.05 mg C/g soil/d treatment were 1535 ± 51 ?g Fe(III) g-1 d-1 in the annual grassland soil, 1205 ± 42 ?g Fe(III) g-1 d-1 in the drained peatland soil, and 826 ± 54 ?g Fe(III) g-1 d-1 in the rainforest soil. This contrasts with the trend in poorly crystalline Fe oxide pools across the sites: 3.87 ± 0.06 ?g Fe(III) g-1 in the annual grassland, 7.49 ?g Fe(III) g-1 in the drained peatland, and 20.84 ± 0.19 ?g Fe(III) g-1 in the rainforest soil. Across all sites, small C additions (< 0.05 mg C/g soil/day) increased Fe reduction rates while larger C additions decreased Fe reduction. Iron reduction rates typically decreased by day 5, associated with an increase in CH4 concentrations suggesting that potentially reducible Fe was depleted. Our results suggest that upland soils have the potential to exhibit high short-term rates of Fe reduction that may play a role in driving C oxidation and other soil biogeochemical cycles during periods of anaerobiosis.

  13. Controls on soil solution nitrogen along an altitudinal gradient in the Scottish uplands

    NASA Astrophysics Data System (ADS)

    Jackson-Blake, L.; Helliwell, R. C.; Britton, A. J.; Gibbs, S.; Coull, M. C.; Dawson, L.

    2012-04-01

    Nitrogen (N) deposition continues to threaten upland ecosystems, contributing to acidification, eutrophication and biodiversity loss. We present results from a monitoring study aimed at investigating the fate of this deposited N within a relatively pristine catchment in the Cairngorm Mountains (Scotland). Six sites were established along an elevation gradient (486 - 908 m) spanning the key habitats of temperate maritime uplands. Bulk deposition chemistry, soil carbon content, soil solution chemistry, soil temperature and soil moisture content were monitored over a 5 year period, making this the first study of its kind in a maritime Alpine environment. Results were used to assess spatial variability in soil solution N and to investigate the factors and processes driving this variability. Highest soil solution inorganic N concentrations were found in the alpine soils at the top of the hillslope. Soil carbon stock, dissolved organic carbon concentration and factors representing site hydrology were the best predictors of nitrate concentration. These factors act as proxies for changing net biological uptake and soil/water contact time, and support the hypothesis that spatial variations in soil solution nitrate are controlled by habitat N retention capacity. Soil percent carbon was a better predictor of soil solution N concentration than mass of carbon. Ammonium was less affected by soil hydrology than nitrate and showed the effects of net mineralization inputs, particularly at Racomitrium heath and peaty sites. We hypothesize that high ammonium concentrations at the Racomitrium heath are related to the mineralization of microbial cell tissue during times of stress, largely in the absence of plant uptake. Due to the spatial heterogeneity in N leaching potential, a fine-scale approach to assessing surface water vulnerability to N leaching is recommended over the broad scale, critical loads approach currently in use, particularly for sensitive areas.

  14. Soil erosion on upland areas by rainfall and overland flow

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil erosion in agricultural watersheds is a systemic problem that has plagued mankind ever since the practice of agriculture began some 9,000 years ago. It is a worldwide problem, the severity of which varies from location to location depending on weather, soil type, topography, cropping practices,...

  15. Effect of paddy-upland rotation on methanogenic archaeal community structure in paddy field soil.

    PubMed

    Liu, Dongyan; Ishikawa, Hiroki; Nishida, Mizuhiko; Tsuchiya, Kazunari; Takahashi, Tomoki; Kimura, Makoto; Asakawa, Susumu

    2015-01-01

    Methanogenic archaea are strict anaerobes and demand highly reduced conditions to produce methane in paddy field soil. However, methanogenic archaea survive well under upland and aerated conditions in paddy fields and exhibit stable community. In the present study, methanogenic archaeal community was investigated in fields where paddy rice (Oryza sativa L.) under flooded conditions was rotated with soybean (Glycine max [L.] Merr.) under upland conditions at different rotation histories, by polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) and real-time quantitative PCR methods targeting 16S rRNA and mcrA genes, respectively. Soil samples collected from the fields before flooding or seeding, during crop cultivation and after harvest of crops were analyzed. The abundance of the methanogenic archaeal populations decreased to about one-tenth in the rotational plots than in the consecutive paddy (control) plots. The composition of the methanogenic archaeal community also changed. Most members of the methanogenic archaea consisting of the orders Methanosarcinales, Methanocellales, Methanomicrobiales, and Methanobacteriales existed autochthonously in both the control and rotational plots, while some were strongly affected in the rotational plots, with fatal effect to some members belonging to the Methanosarcinales. This study revealed that the upland conversion for one or longer than 1 year in the rotational system affected the methanogenic archaeal community structure and was fatal to some members of methanogenic archaea in paddy field soil. PMID:25113614

  16. Applied K fertilizer use efficiency in pineapples grown on a tropical peat soil under residues removal.

    PubMed

    Ahmed, Osumanu H; Ahmad, Husni M H; Musa, Hanafi M; Rahim, Anuar A; Rastan, Syed Omar S

    2005-01-21

    In Malaysia, pineapples are grown on peat soils, but most K fertilizer recommendations do not take into account K loss through leaching. The objective of this study was to determine applied K use efficiency under a conventionally recommended fertilization regime in pineapple cultivation with residues removal. Results showed that K recovery from applied K fertilizer in pineapple cultivation on tropical peat soil was low, estimated at 28%. At a depth of 0-10 cm, there was a sharp decrease of soil total K, exchangeable K, and soil solution K days after planting (DAP) for plots with K fertilizer. This decline continued until the end of the study. Soil total, exchangeable, and solution K at the end of the study were generally lower than prior values before the study. There was no significant accumulation of K at depths of 10-25 and 25-45 cm. However, K concentrations throughout the study period were generally lower or equal to their initial status in the soil indicating leaching of the applied K and partly explained the low K recovery. Potassium losses through leaching in pineapple cultivation on tropical peat soils need to be considered in fertilizer recommendations for efficient recovery of applied K. PMID:15674449

  17. Grain yield and arsenic uptake of upland rice inoculated with arbuscular mycorrhizal fungi in As-spiked soils.

    PubMed

    Wu, Fuyong; Hu, Junli; Wu, Shengchun; Wong, Ming Hung

    2015-06-01

    A pot trial was conducted to investigate the effects of three arbuscular mycorrhizal (AM) fungi species, including Glomus geosporum BGC HUN02C, G. versiforme BGC GD01B, and G. mosseae BGC GD01A, on grain yield and arsenic (As) uptake of upland rice (Zhonghan 221) in As-spiked soils. Moderate levels of AM colonization (24.1-63.1 %) were recorded in the roots of upland rice, and up to 70 mg kg(-1) As in soils did not seem to inhibit mycorrhizal colonization. Positive mycorrhizal growth effects in grain, husk, straw, and root of the upland rice, especially under high level (70 mg kg(-1)) of As in soils, were apparent. Although the effects varied among species of AM fungi, inoculation of AM fungi apparently enhanced grain yield of upland rice without increasing grain As concentrations in As-spiked soils, indicating that AM fungi could alleviate adverse effects on the upland rice caused by As in soils. The present results also show that mycorrhizal inoculation significantly (p?soils added with 70 mg?kg(-1) As. The present results suggest that AM fungi are able to mitigate the adverse effects with enhancing rice production when growing in As-contaminated soils. PMID:23292227

  18. Assessing the Impact of Land Management on Organic Matter Composition in Peat Soils

    NASA Astrophysics Data System (ADS)

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

    2010-05-01

    Peatlands are seen as important stores of terrestrial carbon, accounting for up to one-third of global soil carbon stocks. In some cases peatlands are shown to be emitters of carbon, in other cases carbon sinks depending on the site conditions and nature of degradation. However, carbon budget calculations carried out to date have a number of uncertainties associated with them and the composition of the carbon is generally not considered when determining carbon budgets. Carbon cycling in peat is driven by four key factors (Laiho, 2006):, environmental conditions (e.g. temperature, water table level), substrate quality (e.g. how recalcitrant the peat is), nutrients (e.g. nitrogen required to synthesis the carbon stocks) and microbial community (e.g. are the microbes present able to utilise the available substrate). Land management is also recognised as an additional driver, but the impacts of many types of management are poorly understood. Among the four drivers listed by Laiho (2006) substrate quality is seen as the most significant. To date, little work has been carried out to characterise the quality of organic matter in peat soils; rather crude estimates have been made as to the quantity of carbon that is stored in peatlands, yet without understanding the composition of the peat, limitations are imposed on calculations of rates of carbon loss from peatlands. This work seeks to examine how variations in the chemical composition of organic matter in peat varies with land use. The method published by Wieder and Starr (1998) was followed to determine eight fractions: soluble fats and waxes, hot water soluble, hollocellulose, cellulose, soluble phenolics, acid insoluble carbohydrates, water soluble carbohydrates and lignin. Samples were taken from burnt, grazed, drained, afforested and undisturbed sites at the Moor House UNESCO Biosphere Reserve in Northern England. The method was used to identify if differences were present in the recalcitrance of the peat and linked to gaseous carbon emissions data collected during fortnightly monitoring. R. Laiho (2006) Decomposition in peatlands: Reconciling seemingly contrasting results on the impacts of lowered water levels Soil Biology & Biochemistry, 38, 2011-2024. R.K. Wieder & S.T. Starr (1998) Quantitative determination of organic fractions in highly organic, Sphagnum peat soils Communications in Soil Science and Plant Analysis, 29, 847-857.

  19. Microbial activity of peat soils of boggy larch forests and bogs in the permafrost zone of central Evenkia

    NASA Astrophysics Data System (ADS)

    Grodnitskaya, I. D.; Karpenko, L. V.; Knorre, A. A.; Syrtsov, S. N.

    2013-01-01

    The microbial activity of peat soils was studied in boggy larch forests and in an oligo-mesotrophic bog in the basins of the Kochechum and Nizhnaya Tunguska rivers (central Evenkia). It was found that the organic matter transformation in the peat soils of all the plots is mainly performed by oligotrophic bacteria composing 88-98% of the total bacterial complex. The major contribution to the organic matter destruction belonged to the heterotrophic microorganisms, the activity of which depended on the permafrost depth and the soil temperature, the soil acidity, and the botanical composition of the peat. Peat soils were characterized by different activities as judged from their microbiological and biochemical parameters. The functioning of microbial communities in the studied ecotopes of the permafrost zone was within the range of natural variations, which pointed to their ecological stability.

  20. Screening of herbaceous plants for peat-enhanced rehabilitation of contaminated soil with oily sludge.

    PubMed

    Wang, Shijie; Zhang, Chao; Lu, Guilan; Li, Fasheng; Guo, Guanlin

    2016-01-01

    A batch pot experiment using nine herbaceous species were conducted for peat enhanced rehabilitation of contaminated soil with oily sludge in the initial contents of 0%, 1.3%, 7.4%, and 12.2%, respectively. The results showed that petroleum hydrocarbons removal, plant growth indices and enzyme activities varied depending on plant species and oil contents. Cotton, ryegrass and tall fescue were effective in the rehabilitation of oily sludge contaminated soils. The total petroleum hydrocarbon (TPH) removal ranged from 30.0% to 40.0% after 170 days of treatment. Plant biomass was shown to be the preferred indicator for screening phytoremediation plant because it was closely correlated with TPH removal and enzyme activities. Peat-enhanced plant rehabilitation could be a good strategy for the treatment of oily sludge contaminated saline soils. PMID:26114406

  1. RESPONSE OF UPLAND RICE GENOTYPES TO SOIL ACIDITY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In many parts of the world on highly weathered Oxisols, acidity is one of the major factors that contributes to the reduction of crop yields. In addition to liming, use of acid tolerant crop species or cultivars within species, is a complimentary solution to improve crop production on such soils. A ...

  2. Investigating methane flux dynamics in subtropical peat soils of the Everglades using hydrogeophysical methods

    NASA Astrophysics Data System (ADS)

    Comas, X.; Wright, W. J.; Heij, G.

    2012-12-01

    Methane is a dynamic atmospheric gas with high radiative forcing that directly influences climatic patterns. Peat soils are well recognized sources for atmospheric methane, and although the number of studies on methane dynamics has increased during the last two decades, most have focused on boreal peatlands. For that reason, low-latitude systems like the Everglades have traditionally been less studied, and have focused on discrete point measures (such as gas chambers) that provide little information on temporal patterns in methane flux variability. In this study, we present an array of hydrogeophysical techniques to investigate the temporal variability of methane dynamics in peat soils of the Everglades. Ground penetrating radar (GPR) is used here to estimate temporal changes in methane fluxes at different scales ranging from low frequency measurements in the field (1- 10 m), to high frequency measurements in peat blocks at the laboratory scale (<1 m). Discrete measurements in the field are combined with continuous measurements using a unique autonomous rail system at the laboratory scale to further constrain timing of methane releasing events. GPR measurements are paired with other techniques, including direct methods such as time-lapse cameras, gas traps and gas chromatography, and other indirect methods, such as capacitance probes. Our results show the potential of hydrogeophysical techniques to better understand: 1) the internal biogenic gas dynamics within the peat's matrix (i.e. methane production vs. release), 2) the temporal variability in methane gas releases (i.e. steady vs. episodic ebullition); and 3) the effect of atmospheric pressure on regulating ebullitive methane events. Our results suggest that ebullitive events in peat soils of the Everglades resulting in large rapid fluxes of methane to the atmosphere may occur during periods of high atmospheric pressure due to decreases in the bubble volume and subsequent increases in bubble mobility.

  3. No-till and conventional-till cotton response to broiler litter fertilization in an upland soil: lint yield

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effectiveness of poultry litter as cotton fertilizer is not well documented for upland soils in the southeastern USA where cotton may be grown under no-till and other soil conservation practices. The objective of this research was to measure the response of cotton to broiler litter fertilization...

  4. SEASONAL PHOSPHATASE ACTIVITY IN THREE CHARACTERISTIC SOILS OF THE ENGLISH UPLANDS POLLUTED BY LONG-TERM ATMOSPHERIC NITROGEN DEPOSITION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphomonoesterase activities were determined monthly during a seasonal cycle in three characteristic soil types of the English uplands that have been subject to long-term atmospheric nitrogen deposition. Activities (µmol para-nitrophenol per gram soil dry wt per hour) ranged between 83.9 - 307 in...

  5. Permafrost thaw and soil moisture driving CO2 and CH4 release from upland tundra

    NASA Astrophysics Data System (ADS)

    Natali, Susan M.; Schuur, Edward A. G.; Mauritz, Marguerite; Schade, John D.; Celis, Gerardo; Crummer, Kathryn G.; Johnston, Catherine; Krapek, John; Pegoraro, Elaine; Salmon, Verity G.; Webb, Elizabeth E.

    2015-03-01

    As permafrost degrades, the amount of organic soil carbon (C) that thaws during the growing season will increase, but decomposition may be limited by saturated soil conditions common in high-latitude ecosystems. However, in some areas, soil drying is expected to accompany permafrost thaw as a result of increased water drainage, which may enhance C release to the atmosphere. We examined the effects of ecosystem warming, permafrost thaw, and soil moisture changes on C balance in an upland tundra ecosystem. This study was conducted at a water table drawdown experiment, established in 2011 and located within the Carbon in Permafrost Experimental Heating Research project, an ecosystem warming and permafrost thawing experiment in Alaska. Warming and drying increased cumulative growing season ecosystem respiration by ~20% over 3 years of this experiment. Warming caused an almost twofold increase in decomposition of a common substrate in surface soil (0-10 cm) across all years, and drying caused a twofold increase in decomposition (0-20 cm) relative to control after 3 years of drying. Decomposition of older C increased in the dried and in the combined warmed + dried plots based on soil pore space 14CO2. Although upland tundra systems have been considered CH4 sinks, warming and ground thaw significantly increased CH4 emission rates. Water table depth was positively correlated with monthly respiration and negatively correlated with CH4 emission rates. These results demonstrate that warming and drying may increase loss of old permafrost C from tundra ecosystems, but the form and magnitude of C released to the atmosphere will be driven by changes in soil moisture.

  6. Distribution of radiocesium in the soil-plant systems of upland areas of Europe

    SciTech Connect

    Livens, F.R.; Horrill, A.D.; Singleton, D.L. )

    1991-04-01

    The distribution and behavior of Cs in the soil-plant systems at some upland sites in Northeastern Italy, Scotland, and Norway have been investigated. From the limited range of samples taken, there appears to be no dominant physicochemical control on the plant availability of Cs. The presence of micaceous minerals or illitic clays does not significantly inhibit Cs uptake, either because of recycling in the organic surface horizons or because of clay-organic complex formation. Lower plants (bryophytes and lichens) show the highest Cs accumulation. Of the higher plants, ericaceous species take up Cs more than the others.

  7. Phosphate addition and plant species alters microbial community structure in acidic upland grassland soil.

    PubMed

    Rooney, Deirdre C; Clipson, Nicholas J W

    2009-01-01

    Agricultural improvement (addition of fertilizers, liming) of seminatural acidic grasslands across Ireland and the UK has resulted in significant shifts in floristic composition, soil chemistry, and microbial community structure. Although several factors have been proposed as responsible for driving shifts in microbial communities, the exact causes of such changes are not well defined. Phosphate was added to grassland microcosms to investigate the effect on fungal and bacterial communities. Plant species typical of unimproved grasslands (Agrostis capillaris, Festuca ovina) and agriculturally improved grasslands (Lolium perenne) were grown, and phosphate was added 25 days after seed germination, with harvesting after a further 50 days. Phosphate addition significantly increased root biomass (p < 0.001) and shoot biomass (p < 0.05), soil pH (by 0.1 U), and microbial activity (by 5.33 mg triphenylformazan [TPF] g(-1) soil; p < 0.001). A slight decrease (by 0.257 mg biomass-C g(-1) soil; p < 0.05) in microbial biomass after phosphate addition was found. The presence of plant species significantly decreased soil pH (p < 0.05; by up to 0.2 U) and increased microbial activity (by up to 6.02 mg TPF g(-1) soil) but had no significant effect on microbial biomass. Microbial communities were profiled using automated ribosomal intergenic spacer analysis. Multidimensional scaling plots and canonical correspondence analysis revealed that phosphate addition and its interactions with upland grassland plant species resulted in considerable changes in the fungal and bacterial communities of upland soil. The fungal community structure was significantly affected by both phosphate (R = 0.948) and plant species (R = 0.857), and the bacterial community structure was also significantly affected by phosphate (R = 0.758) and plant species (R = 0.753). Differences in microbial community structure following P addition were also revealed by similarity percentage analysis. These data suggest that phosphate application may be an important contributor to microbial community structural change during agricultural management of upland grasslands. PMID:18581037

  8. A cost-efficient method to assess carbon stocks in tropical peat soil

    NASA Astrophysics Data System (ADS)

    Warren, M. W.; Kauffman, J. B.; Murdiyarso, D.; Anshari, G.; Hergoualc'h, K.; Kurnianto, S.; Purbopuspito, J.; Gusmayanti, E.; Afifudin, M.; Rahajoe, J.; Alhamd, L.; Limin, S.; Iswandi, A.

    2012-11-01

    Estimation of belowground carbon stocks in tropical wetland forests requires funding for laboratory analyses and suitable facilities, which are often lacking in developing nations where most tropical wetlands are found. It is therefore beneficial to develop simple analytical tools to assist belowground carbon estimation where financial and technical limitations are common. Here we use published and original data to describe soil carbon density (kgC m-3; Cd) as a function of bulk density (gC cm-3; Bd), which can be used to rapidly estimate belowground carbon storage using Bd measurements only. Predicted carbon densities and stocks are compared with those obtained from direct carbon analysis for ten peat swamp forest stands in three national parks of Indonesia. Analysis of soil carbon density and bulk density from the literature indicated a strong linear relationship (Cd = Bd × 495.14 + 5.41, R2 = 0.93, n = 151) for soils with organic C content > 40%. As organic C content decreases, the relationship between Cd and Bd becomes less predictable as soil texture becomes an important determinant of Cd. The equation predicted belowground C stocks to within 0.92% to 9.57% of observed values. Average bulk density of collected peat samples was 0.127 g cm-3, which is in the upper range of previous reports for Southeast Asian peatlands. When original data were included, the revised equation Cd = Bd × 468.76 + 5.82, with R2 = 0.95 and n = 712, was slightly below the lower 95% confidence interval of the original equation, and tended to decrease Cd estimates. We recommend this last equation for a rapid estimation of soil C stocks for well-developed peat soils where C content > 40%.

  9. Fire effects on peat and organo-mineral soils of Meshchera plain

    NASA Astrophysics Data System (ADS)

    Tsibart, Anna; Koshovskii, Timur; Gamova, Natalia; Kovach, Roman

    2015-04-01

    The fire effects the soil properties depend on soil type and on their vulnerability to fires. The most of available data is devoted to changes in organo-mineral soils. But the peat fires can cause deeper changes in soil profiles, especially in case of drained peat soils. Now the lack of information exists in the sphere of the comparison of these fire types on soil cover. Meshchera plain (Moscow and Ryazan Regions, Russia) has different soil types. Moreover peatlands were partly drained, and the plain was affected by numerous fires of different time. So there is a need of detailed post-fire soil investigations in this region. During current research the soils Meshchera plain subjected by wildfires of 2002, 2007, 2010 and 2012 were studied. A total of 32 profiles including background and post-fire histosols, histic and sod podzols were investigated. Moreover the detailed description of vegetation cover was conducted. The samples were taken from genetic horizons. The morfological properties of soil profiles were sudied and the samples were analysed on organic carbon, pH, macroelements, magnetic susceptibility. After the wildfires changes in morfological and physico-chemical properties of soils were detected in most cases. The formation of ash and charry horizons was observed only in cases of peat soils affecetd by intense fires, and all post-fire drained peat soils had thick ash horizons even after 10 years after the fires. The significant loss of organic matter took place after burning. But almost immediately after the fires new stage of humus formation usually started. For instance, in post-fire histosols in 2 years after the burning the content of organic carbon reached to 10-12 % in upper horizons. ph values in background histosols were approximately 4-5. After the fire pH increased in these soil type to 8, and two years after the fire event pH decreased to 6-7. In podzols pH values returned to the pre-fire level 4-5 in two years. The magnetic susceptibility of soil samples in background histosols was 2-40 ×10-6 cm3/g. After the fires it increased in ash horizons up to 250 ×10-6 cm3/g. In sod podzols the changes also occurred. Background podzols had 2- 5×10-6 cm3/g. Post-fire horizons had up to 50- 60×10-6 cm3/g after the fires. And even 10 years later the differences between post-fire and background soils preserved. So this parameter could be used as an indicator of fire events in soil profiles. After the fire the significant changes occurred in horizon mineral composition. Ash horizons had elevated concentrations of Al2O3 (9-17%), Fe2O3 (4-11%), P2O3 (1-1,8 %), CaO (1,9-2,8 %) and K2O (0,1-1,9%). The observed trends were similar for histosols and for histic podzols. And the changes in horizon mineral composition remained 2 and 10 years after the fire. So the more significant morphological and chemical changes occurred in the profiles of histosols, especially fire altered the soils of drained peatlands. These soil type keeps changes even 10 years after the fires.

  10. Biochar as a Substitute for Peat in Greenhouse Growing Media: Soil Water Characteristics and Carbon Leaching Dynamics

    NASA Astrophysics Data System (ADS)

    Johnson, M. S.; Hilbert, I.; Jollymore, A. J.

    2012-12-01

    Biochar (charcoal derived from waste biomass via pyrolysis) has the potential to be used as part of regional scale carbon sequestration strategies. By providing a stable form of carbon that is resistant to decay in soils, biochar can be utilized in a wide range of applications to improve the sustainability of land use management practices. Due to its high water holding capacity, surface area and charge density, it could provide a substitute for peat that is widely used in horticultural activities. Globally, peat production in 2010 amounted to 23.4 Mt, with more than a third of this used for horticulture. In Canada, essentially all peat produced is used for horticulture, with each ton of peat extracted also contributing about 0.7 t CO2e in combined greenhouse gas emissions related to production, transportation and use of peat. We evaluated biochar produced on farm from red alder as a peat substitute in terms of soil water characteristics and carbon leaching in greenhouse growing media (e.g. potting mix). Biochar mixing ratios of 10% (v/v) and greater provided water holding capacity equivalent to peat-based potting mixes. We also present results from a laboratory wetting experiment in which we characterized leachate for dissolved organic carbon (DOC) concentration and DOC characteristics using spectral methods (uV-Vis and fluorescence spectroscopy).

  11. Mississippi Basin Carbon Project: upland soil database for sites in Nishnabotna River basin, Iowa

    USGS Publications Warehouse

    Harden, J.W.; Fries, T.L.; Haughy, R.; Kramer, L.; Zheng, Shuhui

    2001-01-01

    The conversion of land from its native state to an agricultural use commonly results in a significant loss of soil carbon (Mann, 1985; Davidson and Ackerman, 1993). Globally, this loss is estimated to account for as much as 1/3 of the net CO2 emissions for the period of 1850 to 1980 (Houghton and others, 1983). Roughly 20 to 40 percent of original soil carbon is estimated to be lost as CO2 as a result of agricultural conversion, or "decomposition enhancement". Global models use this estimate along with land conversion data to provide agricultural contributions of CO2 emissions for global carbon budgets (Houghton and others, 1983; Schimel, 1995). Soil erosion rates are significantly (10X) higher on croplands than on their undisturbed equivalents (Dabney and others, 1997). Most of the concern over erosion is related to diminished productivity of the uplands (Stallings, 1957; McGregor and others, 1969; Rhoton, 1990) or to increased hazards and navigability of the lowlands in the late 1800's to early 1900's. Yet because soil carbon is concentrated at the soil surface, with an exponential decline in concentration with depth (Harden et al, 1999), it is clear that changes in erosion rates seen on croplands must also impact soil carbon storage and terrestrial carbon budgets as well. As yet, erosional losses of carbon are not included in global carbon budgets explicitly as a factor in land conversion nor implicitly as a portion of the decomposition enhancement. However, recent work by Lal and others (1995) and by Stallard (1998) suggests that significant amounts of eroded soil may be stored in man-made reservoirs and depositional environments as a result of agricultural conversion. Moreover, Stallard points out that eroding soils have the potential for replacing part of the carbon trapped in man-made reservoirs. If true, then the global carbon budget may grossly underestimate or ignore a significant sink term resulting from the burial of eroded soil.

  12. Mississippi Basin Carbon Project; upland soil database for sites in Yazoo Basin, northern Mississippi

    USGS Publications Warehouse

    Harden, J.W.; Fries, T.L.; Huntington, T.G.

    1999-01-01

    The conversion of land from its native state to an agricultural use commonly results in a significant loss of soil carbon (Mann, 1985; Davidson and Ackerman, 1993). Globally, this loss is estimated to account for as much as 1/3 of the net CO2 emissions for the period of 1850 to 1980 (Houghton et al, 1983). Roughly 20 to 40 percent of original soil carbon is estimated to be lost as CO2 as a result of agricultural conversion, or 'decomposition enhancement', and global models use this estimate along with land conversion data to provide agricultural contributions of CO2 emissions for global carbon budgets (Houghton and others, 1983; Schimel, 1995). As yet, erosional losses of carbon are not included in global carbon budgets explicitly as a factor in land conversion nor implicitly as a portion of the decomposition enhancement. However, recent work by Lal et al (1995) and by Stallard (1998) suggests that significant amounts of eroded soil may be stored in man-made reservoirs and depositional environments as a result of agricultural conversion. Moreover, Stallard points out that if eroding soils have the potential for replacing part of the carbon trapped in man-made reservoirs, then the global carbon budget may grossly underestimate or ignore a significant sink term resulting from the burial of eroded soil. Soil erosion rates are significantly (10X) higher on croplands than on their undisturbed equivalents (Dabney et al, 1997). Most of the concern over erosion is related to diminished productivity of the uplands (Stallings, 1957; McGregor et al, 1993; Rhoton and Tyler, 1990) or to increased hazards and navigability of the lowlands in the late 1800's to early 1900's. Yet because soil carbon is concentrated at the soil surface, with an exponential decline in concentration with depth, it is clear that changes in erosion rates seen on croplands must also impact soil carbon storage and terrestrial carbon budgets as well.

  13. Conversion of upland to paddy field specifically alters the community structure of archaeal ammonia oxidizers in an acid soil

    NASA Astrophysics Data System (ADS)

    Alam, M. S.; Ren, G. D.; Lu, L.; Zheng, Y.; Peng, X. H.; Jia, Z. J.

    2013-08-01

    The function of ammonia-oxidizing archaea (AOA) and bacteria (AOB) depends on the major energy-generating compounds (i.e., ammonia and oxygen). The diversification of AOA and AOB communities along ecological gradients of substrate availability in a complex environment have been much debated but rarely tested. In this study, two ecosystems of maize and rice crops under different fertilization regimes were selected to investigate the community diversification of soil AOA and AOB upon conversion of an upland field to a paddy field and long-term field fertilization in an acid soil. Real-time quantitative polymerase chain reaction of ammonia monooxygenase (amoA) genes demonstrated that the abundance of AOA was significantly stimulated after conversion of upland to paddy soils for more than 100 yr, whereas a slight decline in AOB numbers was observed. Denaturing gradient gel electrophoresis fingerprints of amoA genes further revealed remarkable changes in the community compositions of AOA after conversion of aerobic upland to flooded paddy field. Sequencing analysis revealed that upland soil was dominated by AOA within the soil group 1.1b lineage, whereas the marine group 1.1a-associated lineage predominated in AOA communities in paddy soils. Irrespective of whether the soil was upland or paddy soil, long-term field fertilization led to increased abundance of amoA genes in AOA and AOB compared with control treatments (no fertilization), whereas archaeal amoA gene abundances outnumbered their bacterial counterparts in all samples. Phylogenetic analyses of amoA genes showed that Nitrosospira cluster-3-like AOB dominated bacterial ammonia oxidizers in both paddy and upland soils, regardless of fertilization treatment. The results of this study suggest that the marine group 1.1a-associated AOA will be better adapted to the flooded paddy field than AOA ecotypes of the soil group 1.1b lineage, and indicate that long-term flooding is the dominant selective force driving the community diversification of AOA populations in the acid soil tested.

  14. Modeling relationships between water table depth and peat soil carbon loss in Southeast Asian plantations

    NASA Astrophysics Data System (ADS)

    Carlson, Kimberly M.; Goodman, Lael K.; May-Tobin, Calen C.

    2015-07-01

    Plantation-associated drainage of Southeast Asian peatlands has accelerated in recent years. Draining exposes the upper peat layer to oxygen, leading to elevated decomposition rates and net soil carbon losses. Empirical studies indicate positive relationships between long-term water table (WT) depth and soil carbon loss rate in peatlands. These correlations potentially enable using WT depth as a proxy for soil carbon losses from peatland plantations. Here, we compile data from published research assessing WT depth and carbon balance in tropical plantations on peat. We model net carbon loss from subsidence studies, as well as soil respiration (heterotrophic and total) from closed chamber studies, as a function of WT depth. WT depth across all 12 studies and 59 sites is 67 ± 20 cm (mean ± standard deviation). Mean WT depth is positively related to net carbon loss, as well as soil respiration rate. Our models explain 45% of net carbon loss variation and 45-63% of soil respiration variation. At a 70 cm WT depth, the subsidence model suggests net carbon loss of 20 tC ha-1 yr-1 (95% confidence interval (CI) 18-22 tC ha-1 yr-1) for plantations drained for >2 yr. Closed chamber-measured total soil respiration at this depth is 20 tC-CO2 ha-1 yr-1 (CI 17-24 tC-CO2 ha-1 yr-1) while heterotrophic respiration is 17 tC-CO2 ha-1 yr-1 (CI 14-20 tC-CO2 ha-1 yr-1), ˜82% of total respiration. While land use is not a significant predictor of soil respiration, WT depths are greater at acacia (75 ± 16 cm) than oil palm (59 ± 15 cm) sample sites. Improved spatio-temporal sampling of the full suite of peat soil carbon fluxes—including fluvial carbon export and organic fertilizer inputs—will clarify multiple mechanisms leading to carbon loss and gain, supporting refined assessments of the global warming potential of peatland drainage.

  15. Multiple season, field scale exploration of biogenic gas dynamics in two peat soils of the Florida Everglades using hydrogeophysics

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

    Peatlands are known to release significant amounts of methane (CH4) and carbon dioxide (CO2) to the atmosphere. However, uncertainties still remain regarding the spatio-temporal distribution and triggering mechanisms of gas releasing events from peat soils. Furthermore, most research regarding peatland gas dynamics has historically been focused on high latitude peatlands, while recent works have suggested gas production rates from low-latitude peat soils may be higher than those from colder climates. Varying temporal and spatial scales have also shown marked differences in flux rates, thus questioning the appropriate scale for gas flux quantification. Ground penetrating radar (GPR) is a geophysical tool that has successfully been used in the past to non-invasively investigate the release of biogenic gasses from northern peat soils, and has only recently been used in the subtropical Florida Everglades. This study is based on an array of measurements at four field sites, spanning two different peat types (Loxahatchee and Everglades peats) of the Florida Everglades over a period of two years. At each site, gas contents within the soil are monitored using the GPR method, which is supported by direct gas flux measurements using flux chambers and time-lapse photography, and surface deformation is monitored using differential leveling. Resulting data highlight the variability of gas dynamics based on spatial, temporal, and soil compositional differences.

  16. The Dependence of Peat Soil Hydraulic Conductivity on Dominant Vegetation Type in Mountain Fens

    NASA Astrophysics Data System (ADS)

    Crockett, A. C.; Ronayne, M. J.; Cooper, D. J.

    2014-12-01

    The peat soil within fen wetlands provides water storage that can substantially influence the hydrology of mountain watersheds. In this study, we investigated the relationship between hydraulic conductivity and vegetation type for fens occurring in Rocky Mountain National Park (RMNP), Colorado, USA. Vegetation in RMNP fens can be dominated by woody plants and shrubs, such as willows; by mosses; or by herbaceous plants such as sedges. Fens dominated by each vegetation type were selected for study. Six fens were investigated, all of which are in the Colorado River watershed on the west side of RMNP. For each site, soil hydraulic conductivity was measured at multiple locations using a single-ring infiltrometer. As a result of the shallow water table in these fens (the water table was always within 10 cm of the surface), horizontal hydraulic gradients were produced during the field tests. The measured infiltration rates were analyzed using the numerical model HYDRUS. In order to determine the hydraulic conductivity, a parameter estimation problem was solved using HYDRUS as the forward simulator. Horizontal flow was explicitly accounted for in the model. This approach produced more accurate estimates of hydraulic conductivity than would be obtained using an analytical solution that assumes strictly vertical flow. Significant differences in hydraulic properties between fens appear to result at least in part from the effects of different dominant vegetation types on peat soil formation.

  17. EVALUATION OF ENHANCED VOC REMOVAL WITH SOIL FRACTURING IN THE SRS UPLAND UNIT

    SciTech Connect

    Riha, B

    2005-10-31

    The Environmental Restoration Technology Section (ERTS) of the Savannah River National Laboratory (SRNL) conducted pilot scale testing to evaluate the effectiveness of using hydraulic fracturing as a means to improve soil vapor extraction (SVE) system performance. Laboratory and field research has shown that significant amounts of solvents can be entrapped in low permeability zones by capillary forces and removal by SVE can be severely limited due to low flow rates, mass transfer resistance of the hydrophobic compounds by trapped interparticle water, and diffusion resistance. Introducing sand-filled fractures into these tight zones improves the performance of SVE by (1) increasing the overall permeability of the formation and thereby increasing SVE flow rates, (2) shortening diffusion pathways, and (3) increasing air permeability by improving pore water removal. The synergistic effect of the fracture well completion methods, fracture and flow geometry, and pore water removal appears to increase the rate of solvent mass removal over that of increasing flow rate alone. A field test was conducted where a conventional well in the SRS Upland Unit was tested before and after hydraulic fracturing. ERTS teamed with Clemson University through the South Carolina University and Education Foundation (SCUREF) program utilizing their expertise in fracturing and fracture modeling. The goals of the fracturing pilot testing were to evaluate the following: (1) The effect of hydraulic fractures on the performance of a conventional well. This was the most reliable way to remove the effects of spatial variations in permeability and contaminant distribution on relative well performance. It also provided data on the option of improving the performance of existing wells using hydraulic fractures. (2) The relative performance of a conventional SVE well and isolated hydraulic fractures. This was the most reliable indicator of the performance of hydraulic fractures that could be created in a full-scale implementation. The SVE well, monitoring point arrays and four fracturing wells were installed and the well testing has been completed. Four fractures were successfully created the week of July 25, 2005. The fractures were created in an open area at the bottom of steel well casing by using a water jet to create a notch in the soil and then injecting a guar-sand slurry into the formation. The sand-filled fractures increase the effective air permeability of the subsurface formation diffusion path lengths for contaminant removal. The primary metrics for evaluation were an increase in SVE flow rates in the zone of contamination and an increase in the zone of influence. Sufficient testing has been performed to show that fracturing in the Upland Unit accelerates SVE solvent remediation and fracturing can increase flow rates in the Upland Unit by at least one order of magnitude.

  18. Investigating carbon flux variability in subtropical peat soils of the Everglades using hydrogeophysical methods

    NASA Astrophysics Data System (ADS)

    Comas, Xavier; Wright, William

    2014-08-01

    The spatial and temporal variability in accumulation and release of greenhouse gases (mainly methane and carbon dioxide) to the atmosphere from peat soils remains very uncertain. The use of near-surface geophysical methods such as ground penetrating radar (GPR) has proven useful during the last decade to expand scales of measurement as related to in situ gas distribution and dynamics beyond traditional methods (i.e., gas chambers). However, this approach has focused exclusively on boreal peatlands, while no studies in subtropical systems like the Everglades using these techniques exist. In this paper GPR is combined with gas traps, time-lapse cameras, gas chromatography, and surface deformation measurements to explore biogenic gas dynamics (mainly gas buildup and release) in two locations in the Everglades. Similar to previous studies in northern peatlands, our data in the Everglades show a statistically significant correlation between the following: (1) GPR-estimated gas content and gas fluxes, (2) GPR-estimated gas content and surface deformation, and (3) atmospheric pressure and both GPR-estimated gas content and gas flux. From these results several gas-releasing events ranging between 33.8 and 718.8 mg CH4 m-2 d-1 were detected as identified by the following: (1) decreases in GPR-estimated gas content within the peat matrix, (2) increases in gas fluxes captured by gas traps and time-lapse cameras, and (3) decreases in surface deformation. Furthermore, gas-releasing events corresponded to periods of high atmospheric pressure. Changes in gas accumulation and release were attributed to differences in seasonality and peat soil type between sites. These results suggest that biogenic gas releases in the Everglades are spatially and temporarily variable. For example, flux events measured at hourly scales were up to threefold larger when compared to daily fluxes, therefore suggesting that flux measurements decline when averaged over longer time spans. This research therefore questions what the appropriate spatial and temporal scale of measurement is necessary to properly capture the dynamics of biogenic gas release in subtropical peat soils.

  19. Soil-atmosphere trace gas exchange from tropical oil palm plantations on peat

    NASA Astrophysics Data System (ADS)

    Arn Teh, Yit; Manning, Frances; Zin Zawawi, Norliyana; Hill, Timothy; Chocholek, Melanie; Khoon Kho, Lip

    2015-04-01

    Oil palm is the largest agricultural crop in the tropics, accounting for 13 % of all tropical land cover. Due to its large areal extent, oil palm cultivation may have important implications not only for terrestrial stores of C and N, but may also impact regional and global exchanges of material and energy, including fluxes of trace gases and water vapor. In particular, recent expansion of oil palm into tropical peatlands has raised concerns over enhanced soil C emissions from degradation of peat, and elevated N-gas fluxes linked to N fertilizer application. Here we report our preliminary findings on soil carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes from a long-term, multi-scale project investigating the C, N and greenhouse gas (GHG) dynamics of oil palm ecosystems established on peat soils in Sarawak, Malaysian Borneo. Flux chamber measurements indicate that soil CO2, CH4 and N2O fluxes averaged 20.0 ± 16.0 Mg CO2-C ha-1 yr-1, 37.4 ± 29.9 kg CH4-C ha-1 yr-1 and 4.7 ± 4.2 g N2O-N ha-1 yr-1, respectively. Soil CO2 fluxes were on par with other drained tropical peatlands; whereas CH4 fluxes exceeded observations from similar study sites elsewhere. Nitrous oxide fluxes were in a similar range to fluxes from other drained tropical peatlands, but lower than emissions from mineral-soil plantations by up to three orders of magnitude. Fluxes of soil CO2 and N2O were spatially stratified, and contingent upon the distribution of plants, deposited harvest residues, and soil moisture. Soil CO2 fluxes were most heavily influenced by the distribution of palms and their roots. On average, autotrophic (root) respiration accounted for approximately 78 % of total soil CO2 flux, and total soil respiration declined steeply away from palms; e.g. soil CO2 fluxes in the immediate 1 m radius around palms were up to 6 times greater than fluxes in inter-palm spaces due to higher densities of roots. Placement of harvest residues played an important - but secondary - role in modulating soil CO2 fluxes; soil respiration rates doubled in areas where harvest residues were deposited, reflecting an enhanced input of labile organic matter for decomposition. In contrast, N2O fluxes were best-predicted by the distribution of harvest residues, and were only weakly related to plant distributions or soil moisture. For example, N2O fluxes from harvest residue piles were up to twice of the overall plot-average. In contrast, N2O fluxes showed no clear pattern around palms or in inter-palm spaces; this finding is surprising because N fertilizers are applied within the 1 m radius around palms, and we expected to observe enhanced N2O fluxes in areas of greater fertilizer input. This suggests that palms may be a strong competitor for N in these ecosystems, and that fertilizer application may more closely match overall plant demand than in mineral-soil plantations. Overall, the spatial patterning of soil CO2 and N2O fluxes implies that soil biogeochemical processes are predictably distributed in space, potentially making it easier to model and constrain fluxes of these soil-derived GHGs.

  20. [Responses of soil nematode communities to long-term application of inorganic fertilizers in upland red soil].

    PubMed

    Zhang, Wei; Liu, Man-Qiang; He, Yuan-Qiu; Fan, Jian-Bo; Chen, Yan

    2014-08-01

    Soil biota plays a key role in ecosystem functioning of red soil. Based on the long-term inorganic fertilization field experiment (25-year) in an upland red soil, the impacts of different inorganic fertilization managements, including NPK (nitrogen, phosphorus and potassium fertilizers), NPKCaS (NPK plus gypsum fertilizers), NP (nitrogen and phosphorus fertilizers), NK (nitrogen and potassium fertilizers) and PK (phosphorus and potassium fertilizers), on the assemblage of soil nematodes during the growing period of peanut were investigated. Significant differences among the treatments were observed for total nematode abundance, trophic groups and ecological indices (P < 0.01). The total nematode abundance decreased in the order of PK > NPKCaS > NPK > NP > NK. The total number of nematodes was significantly higher in NPKCaS and PK than in NPK, NP and NK except in May. Plant parasitic nematodes were the dominant trophic group in all treatments excepted in NPKCaS, and their proportion ranged between 38% and 65%. The dominant trophic group in NPKCaS was bacterivores and represented 42.1%. Furthermore, the higher values of maturity index, Wasilewska index and structure index in NPKCaS indicated that the combined application of NPK and gypsum could remarkably relieve soil acidification, resulting in a more mature and stable soil food web structure. While, that of the NK had the opposite effect. In conclusion, our study suggested that the application of both gypsum and phosphate is an effective practice to improve soil quality. Moreover, the analysis of nematode assemblage is relevant to reflect the impact of different inorganic fertilizer on the red soil ecosystem. PMID:25509090

  1. Nitrogen Turnover Processes in Low Temperatures in an Agricultural Peat Soil

    NASA Astrophysics Data System (ADS)

    Silvennoinen, H. M.; Hämäläinen, R.; Koponen, H. T.; Martikainen, P. J.

    2009-12-01

    Nitrogen (N) cycling in agricultural soils has a key impact on the environment. Agricultural ecosystems are the most important sources of nitrous oxide (N2O), an important greenhouse gas, to the atmosphere. Additionally N fertilizers used to improve plant growth lead to enhanced N leaching and thereby to eutrophication of surrounding aquatic ecosystems. Microbial processes are normally enhanced by increase in temperature. Several recent studies have shown that although N2O emissions from agricultural soils are of microbiological origin, produced mainly in microbial reduction of nitrate (NO3-) via nitric oxide (NO) and N2O to molecular nitrogen (N2) (denitrification), the temperature response of N2O emissions is greatly variable and there is a lot of evidence of high emissions during cold periods (Koponen et al. 2006). Denitrification is, however, regulated by availability of inorganic N and therefore dependant not only on N fertilization but also on N turnover processes in soil. These processes include mineralization of organic N to ammonium (NH4+), oxidation of NH4+ to nitrite and NO3- (nitrification). These processes and their regulation especially in low temperatures are yet poorly understood. In this experiment, gross rates of N mineralization and nitrification and carbon dioxide production were studied in various temperatures ranging from -1.5 to 15 °C. Soil samples were taken from grassland on peat soil in Southern Finland (60o49’N, 23o30’E) on September 8th 2008 from depths of 0-10 cm. Temperature responses of N gross mineralization and nitrification and of microbial respiration were measured in a laboratory experiment. The incubation temperatures used for experiments were 15, 5, 2.5, 1.5, 0.5, 0, -0.5 and -1.5 °C. After 7 d temperature-specific incubation, gross rates of N mineralization and nitrification were determined with pool dilution technique in a 24 h incubation experiment. This study showed that N turnover processes in agricultural peat soil exhibit temperature anomalies. Carbon dioxide production decreased linearly with decrease in temperature, while gross nitrification and mineralization rates showed high variability in low temperatures and showed no significant differences between studied temperatures. References: Koponen HT , Duran CE, Maljanen M, Hytönen J, Martikainen PJ. 2006. Temperature responses of NO and N2O emissions from boreal organic soil. Soil Biology & Biogeochemistry 38, 1779-1787.

  2. Transfer of radioactive caesium from soil to vegetation and comparison with potassium in upland grasslands.

    PubMed

    Coughtrey, P J; Kirton, J A; Mitchell, N G; Morris, C

    1989-01-01

    The distribution and transfer of caesium and potassium between soils and vegetation has been investigated by field sampling and experimental studies on soils and vegetation typical of upland grassland in north west England. Total (137)Cs content to a depth of 0.05 m below root matt ranged from 13 000 to 18 000 Bq m(-2). This caesium content derives from three sources: the Windscale accident of 1957, weapons-testing fallout which peaked in the early 1960s, and the Chernobyl accident in May 1986. From 2200 to 6200 Bq m(-2) is attributed to the first two sources, and the remainder to Chernobyl. In December 1986, 23-78% of pre-Chernobyl (137)Cs was associated with soil underlying root matt and 0.5-5.5% was associated with vegetation. Plant/soil concentration ratios for pre-Chernobyl (137)Cs were in the range 0.5-6.5, the lowest values being associated with patches of Festuca/Agrostis turf. At the same time, 4-19% of (137)Cs deposited from Chernobyl was associated with vegetation, although higher values appeared in conjunction with the moss, Polytrichum commune. Corresponding total potassium contents were in the range 9.6-22 mg m(-2) to 0.05 m soil depth. Lower values were found at the wetter sites where, on average, 5.7% of the total potassium was present in vegetation. At drier sites the potassium content was higher and, on average, 8.9% was present in vegetation. Plant/soil concentration ratios ranged from 2.2 to 9.2. During accelerated growth of vegetation, on monoliths in glasshouse conditions over the winter of 1986/87, (137)Cs was transferred from soil and root matt to new growth, such that concentrations in fresh growth were similar to or higher than those observed in the field during December 1986. Removal of caesium by successive cuts resulted in up to 25% of the original estimated total being removed over a 240 day period. Increased concentrations coincided with the emergence of Carex sp. and Trichophorum caespitosum, as well as the development of Agrostis sp. and Festuca ovina. Observed Cs/K discrimination ratios, particularly for (137)Cs deposited from Chernobyl, were higher than previously reported in the literature. The experimental results were confirmed by field observations during spring 1987 and it is concluded that caesium deposited as a result of the Chernobyl accident will continue to be recycled in organic and low potassium soils. PMID:15092335

  3. Soil-to-soybean transfer of (99)Tc and its underground distribution in differently contaminated upland soils.

    PubMed

    Choi, Yong-Ho; Lim, Kwang-Muk; Jun, In; Kim, Byung-Ho; Keum, Dong-Kwon; Kim, In-Gyu

    2014-06-01

    Pot experiments were performed in a greenhouse to investigate the soil-to-soybean transfer of (99)Tc in two different upland soils labeled with (99)TcO4(-) in two contrasting ways. One was to mix the soil with a (99)TcO4(-) solution 26 d before sowing (pre-sowing deposition: PSD), and the other was to apply the solution onto the soil surface 44 d after sowing (growing-period deposition: GPD). The soil-to-plant transfer was quantified with the transfer factor (TF, ratio of the plant concentration to the average of at-planting and at-harvest soil concentrations) or the aggregated transfer factor (TFag, ratio of the plant concentration to the deposition density). For both the depositions, the transfer of (99)Tc to aerial parts decreased in the order of leaf > stem > pod > seed. TF values (dimensionless) from the PSD were 0.22 and 0.27 (no statistically significant difference) for mature dry seeds in the respective soils, whereas a 600-fold higher value occurred for dry leaves. The post-harvest concentrations of the PSD (99)Tc in the top 20 cm soils as a whole were about half the initial concentrations. Around 25% of the total applied activity remained in the GPD soils after the harvest. The post-harvest depth profiles of the GPD (99)Tc in the two soils showed similar patterns of logarithmic activity decrease with increasing soil depths. Only 1.5-4.3% of the total applied activity was removed through the harvested biomass (seeds, pods and stems), and it was estimated that a great part of the total pant uptake returned to the soil through the fallen leaves. TFag values (m(2) kg(-1)) were about 2-4 times higher for the GPD than for the PSD. This finding and generally high root uptake of Tc may indicate that the use of empirical deposition time-dependent TFag data is particularly important for predicting the plant concentrations of Tc after its growing-period deposition. PMID:24556176

  4. Use of Computer-Aided Tomography (CT) Imaging for Quantifying Coarse Roots, Rhizomes, Peat, and Particle Densities in Marsh Soils

    EPA Science Inventory

    Computer-aided Tomography (CT) imaging was utilized to quantify wet mass of coarse roots, rhizomes, and peat in cores collected from organic-rich (Jamaica Bay, NY) and mineral (North Inlet, SC) Spartina alterniflora soils. Calibration rods composed of materials with standard dens...

  5. CARBON MONOXIDE FLUXES OF DIFFERENT SOIL LAYERS IN UPLAND CANADIAN BOREAL FORESTS

    EPA Science Inventory

    Dark or low-light carbon monoxide fluxes at upland Canadian boreal forest sites were measured on-site with static chambers and with a laboratory incubation technique using cores from different depths at the same sites. Three different upland black spruce sites, burned in 1987,199...

  6. pp iii Transport of lead and diesel fuel through a peat soil near Juneau, AK: a pilot study

    NASA Astrophysics Data System (ADS)

    Deiss, Julian; Byers, Carl; Clover, Dave; D'Amore, Dave; Love, Alan; Menzies, Malcolm A.; Powell, Jim; Todd Walter, M.

    2004-10-01

    A set of peat column experiments was used to determine the transport potential of lead (Pb) and diesel range organics (DRO) in palustrine slope wetlands near Juneau, AK. This project is important to southeast Alaskan communities because limited land resources are forcing development of regional wetlands. This study was instigated by concerns that proposed modifications to a nearby rifle range using DRO-contaminated soil posed a potential risk to an anadromous fish-bearing stream 250 m from the site. Three pairs of peat columns were extracted from the rifle range for analysis, one pair along and two pairs across the natural bedding planes of the soil. One column in each pair was spiked with Pb and DRO and the other was used as a control. Approximately 1-year worth of water (171 cm) was passed through each column and leachate was collected at regular intervals. The results showed that substantial DRO transport only occurred along the bedding planes. Leads was surprisingly mobile, both along and across the bedding planes with estimated soil-water partition coefficients several orders of magnitude lower than commonly published values, probably because the peat was heavily Pb-loaded by lead from bullets and because the peat's acidic, organic-rich environment enhanced Pb mobility. The chemical outflow behavior agreed with a simple macropore transport model. These results underscore the need for caution when developing regional wetlands.

  7. Time-scales of hydrological forcing on the geochemistry and bacterial community structure of temperate peat soils

    PubMed Central

    Nunes, Flavia L. D.; Aquilina, Luc; de Ridder, Jo; Francez, André-Jean; Quaiser, Achim; Caudal, Jean-Pierre; Vandenkoornhuyse, Philippe; Dufresne, Alexis

    2015-01-01

    Peatlands are an important global carbon reservoir. The continued accumulation of carbon in peatlands depends on the persistence of anoxic conditions, in part induced by water saturation, which prevents oxidation of organic matter, and slows down decomposition. Here we investigate how and over what time scales the hydrological regime impacts the geochemistry and the bacterial community structure of temperate peat soils. Peat cores from two sites having contrasting groundwater budgets were subjected to four controlled drought-rewetting cycles. Pore water geochemistry and metagenomic profiling of bacterial communities showed that frequent water table drawdown induced lower concentrations of dissolved carbon, higher concentrations of sulfate and iron and reduced bacterial richness and diversity in the peat soil and water. Short-term drought cycles (3–9 day frequency) resulted in different communities from continuously saturated environments. Furthermore, the site that has more frequently experienced water table drawdown during the last two decades presented the most striking shifts in bacterial community structure, altering biogeochemical functioning of peat soils. Our results suggest that the increase in frequency and duration of drought conditions under changing climatic conditions or water resource use can induce profound changes in bacterial communities, with potentially severe consequences for carbon storage in temperate peatlands. PMID:26440376

  8. Time-scales of hydrological forcing on the geochemistry and bacterial community structure of temperate peat soils

    NASA Astrophysics Data System (ADS)

    Nunes, Flavia L. D.; Aquilina, Luc; De Ridder, Jo; Francez, André-Jean; Quaiser, Achim; Caudal, Jean-Pierre; Vandenkoornhuyse, Philippe; Dufresne, Alexis

    2015-10-01

    Peatlands are an important global carbon reservoir. The continued accumulation of carbon in peatlands depends on the persistence of anoxic conditions, in part induced by water saturation, which prevents oxidation of organic matter, and slows down decomposition. Here we investigate how and over what time scales the hydrological regime impacts the geochemistry and the bacterial community structure of temperate peat soils. Peat cores from two sites having contrasting groundwater budgets were subjected to four controlled drought-rewetting cycles. Pore water geochemistry and metagenomic profiling of bacterial communities showed that frequent water table drawdown induced lower concentrations of dissolved carbon, higher concentrations of sulfate and iron and reduced bacterial richness and diversity in the peat soil and water. Short-term drought cycles (3-9 day frequency) resulted in different communities from continuously saturated environments. Furthermore, the site that has more frequently experienced water table drawdown during the last two decades presented the most striking shifts in bacterial community structure, altering biogeochemical functioning of peat soils. Our results suggest that the increase in frequency and duration of drought conditions under changing climatic conditions or water resource use can induce profound changes in bacterial communities, with potentially severe consequences for carbon storage in temperate peatlands.

  9. Secondary successions of biota in oil-polluted peat soil upon different biological remediation methods

    NASA Astrophysics Data System (ADS)

    Melekhina, E. N.; Markarova, M. Yu.; Shchemelinina, T. N.; Anchugova, E. M.; Kanev, V. A.

    2015-06-01

    The effects of different bioremediation methods on restoration of the oil-polluted peat soil (Histosol) in the northernmost taiga subzone of European Russia was studied. The population dynamics of microorganisms belonging to different trophic groups (hydrocarbon-oxidizing, ammonifying, nitrifying, and oligonitrophilic) were analyzed together with data on the soil enzyme (catalase and dehydrogenase) activities, population densities of soil microfauna groups, their structures, and states of phytocenoses during a sevenyear-long succession. The remediation with biopreparations Roder composed of oil-oxidizing microorganisms-Roder with Rhodococcus rubber and R. erythropolis and Universal with Rhodotorula glutinis and Rhodococcus sp.-was more efficient than the agrochemical and technical remediation. It was concluded that the biopreparations activate microbiological oil destruction, thereby accelerating restoration succession of phytocenosis and zoocenosis. The succession of dominant microfauna groups was observed: the dipteran larvae and Mesostigmata mites predominant at the early stages were replaced by collembolans at later stages. The pioneer oribatid mite species were Tectocepheus velatus, Oppiella nova, Liochthonius sellnicki, Oribatula tibialis, and Eupelops sp.

  10. Water-soluble organic acids in cryomorphic peat soils of the southeastern Bol'shezemel'skaya tundra

    NASA Astrophysics Data System (ADS)

    Shamrikova, E. V.; Kaverin, D. A.; Pastukhov, A. V.; Lapteva, E. M.; Kubik, O. S.; Punegov, V. V.

    2015-03-01

    The composition of the water extracts, the pH, and the weight concentrations of the total organic carbon and low-molecular-weight organic acids in seasonally thawed and perennially frozen horizons of cryomorphic peat soils have been determined. The quantitative analysis of the acids converted to trimethylsilyl derivatives has been performed by gas chromatography and chromato-mass spectroscopy. Hydroxypropanoic, propanoic, and hydroxyethanoic acids are the prevailing acids (30-50, 10-20, and 10% of the total acids, respectively). Malic, glyceric, hexadionic, trihydroxybutanoic, ribonic, and other acids have also been detected. It has been shown that the differences in the genesis of the peat deposits significantly affect the composition and content of water-soluble organic compounds in soils on the soil-profile and landscape levels.

  11. 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.; Kristijono, A.; Sudiana, N.; Nurjaman, D.; Darusman, T.

    2015-01-01

    Current estimates of carbon (C) storage in peatland systems worldwide indicate tropical peatlands comprise about 15% of the global peat carbon pool. Such estimates are uncertain due to data gaps regarding organic peat soil thickness and C content. Indonesian peatlands are considered the largest pool of tropical peat carbon (C), accounting for an estimated 65% of all tropical peat while being the largest source of carbon dioxide emissions from degrading peat worldwide, posing a major concern regarding long-term sources of greenhouse gases to the atmosphere. We combined a set of indirect geophysical methods (ground penetrating radar, GPR, and electrical resistivity imaging, ERI) with direct observations from core samples (including C analysis) to better understand peatland thickness in West Kalimantan (Indonesia) and determine how geophysical imaging may enhance traditional coring methods for estimating C storage in peatland systems. Peatland thicknesses estimated from GPR and ERI and confirmed by coring indicated variation by less than 3% even for small peat-mineral soil interface gradients (i.e. below 0.02°). The geophysical data also provide information on peat matrix attributes such as thickness of organomineral horizons between peat and underlying substrate, the presence of wood layers, buttressed trees and soil type. These attributes could further constrain quantification of C content and aid responsible peatland management in Indonesia.

  12. Thermodynamics of peat-, plant-, and soil-derived humic acid sorption on kaolinite.

    PubMed

    Ghabbour, Elham A; Davies, Geoffrey; Goodwillie, Melissa E; O'Donaughy, Kelly; Smith, Tammy L

    2004-06-15

    Humic acids (HAs) form coatings on clays and minerals that can play an important role in nutrient and contaminant migration in soil and water. Humic acid-clay mineral interactions are known to be affected by pH and ionic strength, but little attention has been paid to the effects of temperature. In this paper we report the stoichiometry and thermodynamics of interactions of aqueous HAs (isolated from two peats, two soils and a marine alga with a method that removes lipids) with kaolinite clay, Al2Si2O5(OH)4, at seven temperatures from 5.0 to 35.0 degrees C in 0.05 M NaCl at pH 3.5. All the sorption isotherms exhibit consecutive steps ascribed to HA monolayer and bilayer formation, respectively. Site capacity comparisons suggest different HA molecular conformations on kaolinite. Linearly correlated enthalpy and entropy changes for HA sorption point to the importance of hydration and dehydration in the sorption mechanism. PMID:15260333

  13. Function of peatland located on secondary transformed peat-moorsh soils on groundwater purification processes and the elution of soil organic matter

    NASA Astrophysics Data System (ADS)

    Szczepa?ski, M.; Szajdak, L.; Bogacz, A.

    2009-04-01

    The investigation of peatland is used to show the water quality functioning with respect to different forms of nitrogen and carbon. The purification of ground water by the transect of 4.5 km long consisting organic soils (peat-moorsh soils) was estimated. This transect is located in the Agroecological Landscape Park in Turew, 40 km South-West of Poznan, West Polish Lowland. There is this transect along Wysko? ditch. pH, the contents of total and dissolved organic carbon, total nitrogen, N-NO3-, N-NH4+ was measured. Additionally C/N factors of peats were estimated. The investigation has shown the impact of the peatland located on the secondary transformed peat - moorsh soils on the lowering of total nitrogen, ammonium, and nitrates as well as total and dissolved organic carbon in ground water. Peat-moorsh soils were described and classified according to Polish hydrogenic soil classification and World Reference Base Soil Notation. There are these investigated points along to Wyskoc ditch. Two times a month during entire vegetation season the following material was taken from four chosen sites marked as Zbechy, Bridge, Shelterbelt and Hirudo: samples of peat, from the depth of 0-20 cm, samples of water from the ditch, samples of ground water from wells established for this investigation. Samples of peat-moorsh soils were collected at the depth 0-20 cm. Soils were sampled two times a month from 10 sites of each site. Samples were air dried and crushed to pass a 1 mm-mesh sieve. These 10 sub-samples were mixed for the reason of preparing a "mean sample", which used for the determination of pH (in 1M KCl), dissolved organic carbon (DOC), total organic carbon (TOC), total nitrogen (Ntotal), and N-NO3- as well as N-NH4+. In water from Wysko? ditch pH, Ntotal, N-NO3-, N-NH4+, DTC (dissolved total carbon) and DOC (dissolved organic carbon) was measured. Ground water samples were collected from four wells established for this investigation. The water was filtered by the middle velocity separation and pH, N-total, N-NO3-, N-NH4+, DTC (dissolved total carbon) and DOC (dissolved organic carbon) ware measured. Peatland located on the secondary transformed peat - moorsh soils has revealed the lowering in ground water: nitrates 38.5%, N-organic 10%, N-total 24.5%, ammonium 38.7%, dissolved total carbon 33.1%, dissolved total inorganic carbon 10%, and dissolved organic carbon 57.5%. The dissolution of soil organic matter from peat-moorsh soils in broad range of pH and ionic strength was investigated. The rates of the reaction were calculated from the kinetics of first order reaction model. The investigations have shown the impact of the properties of secondary transformed peat-moorsh soils on the rates of the dissolution of organic matter.

  14. Hydrochemical modelling of the retention and transport of metallic radionuclides in the soils of an upland catchment.

    PubMed

    Tipping, E

    1996-01-01

    The CHemistry of the Uplands Model (CHUM) describes the transport of chemicals through upland catchments with acid, organic-rich soils, by a combination of sub-models for equilibrium soil chemistry, hydrology, weathering, and nitrogen cycling. CHUM was used to simulate the retention and transport of metallic radionuclides (Co, Sr, Cs, UO(2), U(IV), Th, Am), in the soils of a small catchment in Cumbria, UK, for 2 years after their atmospheric deposition in a single hypothetical precipitation event. Export of radionuclides to streamwater is calculated to occur most readily following deposition of the dissolved elements at high water saturation of the catchment, when little incoming rainwater is required to make up the small moisture deficit of the organic surface horizon, and solutes can move to greater depths in the soil profile. Deposition when the catchment is drier, or of particulate radionuclides, leads to stronger retention. Radionuclide retention or transport depends on the strength of chemical interaction with the solid phases of the different soil horizons; this varies among the elements, and also with oxidation state, U(IV) species being more strongly retained than UO(2). For purely organic soils, the least strongly retained radionuclide is Cs, but the presence in the mineral soil horizon of small amounts of clay mineral with high selectivity towards Cs can markedly increase with high selectivity towards Cs can markedly increase its retention. For the actinides, binding by dissolved organic matter is important; for example, the rate of transport of Th to the stream is increased by more than two orders of magnitude by complexation with dissolved fulvic acid. The model assumptions suggest that, in the longer term, losses from the catchment of Co, Sr and Cs would take place on a time-scale of decades, whereas the actinides would be much more persistent. PMID:15093497

  15. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

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

  17. Dactylosporangium sucinum sp. nov., isolated from Thai peat swamp forest soil.

    PubMed

    Phongsopitanun, Wongsakorn; Kudo, Takuji; Ohkuma, Moriya; Suwanborirux, Khanit; Tanasupawat, Somboon

    2015-06-01

    The actinomycete strain RY35-23(T) was isolated from peat swamp forest soil in Thailand. The taxonomic position of this strain was determined using polyphasic approach. Strain RY35-23(T) showed typical morphology and chemical properties similar to the members in the genus Dactylosporangium. On the basis of 16S ribosomal RNA gene analysis, this strain was closely related to Dactylosporangium fulvum JCM 5631(T) (98.94%), D. roseum JCM 3364(T) (98.87%) and D. darangshiense JCM 17441(T) (98.86%). The DNA-DNA relatedness between strain RY35-23(T) and its closely related species was lower than 70%, the cutoff level for assigning strains to the same species. On the basis of these results mentioned, the strain RY35-23(T) could be distinguished from its closely related type strains and represents a novel species of the genus Dactylosporangium, for which the name Dactylosporangium sucinum (type strain RY35-23(T)=JCM 19831(T)=TISTR 2212(T)=PCU 333(T)) is proposed. PMID:25605042

  18. Effect of converting wetland forest to sago palm plantations on methane gas flux and organic carbon dynamics in tropical peat soil

    NASA Astrophysics Data System (ADS)

    Inubushi, K.; Hadi, A.; Okazaki, M.; Yonebayashi, K.

    1998-10-01

    The effect of changing wetland forest to sago palm plantations on methane gas flux and organic carbon dynamics in tropical peat soil was studied in the field and the laboratory using soil samples from the Peat Research Station, Sarawak, Malaysia. A small amount of methane was released from the soil surface of both the forest and plantation field, with no significant difference between the two sites (1·1+/-0·61 and 1·39+/-0·82 mg CH4 m-2 hr-1, respectively); thus, the amount of methane emission from the total area of tropical peat soil was estimated, preliminarily, as 2·43 Tg yr-1, contributing 0·45% of the total global methane emission and 2·1% of methane emissions from global natural wetland. However, large amounts of methane were accumulated in the deeper soil layers. Sago palm contained much less carbon as biomass, but lost more as the carbon dissolved in groundwater. Laboratory experiments showed that incorporation of rice straw into tropical peat soil increased methane formation significantly. Conversely, ammonium sulfate suppressed methane formation in tropical peat soil.

  19. Restoration of Upland Hardwood Tree Species on the Formerly Cultivated Soils in the Coastal Plain of South Carolina

    SciTech Connect

    Jones, R.H.; Waldrop, T.A.

    2001-08-03

    The authors studied various approaches to restore upland hardwood species to formerly cultivated soils at the SRS. Studies with direct seedling were largely a failure and resulted in very low rates of establishment. Failure was a result of predation and drought. Growth and survival of planted oaks, dogwood and pine did not vary between hardwood overstory and pine overstory conditions. Soil trenching in a forty year old loblolly stand demonstrated dramatic increases in growth of planted oaks and dogwood. When compared, survival is similar if not slightly better when seedlings are planted in the understory of canopies vs. clearcuts. However, growth is better in recent clearcuts for dogwood and white oaks. Hickory does better underplanted.

  20. 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 ?13C 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.

  1. The role of mineralization of the organic matter of soddy-podzolic and peat bog soils in the accumulation of 137Cs by plants

    NASA Astrophysics Data System (ADS)

    Tulina, A. S.; Semenov, V. M.; Tsybul'Ka, N. N.; Shapsheeva, T. P.; Zaitsev, A. A.; Arastovich, T. V.

    2010-10-01

    The role of mineralization of soil organic matter (SOM) in the mobilization of 137Cs was estimated on the basis of data on the biokinetic fractionation of the organic matter of soddy-podzolic sandy-loam and peat bog soils and on the coefficients of the soil-to-plant transfer of radiocesium under field conditions. The peat bog soils were richer than the soddy-podzolic soils in the total organic carbon (by 7.9-23.8 times), the potentially mineralizable carbon (by 2.4-6.5 times), and the carbon of the microbial biomass (by 2.9-4.6 times). The agricultural use of the soddy-podzolic and peat bog soils led to a decrease in the SOM mineralization capacity by 1.1-1.8 and 1.4-2.0 times, respectively. Simultaneously, the portions of the easily, moderately, and difficultly mineralizable fraction of the SOM active pool changed. The coefficients of the 137Cs transfer from the peat bog soils to plants were 3.3-17.6 times higher than those for the soddy-podzolic soils. The content of 137Cs in plants grown on the peat bog soils was 2-65 times higher than that in the mobile (salt-extractable) soil pool by the beginning of the growing season. Strong positive linear correlations were found between the coefficients of the soil-to-plant transfer of 137Cs and the total content of the SOM, the content of the microbial biomass, the content of the potentially mineralizable carbon, and the intensity of its mineralization. It was concluded that the decisive factors controlling the intensity of the 137Cs transfer from mineral and organic soils into plants are the SOM content and its mineralization potential. The mineralization of the SOM is accompanied by the release of both 137Cs and mineral nitrogen; the latter facilitates the transfer of radiocesium into plants.

  2. Ecological Framework For Assessing Changes In Soil Water And Carbon In Response To Degrading Permafrost

    NASA Astrophysics Data System (ADS)

    Jorgenson, T.

    2011-12-01

    The response of soil water and carbon to permafrost degradation differs greatly across the varied terrain of boreal Alaska. Responses can be broadly partitioned among rocky uplands on ice poor bedrock and colluvial deposits, loamy uplands on extremely ice rich Pleistocene loess, sandy lowlands on sand sheets, and peaty lowlands on abandoned floodplains, retransported deposits on lower slopes, and lowland loess. On rocky uplands, soil carbon and water stocks are low and most carbon and water is lost after fire and subsequent thawing of permafrost. On loamy uplands, much of the soil carbon is lost after fire, but soils remain saturated after thawing of the ice rich intermediate layer. Deeper permafrost is resilient. On sandy lowlands, forest soils have low carbon stocks and water contents, in contrast to the high carbon stocks in perched lakes maintained by permafrost. Thawing of permafrost leads to drying of forest soils and draining of lakes, exposing soil carbon to aerobic conditions for decomposition. Peaty lowlands have thick peat deposits associated with black spruce permafrost plateaus and unfrozen collapse-scar bogs and fens. Thawing leads to 2 to 4 m of collapse and large loss of ice.Formation of bogs impounds water in depressions and leads to rapid accumulation of bog peat. Thawing of forest peat also leads to substantial decomposition of old forest peat.

  3. Effect of soil texture, tailwater height, and pore-water pressure on the morphodynamics of migrating headcuts in upland concentrated flows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rill and gully erosion in upland and agricultural areas can result in significant soil degradation worldwide, and headcuts are the primary mechanism by which this landscape dissection occurs. Experiments were conducted to further examine the morphodynamic behavior of actively migrating headcuts in u...

  4. Exploring the potential of the permanganate oxidation method as a tool to monitor soil quality in agricultural upland systems of Southeast Asia

    NASA Astrophysics Data System (ADS)

    Hepp, Catherine M.; Bruun, Thilde Bech; de Neergaard, Andreas

    2014-05-01

    The transition to more intensified upland systems is having an impact on the soil quality, defined as the ability of a soil to both provide and maintain essential services to an ecosystem. As many tropical upland soils are inherently low in quality, it is essential that impacts be monitored. Soil quality is assessed by using a combination of parameters that serve as indicators and cover the soil chemical, biological and physical properties. An ideal indicator should be sensitive to changes in the environment and management practices and should be widely accessible, meaning low resource requirement (i.e. time and equipment). Total organic carbon (TOC) content is a commonly used indicator of soil quality as it is linked to many soil functions and processes; however analysis is costly and requires access to advanced instrumental facilities, rendering it unsuited for many developing countries. An alternative indicator is the soil fraction dominated by easily decomposable carbon; this may be measured by treating soil samples with 0.2M potassium permanganate (KMnO4), an oxidizing agent which is thought to mimic the enzymes released by the soil microbial community. The advantage of this method is that it is accessible: it is fast, requires little resource input and is field appropriate. There is no consensus however as to which soil carbon fraction the method targets. Furthermore Skjemstad et al. (2006) has indicated that KMnO4 may oxidise charcoal, a component of the non-labile carbon pool; this has implications for the suitability of the method when used for soils of shifting cultivation systems. The purpose of this study was to investigate the potential of permanganate oxidizable carbon (Pox C) as a reliable indicator of soil quality in agricultural upland systems in Northern Lao PDR. Focus was placed on the relations between Pox C and other soil quality parameters (bulk density, pH, CEC, TOC, total N, exchangeable K, plant available P) and upland rice yields. The ability of KMnO4 to oxidize charcoal was also a focus however, as the study is still in its initial stage, no results can be discussed. Volumetric soil samples (at the surface and at 10 cm) and upland rice yield measurements were taken from three fields with three plots that were previously left fallow for five years (n=9; soil n=81). Pearson's Correlation test and Stepwise Regression analysis was done using SPSS v 16.0 for Windows. Results show that Pox C is significantly correlated to the measured soil parameters in a manner similar to TOC. Both are positively correlated to the soil nutrients: Total N %, P Avail and K Exch; Pox C however had a stronger correlation to K Exch than TOC. This affirms the important role of Pox C in soil processes in the biological, chemical and physical spheres. Furthermore, the regression analysis identified Pox C as an influencing factor for the variations seen in upland rice yields. It is concluded that Pox C is a suitable indicator for soil quality and may be useful in monitoring changes in the soil quality of agricultural upland systems.

  5. SOIL AMENDMENT WITH DIFFERENT PEAT MOSSES AFFECTS VA MYCORRHIZAE ON ONION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Formation of VA mycorrhizae in soilless potting mixes that usually contain some proportion of peat moss has been inhibited in many cases. The cause o the inhibition has been reported to be high phosphorus (P) content in the media that suppresses spread of the fungal symbiont in the root tissue. How...

  6. Soil evolution and climate dynamics in dry steppes of the Privolzhskaya Upland during the last 3500 years

    NASA Astrophysics Data System (ADS)

    Demkin, V. A.; Demkina, T. S.; Khomutova, T. E.; El'tsov, M. V.

    2012-12-01

    The investigation of paleosols of different ages buried under archaeological monuments of the Bronze (16th-15th centuries BC), Early Iron (2nd-3rd centuries AD), and Medieval (14th century AD) ages demonstrated that the evolution of chestnut soils and solonetzes in the dry steppes of the southern part of the Privolzhskaya Upland during the past 3500 years manifested itself at the level of the genus and species characteristics of the soils, such as the degree of the solonetzicity, the humus content, and the content and composition of the soluble salts. The revealed regularities of the variations of the morphological, chemical, and microbiological soil properties in time allowed reconstructing the secular dynamics of the climatic humidity in the region. It was found that the humidization of the climate with a decrease in the degree of the climatic continentality took place in the middle of the second millennium BC. The Late Sarmatian Time (2nd-3rd centuries AD) was characterized by arid climatic conditions, whereas the Golden Horde time (13th-14th centuries AD) was marked by the general humidization of the climate. A gradual aridization of the climate began in the second half of the 14th century and continued in the 15th century AD.

  7. 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.

  8. Catchment disturbance and stream metabolism: patterns in ecosystem respiration and gross primary production along a gradient of upland soil and vegetation disturbance

    SciTech Connect

    Houser, Jeffrey N

    2005-01-01

    Catchment characteristics determine the inputs of sediments and nutrients to streams. As a result, natural or anthropogenic disturbance of upland soil and vegetation can affect instream processes. The Fort Benning Military Installation (near Columbus, Georgia) exhibits a wide range of upland disturbance levels because of spatial variability in the intensity of military training. This gradient of disturbance was used to investigate the effect of upland soil and vegetation disturbance on rates of stream metabolism (ecosystem respiration rate [ER] and gross primary production rate [GPP]). Stream metabolism was measured using an open-system, single-station approach. All streams were net heterotrophic during all seasons. ER was highest in winter and spring and lowest in summer and autumn. ER was negatively correlated with catchment disturbance level in winter, spring, and summer, but not in autumn. ER was positively correlated with abundance of coarse woody debris, but not significantly related to % benthic organic matter. GPP was low in all streams and generally not significantly correlated with disturbance level. Our results suggest that the generally intact riparian zones of these streams were not sufficient to protect them from the effect of upland disturbance, and they emphasize the role of the entire catchment in determining stream structure and function.

  9. Catchment disturbance and stream metabolism: Patterns in ecosystem respiration and gross primary production along a gradient of upland soil and vegetation disturbance

    USGS Publications Warehouse

    Houser, J.N.; Mulholland, P.J.; Maloney, K.O.

    2005-01-01

    Catchment characteristics determine the inputs of sediments and nutrients to streams. As a result, natural or anthropogenic disturbance of upland soil and vegetation can affect instream processes. The Fort Benning Military Installation (near Columbus, Georgia) exhibits a wide range of upland disturbance levels because of spatial variability in the intensity of military training. This gradient of disturbance was used to investigate the effect of upland soil and vegetation disturbance on rates of stream metabolism (ecosystem respiration rate [ER] and gross primary production rate [GPP]). Stream metabolism was measured using an open-system, single-station approach. All streams were net heterotrophic during all seasons. ER was highest in winter and spring and lowest in summer and autumn. ER was negatively correlated with catchment disturbance level in winter, spring, and summer, but not in autumn. ER was positively correlated with abundance of coarse woody debris, but not significantly related to % benthic organic matter. GPP was low in all streams and generally not significantly correlated with disturbance level. Our results suggest that the generally intact riparian zones of these streams were not sufficient to protect them from the effect of upland disturbance, and they emphasize the role of the entire catchment in determining stream structure and function. ?? 2005 by The North American Benthological Society.

  10. The sensitivity of peat soil and peatland vegetation to drought: release of dissolved organic carbon (DOC) on rewetting

    NASA Astrophysics Data System (ADS)

    Ritson, Jonathan; Graham, Nigel; Templeton, Michael; Freeman, Christopher; Clark, Joanna

    2015-04-01

    Organic rich peat soils are a major store of carbon worldwide. Their existence is predicated on high year-round water tables which create an anoxic environment, thus limiting decay, and also to the recalcitrance of plant litter (dead plant material) commonly found in peatland areas. Climate change threatens the stability of peat soils by altering the biogeochemical cycles which control plant decay, lowering water tables so that oxic degradation can occur and by changing habitat niches such that less recalcitrant species can thrive in peatlands. One of the major fluxes of carbon from peatlands is through dissolved organic carbon (DOC) in surface waters. As peatland areas in the UK are often used as source waters for drinking water supply this presents a problem to water utilities as DOC must be effectively removed to limit colour, odour and the formation of potentially carcinogenic by-products on disinfection. Changes in catchment vegetation may occur due to climate change, nutrient deposition and changing bioclimatic envelopes. How different peatland vegetation contribute to DOC flux and how this may change in the future is therefore of interest. A six week laboratory simulation was performed on typical peatland litter (Sphagnum spp., Calluna vulgaris, Molinea caerulea, Juncus effusus) and a peat soil collected from Exmoor National Park, UK. The simulation monitored DOC flux from the decaying litter/soil and considered the impact of different drought severities using the 50th, 25th, 10th and 5th percentiles of the mean July/August monthly rainfall for Exmoor. On rewetting following the drought, all sources produced significantly different amounts of DOC (Tukey HSD p<0.05) in the order Molinia>Juncus>Calluna>Sphagnum>peat. The source also had a significant (ANOVA p<0.001) effect on coagulation removal efficiency, a typical method of removing DOC during drinking water treatment, with Juncus DOC proving the easiest to remove whilst Sphagnum DOC was the most difficult. Sphagnum DOC had the lowest ratio of humic-like to protein-like fluorescence, which is indicative of DOC which is poorly removed by coagulation. An interactive effect was noted between DOC source and the drought treatment which was explored further using a one-way ANOVA with a Holm-Šidák correction. This suggested peat will produce significantly more DOC when affected by drought (p=0.010), possibly explained by increased oxygenation engaging the 'enzymatic latch' mechanism. A similar analysis was performed on the interaction between drought and DOC source for the specific UV absorbance at 254nm (SUVA) value (a measure of aromaticity). This suggested that Molinea caerulea produces DOC of significantly (p=0.001) higher aromaticity following periods of drought. Comparisons between drought and DOC source factors suggest the source in more important than climatic conditions of decay which is consistent with our previously published findings. These results have implications for marginal peatlands which may be at risk from increased water table drawdown in the future as climate changes and where Molinea caerulea, typically a fen species, is encroaching on bog communities.

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

    USGS Publications Warehouse

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

    2000-01-01

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

  12. Time-lapse ground penetrating radar (GPR) measurements for exploring biogenic gas distribution and releases from peat soils in the Florida Everglades

    NASA Astrophysics Data System (ADS)

    Wright, W. J.; Comas, X.; Berber, M.

    2013-12-01

    Peat soils are known to release significant amounts of methane (CH4) and carbon dioxide (CO2) to the atmosphere. However, uncertainties still remain regarding the spatio-temporal distribution of gas accumulations and the triggering mechanisms of gas releasing events. Furthermore, most peatland gas dynamics research has historically been focused on high latitude peatlands, while recent works have suggested that gas production rates from low-latitude peat soils may be higher than those from colder climates. Ground penetrating radar (GPR) is a geophysical tool that has successfully been used in the past to non-invasively investigate the release of biogenic gasses from peat soils. This study is conducted in the Loxahatchee Impoundment Landscape Assessment (LILA), a hydrologically controlled, landscape scale (30 HA) model of the Florida Everglades. Here, temporal and spatial heterogeneity of gas releases from peat soil at the plot scale (<100 m2) are shown using a time series of three-dimensional (3D) GPR measurements. GPR data are supported by direct gas flux measurements using flux chambers combined with time-lapse photography, and surface deformation measurements using terrestrial LiDAR scanning and differential leveling.

  13. Comparing terrestrial laser scanning with ground and UAV-based imaging for national-level assessment of upland soil erosion

    NASA Astrophysics Data System (ADS)

    McShane, Gareth; Farrow, Luke; Morgan, David; Glendell, Miriam; James, Mike; Quinton, John; Evans, Martin; Anderson, Karen; Rawlins, Barry; Quine, Timothy; Debell, Leon; Benaud, Pia; Jones, Lee; Kirkham, Matthew; Lark, Murray; Rickson, Jane; Brazier, Richard

    2015-04-01

    Quantifying soil loss through erosion processes at a high resolution can be a time consuming and costly undertaking. In this pilot study 'a cost effective framework for monitoring soil erosion in England and Wales', funded by the UK Department for Environment, Food and Rural Affairs (Defra), we compare methods for collecting suitable topographic measurements via remote sensing. The aim is to enable efficient but detailed site-scale studies of erosion forms in inaccessible UK upland environments, to quantify dynamic processes, such as erosion and mass movement. The techniques assessed are terrestrial laser scanning (TLS), and unmanned aerial vehicle (UAV) photography and ground-based photography, both processed using structure-from-motion (SfM) 3D reconstruction software. Compared to other established techniques, such as expensive TLS, SfM offers a potentially low-cost alternative for the reconstruction of 3D high-resolution micro-topographic models from photographs taken with consumer grade cameras. However, whilst an increasing number of research papers examine the relative merits of these novel versus more established survey techniques, no study to date has compared both ground-based and aerial SfM photogrammetry with TLS scanning across a range of scales (from m2 to 16ha). The evaluation of these novel low cost techniques is particularly relevant in upland landscapes, where the remoteness and inaccessibility of field sites may render some of the more established survey techniques impractical. Volumetric estimates of soil loss are quantified using the digital surface models (DSMs) derived from the data from each technique and subtracted from a modelled pre-erosion surface. The results from each technique are compared. The UAV was able to capture information over a wide area, a range of altitudes and angles over the study area. Combined with automated SfM-based processing, this technique was able to produce rapid orthophotos to support ground-based data acquisition, as well as a DSM for volume loss measurement in larger features. However, the DSM of erosion features lacked the detail of those captured using the ground-based methods. Terrestrial laser scanning provided detailed, accurate, high density measurements of the ground surface over long (100s m) distances, but size and weight of the instrument made it difficult to use in mountainous environments. In addition, deriving a reliable bare-earth digital terrain model (DTM) from TLS was at times problematic due to the presence of tall shrubby vegetation. Ground-based photography produced comparable data sets to terrestrial laser scanning and was the most useful for characterising small and difficult to view features. The relative advantages, limitations and cost-effectiveness of each approach at 5 upland sites across the UK are discussed.

  14. PHYSICAL AND ANALYTICAL MODELING OF UPLAND SOIL EROSION DUE TO HEADCUT MIGRATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    On hillslopes and agricultural fields, discrete areas of intense, localized soil erosion commonly take place in the form of migrating headcuts. These erosional features significantly increase soil loss and landscape degradation, yet the unsteady, transient, and migratory habits of headcuts complica...

  15. ERODIBILITY OF A SOIL DRAINAGE SEQUENCE IN THE LOESS UPLANDS OF MISSISSIPPI

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The susceptibility of loess soils in the lower Mississippi to runoff and erosion losses varies as a function of landscape position and mapping units. This study was conducted to determine the effects of soil drainage on physical and chemical properties that influence erodibility through their contr...

  16. Soil-vegetation correlations in selected wetlands and uplands of North-Central Florida

    USGS Publications Warehouse

    Best, G. Ronnie; Wolfe, Charlotte; Segal, Debra S.

    1990-01-01

    Vegetation on four hydric and two nonhydric soils series in north-central Florida was sampled as part of a national study examining the correspondence between wetland vegetation and soils. The wetland character of the vegetation was estimated by weighted average calculations using published wetland indicator values for individual plant species. The weighted averages produced an ordering of plant communities in general agreement with the hydric character of the soils. However, the two nonhydric soils has weighted average scores slightly below 3, normally considered the lowest end of the range of nonhydric vegetation. There was no clear or consistent effect of fire management on the weighted average scores. Vegetation strata (herbaceous, low shrub, tall shrub, and trees) were generally similar in weighted average values, with the wettest of the hydric soils tending to be low in all strata and the nonhydric soils tending to be high in all strata. However, strata differed considerably in the specific values for a single soil and in the specific rank ordering of soils in different strata.

  17. Application of soil magnetometry on peat-bogs and soils in areas affected by historical and prehistoric ore mining and smelting.

    NASA Astrophysics Data System (ADS)

    Magiera, Tadeusz; Mendakiewicz, Maria; Szuszkiewicz, Marcin; Chrost, Leszak

    2015-04-01

    The valleys of upper Brynica and Sto?a located in northern part of Upper Silesia were areas of historical human activities since prehistoric times. Historically confirmed mining and smelting of iron, silver and lead ores on this areas has been dated back to early Middle Ages, however recently some geochemical and radiometric analyses suggest even prehistoric time of such activities. The aim of this study was to check if it is possible to find any magnetic signal suggesting such activities in peat-bogs and soils of this area. This magnetic properties would be a result of presence of historical Technogenic Magnetic Particles (TMPs) arisen during the primitive smelting processes in the past. Many different types of TMPs were separated from the depth of 15-30 cm of soil profiles and also were present in deeper parts of peat-bogs accompanied by fine charcoal particles. The peat-bog horizons dated by radiocarbon (C14) for 2000 BC were contaminated by some heavy metals (Cu, Zn, Cd, Ag, Pb, Mn, Fe, Sr, Sc) and slightly increased magnetic susceptibility signal was also observed. On the base of soil surface magnetic measurement using MS2D Bartington sensor complemented by magnetic gradiometer system Grad 601-02 for the deeper soil penetration, some local magnetic anomalies were detected. In areas of local 'hot spots', the vertical cores up to 30 cm in depth were collected using the HUMAX core sampler. Vertical distribution of magnetic susceptibility along the cores was measured in the laboratory using the MS2C Bartington core sensor. The core section with increased susceptibility values were analyzed and TMPs were separated using a hand magnet. The separation of fine fraction of TMPs was carried out in an ultrasonic bath from the fine soil material suspended in isopropanol to avoid their coagulation. Irregular ceramic particles, ash and ore particles, as well as strong magnetic particles of metallic iron; all with diameter up to 10 mm and almost regular shape and rounded edges were magnetically separated from the 15-30 cm of topsoil cores. In order to determinate the mineralogical composition of magnetic particles in soil samples a SEM-EDS technique was used. On the base of the magnetic prescreening the archeological excavations on the study area are planning.

  18. Paleoenvironmental reconstruction of the Brady Soil in the Nebraska loess uplands using biosilicate and bioturbation analyses

    E-print Network

    Woodburn, Terri Lee

    2014-12-31

    This dissertation takes a multiple-proxy approach to a paleoenvironmental reconstruction of the Holocene--Pleistocene Transition represented by the Brady Soil in the central Great Plains. To better understand this dynamic time of climate change...

  19. Peat surface GHG fluxes related to peat hydrology in various tropical peat land uses

    NASA Astrophysics Data System (ADS)

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

    2010-05-01

    It is generally accepted that the gradual increase in the mean temperature of the Earth's surface is primarily due to rising concentrations of greenhouse gases (GHG), especially carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) in the atmosphere. Tropical peatlands are an important component of the global peatland resource, contributing to terrestrial carbon storage in both their above-ground biomass (peat swamp forest) and underlying thick deposits of peat, which both participate soil-atmosphere carbon exchange processes. In their natural state, these forests have the ability to sequester carbon from the atmosphere during photosynthesis, retain this in plant biomass and store part of it in the peat. This process occurs mainly because of the frequent waterlogged condition of the peat, which reduces organic matter decomposition significantly and this causes the rate of organic matter production to exceed its breakdown. Peatland development, however, requires drainage, brings about changes in the vegetation type C-sequestration capacity and leads to changes in peat organic matter dynamics. Drainage promotes the depth of oxic conditions deeper in peat profile and thus speeds up peat stored organic matter mineralization. Aerobic conditions and high redox potentials created by drainage are known to favour microbial activity, which can enhance C and N losses by peat mineralization. Large areas of tropical peat have been drained, resulting in an abrupt and permanent shift in the ecosystem carbon balance from sink to source. Discussion of the current role of tropical peatlands in regional and global climate change processes is based mostly on circumstantial and secondary evidence, largely because total ecosystem carbon balance studies are very few and unsatisfactory. Peat surface GHG flux data are spatially very fragmented and have not usually been collected over entire diurnal or seasonal cycles. Interpretation of the impact of biophysical factors of tropical peat on tropical peat carbon dynamics is very difficult because of variations in environmental conditions (especially peat hydrology), peat and vegetation that are not collected systematically or reported adequately in studies. In this paper we (i.) compare the most important greenhouse gases, i.e. CO2, CH4, and N2O, related to peatland hydrology in typical land use types and peat drainage intensities, and (ii.) assess gaps existing in currently available GHG data collected from tropical peat in South-East Asia. Presented information is derived from our established GHG flux monitoring programs and reviewed values from literature. Land use types in GHG comparisons include selectively logged non-drained and drainage affected peat swamp forests, plantations, agricultural peat, and mismanaged abandoned peatlands. The results are discussed on basis of GHG dynamics controlling factors in various tropical peat land uses.

  20. Lead content and isotopic composition in submound and recent soils of the Volga Upland

    NASA Astrophysics Data System (ADS)

    Pampura, T. V.; Probst, A.; Ladonin, D. V.; Demkin, V. A.

    2013-11-01

    Literature data on the historical reconstructions of the atmospheric lead deposition in Europe and the isotopic composition of the ores that are potential sources of the anthropogenic lead in the atmospheric deposition in the lower Volga steppes during different time periods have been compiled. The effect of the increasing anthropogenic lead deposition recorded since the Bronze Age on the level of soil contamination has been investigated. For the first time paleosol buried under a burial mound of the Bronze Age has been used as a reference point to assess of the current contamination level. The contents and isotopic compositions of the mobile and total lead have been determined in submound paleosols of different ages and their recent remote and roadside analogues. An increase in the content and fraction of the mobile lead and a shift of its isotopic composition toward less radiogenic values (typical for lead from the recent anthropogenic sources) has been revealed when going from a Bronze-Age paleosol to a recent soil. In the Bronze-Age soil, the isotopic composition of the mobile lead is inherited from the parent rock to a greater extent than in the modern soils, where the lead is enriched with the less radiogenic component. The effect of the anthropogenic component is traced in the analysis of the mobile lead, but it is barely visible for the total lead. An exception is provided by the recent roadside soils characterized by increased contents and the significantly less radiogenic isotopic composition of the mobile and total lead.

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

    PubMed

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

    2015-04-01

    Most often, only total mercury concentrations in soil samples are determined in environmental studies. However, the determination of extremely toxic methylmercury (MeHg) in addition to the total mercury is critical to understand the biogeochemistry of mercury in the environment. In this study, N2-assisted distillation and acidic KBr/CuSO4 solvent extraction methods were applied to isolate MeHg from wet peat soil samples collected from boreal forest catchments. Determination of MeHg was performed using a purge and trap GC-ICP-MS technique with a species-specific isotope dilution quantification. Distillation is known to be more prone to artificial MeHg formation compared to solvent extraction which may result in the erroneous MeHg results, especially with samples containing high amounts of inorganic mercury. However, methylation of inorganic mercury during the distillation step had no effect on the reliability of the final MeHg results when natural peat soil samples were distilled. MeHg concentrations determined in peat soil samples after distillation were compared to those determined after the solvent extraction method. MeHg concentrations in peat soil samples varied from 0.8 to 18 ?g kg(-1) (dry weight) and the results obtained with the two different methods did not differ significantly (p=0.05). The distillation method with an isotope dilution GC-ICP-MS was shown to be a reliable method for the determination of low MeHg concentrations in unpolluted soil samples. Furthermore, the distillation method is solvent-free and less time-consuming and labor-intensive when compared to the solvent extraction method. PMID:25434268

  2. Contemporary Subsoil Carbon Accumulation During Reforestation is Conditioned by Long-term, Coupled C-Fe Cycling in Upland Soils

    NASA Astrophysics Data System (ADS)

    Bacon, A. R.; Richter, D., Jr.; Heckman, K. A.; Veverica, T. J.; Nave, L. E.

    2014-12-01

    To understand deep soil carbon stabilization and change during reforestation we sampled bulk subsoils and individual redoximorphic features from a network of two meter deep soil pits along a gentle catena (3% slope) in the Southern Piedmont of North Carolina, USA. Until 1910, the catena was under cultivation. Since then, half of the soils we excavated have supported deeply rooted pine forests while the other half have continued to support relatively shallow rooted grasses and forbs. Across the catena, accordant with the divergent rooting regimes, subsoil roots were three times more abundant under forest than grass, and ?14C in bulk subsoil samples was enriched by an average of 123‰ under forest relative to grass (p=0.0267). Bulk subsoils, however, were extremely heterogeneous and contained three well-defined redoximorphic feature microsites. Over the lifetime of these upland soils, coupled carbon-iron cycling during transient oxygen limitation created the microsites and thereby imparted subsoils with steep biogeochemical gradients millimeters to centimeters apart. Concentration of operationally defined crystalline iron-oxyhydroxides was on average ten times higher in Fe-enriched microsites (30.1 ± 2.5 mg/g, mean ± 1 SE) than Fe-depleted microsites (2.9 ± 0.3 mg/g) and gley microsites (3.3 ± 0.4 mg/g) across the catena. Under the deeply rooted forest ?14C in gley microsites and Fe-depleted microsites was enriched by an average of 73‰ (p=0.0194) and 94‰ (p=0.0416), respectively relative to the same microsites under grass. Meanwhile, ?14C in Fe-enriched microsites was unchanged by the divergent rooting regimes (p=0.1936). These microsite dependent patterns of radiocarbon enrichment indicate that subsoil C stabilization during reforestation of the catena was spatially conditioned by historic coupled carbon-iron cycling. We detail the mechanisms of this conditioning, and argue that similar long-term biogeochemical processes influence contemporary subsoil C stabilization and change more often than is commonly appreciated.

  3. PHOSPHORUS COMPOSITION OF UPLAND SOILS POLLUTED BY LONG-TERM ATMOSPHERIC NITROGEN DEPOSITION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Atmospheric N deposition can enhance biological P limitation in terrestrial ecosystems and increase the importance of organic P to plants and microorganisms. We used NaOH-EDTA extraction and phosphorus-31 NMR spectroscopy to determine the P composition of soils in the Upper Teesdale National Nature...

  4. Reorganization of vegetation, hydrology and soil carbon after permafrost degradation across heterogeneous boreal landscapes

    NASA Astrophysics Data System (ADS)

    Torre Jorgenson, M.; Harden, Jennifer; Kanevskiy, Mikhail; O'Donnell, Jonathan; Wickland, Kim; Ewing, Stephanie; Manies, Kristen; Zhuang, Qianlai; Shur, Yuri; Striegl, Robert; Koch, Josh

    2013-09-01

    The diversity of ecosystems across boreal landscapes, successional changes after disturbance and complicated permafrost histories, present enormous challenges for assessing how vegetation, water and soil carbon may respond to climate change in boreal regions. To address this complexity, we used a chronosequence approach to assess changes in vegetation composition, water storage and soil organic carbon (SOC) stocks along successional gradients within four landscapes: (1) rocky uplands on ice-poor hillside colluvium, (2) silty uplands on extremely ice-rich loess, (3) gravelly-sandy lowlands on ice-poor eolian sand and (4) peaty-silty lowlands on thick ice-rich peat deposits over reworked lowland loess. In rocky uplands, after fire permafrost thawed rapidly due to low ice contents, soils became well drained and SOC stocks decreased slightly. In silty uplands, after fire permafrost persisted, soils remained saturated and SOC decreased slightly. In gravelly-sandy lowlands where permafrost persisted in drier forest soils, loss of deeper permafrost around lakes has allowed recent widespread drainage of lakes that has exposed limnic material with high SOC to aerobic decomposition. In peaty-silty lowlands, 2-4 m of thaw settlement led to fragmented drainage patterns in isolated thermokarst bogs and flooding of soils, and surface soils accumulated new bog peat. We were not able to detect SOC changes in deeper soils, however, due to high variability. Complicated soil stratigraphy revealed that permafrost has repeatedly aggraded and degraded in all landscapes during the Holocene, although in silty uplands only the upper permafrost was affected. Overall, permafrost thaw has led to the reorganization of vegetation, water storage and flow paths, and patterns of SOC accumulation. However, changes have occurred over different timescales among landscapes: over decades in rocky uplands and gravelly-sandy lowlands in response to fire and lake drainage, over decades to centuries in peaty-silty lowlands with a legacy of complicated Holocene changes, and over centuries in silty uplands where ice-rich soil and ecological recovery protect permafrost.

  5. Reorganization of vegetation, hydrology and soil carbon after permafrost degradation across heterogeneous boreal landscapes

    USGS Publications Warehouse

    Jorgenson, M. Torre; Harden, Jennifer; Kanevskiy, Mikhail; O'Donnell, Jonathan; Wickland, Kim; Ewing, Stephanie; Manies, Kristen; Zhuang, Qianlai; Shur, Yuri; Striegl, Robert; Koch, Josh

    2013-01-01

    The diversity of ecosystems across boreal landscapes, successional changes after disturbance and complicated permafrost histories, present enormous challenges for assessing how vegetation, water and soil carbon may respond to climate change in boreal regions. To address this complexity, we used a chronosequence approach to assess changes in vegetation composition, water storage and soil organic carbon (SOC) stocks along successional gradients within four landscapes: (1) rocky uplands on ice-poor hillside colluvium, (2) silty uplands on extremely ice-rich loess, (3) gravelly–sandy lowlands on ice-poor eolian sand and (4) peaty–silty lowlands on thick ice-rich peat deposits over reworked lowland loess. In rocky uplands, after fire permafrost thawed rapidly due to low ice contents, soils became well drained and SOC stocks decreased slightly. In silty uplands, after fire permafrost persisted, soils remained saturated and SOC decreased slightly. In gravelly–sandy lowlands where permafrost persisted in drier forest soils, loss of deeper permafrost around lakes has allowed recent widespread drainage of lakes that has exposed limnic material with high SOC to aerobic decomposition. In peaty–silty lowlands, 2–4 m of thaw settlement led to fragmented drainage patterns in isolated thermokarst bogs and flooding of soils, and surface soils accumulated new bog peat. We were not able to detect SOC changes in deeper soils, however, due to high variability. Complicated soil stratigraphy revealed that permafrost has repeatedly aggraded and degraded in all landscapes during the Holocene, although in silty uplands only the upper permafrost was affected. Overall, permafrost thaw has led to the reorganization of vegetation, water storage and flow paths, and patterns of SOC accumulation. However, changes have occurred over different timescales among landscapes: over decades in rocky uplands and gravelly–sandy lowlands in response to fire and lake drainage, over decades to centuries in peaty–silty lowlands with a legacy of complicated Holocene changes, and over centuries in silty uplands where ice-rich soil and ecological recovery protect permafrost.

  6. Metal and arsenic impacts to soils, vegetation communities and wildlife habitat in southwest Montana uplands contaminated by smelter emissions. 1: Field evaluation

    SciTech Connect

    Galbraith, H.; LeJeune, K.; Lipton, J.

    1995-11-01

    Concentrations of arsenic and metals in soils surrounding a smelter in southwest Montana were correlated with vegetative community structure and composition and wildlife habitat quality. Soils in the uplands surrounding the smelter were highly enriched with arsenic and metals. Concentrations of these analytes decreased with distance from the smelter and with soil depth, suggesting that the smelter is the source of the enrichment. In enriched areas, marked modifications to the native vegetation community structure and composition were observed. These included replacement of evergreen forest with bare unvegetated ground; species impoverishment and increased dominance by weed species in grasslands; and reductions in the vertical complexity of the habitat. Significant negative correlations existed between soil arsenic and metals concentrations and the extent of vegetative cover and the vertical diversity of plant communities. Loss of vegetative cover in the affected areas has been accompanied by reductions in their capacity to support indigenous wildlife populations.

  7. 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.

  8. Rapid immobilisation and leaching of wet-deposited nitrate in upland organic soils.

    PubMed

    Evans, Chris D; Norris, Dave; Ostle, Nick; Grant, Helen; Rowe, Edwin C; Curtis, Chris J; Reynolds, Brian

    2008-12-01

    Nitrate (NO3-) is often observed in surface waters draining terrestrial ecosystems that remain strongly nitrogen (N) limited. It has been suggested that this occurs due to hydrological bypassing of soil or vegetation N retention, particularly during high flows. To test this hypothesis, artificial rain events were applied to 12 replicate soil blocks on a Welsh podzolic acid grassland hillslope, labelled with 15N-enriched NO3- and a conservative bromide (Br-) tracer. On average, 31% of tracer-labelled water was recovered within 4 h, mostly as mineral horizon lateral flow, indicating rapid vertical water transfer through the organic horizon via preferential flowpaths. However, on average only 6% of 15N-labelled NO3- was recovered. Around 80% of added NO3- was thus rapidly immobilised, probably by microbial communities present on the surfaces of preferential flowpaths. Transitory exceedance of microbial N-uptake capacity during periods of high water and N flux may therefore provide a mechanism for NO3- leaching. PMID:18653264

  9. The effects of ecological restoration, on soil-pore water quality and DOC concentrations, on a British upland blanket bog.

    NASA Astrophysics Data System (ADS)

    Qassim, Suzane; Dixon, Simon; Rowson, James; Worrall, Fred; Evans, Martin

    2013-04-01

    Polluted by past atmospheric deposition, eroded and burnt, the Bleaklow plateau (Peak district National Park, UK) has long been degraded. Peatlands are important carbon reservoirs and can act as sources or sinks of carbon. Dissolved organic carbon (DOC) is carbon lost from peatlands via the fluvial pathway and as the major component of water colour it is costly to remove during water treatment processes. The Bleaklow Summit peatlands, were subjected to a large wildfire in 2003 devegetating 5.5km2. This fire prompted stakeholders to initiate a large-scale programme of restoration of the plateau. This study considered restoration techniques across four sites: all four sites were seeded with lawn grass, limed and fertilised; to raise the pH and allow establishment of vegetation. In addition to these interventions, one site also had a mulch of Calluna vulgaris applied to the surface to allow soil stabilisation and promote vegetation establishment and another site had biodegradable geojute textile mesh installed, to stabilize the steep gully surfaces. Another site had a gully block installed, to reduce peat desiccation and erosion. This study will compare the four restored sites to two types of comparators: bare soil sites where no restoration was undertaken and a naturally vegetated site unaffected by the 2003 wildfire. Each site had six replicate dipwells, installed in two groups of three. The depth to the water table was monitored and soil water samples collected for analysis, monthly for 5 years, from Nov 2006 - Jan 2012. No significant difference in DOC concentration was found between control and treated sites. There was, however, a significant difference in DOC composition between sites and over the 5 year period of monitoring. UV-vis absorbance of the samples is used to quantify the fulvic to humic components of DOC. The vegetated control was not significantly different to the bare sites; however the vegetated control had a significantly greater humic fraction of than the seeded, limed and fertilised only site, as well as the seeded, limed, C. vulgaris mulched site. This is possibly related to vegetation and litter layer establishment. A suite of water quality data (conductivity, pH and cation data) are now being analysed in combination with DOC to increase understanding of the relationship between bare site re-vegetation and DOC compositional change.

  10. Impact of managed moorland burning on peat nutrient and base cation status

    NASA Astrophysics Data System (ADS)

    Palmer, Sheila; Gilpin, Martin; Wearing, Catherine; Johnston, Kerrylyn; Holden, Joseph; Brown, Lee

    2013-04-01

    Controlled 'patch' burning of moorland vegetation has been used for decades in the UK to stimulate growth of heather (Calluna vulgaris) for game bird habitat and livestock grazing. Typically small patches (300-900 m2) are burned in rotations of 8-25 years. However, our understanding of the short-to-medium term environmental impacts of the practice on these sensitive upland areas has so far been limited by a lack of scientific data. In particular the effect of burning on concentrations of base cations and acid-base status of these highly organic soils has implications both for ecosystem nutrient status and for buffering of acidic waters. As part of the EMBER project peat chemistry data were collected in ten upland blanket peat catchments in the UK. Five catchments were subject to a history of prescribed rotational patch burning. The other five catchments acted as controls which were not subject to burning, nor confounded by other detrimental activities such as drainage or forestry. Soil solution chemistry was also monitored at two intensively studied sites (one regularly burned and one control). Fifty-centimetre soil cores, sectioned into 5-cm intervals, were collected from triplicate patches of four burn ages at each burned site, and from twelve locations at similar hillslope positions at each control site. At the two intensively monitored sites, soil solution chemistry was monitored at four depths in each patch. Across all sites, burned plots had significantly smaller cation exchange capacities, lower concentrations of exchangeable base cations and increased concentrations of exchangeable H+ and Al3+ in near-surface soil. C/N ratios were also lower in burned compared to unburned surface soils. There was no consistent trend between burn age and peat chemistry across all burned sites, possibly reflecting local controls on post-burn recovery rates or external influences on burn management decisions. At the intensively monitored site, plots burned less than two years prior to sampling had significantly smaller exchange capacities and lower concentrations of soil base cations in surface soils relative to plots burned 15-25 years previously. In contrast, surface soil solutions in recently burned plots were enriched in base cations relative to older plots and relative to the control site, possibly due to enhanced leaching at bare soil surfaces. The results offer evidence for an impact of burning on peat nutrient and acid-base status, but suggest that soils recover given time with no further burning.

  11. Interactive effects of fire, soil climate, and vegetation on CO2 fluxes in an upland black spruce forest and peatland in interior Alaska

    NASA Astrophysics Data System (ADS)

    O'Donnell, J. A.; Turetsky, M. R.; Harden, J. W.; Manies, K. L.; Pruett, L. E.

    2007-12-01

    Fire is an important control on the carbon (C) balance of the boreal forest. In addition to the immediate release of stored C to the atmosphere through organic matter combustion, fire has the capacity to alter controls on decomposition, through changes in soil climate and substrate quality. Here, we present findings from two complimentary studies that examine how fire modifies the physical properties of soil and how these modifications influence rates of decomposition and C exchange in Alaska's boreal forest. First, we conducted a laboratory study to evaluate the interactive effects of fire, soil temperature, soil moisture, and moss type on CO2 fluxes from organic soils. Second, we conducted intensive field measurements of ecosystem CO2 fluxes in a 3 year-old burn to evaluate the effect of fire on carbon exchange in an upland forest and peatland in interior Alaska. Incubation CO2 fluxes showed a significant interaction between burn status (burned, unburned sites), temperature (2 °C vs. 20 °C treatments), and moisture treatment (field moisture vs. saturated). Incubation CO2 fluxes in the unburned sites increased with temperature by a factor of 5 and 29, whereas incubation CO2 fluxes in the burned sites only increased by 6 to 8 times. Incubation CO2 fluxes in the unburned sites increased with moisture content between 19 and 24 times, whereas incubation CO2 fluxes in the burned sites only increased by a factor of 4. Incubation CO2 fluxes from unburned Sphagnum samples were nearly 3 times greater than fluxes from burned Sphagnum. In the field At 3 years post-burn, moisture content was higher in the burned upland forest and burned peatland relative the unburned sites. However, soil temperature was not significantly different between burned and unburned sites. Mean rates of net ecosystem exchange (NEE) showed greater rates of CO2 uptake in the unburned peatland site than in the burned peatland, averaging -1.51 and 0.16 g C m-2 d-1, respectively. NEE rates were not significantly different in the two upland forest sites, averaging 0.0005 g C m-2 d-1 across sites. Mean rates of ecosystem respiration (ER) were not significantly different between the burned and unburned upland forest sites, averaging 0.9 g C m-2 d-1 overall. ER rates were not different between the burned and unburned peatland sites, averaging 1.4 m-2 d-1 overall. Soil temperature and moisture content accounted for between 20 to 45 % of the variation in ER rates in unburned upland forest and unburned peatland, and less than 10 % in the two burned sites. These findings, together with the incubation study, suggest that while fire creates soil climate conditions more conducive to rapid decomposition, rates of C release from soils may be constrained following fire by changes in litter quality that slow rates of decomposition.

  12. The Severity of Smouldering Peat Fires and Damage to the Forest Soil 

    E-print Network

    Rein, Guillermo; Cleaver, Natalie; Ashton, Clare; Pironi, Paolo; Torero, Jose L

    Smouldering wildfires propagate slowly through surface and subsurface organic layers of the forest ground and severely affect the soil, producing physical, chemical and biological changes. These effects are caused by the prolonged heating...

  13. Thermal properties of peat, marshy and mineral soils in relation to soil moisture status in Polesie and Biebrza wetlands

    NASA Astrophysics Data System (ADS)

    Usowicz, Boguslaw; ?ukowski, Mateusz; Marczewski, Wojciech; Usowicz, Jerzy B.; Lipiec, Jerzy; Stankiewicz, Krystyna

    2013-04-01

    Knowledge of thermal properties of soil helps in estimating heat fluxes as an important component of the heat balance. The research was conducted to evaluate spatial distribution of the soil thermal properties (thermal conductivity, heat capacity and thermal diffusivity) in relation to soil wetness and bulk density in wetland soils of Polesie and Biebrza regions (Poland). Soil moisture content and bulk density together with soil temperature and texture data, were used for determination of thermal properties. The thermal conductivity was measured, by KD2 Pro Decagon, and calculated by the physical-statistical model of Usowicz, and the heat capacity - was calculated with empirical formulae, and the thermal diffusivity was determined by the ratio of thermal conductivity to the heat capacity. The thermal conductivity of wetland and marsh soils increases with increasing moisture content and density of the soil to higher extent in soils richer in minerals - mostly quartz. Maximum thermal conductivity of the wetland soils at different density did not exceed the value of the thermal conductivity of water. However, for mineral soil at the natural density (1.31 Mg m-3) and with the quartz content of 96%, the thermal conductivity is about four times greater than the thermal conductivity of water. This is due to that the thermal conductivity of quartz is sixteen times greater than that of water. Dependence of the soil thermal conductivity on moisture content is non-linear and the shape of the non-linearity largely depends on the density of the soil. Particular components of soil bring their contribution to the conductivity respectively to their fractions and compounds being dominant in the ground contribute mostly to the effective slope of the thermal conductivity versus the water content at a given soil density. The heat capacity of the soil substrate is linearly dependent on the water content. Soils containing more organic matter within low specific densities, usually are characterized by less or minimal available heat capacity values in dry conditions, while they can also be characterized by highest or maximal heat capacity values, in highly wet conditions approaching the saturation with water. The increase in soil density caused a parallel shift of the characteristics of the heat capacity in the direction of higher values. This was associated with an increase in solids content per unit volume of the substrate and the reduction of the water content and the specific heat capacity of the individual components of the soil. Thermal diffusivity of soils exhibits characteristic extremes. In organic soils characteristic minimal or maximal extremes may occur, while mineral soils achieve only maximal diffusivity values on regular basis. Extremes of the thermal diffusivity are mainly due to the changes in the intensity of the thermal conductivity of the substrate due to change in soil moisture content and density. The heat capacity of the soil increases with increasing moisture content at the constant rate. The value of soil thermal diffusivity depends highly on quartz content. Thermal diffusivity of the soil with the same moisture content was greater for the higher densities, and minimum or maximum thermal diffusivity tends to move toward the lower moisture content for higher densities. The observed extremes are so distinctive that they determine the value of soil moisture and density, at which the temperature wave travels the slowest and the fastest in the soil. The question of determining and sensing the water capacity is also affected by the texture and porosity. Simple volumetric measures of porosity are used, but with distinguishing the volume of pores filled by air and other part filled with water. Practically, porosity is treated simply and is included to assessments by effects on the thermal properties. We prove that thermal properties are very good variables for a sensitive indicator of the water content, and accounting the impact from porosity. Thermal properties gather effects from the texture and porosity cumulatively. Therefo

  14. Copper tolerance of the biomass crops Elephant grass (Pennisetum purpureum Schumach), Vetiver grass (Vetiveria zizanioides) and the upland reed (Phragmites australis) in soil culture.

    PubMed

    Liu, Xinghua; Shen, Yixing; Lou, Laiqing; Ding, Chenglong; Cai, Qingsheng

    2009-01-01

    Pot trials were conducted to study the influence of copper (Cu) on the growth and biomass of Elephant grass (EG, Pennisetum purpureum Schumach), Vetiver grass (VG, Vetiveria zizanioides) and the upland reed (UR, Phragmites australis). Cu toxicity in EG, VG and UR was positively correlated with the total and bioavailable Cu concentrations in the soil. Based on the EC50, dry weights, Cu contents, chlorophyll contents and photosynthesis rates, the Cu tolerance of the three species followed the trend EGNVGNUR. There were no significant differences in the unit calorific values among the different plants, though the total calorific values of EG were higher than those of VG and UR due to its higher biomass. The addition of KH2PO4 to the soil decreased the bioavailability of Cu and the Cu uptake by plants. EG could therefore be a good candidate for growth on Cu-contaminated soils, especially those improved by phosphate. PMID:19393734

  15. Chemically enhanced mixed region vapor stripping of TCE-contaminated saturated peat and silty clay soils

    SciTech Connect

    West, O.R.; Cameron, P.A.; Lucero, A.J.; Koran, L.J. Jr.

    1996-01-01

    The objective of this study was to conduct further testing of MRVS, chemically enhanced with calcium oxide conditioning, on field- contaminated soils collected from beneath the NASA Michoud Rinsewater Impoundment. In this study, residual soil VOC levels as a function of vapor stripping time were measured to quantify VOC removal rates. Physical and chemical soil parameters expected to affect MRVS efficiency were measures. The effects of varying the calcium oxide loadings as well as varying the vapor stripping flow rates on VOC removal were also evaluated. The results of this study will be used to determine whether acceptable removals can be achieved within reasonable treatment times, remediation costs being directly proportional to the latter. The purpose of this report is to document the experimental results of this study, as well as to address issues that were raised after completion of the previous Michoud treatability work.

  16. Influence of geology, regolith and soil on fluid flow pathways in an upland catchment in central NSW, Australia

    NASA Astrophysics Data System (ADS)

    Bernardi, Tony

    2014-05-01

    Influence of geology, regolith and soil on fluid flow pathways in an upland catchment in central NSW, Australia. Tony Bernardi and Leah Moore Dryland Salinity Hazard Mitigation Program (DSHMP), University of Canberra, ACT 2601, AUSTRALIA The diversity of salt expression in central NSW has defied classification because salt expression, mobilisation and transport is highly variable and is typically site specific. Hydrological models are extensively used to simulate possible outcomes for a range of land use changes to mitigate the mobilisation and transport of salt into the streams or across the land surface. The ability of these models to mimic reality can be variable thereby reducing the confidence in the models outputs and uptake of strategic management changes by the community. This study focuses on a 250 ha semi-arid sub-catchment of Little River catchment in central west NSW in the Murray-Darling Basin, Australia. We propose that an understanding the structure of the landforms and configuration of rock, regolith and soil materials at the study site influences fluid flow pathways in the landscape and can be related to observed variations in the chemical composition and salinity of surface and aquifer water. Preliminary geological mapping of the site identified the dominant rock type as a pink and grey dacite and in localised mid-slope areas, a coarsely crystalline biotite-phyric granodiorite. Samples were taken at regular intervals from natural exposures in eroded stream banks and in excavations made during the installation of neutron moisture meter tubes. In order to establish mineral weathering pathways, samples were taken from the relatively unweathered core to the outer weathered 'onion skins' of corestones on both substrates, and then up through the regolith profile, including the soil zone, to the land surface. X-ray diffraction (XRD) analysis and X-ray fluorescence (XRF) was conducted on the rock and soil/saprock samples. Electromagnetic induction (EMI) profile data were compiled from previous work with colleagues in this area. Preliminary interpretation of the mapping and the geophysics is that there is a three-layer framework for groundwater modelling: fractured granitic rock with an irregular upper surface, finer-grained (volcanic) rock that has either mantled the older granite or has been intruded into, and a weathering profile developed in relation to the land surface. More careful interpretation of the intervals that shallow and deep piezometers and shallow and deep bores are sampling indicates that variability in water chemistry between holes can, in part, be explained because they are sampling different materials in the sub-surface geology/regolith geology. Quartz is a relatively resistant phase throughout the profiles. For both substrates there is a decrease in the feldspar in increasingly weathered regolith materials, with a corresponding increase in kaolinite clay. There is increased homogenisation of the profile, and some horizonation due to pedogenic processes (e.g. bioturbation, illuviation of fines down profile) nearer the land surface. This results in a concentration of more resistant phases (quartz and remnant primary feldspar as sands) at the land surface over the granitic substrate, however kaolinite persists in the profile over the finer substrate. The presence of measurable ferruginous oxides and sesquioxides relates to localised percolation of oxidising fluids through the profiles. Understanding the configuration and composition of rocks and regolith materials in the Baldry catchment facilitates interpretation of observed patterns in hydrological analyses.

  17. Global Perspectives on Peat Fires

    NASA Astrophysics Data System (ADS)

    Watts, A.; Turetsky, M. R.; Benscoter, B.; Page, S. E.; Rein, G.; van der Werf, G.

    2014-12-01

    The global peat carbon pool exceeds that of global vegetation and is similar to the current atmospheric carbon pool. Because fire is increasingly appreciated as a threat to peatlands and their carbon stocks, here we discuss controls on and effects of peat fires across biomes and how they vary. Peat fires are dominated by smoldering combustion, which is easier to ignite and persists under greater moisture content than flaming combustion. In undisturbed peatlands, the peat C stock typically is protected from deep smoldering, and fire resistance has played a role in tropical and boreal peat carbon storage over millennia. However, drying mediated by climate change and anthropogenic activity is altering peatland hydrology and increasing the frequency and extent of peat fires; in some cases, processes of drying and fire may be coupled in positive feedbacks that could result in increasingly large fires and consequent releases of carbon to the atmosphere. The combustion of deep peat affects older soil carbon that has not been part of the active carbon cycle for centuries to millennia, and will dictate the importance of peat fire emissions with respect to future climate change and human health effects.

  18. Transport of lead and diesel fuel through a peat soil near Juneau, AK: a pilot study

    E-print Network

    . This project is important to southeast Alaskan communities because limited land resources are forcing to a nearby rifle range using DRO-contaminated soil posed a potential risk to an anadromous fish) was passed through each column and leachate was collected at regular intervals. The results showed

  19. TRIHALOMETHANE REACTIVITY OF WATER- AND SODIUM HYDROXIDE-EXTRACTABLE ORGANIC CARBON FRACTIONS FROM PEAT SOILS.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Certain organic carbon moieties in drinking source waters of the Sacramento–San Joaquin Delta can react with chlorine during disinfection to form potentially carcinogenic and mutagenic trihalomethanes. The properties of reactive organic carbon in Delta waters, particularly those of soil origin, have...

  20. Soil data from fire and permafrost-thaw chronosequences in upland Picea mariana stands near Hess Creek and Tok, interior Alaska

    USGS Publications Warehouse

    O'Donnell, Jonathan A.; Harden, Jennifer W.; Manies, Kristen L.; Jorgenson, M. Torre; Kanevskiy, Mikhail; Xu, Xiaomei

    2013-01-01

    Soils of the Northern Circumpolar Permafrost region harbor 1,672 petagrams (Pg) (1 Pg = 1,000,000,000 kilograms) of organic carbon (OC), nearly 50 percent of the global belowground OC pool (Tarnocai and others, 2009). Of that soil OC, nearly 88 percent is presently stored in perennially frozen ground. Recent climate warming at northern latitudes has resulted in warming and thawing of permafrost in many regions (Osterkamp, 2007), which might mobilize OC stocks from associated soil reservoirs via decomposition, leaching, or erosion. Warming also has increased the magnitude and severity of wildfires in the boreal region (Turetsky and others, 2011), which might exacerbate rates of permafrost degradation relative to warming alone. Given the size and vulnerability of the soil OC pool in permafrost soils, permafrost thaw will likely function as a strong positive feedback to the climate system (Koven and others, 2011; Schaefer and others, 2011). In this report, we report soil OC inventories from two upland fire chronosequences located near Hess Creek and Tok in Interior Alaska. We sampled organic and mineral soils in the top 2 meters (m) across a range of stand ages to evaluate the effects of wildfire and permafrost thaw on soil C dynamics. These data were used to parameterize a simple process-based fire-permafrost-carbon model, which is described in detail by O’Donnell and others (2011a, b). Model simulations examine long-term changes in soil OC storage in response to fire, permafrost thaw, and climate change. These data also have been used in other papers, including Harden and others (2012), which examines C recovery post-fire, and Johnson and others (2011), which synthesizes data within the Alaska Soil Carbon Database. Findings from these studies highlight the importance of climate and disturbance (wildfire, permafrost thaw) on soil C storage, and loss of soil C from high-latitude ecosystems.

  1. Evidence for an eolian origin for the silt-enriched soil mantles on the glaciated uplands of eastern Upper Michigan, USA

    USGS Publications Warehouse

    Schaetzl, R.J.; Loope, W.L.

    2008-01-01

    We provide textural, geochemical, and mineralogical data on a thin, silty deposit that unconformably mantles glaciated uplands in the eastern Upper Peninsula of Michigan. Previous research on this deposit, which we hypothesize to be loess, is nonexistent. The uplands were islands or narrow peninsulas within one or more glacial lakes. We compare the distribution, likely source and nature of the 20-60??cm thick silty mantle by using the loess formation model of Mason et al. [Mason, J.A., Nater, E.A., Zanner, C.W., Bell, J.C., 1999. A new model of topographic effects on the distribution of loess. Geomorphology 28, 223-236], which focuses on the generation of eolian silt by saltating sand across upwind, barren surfaces. Parabolic dunes, with arms open to the NW, are common on former lake floors upwind of the silt-mantled uplands, attesting to the strength and direction of paleowinds. The abrupt termination of the dunes at the footslopes of the uplands, associated with silt deposition on upland soil surfaces in downwind locations, are both consistent with the model of Mason et al. [Mason, J.A., Nater, E.A., Zanner, C.W., Bell, J.C., 1999. A new model of topographic effects on the distribution of loess. Geomorphology 28, 223-236]. Sediments on former lake floors contain abundant strata of fine/medium sand and silt, and thus are likely sources for the silt and dune sand. The cap, dune and lake sediments are similar along many different geochemical axes, whereas the substrate sediment, i.e., the drift below the cap, is unique. Cap sediments, normally containing roughly 30% silt, are enriched in quartz and depleted in Ti and Zr, relative to dune sediment. The dune sediment, a more residual eolian deposit, is enriched in Ti and Zr, relative to the cap, probably due to its greater abundance of heavy minerals. Therefore, we conclude that the silty cap is loess that was deflated from abandoned lake floors after nearby glacial lakes drained, probably contemporaneously with dune migration across the former lake floors. ?? 2008 Elsevier B.V. All rights reserved.

  2. Metal and arsenic impacts to soils, vegetation communities and wildlife habitat in southwest Montana uplands contaminated by smelter emissions. 2: Laboratory phytotoxicity studies

    SciTech Connect

    Kapustka, L.A.; Lipton, J.; Galbraith, H.; Cacela, D.; LeJeune, K.

    1995-11-01

    Vegetation communities on metal- and arsenic-contaminated uplands surrounding a smelter in southwest Montana have been eliminated or highly modified. Laboratory toxicity tests were performed using site soils from the impacted areas to determine whether the soils limit the ability of plants to establish and grow. The germination and growth of alfalfa, lettuce, and wheat in impacted area soils was compared to germination and growth of the three species in reference soils. The degree of phytotoxicity was quantified using a species-endpoint toxicity score calculated on the magnitude of difference between germination and growth of plants in impacted and reference soils. The impacted soils exhibited substantial toxicity to plants: 5% of the sites were severely phytotoxic, 55% were highly phytotoxic, 10% were moderately phytotoxic, 20% were mildly phytotoxic, and 10% were nontoxic. Root growth was consistently the most affected endpoint (18 of 20 impacted soils) and reduction in root length and mass was observed. Correlation and partial correlation analysis was used to evaluate the causes of phytotoxicity. Concentrations of As, Cu, and Zn and, to a lesser extent, Pb and Cd were found to be positively correlated with phytotoxicity.

  3. Soil microbial respiration from various microhabitats in Arctic landscape: impact of soil type, environmental conditions and soil age

    NASA Astrophysics Data System (ADS)

    Biasi, Christina; Jokinen, Simo; Marushchak, Maija; Trubnikova, Tatiana; Hämäläinen, Kai; Oinonen, Markku; Martikainen, Pertti

    2014-05-01

    Soil respiration is the second largest C flux between atmosphere and terrestrial ecosystems after gross primary production. Carbon dioxide released from soils is thus a major contributor to the atmospheric CO2 concentration. Despite the global importance, soil respiration and its components (heterotrophic and autotrophic respiration) remain poorly understood and not well constrained fluxes of the terrestrial C cycle. This is particularly true for the Arctic, where huge amounts of the Earth's soil carbon is stored. Here, we report on heterotrophic soil respiration rates from various Arctic tundra microhabitats measured in situ. The study site was Seida (67°07'N, 62°57'E, 100 m a.s.l.) which is characterized by typical sub-arctic permafrost landscape which comprises raised, vegetated permafrost peat plateaus, interspersed with spots of bare peat surfaces (peat circles), and upland mineral soils. We used isotope partitioning approach based on differences in natural abundance of 14C between soil and plants to separate sources of soil-respired CO2. In addition, the tradition trenching approach was employed. Complementary laboratory incubations with homogenized soil were conducted to assess primary decomposability of the soils and to identify age of the CO2 released and thus get more information on the nature of the sources of respiration. The major aim was to link SMR rates with of soil type, land cover class, soil physic-chemical properties (e.g. water content), soil C stocks and age of soil. Results show that, despite profound differences in soil characteristics and primary decomposability of organic matter, surface CO2 fluxes derived from soil microbial respiration rates were rather similar between microhabitats. The only factor which influenced, at least to some extent, the respiration rates was total soil C (and N) stocks in surface soils. There was some evidence for reduced soil-related CO2 emissions from peatlands, though results were not consistent between the methods applied. It seems that the lower decomposability of peat is largely outweighed by higher C stocks at field conditions. Surprisingly, the bare surfaces (peat circles) with 3500 years old C at the surface exhibited about the largest soil microbial respiration rates among all sites as shown by both methods. This is likely due to the immature status of the peat which was during the bulk of its developmental time protected by permafrost, together with high C-densities. The observation is particularly relevant for decomposition of deeper peat at the permafrost-active layer interface in the large vegetated peat plateaus, where soil material similar to the bare surfaces can be found. The results suggest that the chemical nature and high age of the soil SOC in deep peat does not solely guarantee for resistance to decay. Thus, the study highlights risks for potential re-mobilization of C in deep peat soils following thawing. Soil microbial respiration rates need to be better known when predicting the overall carbon sink/source character of tundra ecosystems in a warming climate. Biasi C., Jokinen S., Marushchak M., Hämäläinen K., Trubnikova T., Oinonen M., Martikainen P. (2013). Microbial respiration in Arctic upland and peat soils as source of CO2. Ecosystems. DOI: 10.1007/s10021-013-9710-z.

  4. Metagenomic Insights into Anaerobic Metabolism along an Arctic Peat Soil Profile

    PubMed Central

    Lipson, David A.; Haggerty, John Matthew; Srinivas, Archana; Raab, Theodore K.; Sathe, Shashank; Dinsdale, Elizabeth A.

    2013-01-01

    A metagenomic analysis was performed on a soil profile from a wet tundra site in northern Alaska. The goal was to link existing biogeochemical knowledge of the system with the organisms and genes responsible for the relevant metabolic pathways. We specifically investigated how the importance of iron (Fe) oxides and humic substances (HS) as terminal electron acceptors in this ecosystem is expressed genetically, and how respiratory and fermentative processes varied with soil depth into the active layer and into the upper permafrost. Overall, the metagenomes reflected a microbial community enriched in a diverse range of anaerobic pathways, with a preponderance of known Fe reducing species at all depths in the profile. The abundance of sequences associated with anaerobic metabolic processes generally increased with depth, while aerobic cytochrome c oxidases decreased. Methanogenesis genes and methanogen genomes followed the pattern of CH4 fluxes : they increased steeply with depth into the active layer, but declined somewhat over the transition zone between the lower active layer and the upper permafrost. The latter was relatively enriched in fermentative and anaerobic respiratory pathways. A survey of decaheme cytochromes (MtrA, MtrC and their homologs) revealed that this is a promising approach to identifying potential reducers of Fe(III) or HS, and indicated a possible role for Acidobacteria as Fe reducers in these soils. Methanogens appear to coexist in the same layers, though in lower abundance, with Fe reducing bacteria and other potential competitors, including acetogens. These observations provide a rich set of hypotheses for further targeted study. PMID:23741360

  5. Effects of the Application of Digestates from Wet and Dry Anaerobic Fermentation to Japanese Paddy and Upland Soils on Short-Term Nitrification

    PubMed Central

    Sawada, Kozue; Toyota, Koki

    2015-01-01

    Wet and dry anaerobic fermentation processes are operated for biogas production from organic matter, resulting in wet and dry digestates as by-products, respectively. The application of these digestates to soil as fertilizer has increased in recent years. Therefore, we herein compared the effects of applying wet digestates (pH 8.2, C/N ratio 4.5), dry digestates (pH 8.8, C/N ratio 23.4), and a chemical fertilizer to Japanese paddy and upland soils on short-term nitrification under laboratory aerobic conditions. Chloroform-labile C, an indicator of microbial biomass, was only minimally affected by these applications, indicating that a small amount of labile N was immobilized by microbes. All applications led to rapid increases in NO3 -N contents in both soils, and ammonia-oxidizing bacteria, but not archaea may play a critical role in net nitrification in the amended soils. The net nitrification rates for both soils were the highest after the application of dry digestates, followed by wet digestates and then the chemical fertilizer in order of decreasing soil pH. These results suggest that the immediate effects of applying digestates, especially dry digestates with the highest pH, on nitrate leaching need to be considered when digestates are used as alternative fertilizers. PMID:25740173

  6. Effects of the application of digestates from wet and dry anaerobic fermentation to Japanese paddy and upland soils on short-term nitrification.

    PubMed

    Sawada, Kozue; Toyota, Koki

    2015-01-01

    Wet and dry anaerobic fermentation processes are operated for biogas production from organic matter, resulting in wet and dry digestates as by-products, respectively. The application of these digestates to soil as fertilizer has increased in recent years. Therefore, we herein compared the effects of applying wet digestates (pH 8.2, C/N ratio 4.5), dry digestates (pH 8.8, C/N ratio 23.4), and a chemical fertilizer to Japanese paddy and upland soils on short-term nitrification under laboratory aerobic conditions. Chloroform-labile C, an indicator of microbial biomass, was only minimally affected by these applications, indicating that a small amount of labile N was immobilized by microbes. All applications led to rapid increases in NO3 -N contents in both soils, and ammonia-oxidizing bacteria, but not archaea may play a critical role in net nitrification in the amended soils. The net nitrification rates for both soils were the highest after the application of dry digestates, followed by wet digestates and then the chemical fertilizer in order of decreasing soil pH. These results suggest that the immediate effects of applying digestates, especially dry digestates with the highest pH, on nitrate leaching need to be considered when digestates are used as alternative fertilizers. PMID:25740173

  7. 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 statistically significant (Mann-Whitney U) difference in THM formation (p<0.05) as well as the amount of DOM produced and specific UV absorption at 254nm (p<0.01) between vegetation classes.

  8. Effect of reed canary grass cultivation on greenhouse gas emission from peat soil at controlled rewetting

    NASA Astrophysics Data System (ADS)

    Karki, S.; Elsgaard, L.; Lærke, P. E.

    2014-09-01

    Cultivation of bioenergy crops in rewetted peatland (paludiculture) is considered as a possible land use option to mitigate greenhouse gas (GHG) emissions. However, bioenergy crops like reed canary grass (RCG) can have a complex influence on GHG fluxes. Here we determined the effect of RCG cultivation on GHG emission from peatland rewetted to various extents. Mesocosms were manipulated to three different ground water levels (GWL), i.e., 0, -10 and -20 cm below the soil surface in a controlled semi-field facility. Emissions of CO2 (ecosystem respiration, ER), CH4 and N2O from mesocosms with RCG and bare soil were measured at weekly to fortnightly intervals with static chamber techniques for a period of one year. Cultivation of RCG increased both ER and CH4 emissions, but decreased the N2O emissions. The presence of RCG gave rise to 69, 75 and 85% of total ER at -20, -10 and 0 cm GWL, respectively However, this difference was due to decreased soil respiration at the rising GWL as the plant-derived CO2 flux was similar at all three GWL. For methane, 70-95% of the total emission was due to presence of RCG, with the highest contribution at -20 cm GWL. In contrast, cultivation of RCG decreased N2O emission by 33-86% with the major reductions at -10 and -20 cm GWL. In terms of global warming potential, the increase in CH4 emissions due to RCG cultivation was more than off-set by the decrease in N2O emissions at -10 and -20 cm GWL; at 0 cm GWL the CH4 emissions was offset only by 23%. CO2 emissions from ER obviously were the dominant RCG-derived GHG flux, but above-ground biomass yields, and preliminary measurements of gross photosynthetic production, show that ER could be more than balanced due to the uptake of CO2 by RCG. Our results support that RCG cultivation could be a good land use option in terms of mitigating GHG emission from rewetted peatlands, potentially turning these ecosystems into a sink of atmospheric CO2.

  9. Effect of reed canary grass cultivation on greenhouse gas emission from peat soil at controlled rewetting

    NASA Astrophysics Data System (ADS)

    Karki, S.; Elsgaard, L.; Lærke, P. E.

    2015-01-01

    Cultivation of bioenergy crops in rewetted peatland (paludiculture) is considered as a possible land use option to mitigate greenhouse gas (GHG) emissions. However, bioenergy crops like reed canary grass (RCG) can have a complex influence on GHG fluxes. Here we determined the effect of RCG cultivation on GHG emission from peatland rewetted to various extents. Mesocosms were manipulated to three different ground water levels (GWLs), i.e. 0, -10 and -20 cm below the soil surface in a controlled semi-field facility. Emissions of CO2 (ecosystem respiration, ER), CH4 and N2O from mesocosms with RCG and bare soil were measured at weekly to fortnightly intervals with static chamber techniques for a period of 1 year. Cultivation of RCG increased both ER and CH4 emissions, but decreased the N2O emissions. The presence of RCG gave rise to 69, 75 and 85% of total ER at -20, -10 and 0 cm GWL, respectively. However, this difference was due to decreased soil respiration at the rising GWL as the plant-derived CO2 flux was similar at all three GWLs. For methane, 70-95% of the total emission was due to presence of RCG, with the highest contribution at -20 cm GWL. In contrast, cultivation of RCG decreased N2O emission by 33-86% with the major reductions at -10 and -20 cm GWL. In terms of global warming potential, the increase in CH4 emissions due to RCG cultivation was more than offset by the decrease in N2O emissions at -10 and -20 cm GWL; at 0 cm GWL the CH4 emissions was offset only by 23%. CO2 emissions from ER were obviously the dominant RCG-derived GHG flux, but above-ground biomass yields, and preliminary measurements of gross photosynthetic production, showed that ER could be more than balanced due to the photosynthetic uptake of CO2 by RCG. Our results support that RCG cultivation could be a good land use option in terms of mitigating GHG emission from rewetted peatlands, potentially turning these ecosystems into a sink of atmospheric CO2.

  10. 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 although species-specific differences in Collembola feeding behavior appear to exist, species are very plastic in their diet. This implies that changes in C turnover rates with vegetation shifts, might well be due to diet shifts of the present decomposer community rather than by changes in species composition.

  11. Utilization of subsurface microbial electrochemical systems to elucidate the mechanisms of competition between methanogenesis and microbial iron(III)/humic acid reduction in Arctic peat soils

    NASA Astrophysics Data System (ADS)

    Friedman, E. S.; Miller, K.; Lipson, D.; Angenent, L. T.

    2012-12-01

    High-latitude peat soils are a major carbon reservoir, and there is growing concern that previously dormant carbon from this reservoir could be released to the atmosphere as a result of continued climate change. Microbial processes, such as methanogenesis and carbon dioxide production via iron(III) or humic acid reduction, are at the heart of the carbon cycle in Arctic peat soils [1]. A deeper understanding of the factors governing microbial dominance in these soils is crucial for predicting the effects of continued climate change. In previous years, we have demonstrated the viability of a potentiostatically-controlled subsurface microbial electrochemical system-based biosensor that measures microbial respiration via exocellular electron transfer [2]. This system utilizes a graphite working electrode poised at 0.1 V NHE to mimic ferric iron and humic acid compounds. Microbes that would normally utilize these compounds as electron acceptors donate electrons to the electrode instead. The resulting current is a measure of microbial respiration with the electrode and is recorded with respect to time. Here, we examine the mechanistic relationship between methanogenesis and iron(III)- or humic acid-reduction by using these same microbial-three electrode systems to provide an inexhaustible source of alternate electron acceptor to microbes in these soils. Chamber-based carbon dioxide and methane fluxes were measured from soil collars with and without microbial three-electrode systems over a period of four weeks. In addition, in some collars we simulated increased fermentation by applying acetate treatments to understand possible effects of continued climate change on microbial processes in these carbon-rich soils. The results from this work aim to increase our fundamental understanding of competition between electron acceptors, and will provide valuable data for climate modeling scenarios. 1. Lipson, D.A., et al., Reduction of iron (III) and humic substances plays a major role in anaerobic respiration in an Arctic peat soil. Journal of Geophysical Research-Biogeosciences, 2010. 115. 2. Friedman, E.S., et al., A cost-effective and field-ready potentiostat that poises subsurface electrodes to monitor bacterial respiration. Biosensors and Bioelectronics, 2012. 32(1): p. 309-313.

  12. Use of Computed Tomography Imaging for Qualifying Coarse Roots, Rhizomes, Peat, and Particle Densities in Marsh Soils

    EPA Science Inventory

    Computed tomography (CT) imaging has been used to describe and quantify subtidal, benthic animals such as polychaetes, amphipods, and shrimp. Here, for the first time, CT imaging is used to successfully quantify wet mass of coarse roots, rhizomes, and peat in cores collected from...

  13. XAFS studies of cobalt(II) binding by solid peat and soil-derived humic acids and plant-derived humic acid-like substances.

    PubMed

    Ghabbour, Elham A; Scheinost, Andreas C; Davies, Geoffrey

    2007-02-01

    This work has examined cobalt(II) binding by a variety of solid humic acids (HAs) isolated from peat, plant and soil sources at temperatures down to 60K. The results confirm that X-ray absorption near-edge spectroscopy (XANES) measurements cannot distinguish between aquo and carboxylato ligands in the inner coordination sphere of Co(II). However, between 1 and 2 inner-sphere carboxylato ligands can be detected in all the peat, plant and soil-derived HA samples by extended X-ray absorption fine structure (EXAFS) measurements, indicating inner-sphere coordination of HA-bound Co(II). The precision of C(carboxylate) detection is limited by the extent and quality of the data and the contribution from inner-sphere O to the Fourier transformed peaks used to detect carbon. Putative chelate ring formation is consistent with a relatively negative entropy change in step A, the stronger Co(II) binding step by HA functional groups, and could relate to 'non-exchangeable' metal binding by HSs. PMID:17140631

  14. Instrumenting an upland research catchment in Canterbury, New Zealand to study controls on variability of soil moisture, shallow groundwater and streamflow

    NASA Astrophysics Data System (ADS)

    McMillan, Hilary; Srinivasan, Ms

    2015-04-01

    Hydrologists recognise the importance of vertical drainage and deep flow paths in runoff generation, even in headwater catchments. Both soil and groundwater stores are highly variable over multiple scales, and the distribution of water has a strong control on flow rates and timing. In this study, we instrumented an upland headwater catchment in New Zealand to measure the temporal and spatial variation in unsaturated and saturated-zone responses. In NZ, upland catchments are the source of much of the water used in lowland agriculture, but the hydrology of such catchments and their role in water partitioning, storage and transport is poorly understood. The study area is the Langs Gully catchment in the North Branch of the Waipara River, Canterbury: this catchment was chosen to be representative of the foothills environment, with lightly managed dryland pasture and native Matagouri shrub vegetation cover. Over a period of 16 months we measured continuous soil moisture at 32 locations and near-surface water table (< 2 m) at 14 locations, as well as measuring flow at 3 stream gauges. The distributed measurement sites were located to allow comparisons between North and South facing locations, near-stream versus hillslope locations, and convergent versus divergent hillslopes. We found that temporal variability is strongly controlled by the climatic seasonal cycle, for both soil moisture and water table, and for both the mean and extremes of their distributions. Groundwater is a larger water storage component than soil moisture, and the difference increases with catchment wetness. The spatial standard deviation of both soil moisture and groundwater is larger in winter than in summer. It peaks during rainfall events due to partial saturation of the catchment, and also rises in spring as different locations dry out at different rates. The most important controls on spatial variability are aspect and distance from stream. South-facing and near-stream locations have higher water tables and more, larger soil moisture wetting events. Typical hydrological models do not explicitly account for aspect, but our results suggest that it is an important factor in hillslope runoff generation. Co-measurement of soil moisture and water table level allowed us to identify interrelationships between the two. Locations where water tables peaked closest to the surface had consistently wetter soils and higher water tables. These wetter sites were the same across seasons. However, temporary patterns of strong soil moisture response to summer storms did not correspond to the wetter sites. Total catchment spatial variability is composed of multiple variability sources, and the dominant type is sensitive to those stores that are close to a threshold such as field capacity or saturation. Therefore, we classified spatial variability as 'summer mode' or 'winter mode'. In summer mode, variability is controlled by shallow processes e.g. interactions of water with soils and vegetation. In winter mode, variability is controlled by deeper processes e.g. groundwater movement and bypass flow. Double flow peaks observed during some events show the direct impact of groundwater variability on runoff generation. Our results suggest that emergent catchment behaviour depends on the combination of these multiple, time varying components of variability.

  15. Sequence composition of BAC clones and SSR markers mapped to Upland cotton chromosomes 11 and 21 targeting resistance to soil-borne pathogens

    PubMed Central

    Wang, Congli; Ulloa, Mauricio; Shi, Xinyi; Yuan, Xiaohui; Saski, Christopher; Yu, John Z.; Roberts, Philip A.

    2015-01-01

    Genetic and physical framework mapping in cotton (Gossypium spp.) were used to discover putative gene sequences involved in resistance to common soil-borne pathogens. Chromosome (Chr) 11 and its homoeologous Chr 21 of Upland cotton (G. hirsutum) are foci for discovery of resistance (R) or pathogen-induced R (PR) genes underlying QTLs involved in response to root-knot nematode (Meloidogyne incognita), reniform nematode (Rotylenchulus reniformis), Fusarium wilt (Fusarium oxysporum f.sp. vasinfectum), Verticillium wilt (Verticillium dahliae), and black root rot (Thielaviopsis basicola). Simple sequence repeat (SSR) markers and bacterial artificial chromosome (BAC) clones from a BAC library developed from the Upland cotton Acala Maxxa were mapped on Chr 11 and Chr 21. DNA sequence through Gene Ontology (GO) of 99 of 256 Chr 11 and 109 of 239 Chr 21 previously mapped SSRs revealed response elements to internal and external stimulus, stress, signaling process, and cell death. The reconciliation between genetic and physical mapping of gene annotations from new DNA sequences of 20 BAC clones revealed 467 (Chr 11) and 285 (Chr 21) G. hirsutum putative coding sequences, plus 146 (Chr 11) and 98 (Chr 21) predicted genes. GO functional profiling of Unigenes uncovered genes involved in different metabolic functions and stress response elements (SRE). Our results revealed that Chrs 11 and 21 harbor resistance gene rich genomic regions. Sequence comparisons with the ancestral diploid D5 (G. raimondii), A2 (G. arboreum) and domesticated tetraploid TM-1 AD1 (G. hirsutum) genomes revealed abundance of transposable elements and confirmed the richness of resistance gene motifs in these chromosomes. The sequence information of SSR markers and BAC clones and the genetic mapping of BAC clones provide enhanced genetic and physical frameworks of resistance gene-rich regions of the cotton genome, thereby aiding discovery of R and PR genes and breeding for resistance to cotton diseases. PMID:26483808

  16. [Influence of paddy rice-upland crop rotation of cold-waterlogged paddy field on crops produc- tion and soil characteristics].

    PubMed

    Wang, Fei; Li, Qing-hua; Lin, Cheng; He, Chun-mei; Zhong, Shao-jie; Li, Yu; Lin, Xin-jian; Huang, Jian-cheng

    2015-05-01

    Two consecutive years (4-crop) experiments were conducted to study the influence of different paddy rice-upland crop rotation in cold-waterlogged paddy field on the growth of crops and soil characteristics. The result showed that compared with the rice-winter fallow (CK) pattern, the two-year average yield of paddy rice under four rotation modes, including rape-rice (R-R), spring corn-rice (C-R), Chinese milk vetch-rice (M-R) and bean-rice (B-R), were increased by 5.3%-26.7%, with significant difference observed in C-R and R-R patterns. Except for M-R pattern, the annual average total economic benefits were improved by 79.0%-392.4% in all rotation pattern compared with the CK, and the ration of output/input was enhanced by 0.06-0.72 unit, with the most significant effect found in the C-R pattern. Likewise, compared with the CK, the contents of chlorophyll and carotenoid, and net photosynthetic rate (Pn) of rice plant were all increased during the full-tillering stage of rice in all rotation patterns. The rusty lines and rusty spots of soils were more obvious compared with the CK during the rice harvest, particularly in R-R, C-R and B-R patterns. The ratio of water-stable soil macro aggregates of plough layer of soil (> 2 mm) decreased at different levels in all rotation patterns while the ratios of middle aggregate (0.25-2 mm, expect for M-R) and micro aggregate of soil (< 0.25 mm) were opposite. There was a decreasing trend for soil active reducing agents in all rotation patterns, whereas the available nutrient increased. The amounts of soil bacteria in C-R and B-R patterns, fungi in B-R rotation pattern, cellulose bacteria in R-R, C-R and B-R patterns and N-fixing bacteria in B-R pattern were improved by 285.7%-403.0%, 221.7%, 64.6-92.2% and 162.2%, respectively. Moreover, the differences in all microorganisms were significant. Thus, based on the experimental results of cold-waterlogged paddy field, it was concluded that changing from single cropping rice system to C-R, R-R and B-R rotation patterns had good effect in terms of improving total yield and economic benefits, and soil physical and chemical properties were improved. PMID:26571667

  17. Diagnostics of hydromorphism in soils of autonomous positions on the Severo-Sos'vinsk Upland (Western Siberia)

    NASA Astrophysics Data System (ADS)

    Avetov, N. A.; Sopova, E. O.; Golovleva, Yu. A.; Kiryushin, A. V.; Krasilnikov, P. V.

    2014-11-01

    The complex studies of hydromorphism features in taiga weakly differentiated soils using morphological (color), chemical (iron content in different extracts, indicators of reducing conditions (IRIS)), and geobotanic (using the Ramenskii scale) methods have led to ambiguous conclusions. In all the soils, surface gleying was manifested. According to the results obtained by different methods, the maximum reduction processes were related to either the sublitter or the next deeper horizon. The Schwertmann coefficient, the criterion of Bodegom, and the Ramenskii scale indicated an increase of hydromorphism in the soils studied in the following sequence: the lower part of the ridge slopes drained by the small gullies < the middle part of the slopes < the flat tops of the ridges < the depression between the ridges. The morphological diagnostics of gleying proved to be a less sensitive method, which can recognize only the most contrasting hydromorphic soils. The lower horizons in some taiga soils have a bluish gray color probably not related to the recent soil hydromorphism.

  18. 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.

  19. Lower variability of radionuclide activities in upland dairy products compared to soils and vegetation: implication for environmental survey.

    PubMed

    Pourcelot, L; Steinmann, P; Froidevaux, P

    2007-01-01

    Contamination of the environment by radionuclides is usually estimated using soil and grass sampling. However, radionuclides are often not homogeneously distributed in soils. In the alpine Mercantour region (Western Alps, France) a large heterogeneity in Chernobyl 137Cs deposition has been previously observed. Here we report additional 137Cs results together with new 90Sr and Pu data for soil, grass, milk, and cheese samples. The results show that radioisotopes from nuclear weapons tests fallout are more homogeneously distributed than Chernobyl 137Cs. Further, we observe that the 137Cs and 90Sr contents are less variable in milk samples than in grass or soil samples. This can be attributed to the homogenization effect of cow vagrancy during grazing. Hence milk seems to be a more robust sample than soil or grass to evaluate the extent of contamination on a regional scale. We explore this idea by comparing own unpublished 90Sr results and 90Sr results from the literature to establish the relationship between altitude of grazing and contamination of soil and milk for Western Europe. There is a significant positive correlation between soil contamination and altitude and an even closer correlation between milk 90Sr activity (A) and altitude (h): A = A0 + e(k x h) where A0 is the expected activity of milk sampled at sea level (A0 = 0.064 +/- 0.014 Bq g(-1) Ca) and h is the altitude of grazing, k being a constant (k = 0.95 x 10(-3) +/- 0.11 x 10(-3) m(-1) Bq g(-1) Ca). The fact that there is less scattering in the relationship for the 90Sr(milk)-altitude than for 90Sr(soil)-altitude suggests, again, that milk is a well-suited sample for environmental survey. The relationship between the altitude of grazing and the 90Sr content of milk and cheese can also be used to assess the authenticity of dairy products. PMID:17005236

  20. Will blocking historical drainage ditches increase carbon sequestration in upland blanket mires of Southwest England?

    NASA Astrophysics Data System (ADS)

    Le Feuvre, N.; Hartley, I.; Anderson, K.; Luscombe, D.; Grand-Clement, E.; Smith, D.; Brazier, R.

    2012-04-01

    Peat soils in the United Kingdom are estimated to store a minimum of 3,121Mt C (Lindsay, 2010). Despite being such a large carbon store the annual imbalance between uptake and release is small and susceptible to change in response to land management, atmospheric deposition and climate change. The upland blanket mires of Southwest England have been subject to extensive drainage and are particularly vulnerable to climate change as they lie at the lower edge of the peatland climatic envelope. The Mires-on-the-Moors project, funded by South West Water will restore over 2000 hectares of drained mire by April 2015. Herein, we question whether this restoration, which will block historical drainage ditches will allow the blanket bogs of Exmoor and Dartmoor National Parks to recover their ecohydrological functionality. We hypothesise that such mire restoration will increase the resilience of these ecosystems to climate change and will return these upland mires to peat forming/carbon sequestering systems. A method is proposed which aims to understand the processes driving gaseous carbon exchange and peat formation in an upland blanket bog and quantifies the effect restoration has on these processes. We propose to measure the spatial variation in gas fluxes with respect to structural features of the mire; drainage ditches and nanotopes. The role of vegetation; the community composition, phenology and health will be explored as well as environmental variables such as water table depths, temperature and photosynthetically active radiation. Importantly, the experiment will partition below ground respiration to assess the environmental controls and effect of restoration on autotrophic and heterotrophic respiration separately. Unusually, it will be possible to collect both pre- and post-restoration data for two experimental sites with existing intensive hydrological monitoring (baseline monitoring of water table depths at 15 minute timesteps has been in place for > 1 year at ca. 160 locations across two experimental catchments on Exmoor). Remote sensing of vegetation structure (using both airborne LiDAR and ground-based laser scanning tools) alongside geospatial modelling will enable the effects of restoration on carbon storage to be modelled from headwater catchment to moorland scales. Lindsay, R. (2010) Peatbogs and Carbon: A Critical Synthesis. University of East London, London.

  1. Peat resource evaluation, State of Maine. Peat program. Final report: Phase Two

    SciTech Connect

    Not Available

    1982-02-01

    This final report for Phase Two of the Peat Resource Evaluation Program in Maine summarizes the results of the second year of a three-year program to document Maine's peat resources. Fifty peat deposits, were measured and sampled in Piscataquis, Somerset, Aroostook, Kennebec, and Waldo Counties. From measurements collected in the field and from surface area measured on topographic maps and air photographs, the total amount of commercial peat resources investigated this past season was approximately 24,000,000 tons of air-dried commercial quality peat. These deposits range in size from 44 acres to 1344 acres, and contain from 50,000 to 3,200,000 short tons of air dried peat. Approximately 470 peat samples were collected during the 1980 field season. Approximately one hundred and twenty samples were sent to the US Geological Survey laboratories for percent of ash and moisture as received, as well as pH and some trace element content. Proximate and ultimate analysis and calorific values of an additional 300 samples were obtained at the US Department of Energy laboratories in Grand Forks, North Dakota. The Plant and Soil Sciences Department at the University of Maine at Orono determined the bulk density of 40 samples. Final peat distribution maps for six counties in Maine - Aroostook, Penobscot, Piscataquis, Hancock, Somerset, and Washington - have been prepared and are enclosed with this report. These maps include information on the location, physiographic form, aerial extent, and commercial quality resources of the surveyed peat deposits.

  2. Influence of Soil Structure, Pore-Water Pressure, and Tailwater Height on Headcut Migration in Upland Concentrated Flows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil loss from arable fields caused by surface runoff erosion is composed of several components due to different erosion processes. Bennett et al. (2000) reported experimental data showing that actively migrating ephemeral-gully headcuts display steady-state migration and self-similar organization i...

  3. Chromate reduction on humic acid derived from a peat soil--exploration of the activated sites on HAs for chromate removal.

    PubMed

    Huang, S W; Chiang, P N; Liu, J C; Hung, J T; Kuan, W H; Tzou, Y M; Wang, S L; Huang, J H; Chen, C C; Wang, M K; Loeppert, R H

    2012-05-01

    Humic substances are a major component of soil organic matter that influence the behavior and fate of heavy metals such as Cr(VI), a toxic and carcinogenic element. In the study, a repetitive extraction technique was used to fractionate humic acids (HAs) from a peat soil into three fractions (denoted as F1, F2, and F3), and the relative importance of O-containing aromatic and aliphatic domains in humic substances for scavenging Cr(VI) was addressed at pH 1. Spectroscopic analyses indicated that the concentrations of aromatic C and O-containing functional groups decreased with a progressive extraction as follows: F1>F2>F3. Cr(VI) removal by HA proceeded slowly, but it was enhanced when light was applied due to the production of efficient reductants, such as superoxide radical and H(2)O(2), for Cr(VI). Higher aromatic- and O-containing F1 fraction exhibited a greater efficiency for Cr(VI) reduction (with a removal rate of ca. 2.89 mmol g(-1) HA under illumination for 3 h). (13)C NMR and FTIR spectra further demonstrated that the carboxyl groups were primarily responsible for Cr(VI) reduction. This study implied the mobility and fate of Cr(VI) would be greatly inhibited in the environments containing such organic groups. PMID:22309710

  4. 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.

  5. Chemical properties of peat used in balneology

    NASA Astrophysics Data System (ADS)

    Szajdak, L.; H?ado?, T.

    2009-04-01

    The physiological activity of peats is observed in human peat-bath therapy and in the promotion of growth in some plants. Balneological peat as an ecologically clean and natural substance is perceived as being more 'human friendly' than synthetic compounds. Poland has a long tradition of using balneological peat for therapeutic purposes. Balneological peat reveals a physical effect by altering temperature and biochemical effects through biologically active substances. It is mainly used for the treatment of rheumatic diseases that are quite common in Poland. Peat represents natural product. Physico-chemical properties of peat in particular surface-active, sorption and ion exchanges, defining their biological function, depend mainly on the chemical composition and molecular structure of humic substances representing the major constituent of organic soil (peat). The carbon of organic matter of peats is composed of 10 to 20% carbohydrates, primarily of microbial origin; 20% nitrogen-containing constituents, such as amino acids and amino sugars; 10 to 20% aliphatic fatty acids, alkanes, etc.; with the rest of carbon being aromatic. For balneology peat should be highly decomposed (preferably H8), natural and clean. The content of humic acids should exceed 20% of dry weight, ash content will be less than 15 15% of dry weight, sulphur content less than 0.3% of dry weight and the amount of water more than 85%. It will not contain harmful bacteria and heavy metals. Humic substances (HS) of peat are known to be macromolecular polydisperse biphyllic systems including both hydrophobic domains (saturated hydrocarbon chains, aromatic structural units) and hydrophilic functional groups, i. e having amphiphilic character. Amphiphilic properties of FA are responsible for their solubility, viscosity, conformation, surfactant-like character and a variety of physicochemical properties of considerable biologically practical significance. The chemical composition of peats depends significantly on the genesis of peatlands and the depth of sampling. The chemical properties of peat fulvic acids (FA) have some genetic peculiarities due to the specific conditions of the process of humification of peat-forming plants in mires. The process of humification in mires takes place in the top-forming layer under amphibious moisture conditions. Substances of microbial origin are water-soluble and can participate in the formation of peat FA to a little extent. So a main source of structural units for the peat HA and FA is suggested to be organic constituents of peat forming plants of various botanical composition. The content of aromatic units in peat FA was shown to depend on the content of lignin in peat-forming plants and also of the aromatization of polysaccharides mainly due to the transformation of cellulose. FA characterized lower than humic acids molecular weight (1000-30,000). FA's are composed of a series of highly oxidized aromatic rings with a large number of side chains. Building blocks are benzene carboxylic acids and phenolic acids. These are held together by hydrogen bonding van der Waals' forces and ionic bonding. FA contains larger concentrations of nitrogen. This fraction also contains a great deal of polysaccharide materials, as well as low molecular fatty acids and cytoplasmic constituents of microorganisms. These compounds are linear, flexible colloids at low concentrations, and spherical colloids at high solution concentrations and low pH values. A more adequate knowledge of the chemical structure of humic materials will assist us in better understanding the physiological effects and also the function of these macromolecules on the health that these materials are know to exert. This improved knowledge provides us better information on chemical structure of humic substances from peats, which are responsible for pharmacotherapeutic, pharmacokinetic and biopharmaceutical effect. This structure of FA creates proper conditions for uptake of nutrient as well as bioavailability of biologically active substances. The solubilization in water by

  6. Impact of fire on macropore flow and the hydraulic conductivity of near-surface blanket peat

    NASA Astrophysics Data System (ADS)

    Holden, Joseph; Wearing, Catherine; Palmer, Sheila; Jackson, Benjamin; Johnston, Kerrylyn; Brown, Lee

    2013-04-01

    Peatlands can be subject to wildfire or deliberate burning in many locations. Wildfires are known to impact soil properties and runoff production in most soil types but relatively little work has been conducted on peatlands. Furthermore in large parts of the UK uplands prescribed vegetation burning on peat has taken place at regular intervals (e.g. every 8-25 years) on patches of around 300-900 sq. metres over the past century to support increased grouse populations for sport shooting. However, there have been few studies on how these prescribed fires influence near-surface hydrology. It is known that macropores transport a large proportion of flow in near-surface peat layers and we investigated their role in flow transport for fire sites using tension infiltrometers. Measurements were performed, at replicated hillslope positions to control for slope position effects, on unburnt peat (U) and where prescribed burning had taken place two years (P2), four years (P4) and >15 years (P15+) prior to sampling. For the prescribed burning plots, vegetation burning had also occurred at around a 15-20 year interval for most of the past century. We also sampled a nearby wildfire site (W) with the same sampling design where wildfire had occurred four months prior to sampling. Both the contribution of macropore flow to overall infiltration, and the saturated hydraulic conductivity, were significantly lower in the recently burnt sites (W, P2, P4), compared to P15+ and U. There was no significant difference in macropore flow contributions, effective macroporosity and saturated hydraulic conductivity between P15+ and U. The results suggest fire influences the near-surface hydrological functioning of peatlands but that 'recovery' for some hydrological processes to prescribed vegetation burning may be possible within two decades if there are no further fires.

  7. Geochemical and Hydrological limitation of carbon sequestration and methane release in anoxic peat soil from the Luther Marsh, Canada

    NASA Astrophysics Data System (ADS)

    Bonaiuti, Simona; Blodau, Christian

    2015-04-01

    In deep peat layers, anaerobic respiration showed a slow-down due to the lack of solute transport which causes an accumulation of metabolic end products (i.e. DIC and CH4). This accumulation can lower the Gibbs free energy levels available to the terminal respiration processes, potentially leading to an inhibition in the decomposition. In particular, this state can affect the methanogenesis, acetogenesis and fermentation processes which occur near thermodynamic minimum energy levels. We conducted a column experiments with an ombrothrophic bog peat over a period of 300 days at 20° C, to test the hypothesis that alteration in solute and gas transport rates can remove this biogeochemical inactivation of DIC and methane turnover rates. To this end, we tested a i) control treatment with no gas and solute transport, ii) advective flow treatment with a flow water of 10 mm d-1, iii) ebullition treatment with methane removal by conduit transport as surrogate for bubbling, and iv) an O2-free atmosphere treatment to test the effect of remote transport of electron on anaerobic decomposition, in absence of oxygen compared to the other treatment. We determined detailed concentration depth profiles of dissolved inorganic carbon (DIC), methane (CH4) and relevant decomposition intermediates (i.e. H2, Fe, nitrate, acetate, formiate and propionate), every 15 days at the beginning and every ca. 2 months after 75 days. CO2 and CH4 fluxes were measured using a static chamber approach. Net turnover of DIC and CH4 in depth layers was calculated for individual depth intervals from mass balance approach based on diffusive mass fluxes between adjacent depth layers and change in storage over time. Thermodynamic energy levels of relevant electron accepting processes were calculated over time. In the initial phase of the experiments, DIC and CH4 concentrations increased mostly below the water table level at 10 cm depth and over time in all treatments. After 45 days of incubation, CH4 concentrations strongly increased in the advective flow treatment, peaked at 70 cm depth with 700 ?mol L-1, and in the O2-free treatment, peaked at 20 cm depth with ca. 600 ?mol L-1. DIC concentrations after 45 days showed similar pattern in term of levels between the different treatments, showed an increase from ca. 3000 ?mol L-1 near the water table to about 5000-6000 ?mol L-1at 70-75 cm depth. Furthermore, DIC and methane concentrations in the ebullition treatment showed a decline over time, probably due to the export of gases through the formation of bubbles. At the end of the experiment, we expect that a negative feedback on decomposition will mostly occur in deeper layers in the control treatments due to the slowness of transport and where the accumulation of CO2 and CH4 will be eased, in line with the results presented in previous studies. Keywords: Peatlands; Anaerobic decomposition; Methanogenesis; Net turnover rates; Gas fluxes; Advection; Ebullition.

  8. 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

  9. 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.

  10. Minerals Yearbook, 1989: Peat

    SciTech Connect

    Cantrell, R.L.

    1990-10-01

    U.S. peat demand peaked at 1.5 million tons in 1987, following a 4-year period of record growth. Demand improved by an average of 12% per year during the period, eclipsing previous records. Growth in domestic production was also strong, increasing at an average annual rate of 9%. The following topics relating to peat, are discussed in the report: Domestic Data Coverage; Production; Consumption and Uses; Stocks; Prices; Foreign Trade; World Review; Current Research; Outlook; Background.

  11. 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)

  12. 77 FR 19925 - Upland Cotton Base Quality

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-03

    ...7 CFR Part 1427 RIN 0560-AI16 Upland Cotton Base Quality AGENCY: Commodity Credit...Commodity Credit Corporation (CCC) upland cotton marketing assistance loan (MAL) regulations...uses base quality to calculate upland cotton loan rates, Adjusted World Price...

  13. Spatial analysis of soil subsidence in peat meadow areas in Friesland in relation to land and water management, climate change, and adaptation.

    PubMed

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

    2015-02-01

    Dutch peatlands have been subsiding due to peat decomposition, shrinkage and compression, since their reclamation in the 11th century. Currently, subsidence amounts to 1-2 cm/year. Water management in these areas is complex and costly, greenhouse gases are being emitted, and surface water quality is relatively poor. Regional and local authorities and landowners responsible for peatland management have recognized these problems. In addition, the Netherlands Royal Meteorological Institute predicts higher temperatures and drier summers, which both are expected to enhance peat decomposition. Stakeholder workshops have been organized in three case study areas in the province of Friesland to exchange knowledge on subsidence and explore future subsidence rates and the effects of land use and management changes on subsidence rates. Subsidence rates were up to 3 cm/year in deeply drained parcels and increased when we included climate change in the modeling exercises. This means that the relatively thin peat layers in this province (ca 1 m) would shrink or even disappear by the end of the century when current practices continue. Adaptation measures were explored, such as extensive dairy farming and the production of new crops in wetter conditions, but little experience has been gained on best practices. The workshops have resulted in useful exchange of ideas on possible measures and their consequences for land use and water management in the three case study areas. The province and the regional water board will use the results to develop land use and water management policies for the next decades. PMID:25351830

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

    NASA Astrophysics Data System (ADS)

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

    2015-02-01

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

  15. 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)

  16. Peat resource estimation in South Carolina. Second quarterly report (year 2)

    SciTech Connect

    Cohen, Dr., A. D.; Tisdale, M.; Andrejko, M.; Corvinus, D.; Knight, Richard A.; Olsen, N. K.; Vigerstad, Dr., T. J.

    1981-04-01

    The objectives of this program are to assess the magnitude of the resources and locate areas of highest potential for peat deposits in South Carolina. The energy potential of these peat resources is also being evaluated. This report presents the results of progress made during the last quarter in: assessing data and prioritizing peat areas to be surveyed; procurement of equipment and supplies; and preliminary peat resource assessment. A summary of the results of all new field surveys conducted during the quarter is included. Approximate locations of potential major peat deposits have been identified. Preliminary sampling studies indicate that Pigeon Bay may have the thickest and best quality peat in Berkeley County. Probes indicate peats up to 12 feet thick are located near the Black River in Georgetown County. Samples from areas designated as organic soils by the USDA were analyzed for moisture, organic, and ash content. (DMC)

  17. Diurnal and seasonal patterns of ecosystem CO{sub 2} efflux from upland tundra in the foothills of the Brooks Range, Alaska, U.S.A.

    SciTech Connect

    Oberbauer, S.F.; Gillespie, C.T.; Cheng, Weixin

    1996-08-01

    Carbon dioxide efflux and soil microenvironment were measured in three upland tundra communities in the foothills of the Brooks Range in arctic Alaska to determine the magnitude of CO{sub 2} efflux rates and the relative importance of the belowground factors that influence them. Gas exchange and soil microenvironment measurements were made weekly between 14 June and 31 July 1990. The study communities included lichen-heath, a sparse community vegetated by lichens and dwarf ericaceous shrubs on rocky soils, moist Cassiope dwarf-shrub heath tundra, dominated by Carex and evergreen and deciduous shrubs on relatively deep organic soils, and dry Cassiope dwarf-shrub heath of stone-stripe areas, which was of intermediate character. Rates of CO{sub 2} efflux were similar for the three communities until mid-season when they peaked at rates between 4.9 and 5.9 g m{sup {minus}2} d{sup {minus}1}. Following the mid-season peak, the rates in all three communities declined, particularly in the lichen-heath. Seasonal patterns of CO{sub 2} efflux, soil temperature, and soil moisture suggest changing limitations to CO{sub 2} efflux, soil temperature, and soil moisture suggest changing limitations to CO{sub 2} efflux over the course of the season. Rates of carbon dioxide efflux followed changes in soil temperature early in the season when soil moisture was highest. Mid-season efflux appeared to be limited by soil, moss, and lichen hydration until the end of July, when temperature again limited efflux. Differences between the communities were related to microenvironmental differences and probable differences in carbon quality. The presence of peat-forming mosses is suggested to play an important role in differences in efflux and micro-environment among the communities. 32 refs., 3 figs., 4 tab.

  18. 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.

  19. Peat carbon stocks and potential microbial lability of boreal peatlands with varying permafrost histories

    NASA Astrophysics Data System (ADS)

    Olefeldt, D.; Pelletier, N.; Talbot, J.; Blodau, C.; Turetsky, M. R.

    2014-12-01

    Large stores of C in the form of peat are stored in permafrost, particularly in the boreal discontinuous permafrost zone. Ongoing climate change is causing widespread permafrost thaw in boreal peatlands, a trend which is expected to continue this century and thus make large stores of soil C available for microbial processes and mineralization. Permafrost thaw in boreal peatlands is often associated with an ecosystem shift from dry peat plateau to wet bog surfaces, and the net C balance following thaw is determined by the balance between the mineralization of plateau peat and the new accumulation of bog peat on top. In this study we collected soil cores (~3 m deep) from one peat plateaus and four bogs that differed in time since thaw (approximately 10, 50 and 500 years since thaw). In order to assess the potential microbial lability, we incubated 25 soil samples from each core under aerobic conditions at 17.5 deg C. Mineralization rates were 1-2 order of magnitude higher near the surface than at depth, but near surface samples also had high variability among cores. Variability in peat microbial lability near the surface was related to thaw history and to differences in characteristics between plateau and bog peat. Mineralization rates of peat samples from below 1 m depth and down to the interface with mineral soil at 3 m were consistently low and had no difference among cores. Mineralization rates during the first 3 months of incubation for deep plateau peat samples were equivalent to 1% soil C losses per year. Relatively low microbial lability of deep peat in combination with high rates of new peat accumulation during the initial stages of bog development suggests that there is net C accumulation immediately following thaw but that the sink strength weakens or reverses during later stages when new accumulation rates diminish.

  20. 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.

  1. The effect of fire and permafrost interactions on soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: Implications for post-thaw carbon loss

    USGS Publications Warehouse

    O'Donnell, J. A.; Harden, J.W.; McGuire, A.D.; Kanevskiy, M.Z.; Jorgenson, M.T.; Xu, X.

    2011-01-01

    High-latitude regions store large amounts of organic carbon (OC) in active-layer soils and permafrost, accounting for nearly half of the global belowground OC pool. In the boreal region, recent warming has promoted changes in the fire regime, which may exacerbate rates of permafrost thaw and alter soil OC dynamics in both organic and mineral soil. We examined how interactions between fire and permafrost govern rates of soil OC accumulation in organic horizons, mineral soil of the active layer, and near-surface permafrost in a black spruce ecosystem of interior Alaska. To estimate OC accumulation rates, we used chronosequence, radiocarbon, and modeling approaches. We also developed a simple model to track long-term changes in soil OC stocks over past fire cycles and to evaluate the response of OC stocks to future changes in the fire regime. Our chronosequence and radiocarbon data indicate that OC turnover varies with soil depth, with fastest turnover occurring in shallow organic horizons (~60 years) and slowest turnover in near-surface permafrost (>3000 years). Modeling analysis indicates that OC accumulation in organic horizons was strongly governed by carbon losses via combustion and burial of charred remains in deep organic horizons. OC accumulation in mineral soil was influenced by active layer depth, which determined the proportion of mineral OC in a thawed or frozen state and thus, determined loss rates via decomposition. Our model results suggest that future changes in fire regime will result in substantial reductions in OC stocks, largely from the deep organic horizon. Additional OC losses will result from fire-induced thawing of near-surface permafrost. From these findings, we conclude that the vulnerability of deep OC stocks to future warming is closely linked to the sensitivity of permafrost to wildfire disturbance. ?? 2010 Blackwell Publishing Ltd.

  2. 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 ...

  3. Characterization of heterotrophic nitrifying bacteria with respiratory ammonification and denitrification activity--description of Paenibacillus uliginis sp. nov., an inhabitant of fen peat soil and Paenibacillus purispatii sp. nov., isolated from a spacecraft assembly clean room.

    PubMed

    Behrendt, Undine; Schumann, Peter; Stieglmeier, Michaela; Pukall, Rüdiger; Augustin, Jürgen; Spröer, Cathrin; Schwendner, Petra; Moissl-Eichinger, Christine; Ulrich, Andreas

    2010-10-01

    In the course of studying the influence of N-fertilization on N(2) and N(2)O flux rates in relation to soil bacterial community composition of a long-term fertilization experiment in fen peat grassland, a strain group was isolated that was related to a strain isolated from a spacecraft assembly clean room during diversity studies of microorganisms, which withstood cleaning and bioburden reduction strategies. Both the fen soil isolates and the clean room strain revealed versatile physiological capacities in N-transformation processes by performing heterotrophic nitrification, respiratory ammonification and denitrification activity. Phylogenetic analysis based on 16S rRNA gene sequences demonstrated that the investigated isolates belonged to the genus Paenibacillus. Sequence similarities lower than 97% in comparison to established species indicated a separate species position. Except for the peptidoglycan type (A4alpha L-Lys-D-Asp), chemotaxonomic features of the isolates matched the genus description, but differences in several physiological characteristics separated them from related species and supported their novel species status. Despite a high 16S rRNA gene sequence similarity between the clean room isolate ES_MS17(T) and the representative fen soil isolate N3/975(T), DNA-DNA hybridization studies revealed genetic differences at the species level. These differences were substantiated by MALDI-TOF MS analysis, ribotyping and several distinct physiological characteristics. On the basis of these results, it was concluded that the fen soil isolates and the clean room isolate ES_MS17(T) represented two novel species for which the names Paenibacillus uliginis sp. nov. (type strain N3/975(T)=DSM 21861(T)=LMG 24790(T)) and Paenibacillus purispatii sp. nov. (type strain ES_MS17(T)=DSM 22991(T)=CIP 110057(T)) are proposed. PMID:20813476

  4. 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.

  5. 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 different manners. Interactions between climate change and land management shifts will also be taken into account. The modelling results will be beneficial for the planning of land-use strategies in the blanket peatlands across the world.

  6. 46 CFR 148.290 - Peat moss.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 2011-10-01 2011-10-01 false Peat moss. 148.290 Section 148.290 Shipping ...Requirements for Certain Materials § 148.290 Peat moss. (a) Before shipment, peat moss must be stockpiled under cover to allow...

  7. 46 CFR 148.290 - Peat moss.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 2012-10-01 2012-10-01 false Peat moss. 148.290 Section 148.290 Shipping ...Requirements for Certain Materials § 148.290 Peat moss. (a) Before shipment, peat moss must be stockpiled under cover to allow...

  8. 46 CFR 148.290 - Peat moss.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 2014-10-01 2014-10-01 false Peat moss. 148.290 Section 148.290 Shipping ...Requirements for Certain Materials § 148.290 Peat moss. (a) Before shipment, peat moss must be stockpiled under cover to allow...

  9. 46 CFR 148.290 - Peat moss.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 2013-10-01 2013-10-01 false Peat moss. 148.290 Section 148.290 Shipping ...Requirements for Certain Materials § 148.290 Peat moss. (a) Before shipment, peat moss must be stockpiled under cover to allow...

  10. Quantitative trait locus analysis of Verticillium wilt resistance in an introgressed recombinant inbred population of Upland cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Verticillium wilt (VW) of Upland cotton (Gossypium hirsutum L.) is caused by the soil-borne fungal pathogen Verticillium dahlia Kleb. The availability of VW-resistant cultivars is vital for control of this economically important disease, but there is a paucity of Upland cotton breeding lines and cul...

  11. Biochemical processes of oligotrophic peat deposits of Vasyugan Mire

    NASA Astrophysics Data System (ADS)

    Inisheva, L. I.; Sergeeva, M. A.

    2009-04-01

    The problem of peat and mire ecosystems functioning and their rational use is the main problem of biosphere study. This problem also refers to forecasting of biosphere changes results which are global and anthropogenic. According to many scientists' research the portion of mires in earth carbon balance is about 15% of world's stock. The aim of this study is to investigate biochemical processes in oligotrophic deposits in North-eastern part of Vasyugan Mire. The investigations were made on the territory of scientific-research ground (56Ë? 03´ and 56Ë? 57´ NL, 82Ë? 22´ and 82Ë? 42´ EL). It is situated between two rivers Bakchar and Iksa (in outskirts of the village Polynyanka, Bakchar region, Tomsk oblast). Evolution of investigated mire massif began with the domination of eutrophic phytocenosis - Filicinae, then sedge. Later transfer into oligotrophic phase was accompanied by formation of meter high-moor peat deposit. The age of three-meter peat deposit reaches four thousand years. Biochemical processes of carbon cycle cover the whole peat deposit, but the process activity and its direction in different layers are defined by genesis and duration of peat formation. So, the number of cellulose-fermenting aerobes in researched peat deposits ranges from 16.8 to 75.5 million CFU/g, and anaerobic bacteria from 9.6 to 48.6 million CFU/g. The high number of aerobes is characteristic for high water levels, organizing by raised bog peats. Their number decreases along the profile in 1.7 - 2 times. The number of microflora in peat deposit is defined by the position in the landscape profile (different geneses), by the depth, by hydrothermic conditions of years and individual months. But microflora activity shows along all depth of peat deposit. We found the same in the process of studying of micromycete complex structure. There was revealed either active component micromycete complex - mycelium, or inert one - spores in a meter layer of peat deposit. If mushrooms spores are observed in all deposit layers, mycelium of mushrooms deepens into the peat deposit (to 2 meters) within the limits of aerobic (meter) zone and only in particular months of dry years. The existence of seasonal dynamics of eukaryotic cells, and also capability of yeast and other groups of micromycetes for growth, testifies about vital activity of a number of eukaryotic cells at a depth of 2 meters. Researched peat deposits are biochemically active along the whole profile. But they are different in a microflora number of individual physiological groups either in items of the landscape, or in deposit depth. The largest quantity of aerobic cellulose-fermenting microorganisms is marked during dry years. Anaerobic cellulose-fermenting microorganisms dominate during wet years. The quantity of microbe biomass increases in bottom lifts of peat deposits. This fact testifies about viable condition of microbe complex at depth. The formation process of carbon dioxide in peat deposits of Vasyugan Mire actively occurs during dry years and is defined by hydrothermic conditions of a meter layer of peat deposit. The intensity of CO2 isolation for certain correlates with the temperature in horizon of 0 - 50 sm. and with bog waters level. The study of gas composition for the three years showed that the largest concentration of carbon dioxide in peat soils is marked along the whole profile during a dryer year (0.08 - 2.65 millimole/l), increasing other years' level in about 1.5 0 2 times. Emission of carbon dioxide in peat

  12. Explosive silicic eruptions in Iceland: from vent to peat bog

    E-print Network

    Explosive silicic eruptions in Iceland: from vent to peat bog OUTLINE Microtephra horizons, found in soils across Scotland, contain fine ash produced by explosive eruptions in Iceland. They represent; Thordarson & Larsen 2007), but vary in size and explosivity. The primary threat to Scotland from the tephra

  13. Peat Characterization and Uptake of Nickel (II) and Cobalt (II) in a Saprist Peat E. S. Asapo1, 2*

    E-print Network

    Coles, Cynthia

    + and their complexes are toxic and possible human carcinogens (IARC, 1990) and their efficient removal during metal Treatment of wastewaters containing toxic metals remains a persistent environmental issue and no method or fibrist peat soils have emerged as strong adsorbents for heavy metals such as Pb, Cu and Ni (Ho et al

  14. 7 CFR 1205.13 - Upland cotton.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Upland cotton. 1205.13 Section 1205.13 Agriculture...COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Procedures for...Period Definitions § 1205.13 Upland cotton. The term Upland cotton means...

  15. 7 CFR 1205.13 - Upland cotton.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Upland cotton. 1205.13 Section 1205.13 Agriculture...COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Procedures for...Period Definitions § 1205.13 Upland cotton. The term Upland cotton means...

  16. 7 CFR 1205.13 - Upland cotton.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Upland cotton. 1205.13 Section 1205.13 Agriculture...COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Procedures for...Period Definitions § 1205.13 Upland cotton. The term Upland cotton means...

  17. 7 CFR 1205.13 - Upland cotton.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Upland cotton. 1205.13 Section 1205.13 Agriculture...COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Procedures for...Period Definitions § 1205.13 Upland cotton. The term Upland cotton means...

  18. 7 CFR 1205.13 - Upland cotton.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Upland cotton. 1205.13 Section 1205.13 Agriculture...COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Procedures for...Period Definitions § 1205.13 Upland cotton. The term Upland cotton means...

  19. 7 CFR 1205.305 - Upland cotton.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Upland cotton. 1205.305 Section 1205.305 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions § 1205.305 Upland cotton. Upland cotton means all...

  20. 7 CFR 1205.305 - Upland cotton.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Upland cotton. 1205.305 Section 1205.305 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions § 1205.305 Upland cotton. Upland cotton means all...

  1. 7 CFR 1205.13 - Upland cotton.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Upland cotton. 1205.13 Section 1205.13 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Procedures for Conduct of Sign-up Period Definitions § 1205.13 Upland cotton. The term Upland cotton...

  2. 7 CFR 1205.13 - Upland cotton.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Upland cotton. 1205.13 Section 1205.13 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Procedures for Conduct of Sign-up Period Definitions § 1205.13 Upland cotton. The term Upland cotton...

  3. 7 CFR 1205.13 - Upland cotton.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Upland cotton. 1205.13 Section 1205.13 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Procedures for Conduct of Sign-up Period Definitions § 1205.13 Upland cotton. The term Upland cotton...

  4. 7 CFR 1205.305 - Upland cotton.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Upland cotton. 1205.305 Section 1205.305 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions § 1205.305 Upland cotton. Upland cotton means all...

  5. 7 CFR 1205.13 - Upland cotton.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Upland cotton. 1205.13 Section 1205.13 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Procedures for Conduct of Sign-up Period Definitions § 1205.13 Upland cotton. The term Upland cotton...

  6. 7 CFR 1205.305 - Upland cotton.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Upland cotton. 1205.305 Section 1205.305 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions § 1205.305 Upland cotton. Upland cotton means all...

  7. 7 CFR 1205.305 - Upland cotton.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Upland cotton. 1205.305 Section 1205.305 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions § 1205.305 Upland cotton. Upland cotton means all...

  8. 7 CFR 1205.13 - Upland cotton.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Upland cotton. 1205.13 Section 1205.13 Agriculture... AND ORDERS; MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Procedures for Conduct of Sign-up Period Definitions § 1205.13 Upland cotton. The term Upland cotton...

  9. Uplands and Land Use Decision Making.

    ERIC Educational Resources Information Center

    Smith, Dwight G.

    This material includes student guide sheets, reference material, and tape script for the audio-tutorial unit on uplands. A set of 35mm slides and an audio tape are used with the materials. The material is designed for use with Connecticut schools, but can be adapted to other localities. The materials consider types of uplands, ecology of uplands,…

  10. Climate sensitivity and macronutrient regulation of peat decomposition

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

    Organic soils act as vital global carbon stores maintained in northern latitudes by climate and nutrient limited rates of organic matter decomposition. Peatland decomposition rates are sensitive to climate change, however predicting the magnitude of the microbial respiratory response is complex due to unknown interactions between climate and substrate quality. The nutrient status of peatlands varies widely from mineral rich fens to nutrient poor ombrotrophic bogs, which have the potential to respond differently to climate driven changes in temperature and carbon (C) inputs. In this work we examine the links between peatland macronutrient C, phosphorus (P) and nitrogen (N) stoichiometry, microbial community structure and the microbial response to direct and indirect effects of climate change. Using total soil C:N and C:P ratios to define nutrient gradients in organic soils from Svalbard and Finland we investigated the interaction between the microbial response to temperature and nutrient limitation of decomposition. In organic rich soils from Svalbard we found there was a significant relationship between increasing temperature sensitivity of respiration and decreasing total soil P concentrations. Further investigation of the potential direct link between P limitation of decomposition and increased temperature sensitivity along a minerotrophic-ombroptrophic gradient in Finland was performed using multi-factorial P limitation assays. These showed that despite varying degrees of P limitation across four peatland soils there was no relationship between P limitation and increased temperature sensitivity of soil respiration. Throughout this study we found consistently high temperature sensitivity of decomposition in organic rich soils with Q10 values ranging between 2 to 4.5, indicating potentially higher vulnerability of these C stores to warming than is currently predicted using a globally invariant Q10. Following on from this we examined the interaction between 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.

  11. 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)

  12. 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.

  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. 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

  15. Short-column anion-exchange chromatography for soil and peat humic substances profiling by step-wise gradient of high pH aqueous sodium ethylenediaminetetraacetate.

    PubMed

    Hutta, Milan; Ráczová, Janka; Góra, Róbert; Pessl, Juraj

    2015-08-21

    Novel anion-exchange liquid chromatographic method with step gradient of aqueous EDTA(4-) based mobile phase elution has been developed to profile available Slovak soil humic substances and alkaline extracts of various soils. The method utilize short glass column (30mm×3mm) filled in with hydrolytically stable particles (60?m diameter) Separon HEMA-BIO 1000 having (diethylamino)ethyl functional groups. Step gradient was programmed by mixing mobile phase composed of aqueous solution of sodium EDTA (pH 12.0; 5mmolL(-1)) and mobile phase constituted of aqueous solution of sodium EDTA (pH 12.0, 500mmolL(-1)). The FLD of HSs was set to excitation wavelength 480nm and emission wavelength 530nm (?em). Separation mechanism was studied by use of selected aromatic acids related to humic acids with the aid of UV spectrophotometric detection at 280nm. The proposed method benefits from high ionic strength (I=5molL(-1)) of the end mobile phase buffer and provides high recovery of humic acids (98%). Accurate and reproducible profiling of studied humic substances, alkaline extracts of various types of soils enables straightforward characterization and differentiation of HSs in arable and forest soils. Selected model aromatic acids were used for separation mechanism elucidation. PMID:26143606

  16. 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.

  17. 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.

  18. 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.

  19. 7 CFR 319.69-5 - Types of soil authorized for packing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...Materials Rules and Regulations § 319.69-5 Types of soil authorized for packing. The following types of soil or earth are authorized as safe for packing: (a) Peat, (b) peat moss, and (c) Osmunda...

  20. 7 CFR 319.69-5 - Types of soil authorized for packing.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...Materials Rules and Regulations § 319.69-5 Types of soil authorized for packing. The following types of soil or earth are authorized as safe for packing: (a) Peat, (b) peat moss, and (c) Osmunda...

  1. 7 CFR 319.69-5 - Types of soil authorized for packing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...Materials Rules and Regulations § 319.69-5 Types of soil authorized for packing. The following types of soil or earth are authorized as safe for packing: (a) Peat, (b) peat moss, and (c) Osmunda...

  2. 7 CFR 319.69-5 - Types of soil authorized for packing.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...Materials Rules and Regulations § 319.69-5 Types of soil authorized for packing. The following types of soil or earth are authorized as safe for packing: (a) Peat, (b) peat moss, and (c) Osmunda...

  3. Understanding fine sediment and phosphorous delivery in upland catchments

    NASA Astrophysics Data System (ADS)

    Perks, M. T.; Reaney, S. M.

    2013-12-01

    The uplands of UK are heavily impacted by land management including; farming and forestry operations, moorland burning, peat extraction, metal mining, artificial drainage and channelisation. It has been demonstrated that such land management activity may modify hillslope processes, resulting in enhanced runoff generation and changing the spatial distribution and magnitude of erosion. Resultantly, few upland river systems of the UK are operating in a natural state, with land management activity often resulting in increased fluxes of suspended sediment (< 2 mm) and associated pollutants (such as phosphorous). Most recent Environment Agency (EA) data reveals that 60% of monitored water bodies within upland areas of the UK are currently at risk of failing the Water Framework Directive (WFD) due to poor ecological status. In order to prevent the continual degradation of many upland catchments, riverine systems and their diverse ecosystems, a range of measures to control diffuse pollution will need to be implemented. Future mitigation options and measures in the UK may be tested and targeted through the EA's catchment pilot scheme; DEFRA's Demonstration Test Catchment (DTC) programmes and through the catchment restoration fund. However, restoring the physical and biological processes of past conditions in inherently sensitive upland environments is extremely challenging requiring the development of a solid evidence base to determine the effectiveness of resource allocation and to enable reliable and transparent decisions to be made about future catchment operations. Such evidence is rarely collected, with post-implementation assessments often neglected. This paper presents research conducted in the Morland sub-catchment of the River Eden within Cumbria; UK. 80% of this headwater catchment is in upland areas and is dominated by improved grassland and rough grazing. The catchment is heavily instrumented with a range of hydro-meteorological equipment. A high-tech monitoring station at the 12.5 km2 outlet provides flow, turbidity, total phosphorous (TP), total reactive phosphorous (TRP), conductivity, temperature and pH measurements at 15-minute intervals. Within this catchment, two additional monitoring stations along adjacent tributaries with catchment areas of 2.3 km2 and 3.8 km2 provide continuous flow and turbidity data with soluble reactive phosphorous and TP collected during storms. Collection and analysis of this data over two full hydrological years has proved effective in; a) producing load estimates; b) producing better assessments of the magnitude and duration of aquatic organisms exposure to detrimental levels of suspended sediment and phosphorous; c) exploring the processes responsible for the delivery and transfer of fine sediment and phosphorous to and from the channel and; d) enhancing our understanding and prediction of the fluvial sediment system. The process understanding achieved using this monitoring framework has facilitated the production of a mitigation plan for the Morland catchment. Following this plan, a range of measures are currently being implemented to reduce the movement of diffuse pollutants across the hillslopes and channels whilst in-stream monitoring continues. The adopted mitigation measures may act as a trial for other upland catchments facing similar pressures.

  4. 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 and impact of environmental conditions on the surfactant properties of humic matter. Amongst the main objectives of the study was the identification of the dependence of the humic acid properties on the composition of original living matter in the peat, especially considering high variability of peat composition in the studied bogs. Despite some correlation between peat botanical composition and properties exist, in general the similarities are much more expressed, thus indicating the significance of microbial decay processes on the properties of humic material. Acknowledgement: Support from a project ResProd

  5. 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

  6. Correlation analysis as a tool to investigate the bioaccessibility of nickel, vanadium and zinc in Northern Ireland soils.

    PubMed

    Palmer, Sherry; Ofterdinger, Ulrich; McKinley, Jennifer M; Cox, Siobhan; Barsby, Amy

    2013-10-01

    Correlation analyses were conducted on nickel (Ni), vanadium (V) and zinc (Zn) oral bioaccessible fractions (BAFs) and selected geochemistry parameters to identify specific controls exerted over trace element bioaccessibility. BAFs were determined by previous research using the unified BARGE method. Total trace element concentrations and soil geochemical parameters were analysed as part of the Geological Survey of Northern Ireland Tellus Project. Correlation analysis included Ni, V and Zn BAFs against their total concentrations, pH, estimated soil organic carbon (SOC) and a further eight element oxides. BAF data were divided into three separate generic bedrock classifications of basalt, lithic arenite and mudstone prior to analysis, resulting in an increase in average correlation coefficients between BAFs and geochemical parameters. Sulphur trioxide and SOC, spatially correlated with upland peat soils, exhibited significant positive correlations with all BAFs in gastric and gastro-intestinal digestion phases, with such effects being strongest in the lithic arenite bedrock group. Significant negative relationships with bioaccessible Ni, V and Zn and their associated total concentrations were observed for the basalt group. Major element oxides were associated with reduced oral trace element bioaccessibility, with Al2O3 resulting in the highest number of significant negative correlations followed by Fe2O3. spatial mapping showed that metal oxides were present at reduced levels in peat soils. The findings illustrate how specific geology and soil geochemistry exert controls over trace element bioaccessibility, with soil chemical factors having a stronger influence on BAF results than relative geogenic abundance. In general, higher Ni, V and Zn bioaccessibility is expected in peat soil types. PMID:23793447

  7. Transport and fate of trifluoroacetate in upland forest and wetland ecosystems

    SciTech Connect

    Likens, G.E.; Tartowski, S.L.; Berger, T.W.

    1997-04-29

    Although trifluoroacetate (TFA), a breakdown product of chlorofluorocarbon replacements, is being dispersed widely within the biosphere, its ecological fate is largely unknown. TFA was added experimentally to an upland, northern hardwood forest and to a small forest wetland ecosystem within the Hubbard Brook Experimental Forest in New Hampshire. Inputs of TFA were not transported conservatively through these ecosystems; instead, significant amounts of TFA were retained within the vegetation and soil compartments. More TFA was retained by the wetland ecosystem than by the upland forest ecosystem. Using simulation modeling, TFA concentrations were predicted for soil and drainage water until the year 2040. 32 refs., 5 figs., 1 tab.

  8. Transport and fate of trifluoroacetate in upland forest and wetland?ecosystems

    PubMed Central

    Likens, G. E.; Tartowski, S. L.; Berger, T. W.; Richey, D. G.; Driscoll, C. T.; Frank, H. G.; Klein, A.

    1997-01-01

    Although trifluoroacetate (TFA), a breakdown product of chlorofluorocarbon replacements, is being dispersed widely within the biosphere, its ecological fate is largely unknown. TFA was added experimentally to an upland, northern hardwood forest and to a small forest wetland ecosystem within the Hubbard Brook Experimental Forest in New Hampshire. Inputs of TFA were not transported conservatively through these ecosystems; instead, significant amounts of TFA were retained within the vegetation and soil compartments. More TFA was retained by the wetland ecosystem than by the upland forest ecosystem. Using simulation modeling, TFA concentrations were predicted for soil and drainage water until the year 2040. PMID:9114018

  9. Blanket peat biome endangered by climate change

    NASA Astrophysics Data System (ADS)

    Gallego-Sala, Angela V.; Colin Prentice, I.

    2013-02-01

    Blanket bog is a highly distinctive biome restricted to disjunct hyperoceanic regions. It is characterized by a landscape covering of peat broken only by the steepest slopes. Plant and microbial life are adapted to anoxia, low pH and low nutrient availability. Plant productivity exceeds soil organic matter decomposition, so carbon is sequestered over time. Unique climatic requirements, including high year-round rainfall and low summer temperatures, make this biome amenable to bioclimatic modelling. However, projections of the fate of peatlands in general, and blanket bogs in particular, under climate change have been contradictory. Here we use a simple, well-founded global bioclimatic model, with climate-change projections from seven climate models, to indicate this biome's fate. We show marked shrinkage of its present bioclimatic space with only a few, restricted areas of persistence. Many blanket bog regions are thus at risk of progressive peat erosion and vegetation changes as a direct consequence of climate change. New areas suitable for blanket bog are also projected, but these are often disjunct from present areas and their location is inconsistently predicted by different climate models.

  10. 7 CFR 1427.103 - Upland cotton Domestic User Agreement.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Upland cotton Domestic User Agreement. 1427.103...LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.103 Upland cotton...

  11. 7 CFR 1427.101 - Eligible upland cotton.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 false Eligible upland cotton. 1427.101 Section 1427.101 Agriculture...LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.101 Eligible upland...

  12. 7 CFR 1427.101 - Eligible upland cotton.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 false Eligible upland cotton. 1427.101 Section 1427.101 Agriculture...LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.101 Eligible upland...

  13. 7 CFR 1427.101 - Eligible upland cotton.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 false Eligible upland cotton. 1427.101 Section 1427.101 Agriculture...LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.101 Eligible upland...

  14. 7 CFR 1427.103 - Upland cotton Domestic User Agreement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Upland cotton Domestic User Agreement. 1427.103...LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.103 Upland cotton...

  15. 7 CFR 1427.103 - Upland cotton Domestic User Agreement.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Upland cotton Domestic User Agreement. 1427.103...LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.103 Upland cotton...

  16. 7 CFR 1427.101 - Eligible upland cotton.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 false Eligible upland cotton. 1427.101 Section 1427.101 Agriculture...LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.101 Eligible upland...

  17. 7 CFR 1427.103 - Upland cotton Domestic User Agreement.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Upland cotton Domestic User Agreement. 1427.103...LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.103 Upland cotton...

  18. 7 CFR 1427.103 - Upland cotton Domestic User Agreement.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Upland cotton Domestic User Agreement. 1427.103...LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.103 Upland cotton...

  19. 7 CFR 1427.101 - Eligible upland cotton.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 false Eligible upland cotton. 1427.101 Section 1427.101 Agriculture...LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.101 Eligible upland...

  20. CANADIAN PEAT HARVESTING AND THE ENVIRONMENT

    E-print Network

    Laval, Université

    ..................................................................................7 4.0 The Value of Wetlands in Our Environment................................................................6 3.0 The Canadian Peat Industry

  1. 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.

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. Pollutants dynamics in a rice field and an upland field during storm events

    NASA Astrophysics Data System (ADS)

    Kim, Jin Soo; Park, Jong-Wha; Jang, Hoon; Kim, Young Hyeon

    2010-05-01

    We investigated the dynamics of pollutants such as total nitrogen (TN), total phosphorous (TP), biochemical oxygen demand (BOD), chemical oxygen demand (COD), and suspended sediment (SS) in runoff from a rice field and an upland field near the upper stream of the Han river in South Korea for multiple storm events. The upland field was cropped with red pepper, sweet potato, beans, and sesame. Runoff from the rice field started later than that from the upland field due to the water storage function of rice field. Unlike the upland field, runoff from the rice field was greatly affected by farmers' water management practices. Overall, event mean concentrations (EMCs) of pollutants in runoff water from the upland field were higher than those from the rice field. Especially, EMCs of TP and SS in runoff water from the upland field were one order of magnitude higher than those from the rice field. This may be because ponding condition and flat geographical features of the rice field greatly reduces the transport of particulate phosphorous associated with soil erosion. The results suggest that the rice field contributes to control particulate pollutants into adjacent water bodies.

  7. 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 included CO2, CO, NOx (NO and NO2), and SO2 concentrations, PM size-distributions, and PM and black carbon mass concentrations. In addition, Teflon-membrane, quartz-fiber, and Teflon-impregnated glass fiber (TIGF) filters followed by XAD-4 cartridges were collected for detailed chemical analysis.

  8. Coarse Woody Debris Increases Microbial Community Functional Diversity but not Enzyme Activities in Reclaimed Oil Sands Soils.

    PubMed

    Kwak, Jin-Hyeob; Chang, Scott X; Naeth, M Anne; Schaaf, Wolfgang

    2015-01-01

    Forest floor mineral soil mix (FMM) and peat mineral soil mix (PMM) are cover soils commonly used for upland reclamation post open-pit oil sands mining in northern Alberta, Canada. Coarse woody debris (CWD) can be used to regulate soil temperature and water content, to increase organic matter content, and to create microsites for the establishment of microorganisms and vegetation in upland reclamation. We studied the effects of CWD on soil microbial community level physiological profile (CLPP) and soil enzyme activities in FMM and PMM in a reclaimed landscape in the oil sands. This experiment was conducted with a 2 (FMM vs PMM) × 2 (near CWD vs away from CWD) factorial design with 6 replications. The study plots were established with Populus tremuloides (trembling aspen) CWD placed on each plot between November 2007 and February 2008. Soil samples were collected within 5 cm from CWD and more than 100 cm away from CWD in July, August and September 2013 and 2014. Microbial biomass was greater (p<0.05) in FMM than in PMM, in July, and August 2013 and July 2014, and greater (p<0.05) near CWD than away from CWD in FMM in July and August samplings. Soil microbial CLPP differed between FMM and PMM (p<0.01) according to a principal component analysis and CWD changed microbial CLPP in FMM (p<0.05) but not in PMM. Coarse woody debris increased microbial community functional diversity (average well color development in Biolog Ecoplates) in both cover soils (p<0.05) in August and September 2014. Carbon degrading soil enzyme activities were greater in FMM than in PMM (p<0.05) regardless of distance from CWD but were not affected by CWD. Greater microbial biomass and enzyme activities in FMM than in PMM will increase organic matter decomposition and nutrient cycling, improving plant growth. Enhanced microbial community functional diversity by CWD application in upland reclamation has implications for accelerating upland reclamation after oil sands mining. PMID:26618605

  9. Coarse Woody Debris Increases Microbial Community Functional Diversity but not Enzyme Activities in Reclaimed Oil Sands Soils

    PubMed Central

    Kwak, Jin-Hyeob; Chang, Scott X.; Naeth, M. Anne; Schaaf, Wolfgang

    2015-01-01

    Forest floor mineral soil mix (FMM) and peat mineral soil mix (PMM) are cover soils commonly used for upland reclamation post open-pit oil sands mining in northern Alberta, Canada. Coarse woody debris (CWD) can be used to regulate soil temperature and water content, to increase organic matter content, and to create microsites for the establishment of microorganisms and vegetation in upland reclamation. We studied the effects of CWD on soil microbial community level physiological profile (CLPP) and soil enzyme activities in FMM and PMM in a reclaimed landscape in the oil sands. This experiment was conducted with a 2 (FMM vs PMM) × 2 (near CWD vs away from CWD) factorial design with 6 replications. The study plots were established with Populus tremuloides (trembling aspen) CWD placed on each plot between November 2007 and February 2008. Soil samples were collected within 5 cm from CWD and more than 100 cm away from CWD in July, August and September 2013 and 2014. Microbial biomass was greater (p<0.05) in FMM than in PMM, in July, and August 2013 and July 2014, and greater (p<0.05) near CWD than away from CWD in FMM in July and August samplings. Soil microbial CLPP differed between FMM and PMM (p<0.01) according to a principal component analysis and CWD changed microbial CLPP in FMM (p<0.05) but not in PMM. Coarse woody debris increased microbial community functional diversity (average well color development in Biolog Ecoplates) in both cover soils (p<0.05) in August and September 2014. Carbon degrading soil enzyme activities were greater in FMM than in PMM (p<0.05) regardless of distance from CWD but were not affected by CWD. Greater microbial biomass and enzyme activities in FMM than in PMM will increase organic matter decomposition and nutrient cycling, improving plant growth. Enhanced microbial community functional diversity by CWD application in upland reclamation has implications for accelerating upland reclamation after oil sands mining. PMID:26618605

  10. 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.

  11. 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.

  12. 77 FR 19925 - Upland Cotton Base Quality

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-03

    ... starting with the 2012 crop. DATES: Effective date: April 3, 2012. FOR FURTHER INFORMATION CONTACT: Gene... INFORMATION: Background The Farm Service Agency (FSA) operates an upland cotton MAL program for upland cotton... Secretary of Agriculture effective July 24, 1971 (36 FR 13804) relating to notices of proposed...

  13. 27 CFR 9.228 - Indiana Uplands.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... determine the boundary of the Indiana Uplands viticultural area are titled: (1) Tell City, Indiana—Kentucky... Indiana Uplands viticultural area is described as follows: (1) The beginning point is on the Tell City map... Indiana shoreline of the Ohio River, crossing back and forth between the Tell City and Jasper...

  14. 27 CFR 9.228 - Indiana Uplands.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... determine the boundary of the Indiana Uplands viticultural area are titled: (1) Tell City, Indiana—Kentucky... Indiana Uplands viticultural area is described as follows: (1) The beginning point is on the Tell City map... Indiana shoreline of the Ohio River, crossing back and forth between the Tell City and Jasper...

  15. Sewage sludge sugarcane trash based compost and synthetic aggregates as peat substitutes in containerized media for crop production.

    PubMed

    Jayasinghe, G Y; Tokashiki, Yoshihiro; Arachchi, I D Liyana; Arakaki, Mika

    2010-02-15

    Effect of partial substitution of peat in growth media by sewage sludge sugarcane trash based compost (SSC) and synthetic aggregates (SA) on the physical and chemical characteristics of the growth media and on the growth and nutrition of lettuce (Lactuca sativa L.) grown in the substituted media was investigated under this study. SSC was produced from sugarcane trash and sewage sludge. Unconventional SA were produced by low productive acidic red soil with paper waste and starch waste. The treatments assayed were: SSC (40%)+Peat (60%), SA (40%)+Peat (60%), SSC (60%)+SA (40%), SSC (40%)+SA (20%)+Peat (40%) and SSC (40%)+SA (40%)+Peat (20%). Peat only was used as the control. The physical and chemical properties of all growing media were analyzed. SSC-SA based substrates showed adequate physical and chemical properties compared to peat for their use as growing media in horticulture. In relation to the plant growth in peat control, plants grown in the SSC-SA based substrates reached better growth and nutrition. The concentration of trace elements in plant tissues was far lower than the ranges considered phytotoxic for plants. Utilization of SSC and SA can be considered as an alternative media component to substitute the widely using expensive peat in horticulture. PMID:19828249

  16. 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.

  17. Soil Core Sample #2

    USGS Multimedia Gallery

    Soil core obtained from existing goose grazing lawn along the Smith River in the Teshekpuk Lake Special Area of the National Petroleum Reserve - Alaska.  Buried peat layer broken open.  Closer examination of the buried peat layer demonstrates that non-salt-tolerant vegetation from the past...

  18. SALT MARSH VEGETATION RESPONSE TO EDAPHIC AND TOPOGRAPHIC CHANGES FROM UPLAND SEDIMENTATION IN A PACIFIC ESTUARY

    E-print Network

    Kelly, Maggi

    SALT MARSH VEGETATION RESPONSE TO EDAPHIC AND TOPOGRAPHIC CHANGES FROM UPLAND SEDIMENTATION marsh soil properties and topography on sediment fans related to shifts in salt marsh plant community in a distinct edaphic environment, and its expansion into the salt marsh was restricted by elevation in tidal

  19. 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.

  20. 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…

  1. Content of lipids in finnish peat mires

    SciTech Connect

    Fagernaes, L.; Ekman, R.

    1985-01-01

    Peat is a potential raw material for chemical products. Peat extracts, bitumens, obtained from peat with neutral organic solvents, and, in particular, their wax fractions have been of interest with regard to their substituting for other natural waxes. Yields and characteristics of peat extracts have been studied by numerous researchers and acid and saponification values, molecular weights and elements analyses have been determined since the 1930s. New analytical methods have recently been introduced and made it possible to determine the amount and detailed composition of the lipid components of peat extracts by capillary gas chromatography (GC) and mass spectrometry. The aim of this study was to determine the yield and lipid composition of extracts from peat samples collected from different mires in Finland.

  2. 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, most likely from char residues. The isotopic signature of ?13C seems to be slightly affected by smouldering, although the information about vegetational changes are preserved, whereas the ?15N shows a trend positively correlated with the relative N enrichment observed in smouldered peat samples, as also supported by 15N NMR. Compared to flaming fires, smouldering fires produce much lower concentrations of PAH. Furthermore, PAH detected in peat following smouldering fires consist mainly of those with lower molecular weights (i.e., naphthalene, acenaphthene and fluorene). Finally, although concentrations of As, Hg, and Pb increase compared to the FP, their enrichment, relative to Ti, decreases. Such a trend regards mainly the surface layers. These data that suggest smouldering fires may be an important cause of variations observed in peat cores.

  3. 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 solidity of the residual low-powered peat layer does not facilitate formation of wind stable plats. Besides, due to the fact that this territory was formed at the place of former ancient lake, there is a possibility that this territory will be flooded during water full periods for long periods because columbine from the nearby territories and this will lead to the death of forest plants. It is more profitable to use these areas for re-wetting or for creation of water basins.

  4. 7 CFR 1205.305 - Upland cotton.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Upland cotton. 1205.305 Section 1205.305 Agriculture...MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions...

  5. 7 CFR 1205.305 - Upland cotton.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Upland cotton. 1205.305 Section 1205.305 Agriculture...MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions...

  6. 7 CFR 1205.305 - Upland cotton.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Upland cotton. 1205.305 Section 1205.305 Agriculture...MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions...

  7. 7 CFR 1205.305 - Upland cotton.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Upland cotton. 1205.305 Section 1205.305 Agriculture...MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions...

  8. 7 CFR 1205.305 - Upland cotton.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Upland cotton. 1205.305 Section 1205.305 Agriculture...MISCELLANEOUS COMMODITIES), DEPARTMENT OF AGRICULTURE COTTON RESEARCH AND PROMOTION Cotton Research and Promotion Order Definitions...

  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. Microelements in Lowland Peat of the Northeastern Part of the Altai Mountains

    NASA Astrophysics Data System (ADS)

    Shurova, M. V.; Larina, G. V.; Kozlova, S. A.; Shagaeva, L. L.

    2010-05-01

    The greatest areas of bogs are concentrated in the northeastern part of Altai Republic. This place due to a great amount of precipitation and a powerful accumulation of snow with a little drain in comparison with other areas has plenty of bogs. A quarter of all bogs of the Altai Mountains is concentrated here. The bogs develop mainly in the valleys of the rivers. The bogs have a modern origin and the process of bog formation goes at the present time by overgrowing of oxbow and valley lakes, and also by bogging of dry lands - woods and meadows. The area of bogs in relation to the general territory of highlands makes up 1%. Nevertheless, these territories are regarded as complex ecosystems which have economic and scientific value. Let's consider the content of heavy metals in different horizons of the peat under study. The samples of peat of the deposit being examined are characterized by a low total content of zinc: 6,21-44,12 mg/kg. The average amount of zinc in the soils of the Altai Mountains is much larger and makes up 70,3 mg/kg. Quite a significant amount of copper is washed away from peat thickness, its total amount is at the level of 1,58-10,73 mg/kg. The reason for it, probably, lies in the fact that there is a significant amount of fulvic acids in the composition of humic acids which enable the migration of copper beyond the limits of the peat ground in the conditions of the sour environment. A completely different situation is observed in the soils of the Altai mountain area. The biogeochemistry of copper in the soils of the Altai Mountains is thoroughly investigated by M.A.Malgin, A.V.Puzanov, O.A.Yelchininova. Its average amount in the soils of the Altai Mountains makes up 40,6 mg/kg which is twice as much as the abundance ratio in comparison with the world soils. The authors explain this fact as follows: copper is an inactive element in the soils since its ions are easily precipitated by sulfide-, carbonate-, and hydroxide ions, and also are taken up by humic acids of soils. Therefore, notwithstanding the washing type of a water mode, the leaching of copper from the soils of the Altai Mountains is not observed. The amount of cadmium in the investigated lowland peat makes up from 0,12 up to 0,57 mg/kg which is almost two times less than the roughly allowable concentration. Also the monotonous increase of the concentration factor of cadmium upwards on the structure is observed. The peat of the surveyed deposit as far as the amount of cadmium is concerned is actually at the level of the background soils of the Altai mountain area. The amount of lead in the peat under study is not subject to significant fluctuation - from 1,34 up to 10,0 mg/kg which is lower than the average amount characteristic of the soils of the Altai Mountains. The roughly allowable concentration of lead for sour soils makes up 65 mg/kg, therefore the peat under study is non-polluting or lead-free. There is an even distribution of lead in the structure of the axial section. In the distribution of zinc, copper, cadmium, lead in peat thickness there is a contrast between the top layers and the bottom ones. The top layers are characterized by higher concentration of elements. The lowland peat of the northeastern part of Altai Republic in comparison with the West-Siberian peat is characterized by the increased values of zinc and has the same amount of copper and lead.

  11. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

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

  13. 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.

  14. 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.

  15. 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 mineralization driven by increased microbial biomass. Increases in vascular plant abundance and root biomass may therefore increase overall rates of carbon mineralization and peat decomposition within peatland systems and influence the nature of the peatland carbon store.

  16. South Florida wetlands ecosystem; biogeochemical processes in peat

    USGS Publications Warehouse

    Orem, William; U.S. Geological Survey

    1996-01-01

    The South Florida wetlands ecosystem is an environment of great size and ecological diversity (figs. 1 and 2). The landscape diversity and subtropical setting of this ecosystem provide a habitat for an abundance of plants and wildlife, some of which are unique to South Florida. South Florida wetlands are currently in crisis, however, due to the combined effects of agriculture, urbanization, and nearly 100 years of water management. Serious problems facing this ecosystem include (1) phosphorus contamination producing nutrient enrichment, which is causing changes in the native vegetation, (2) methylmercury contamination of fish and other wildlife, which poses a potential threat to human health, (3) changes in the natural flow of water in the region, resulting in more frequent drying of wetlands, loss of organic soils, and a reduction in freshwater flow to Florida Bay, (4) hypersalinity, massive algal blooms, and seagrass loss in parts of Florida Bay, and (5) a decrease in wildlife populations, especially those of wading birds. This U.S. Geological Survey (USGS) project focuses on the role of organic-rich sediments (peat) of South Florida wetlands in regulating the concentrations and impact of important chemical species in the environment. The cycling of carbon, nitrogen, phosphorus, and sulfur in peat is an important factor in the regulation of water quality in the South Florida wetlands ecosystem. These elements are central to many of the contamination issues facing South Florida wetlands, such as nutrient enrichment, mercury toxicity, and loss of peat. Many important chemical and biological reactions occur in peat and control the fate of chemical species in wetlands. Wetland scientists often refer to these reactions as biogeochemical processes, because they are chemical reactions usually mediated by microorganisms in a geological environment. An understanding of the biogeochemical processes in peat of South Florida wetlands will provide a basis for evaluating the effects on water quality of (1) constructing buffer wetlands to alleviate nutrient contamination and (2) replumbing the ecosystem to restore natural water flow. The results may also suggest new approaches for solving problems of contamination and water quality in these wetlands. A second focus of this project will be on the geochemical history of the South Florida ecosystem. Peat is a repository of the history of past environmental conditions in the wetland. Before effective action can be taken to correct many of the problems facing these wetlands, we must first study the biogeochemistry of the peat at depth in order to understand whether current problems are the result of recent human activity or are part of a long-term natural cycle. Coordination with other (USGS) projects for South Florida is ongoing. These projects are studying the biological history of the ecosystem by using pollen and shells buried in the peat, together with procedures for dating the peat at various depths, to develop an overall ecosystem history model, with emphasis on the last 100 years.

  17. 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 ?mol 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 ?atm 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.

  18. 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 ?mol 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 ?atm 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.

  19. Monitoring the effects of manure policy in the Peat region, Netherlands

    NASA Astrophysics Data System (ADS)

    Hooijboer, Arno; Buis, Eke; Fraters, Dico; Boumans, Leo; Lukacs, Saskia; Vrijhoef, Astrid

    2014-05-01

    Total N concentrations in farm ditches in the Peat region of the Netherlands are on the average twice as high as the Good Ecological Potential value of the Water Framework Directive. Since ditches are connected to regional surface water, they may contribute to eutrophication. The minerals policy aims to improve the water quality. In the Netherlands, the effectiveness of the minerals policy on water quality is evaluated with data from the National Minerals Policy Monitoring Programme (LMM). This regards farm data on the quality of water leaching from the root zone and on farm practices. The soil balance nitrogen surpluses decreased between 1996 and 2003 on dairy farms in the Peat region. However, no effect on root zone leaching was found. This study aims to show how monitoring in the Peat region can be improved in order to link water quality to agricultural practice. Contrary to the other Dutch regions, nitrate concentrations in root zone leaching on farms in the Peat region are often very low (90% of the farms below 25 mg/l) due to the reduction of nitrate (denitrification). The main nitrogen (N) components in the peat region waters are ammonium and organic N. Total N is therefore a better measure for N concentrations in the Peat region. The ammonium concentration in groundwater in Dutch peat soils increases with depth. It is assumed that the deeper ammonia-rich water is older and relates to anaerobic peat decomposition instead of agricultural practice. Recent infiltrated low-ammonium water, lies like a thin freshwater lens on the older water. In the Peat region, root zone leaching is monitored by taking samples from the upper meter of groundwater. Unintended, often both lens water and older water are sampled and this distorts the relation between agricultural practice and water quality. In the Peat region, the N surplus is transported with the precipitation surplus to ditches. The relation between the N surplus and the total N in ditch water is therefore better than between N surplus and total N in root zone leaching. The precipitation surplus flows to ditches directly or via open field drains. However, the ditches may be fed partly with older water (seepage of groundwater). In the open field drain only recent water will occur. We expect that monitoring the water quality of the open field drains may even better reflect changes in agricultural practices. These data may also improve the understanding of contribution of agricultural nitrogen and natural nitrogen, necessary to develop measures to decrease the total-N concentration in ditch water.

  20. CO2 Efflux from Cleared Mangrove Peat Catherine E. Lovelock1

    E-print Network

    Ruess, Roger W.

    CO2 Efflux from Cleared Mangrove Peat Catherine E. Lovelock1 *, Roger W. Ruess2 , Ilka C. Feller3 1: 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

  1. Feedback control of the rate of peat formation Lisa R. Belyea1*

    E-print Network

    , UK The role of peatlands in the global carbon cycle is confounded by two inconsistencies. First and carbon sequestration. Keywords: peatlands; soil organic matter; ecosystem dynamics; carbon cycle 1 in the role of peatlands in the global carbon cycle is the predictability of the processes. Peat has accumu

  2. 2008 Macmillan Publishers Limited. All rights reserved. 2008 Macmillan Publishers Limited. All rights reserved. High sensitivity of peat decomposition

    E-print Network

    Moorcroft, Paul R.

    in a changing climate. In our long-term simulation, an experimental warming of 4 C causes a 40% loss of soil rights reserved. LETTERS High sensitivity of peat decomposition to climate change through water paludification using analytical models that include feedback between soil depth change and hydrology3,6,7 , fast

  3. Mercury methylation in forested uplands; how important is it?

    NASA Astrophysics Data System (ADS)

    Shanley, J. B.; Marvin-Dipasquale, M.; Schuster, P. F.; Chalmers, A.; Reddy, M. M.

    2004-05-01

    Episodic fluxes of mercury during high flows at the headwater catchment at the Sleepers River Research Watershed in Vermont indicate that uplands are an important source of total mercury (Hg) to known downstream methylation sites (i.e. large wetlands). Methylmercury (MeHg) behavior in streamwater, soil water, and sediment porewater coupled with high potential methylation rates suggests that forested uplands may be significant source areas for MeHg as well. In a July 2003 incubation, potential Hg methylation rates exceeded potential demethylation rates by factors of 1.6 each in shallow (0-4 cm) swamp and riparian soils and by 19.6 in anoxic stream sediments. The stream sediment had the greatest methylation rate of 7.5 ng/ g of wet sediment / day. However, MeHg concentrations in filtered (0.4 um) porewater at these sites ranged only from 0.07 to 0.37 ng/ L, similar to the range at low-lying wetland sites elsewhere in Vermont (0.06 to 0.56 ng/L). In Sleepers River headwaters as well as larger Vermont rivers, most of the MeHg export occurs during snowmelt and summer / fall storms, with nearly all of the MeHg occurring in the particulate phase. Stream total Hg and MeHg concentrations were consistently correlated, suggesting a common source, probably soil organic matter. The methylation efficiency (ratio MeHg / total Hg) was near 2% in the Sleepers River headwaters, similar to that in Vermont rivers draining large wetland systems, indicating that the methylation process originates in the headwaters.

  4. The Soils of Bowie, Denton, Freestone, and Red River Counties. 

    E-print Network

    Fraps, G. S. (George Stronach)

    1928-01-01

    in Denton County. The subsoils are likewise low in plant food and they are more acid than the surface soils. The upland prairie soils are better supplied with plant food and with lime than the forested soils. They contain two or three times as much... of analyses of soils averaged by groups. - upland (Forested) Surface Soil Bowie County. .................................. Denton County (Cross Timbers). .................. Freestone County. ............................... Red River County...

  5. The recovery of the recurrent parent in upland cotton 

    E-print Network

    Rosenbaum, Ross Corbet

    2003-01-01

    Breeders have made numerous improvements in upland cotton (Gossypium hirsutum L.) over the past century. The future improvement of yield and quality in upland cotton may rely on greater use of exotic accessions to expand the genetic diversity...

  6. Measurement and modeling of soil-water dynamics and evapotranspiration of drained peatland soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Natural peat soils serve as important sinks for nutrients, organic components, and water. Peat soils can pose major environmental problems when they are drained for agricultural production, which may change their role in the landscape from a sink to a source. To successfully restore and conserve pea...

  7. 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.

  8. 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.

  9. 7 CFR 1427.103 - Upland cotton Domestic User Agreement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Upland cotton Domestic User Agreement. 1427.103... CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.103 Upland cotton Domestic User Agreement. (a) Payments...

  10. 7 CFR 1427.103 - Upland cotton Domestic User Agreement.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Upland cotton Domestic User Agreement. 1427.103... CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.103 Upland cotton Domestic User Agreement. (a) Payments...

  11. 7 CFR 1427.103 - Upland cotton Domestic User Agreement.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Upland cotton Domestic User Agreement. 1427.103... CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.103 Upland cotton Domestic User Agreement. (a) Payments...

  12. 7 CFR 1427.103 - Upland cotton Domestic User Agreement.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Upland cotton Domestic User Agreement. 1427.103... CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.103 Upland cotton Domestic User Agreement. (a) Payments...

  13. 7 CFR 1427.101 - Eligible upland cotton.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Eligible upland cotton. 1427.101 Section 1427.101... OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.101 Eligible upland cotton. (a) For purposes of this subpart, eligible...

  14. 7 CFR 1427.101 - Eligible upland cotton.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Eligible upland cotton. 1427.101 Section 1427.101... OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.101 Eligible upland cotton. (a) For purposes of this subpart, eligible...

  15. 7 CFR 1427.101 - Eligible upland cotton.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Eligible upland cotton. 1427.101 Section 1427.101... OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.101 Eligible upland cotton. (a) For purposes of this subpart, eligible...

  16. 7 CFR 1427.101 - Eligible upland cotton.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Eligible upland cotton. 1427.101 Section 1427.101... OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.101 Eligible upland cotton. (a) For purposes of this subpart, eligible...

  17. 7 CFR 1427.101 - Eligible upland cotton.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Eligible upland cotton. 1427.101 Section 1427.101... OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.101 Eligible upland cotton. (a) For purposes of this subpart, eligible...

  18. 7 CFR 1427.103 - Upland cotton Domestic User Agreement.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Upland cotton Domestic User Agreement. 1427.103... CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COTTON Economic Adjustment Assistance to Users of Upland Cotton § 1427.103 Upland cotton Domestic User Agreement. (a) Payments...

  19. Minerals yearbook, 1993: Peat. Annual report

    SciTech Connect

    Bolen, W.P.

    1994-11-01

    The U.S. Bureau of Mines (USBM) annual survey of domestic peat producers in the 48 contiguous United States reflected a 3% increase in production accompanied by the closure of two U.S. peat operations in the States of Maine and Michigan and the first full year of operations at a new Minnesota peat mine. Sales volume fell 6% to just more than 0.6 million tons, although the total value of producer sales increased slightly to $16.8 million, f.o.b. plant. Idled and discontinued operations continued to liquidate stocks.

  20. 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.

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

    PubMed Central

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

    1999-01-01

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

  2. 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.

  3. Genetic variation for yield and fiber quality response to supplemental irrigation within the Pee Dee Upland cotton germplasm collection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water availability is a major factor influencing the development of upland cotton (Gossypium hirsutum L.) cultivars and sustainable cotton production in the southeast USA because of endemic, intermittent drought events occurring in the region resulting from shallow, coarse textured soils and irregul...

  4. History and Vulnerability of Permafrost in Upland and Lowland Boreal Landscapes (Invited)

    NASA Astrophysics Data System (ADS)

    Jorgenson, M. T.; Kanevskiy, M. Z.; Shur, Y.; Harden, J. W.; O'Donnell, J.; Wickland, K. P.; Ewing, S. A.; Striegl, R. G.; Zhuang, Q.

    2010-12-01

    The history of permafrost aggradation and degradation in boreal landscapes can be interpreted through surface geomorphology, ground-ice characteristics, geochemistry, and ecological indicators. This history, which varies greatly in relation to topography, surficial materials, and ecological succession, can be simplified into four basic patterns involving rocky uplands, loamy uplands, gravelly-sandy lowlands, and peaty-loamy lowlands. In rocky uplands, permafrost conditions reflect fluctuations only over decades to century-long periods due to low latent heat of ice-poor soils and frequent fires, and history is poorly preserved. In loamy uplands with loess, water-shedding slopes, surface thermal properties, ecological recovery, and high latent heat in underlying massive ice make permafrost highly resilient. Consequently, permafrost history is well preserved as cryostructures, isotopic signatures, and buried soils. Permafrost can persist over tens to perhaps hundreds of thousands of years. In gravelly-sandy lowlands with fluvial gravels and eolian sand sheets, permafrost presence fluctuates over century periods, but because permafrost can affect surface and groundwater, changing water levels leave a legacy of plant macrofossils from aquatic and terrestrial ecosystems that can be used interpreting permafrost history. In peaty-loamy lowlands with lowland loess and abandoned floodplain deposits, water-impounding topography and permafrost-inducing soil thermal properties are conducive to permafrost fluctuations over decadal, century, and millennial periods that leave a rich legacy of plant materials indicative of specific conditions of permafrost formation and degradation. These varying responses of permafrost to environmental changes complicate the assessment of the role of permafrost in the sequestration and release of soil carbon into the atmosphere and surface waters.

  5. Peat accumulation in drained thermokarst lake basins in continuous, ice-rich permafrost, northern Seward Peninsula, Alaska

    USGS Publications Warehouse

    Jones, Miriam C.; Grosse, Guido; Jones, Benjamin M.; Anthony, Katey Walter

    2012-01-01

    Thermokarst lakes and peat-accumulating drained lake basins cover a substantial portion of Arctic lowland landscapes, yet the role of thermokarst lake drainage and ensuing peat formation in landscape-scale carbon (C) budgets remains understudied. Here we use measurements of terrestrial peat thickness, bulk density, organic matter content, and basal radiocarbon age from permafrost cores, soil pits, and exposures in vegetated, drained lake basins to characterize regional lake drainage chronology, C accumulation rates, and the role of thermokarst-lake cycling in carbon dynamics throughout the Holocene on the northern Seward Peninsula, Alaska. Most detectable lake drainage events occurred within the last 4,000 years with the highest drainage frequency during the medieval climate anomaly. Peat accumulation rates were highest in young (50–500 years) drained lake basins (35.2 g C m?2 yr?1) and decreased exponentially with time since drainage to 9 g C m?2 yr?1 in the oldest basins. Spatial analyses of terrestrial peat depth, basal peat radiocarbon ages, basin geomorphology, and satellite-derived land surface properties (Normalized Difference Vegetation Index (NDVI); Minimum Noise Fraction (MNF)) from Landsat satellite data revealed significant relationships between peat thickness and mean basin NDVI or MNF. By upscaling observed relationships, we infer that drained thermokarst lake basins, covering 391 km2 (76%) of the 515 km2 study region, store 6.4–6.6 Tg organic C in drained lake basin terrestrial peat. Peat accumulation in drained lake basins likely serves to offset greenhouse gas release from thermokarst-impacted landscapes and should be incorporated in landscape-scale C budgets.

  6. Mass tree mortality leads to mangrove peat collapse at Bay Islands, Honduras after Hurricane Mitch

    USGS Publications Warehouse

    Cahoon, D.R.; Hensel, P.; Rybczyk, J.; McKee, K.L.; Proffitt, C.E.; Perez, B.C.

    2003-01-01

    We measured sediment elevation and accretion dynamics in mangrove forests on the islands of Guanaja and Roatan, Honduras, impacted by Hurricane Mitch in 1998 to determine if collapse of underlying peat was occurring as a result of mass tree mortality. Little is known about the balance between production and decomposition of soil organic matter in the maintenance of sediment elevation of mangrove forests with biogenic soils. Sediment elevation change measured with the rod surface elevation table from 18 months to 33 months after the storm differed significantly among low, medium and high wind impact sites. Mangrove forests suffering minimal to partial mortality gained elevation at a rate (5 mm yeara??1) greater than vertical accretion (2 mm yeara??1) measured from artificial soil marker horizons, suggesting that root production contributed to sediment elevation. Basin forests that suffered mass tree mortality experienced peat collapse of about 11 mm yeara??1 as a result of decomposition of dead root material and sediment compaction. Low soil shear strength and lack of root growth accompanied elevation decreases. Model simulations using the Relative Elevation Model indicate that peat collapse in the high impact basin mangrove forest would be 37 mm yeara??1 for the 2 years immediately after the storm, as root material decomposed. In the absence of renewed root growth, the model predicts that peat collapse will continue for at least 8 more years at a rate (7 mm yeara??1) similar to that measured (11 mm yeara??1). Mass tree mortality caused rapid elevation loss. Few trees survived and recovery of the high impact forest will thus depend primarily on seedling recruitment. Because seedling establishment is controlled in large part by sediment elevation in relation to tide height, continued peat collapse could further impair recovery rates.

  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. A Few Issues on the Peat Research in the Altai Mountains

    NASA Astrophysics Data System (ADS)

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

    2010-05-01

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

  9. Radioactivity of peat mud used in therapy.

    PubMed

    Karpi?ska, Maria; Mnich, Krystian; Kapa?a, Jacek; Bielawska, Agnieszka; Kulesza, Grzegorz; Mnich, Stanis?aw

    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

  10. Experiments and Observation of Peat Smouldering Fires 

    E-print Network

    Ashton, Clare; Rein, Guillermo; Dios, JD; Torero, Jose L; Legg, C; Davies, M; Gray, A

    2007-01-30

    If a subsurface layer of peat is ignited, it smoulders (flameless combustion) slowly but steadily. These fires propagate for long periods of time (days, weeks, even years), are particularly difficult to extinguish and can ...

  11. Catchment-scale deposition and redistribution of Chernobyl radiocaesium in upland Britain

    SciTech Connect

    Higgitt, D.L.; Rowan, J.S. ); Walling, D.E. )

    1993-01-01

    Fallout from the Chernobyl nuclear accident in April 1986 resulted in a significant increase in the inventory of radiocaesium in many areas of upland Britain. Caesium-137 derived from nuclear weapons testing in the 1950s and 1960s has been widely used as a sediment tracer to monitor soil erosion. The presence of Chernobyl fallout provides an opportunity to examine the short-term, post-input behavior of radiocaesium in upland soils and assess its potential for investigating sediment transfer in upland systems. Sampling undertaken in the catchment of Lake Vyrnwy, North Wales considered the vertical distribution of radiocaesium in different soil types, the catchment-wide variation in Chernobyl fallout deposition, and the radiocaesium content of sediment from a variety of slope and fluvial environments. Whilst uncertainty surrounding the estimation of baseline inventories limits the detailed interpretation of short-term sediment dynamics, it is apparent that the sediment-associated redistribution of Chernobyl radioactivity may result in its accumulation in certain parts of the catchment over longer timescales. 18 refs., 6 figs., 2 tabs.

  12. Actinobacterial Nitrate Reducers and Proteobacterial Denitrifiers Are Abundant in N2O-Metabolizing Palsa Peat

    PubMed Central

    Palmer, Katharina

    2012-01-01

    Palsa peats are characterized by elevated, circular frost heaves (peat soil on top of a permanently frozen ice lens) and are strong to moderate sources or even temporary sinks for the greenhouse gas nitrous oxide (N2O). Palsa peats are predicted to react sensitively to global warming. The acidic palsa peat Skalluvaara (approximate pH 4.4) is located in the discontinuous permafrost zone in northwestern Finnish Lapland. In situ N2O fluxes were spatially variable, ranging from 0.01 to ?0.02 ?mol of N2O m?2 h?1. Fertilization with nitrate stimulated in situ N2O emissions and N2O production in anoxic microcosms without apparent delay. N2O was subsequently consumed in microcosms. Maximal reaction velocities (vmax) of nitrate-dependent denitrification approximated 3 and 1 nmol of N2O per h per gram (dry weight [gDW]) in soil from 0 to 20 cm and below 20 cm of depth, respectively. vmax values of nitrite-dependent denitrification were 2- to 5-fold higher than the vmax nitrate-dependent denitrification, and vmax of N2O consumption was 1- to 6-fold higher than that of nitrite-dependent denitrification, highlighting a high N2O consumption potential. Up to 12 species-level operational taxonomic units (OTUs) of narG, nirK and nirS, and nosZ were retrieved. Detected OTUs suggested the presence of diverse uncultured soil denitrifiers and dissimilatory nitrate reducers, hitherto undetected species, as well as Actino-, Alpha-, and Betaproteobacteria. Copy numbers of nirS always outnumbered those of nirK by 2 orders of magnitude. Copy numbers of nirS tended to be higher, while copy numbers of narG and nosZ tended to be lower in 0- to 20-cm soil than in soil below 20 cm. The collective data suggest that (i) the source and sink functions of palsa peat soils for N2O are associated with denitrification, (ii) actinobacterial nitrate reducers and nirS-type and nosZ-harboring proteobacterial denitrifiers are important players, and (iii) acidic soils like palsa peats represent reservoirs of diverse acid-tolerant denitrifiers associated with N2O fluxes. PMID:22660709

  13. Testing the potential of bacterial branched tetraether membrane lipids as temperature proxy in peat and immature coal deposits

    NASA Astrophysics Data System (ADS)

    Weijers, J. W. H.; Steinmann, P.; Hopmans, E. C.; Basiliko, N.; Finkelstein, S. A.; Johnson, K. R.; Schouten, S.; Sinninghe Damsté, J. S.

    2012-04-01

    Branched glycerol dialkyl glycerol tetraether (brGDGT) membrane lipids occur ubiquitously in peat and soil. In soil, the degree of methylation and cyclisation of branched tetraethers (MBT index and CBT ratio, respectively) has shown to relate to both soil pH and annual mean air temperature (MAT). Using this relation, past annual MATs can be reconstructed by analysing brGDGTs in marine sediment records near large river outflows. More recently, the potential of this MBT/CBT proxy is also being explored in lakes. Despite being more abundant in peat than soils, however, the utility of the proxy has not yet been fully explored in peat records. Present day peat records generally extent back to the early Holocene, but if the MBT/CBT proxy were shown to be applicable in peat deposits, there is also potential to apply it to immature coal deposits like lignites, which could provide valuable snapshots of continental climate back to the early Cenozoic. Here results are presented of analyses of different peats in south eastern Canada, showing that the pH of peat along a nutrient gradient is rather well reflected by the CBT. Annual MAT reconstructions based on the MBT/CBT soil calibration, however, tend to overestimate measured MAT. This is also the case for peat analysed from the surface of Etang de la Gruère peat bog in the Swiss Jura Mountains. Along the 6m depth profile of this bog (~13ka), CBT-reconstructed pH is compared with in-situ measured pore water pH showing that the brGDGT composition does not reflect present-day in-situ conditions. Instead, it reflects a stratigraphic boundary between Carex and Sphagnum dominated peat at 4 m depth that is not present in the pore water profile, testifying to a 'fossil' nature of the brGDGTs down the peat bog. Analyses of three immature coals of the Argonne Premium Coal Series reveal that branched GDGTs are present in the most immature coal, the Beulah Zap lignite (Ro = 0.25%), and only just above detection limit in the Wyodak Anderson coal (Ro = 0.32%), both of about the same age (Late Palaeocene). In the more mature Illinois #6 coal (Ro = 0.46%), brGDGTs are completely absent. In the Denver Basin, a comparison is made between outcrop and drilled core samples of Palaeocene lignites. BrGDGTs are preserved in the core samples, although in low quantities compared to peat. Outcrop samples are clearly overprinted by modern soil derived brGDGTs, despite digging a meters deep trench, which shows the need to obtain fresh non-weathered samples by coring. Reconstructed annual MAT for both the Beulah Zap and the Denver Basin lignites are several degrees higher than estimates based on leaf margin and oxygen isotope analyses from the same sites. Both reconstructions do testify, nevertheless, to the warm continental conditions during the early Cenozoic of the central U.S.A.. Although further validation is required, potentially in the form of a specific peat calibration, these results do show potential for application of the MBT/CBT temperature proxy in peat and lignite deposits.

  14. Mobile geophysical study of peat deposits in Fuhrberger Field, Germany

    NASA Astrophysics Data System (ADS)

    Wunderlich, T.; Petersen, H.; Hagrey, S. A. al; Rabbel, W.

    2012-04-01

    In the water protection area of Fuhrberger Field, north of Hanover, geophysical techniques were applied to study the stakeholder problem of the source detection for nitrate accumulations in the ground water. We used our mobile multisensor platform to conduct measurements using Ground Penetrating Radar (GPR, 200 MHz antenna) and Electromagnetic Induction (EMI, EM31). This aims to study the subsurface occurrences of peat deposits (surplus of organic carbon) supposed to be a source of nitrate emissions due to the aeration and the drawdown of groundwater levels (e.g. by pumping, drainage etc.). Resulting EMI and GPR signals show high data quality. Measured apparent electrical conductivity shows very low values (<10 mS/m) due to the mainly sandy subsurface. For this medium, both methods are expected to penetrate down to 3-5 m depth. GPR radargrams, time slices of GPR reflection energy and EMI apparent electrical conductivities are plotted on aerial photographs and compared to each other's and with vegetation intensity. We could separate areas characterized by low reflection energy and high conductivity, and vice versa. Briefly, organic rich sediments such as peats are assumed to have a relative high conductivity and thus low GPR reflectivity. Some areas of local conductivity increase correspond to a deep reflection interface (as seen in the radargrams), which even vanishes due to the high attenuation caused by the high conductivity. This implies that the upper layer is more conductive than the lower layer. Several local areas with these characteristics are found at the study sites. We recommend shallow drillings at representative points to deliver the necessary confirmation with ground truth information. Acknowledgments: iSOIL (Interactions between soil related sciences - Linking geophysics, soil science and digital soil mapping) is a Collaborative Project (Grant Agreement number 211386) co-funded by the Research DG of the European Commission within the RTD activities of the FP7 Thematic Priority Environment.

  15. A comparison between conventional and AMS [sup 14]C dates on basal salt marsh peats from coastal Maine. [Accelerator Mass Spectroscopy

    SciTech Connect

    Gehrels, R.W.; Belknap, D.F. . Dept. of Geological Sciences)

    1992-01-01

    This study reports AMS dates from four Maine salt marshes: Webbannet Marsh (Wells), Morse and Sprague River marshes (Phippsburg), and Sanborn Cove marsh (Machiasport). The AMS dates are compared with conventional dates on bulk samples obtained from either the same cores or from other cores at comparable depths. Four AMS dates from the Webhannet and Sanborn Cove marshes were considerably older than their conventional counterparts, by as much as 1,000 years. Three causes for this age discrepancy are suggested. First, under slow rates of marsh accretion, peats remain within the root zone of modern plants for a relatively long period, causing a continued input of younger carbon. Intruded roots are undetectable in the highly macerated, 4,000--5,000 C-14 year old peats. Another source of contamination is the percolation of mobile humic acids along the impermeable Pleistocene substrate. Finally, a date on a bulk peat of 10 cm vertical extent represents an average age for a portion of peat that spans a time interval possibly of several centuries. The age difference between the bulk date and the AMS date from the base of the peat increases with decreasing rates of marsh accretion. The forested steep slopes of the upland surrounding the marsh seem a likely source of old carbon that can easily be washed onto the marsh surface. The slow rate of late-Holocene sea-level rise in Maine, as well as the geologic and hydrologic setting of the salt marshes, make conventional C-14 dating of salt marsh peats in Maine a problematic affair. This study implies that AMS dates may be needed to verify Holocene sea-level curves from other coastal areas that have hitherto been based solely on conventional C-14 peat dates.

  16. The S-transform: a Tool for Assessing Local Changes in Biogenic Gas Content in Peat from GPR Data?

    NASA Astrophysics Data System (ADS)

    Terry, N.; Zhongjie, Y.; Slater, L. D.

    2013-12-01

    Time-domain analysis of ground penetrating radar (GPR) data has been used to infer variation in biogenic gas content in peat soils. We examine the potential of frequency-domain methods for further assessing biogenic gas variation from GPR data. In particular, the S-transform is an algorithm to assess time-dependent frequency content. Each returned GPR trace is a time-series, therefore it is straightforward to compute frequency content of a returned radar trace to see how frequency content varies along that trace. The physical properties of soils will affect the frequency content of returned ground penetrating radar signals. Specifically, we postulate that development of gas bubbles in peat will cause preferential attenuation of the high frequency portion of the returned signal as a result of signal scattering. Laboratory results from a time-lapse GPR transmission study are presented. In this study, 1200 MHz antennas were used to sample a ~0.25 m by 0.25 m peat block taken from Caribou Bog, Maine for eight weeks on a twice daily basis. Data were collected across an upper, middle and lower section of the peat at three horizontal positions. Meanwhile, a dynamic chamber system was used to monitor methane flux from the peat surface. The frequency content of GPR data shows a clear correspondence with the dynamic chamber gas flux measurements. In particular, total methane flux shows an increasing trend for the duration of the experiment; these changes coincide with increases in low-frequency (500-1000 MHz) S-transform amplitudes primarily focused within a particular region of the peat block. These results suggest that the S-transform is a useful tool for monitoring changes in biogenic gas content in peat soils where time-lapse GPR data are available.

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

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

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

  18. 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.

  19. 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.

  20. Effects of upland disturbance and instream restoration on hydrodynamics and ammonium uptake in headwater streams

    SciTech Connect

    Roberts, Brian J; Mulholland, Patrick J; Houser, Jeffrey N

    2007-01-01

    Delivery of water, sediments, nutrients, and organic matter to stream ecosystems is strongly influenced by the catchment of the stream and can be altered greatly by upland soil and vegetation disturbance. At the Fort Benning Military Installation (near Columbus, Georgia), spatial variability in intensity of military training results in a wide range of intensities of upland disturbance in stream catchments. A set of 8 streams in catchments spanning this upland disturbance gradient was selected for investigation of the impact of disturbance intensity on hydrodynamics and nutrient uptake. The size of transient storage zones and rates of NH4+ uptake in all study streams were among the lowest reported in the literature. Upland disturbance did not appear to influence stream hydrodynamics strongly, but it caused significant decreases in instream nutrient uptake. In October 2003, coarse woody debris (CWD) was added to of the study streams (spanning the disturbance gradient) in an attempt to increase hydrodynamic and structural complexity with the goals of enhancing biotic habitat and increasing nutrient uptake rates. CWD additions had positive short-term (within 1 mo) effects on hydrodynamic complexity (water velocity decreased and transient storage zone cross-sectional area, relative size of the transient storage zone, fraction of the median travel time attributable to transient storage over a standardized length of 200 m, and the hydraulic retention factor increased) and nutrient uptake (NH4+ uptake rates increased). Our results suggest that water quality in streams with intense upland disturbances can be improved by enhancing instream biotic nutrient uptake capacity through measures such as restoring stream CWD.

  1. Effects of upland disturbance and instream restoration on hydrodynamics and ammonium uptake in headwater streams

    USGS Publications Warehouse

    Roberts, B.J.; Mulholland, P.J.; Houser, J.N.

    2007-01-01

    Delivery of water, sediments, nutrients, and organic matter to stream ecosystems is strongly influenced by the catchment of the stream and can be altered greatly by upland soil and vegetation disturbance. At the Fort Benning Military Installation (near Columbus, Georgia), spatial variability in intensity of military training results in a wide range of intensities of upland disturbance in stream catchments. A set of 8 streams in catchments spanning this upland disturbance gradient was selected for investigation of the impact of disturbance intensity on hydrodynamics and nutrient uptake. The size of transient storage zones and rates of NH4+ uptake in all study streams were among the lowest reported in the literature. Upland disturbance did not appear to influence stream hydrodynamics strongly, but it caused significant decreases in instream nutrient uptake. In October 2003, coarse woody debris (CWD) was added to 1/2 of the study streams (spanning the disturbance gradient) in an attempt to increase hydrodynamic and structural complexity, with the goals of enhancing biotic habitat and increasing nutrient uptake rates. CWD additions had positive short-term (within 1 mo) effects on hydrodynamic complexity (water velocity decreased and transient storage zone cross-sectional area, relative size of the transient storage zone, fraction of the median travel time attributable to transient storage over a standardized length of 200 m, and the hydraulic retention factor increased) and nutrient uptake (NH4+ uptake rates increased). Our results suggest that water quality in streams with intense upland disturbances can be improved by enhancing instream biotic nutrient uptake capacity through measures such as restoring stream CWD. ?? 2007 by The North American Benthological Society.

  2. QTLs associated with root traits increase yield in upland rice when transferred through marker-assisted selection.

    PubMed

    Steele, K A; Price, A H; Witcombe, J R; Shrestha, Roshi; Singh, B N; Gibbons, J M; Virk, D S

    2013-01-01

    Altering root morphology of rice (Oryza sativa L.) cultivars could improve yields in drought-prone upland ecosystems. Marker-assisted backcross breeding was used to introgress four QTLs for root traits into an upland rice cultivar. The QTLs had previously been identified under experimental conditions in a different genetic background. The introgressed lines and the recurrent parent were grown for 6 years by resource-poor farmers in upland sites in Eastern India and yields recorded. In combination the QTLs significantly increased yield by 1 t ha(-1) under relatively favourable field conditions. In less favourable trials, the QTL effects were not detected due to greater heterogeneity in soil-water availability in very low yielding environments and consequent yield variability. Root studies under controlled conditions showed that lines with the introgressions had longer roots throughout tillering than the recurrent parent (14 cm longer 2 weeks after sowing). Therefore, both improved roots and increased yield can be attributed to the introgression of QTLs. This is the first demonstration that marker-assisted backcross breeding (MABC) to introgress multiple root QTLs identified under controlled conditions is an effective strategy to improve farmers' yields of upland rice. The strategy was used to breed a novel upland rice cultivar that has been released in India as Birsa Vikas Dhan 111. PMID:22968512

  3. Heterotrophic respiration in drained tropical peat temperatures influenced by shading gradient

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

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

  4. Understanding the spatial structure of peat permeability around natural pipes in blanket peatlands

    NASA Astrophysics Data System (ADS)

    Cunliffe, Andrew; Baird, Andy; Holden, Joseph

    2014-05-01

    Understanding the spatial structure of peat permeability around natural pipes in blanket peatlands We present the results of a detailed investigation of fine-scale variations in the permeability or hydraulic conductivity (K) of the peat around a natural pipe in a blanket peatland. Both vertical K and horizontal K ranged over seven orders of magnitude over scales of decimetres. K was found to be more variable than indicated by previous research. This finding has important implications for the approaches currently employed to investigate peatland hydrological processes, and the parameterisation of models used to simulate these complex ecohydrological systems. We also observed considerable spatial structuring in K. Lateral K parallel to the pipe was significantly greater than lateral K perpendicular to the pipe. Critically, a wedge of poorly-humified, high-permeability peat was present directly above the pipe, forming a hydrological connection between the peatland surface and the perennially-flowing pipe. These observations advance our mechanistic understanding of pipeflow generation in peatlands. We also attempted to investigate K across the pipe-peat interface to test for a hypothesised low-K skin; however, this was precluded by sample length dependency, which suggests that it is inappropriate to compare K measurements between peat samples of different lengths. Overall, we argue that high resolution work such as this is required for the development of more accurate perceptual models of peatland hydrological systems. Cunliffe, A. M., A. J. Baird, and J. Holden (2013), Hydrological hotspots in blanket peatlands: Spatial variation in peat permeability around a natural soil pipe, Water Resources Research, Vol.49, doi:10.1002/wrcr.20435.

  5. Comparison on the performance of five different electromagnetic sensors in sphagnum peat

    NASA Astrophysics Data System (ADS)

    Daniela, Reineke; Weber, Tobias K. D.; Durner, Wolfgang

    2014-05-01

    Electromagnetic (EM) soil moisture sensors are widely used to measure water contents in porous media, particularly in field studies. The accurate determination of saturation states in soils is vital for many environmentally related research questions. Electromagnetic water content measurements are based on the determination of the dielectric permittivity of a medium. As the dielectric permittivity is high in water compared to other soil constituents it can be related to soil water content. However, this method is affected by the properties of the medium investigated and until now there is little knowledge about its applicability to peat soils. The aim of our study was to investigate the performance of electromagnetic sensors to measure water content in sphagnum peat and to identify problems of the EM method associated with this special substrate. For this purpose, a comparison under laboratory conditions was conducted. Five different commercially available types of soil moisture sensor were selected with a range of geometries and various measurement principles. These included a time domain reflectometry probe, IMKO Trime Pico 64, and four frequency domain technique devices, namely the Stevens Hydra Probe, Delta-T Wet-2, Decagon 5TM and Decagon GS3. For this a sphagnum sample (40 cm by 60 cm by 30 cm), taken from a soli-ombrotrophic peat bog, was instrumented with the five sensor types at two different depths. Water content was altered by continuous evaporation at the top. To check the water content readings for plausibility, matrix potentials in four depths and the weight of the sample were monitored during the evaporation experiment. The dielectric permittivity readings from the soil moisture sensors were converted to volumetric water content either by calibration equations for organic substrates supplied by the manufacturer or from calibration equations for sphagnum found in scientific publications. In both parameters, dielectric permittivity and volumetric water content, large systematic differences between the sensor types were observed, especially in the wet range. With four sensor types giving plausible results in both measurement depths, one sensor type gave unplausible readings during most of the experiment. While the earlier suggests that a sphagnum- and possibly peat type specific calibration equation for each sensor might be necessary, the latter indicates that some sensor geometries could be inappropriate for peat soils.

  6. Soil Property Effects on Wind Erosion of Organic Soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Histosols (also known as organic soils, mucks, or peats) are soils that are dominated by organic matter (>20%) in half or more of the upper 80 cm. Forty four states have a total of 21 million ha of histosols in the United States. These soils, when intensively cropped, are subject to wind erosion r...

  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. 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.

  9. Carbon Emissions from Smouldering Peat in Shallow and Strong Fronts 

    E-print Network

    Rein, Guillermo; Cohen, Simon; Simeoni, Albert

    2009-01-01

    A series of experiments of shallow and strong smouldering fronts in boreal peat have been conducted under laboratory conditions to study the CO and CO2 emissions. Peat samples of 100 mm by 100 mm in cross section and 50 ...

  10. 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 geochemistry, such as mercury, are coupled with decomposition changes. In the triplicate hummock cores, the three proxies likewise show long-term similarities, but not at finer resolution. Exploration of these proxies and their relationships to the geochemistry, based on Principal Component Analysis, suggest the 3 proxies are weakly related and respond to different factors. For example, increased bulk density is facilitated by decomposition and loss of structure, but below the water table further compaction is inhibited regardless of further changes in decomposition. CN ratios and light transmission are nearly orthogonal in PCA space, suggesting they are responding to different processes related to decomposition, as well as unaccounted for changes in plant composition. We believe that decomposition is not fully captured by any one proxy, because each proxy records different aspects of the decomposition process. Besides use of multiple cores, we suggest using more than one decomposition proxy in order to provide a more robust understanding of biogeochemical responses of peatlands to past environmental changes.

  11. 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.

  12. 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 ponds, pump stations and treatment facilities. References Skaggs, R. W. 1980. DRAINMOD reference report. Fort Worth, Tex.: USDA-SCS South National Technical Center. Available at: www.bae.ncsu.edu/soil_water/documents/drainmod/chapter1.pdf

  13. Can Peat Fires Produce a Globally Significant Carbon-Isotope Excursion in the Sedimentary Record?

    NASA Astrophysics Data System (ADS)

    Finkelstein, D. B.; Brassell, S. C.; Pratt, L. M.

    2006-12-01

    Causal mechanisms of negative carbon-isotope excursions associated with greenhouse climates has largely overlooked the potential role of biomass burning. Carbon-isotopic ratios (?13C) of vegetation, soil organic matter and peat are significantly lower than atmospheric carbon dioxide (CO2), and thereby provide a source of low 13C CO2 when combusted. A simplified box model is used to represent carbon-isotopic interactions among the atmosphere, vegetation, soil, and shallow and deep ocean in a system open to burial of marine carbonate and organic matter. Fluxes include productivity, respiration, leaf litter, fire, air-sea exchanges, and shallow-deep ocean exchanges. Peat is an independent component (box) that contributes to combustion-derived CO2. Combustion of 0.08% of the peat reservoir per year for one 1000 yrs increases atmospheric CO2 from 2.5x present atmospheric levels (PAL) to 4.6x PAL, and yields a pronounced negative ?13C excursion in the atmosphere (2.4 per mil, ‰), vegetation (2.4‰) and the surface ocean (1.2‰). Release of CO2 initiates a short-term warming of the atmosphere (up to 14.4 °C, with a duration of 1628 years), which is consistent with the magnitude and length of the observed Toarcian excursion event. These results indicate that peat combustion is a plausible mechanism for driving negative ?13C excursions in the rock record, even during times of elevated pCO2, and the magnitude of peat reservoirs in the geological past makes such interpretations all the more viable for driving negative isotopic excursions.

  14. 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.

  15. Sulfur diagenesis in everglades peat and origin of pyrite in coal

    USGS Publications Warehouse

    Altschuler, Z.S.; Schnepfe, M.M.; Silber, C.C.; Simon, F.O.

    1983-01-01

    The pattern of sulfur transformation in peat across the Everglades basin indicates that pyrite formation in organic-rich swamps depends on the use of organic oxysulfur compounds in dissimilatory respiration by sulfur-reducing bacteria. This paragenesis explains the primary distribution of sulfur compounds in low-sulfur coals and possibly in most coals and many organic-rich soils and sediments. It also accounts for the occurrence of framboidal pyrite bound in fossil tissue in coal and sediments.

  16. Effects of Nutrient Enrichment on Microbial Communities and Carbon Cycling in Wetland Soils

    NASA Astrophysics Data System (ADS)

    Hartman, W.; Neubauer, S. C.; Richardson, C. J.

    2013-12-01

    Soil microbial communities are responsible for catalyzing biogeochemical transformations underlying critical wetland functions, including cycling of carbon (C) and nutrients, and emissions of greenhouse gasses (GHG). Alteration of nutrient availability in wetland soils may commonly occur as the result of anthropogenic impacts including runoff from human land uses in uplands, alteration of hydrology, and atmospheric deposition. However, the impacts of altered nutrient availability on microbial communities and carbon cycling in wetland soils are poorly understood. To assess these impacts, soil microbial communities and carbon cycling were determined in replicate experimental nutrient addition plots (control, +N, +P, +NP) across several wetland types, including pocosin peat bogs (NC), freshwater tidal marshes (GA), and tidal salt marshes (SC). Microbial communities were determined by pyrosequencing (Roche 454) extracted soil DNA, targeting both bacteria (16S rDNA) and fungi (LSU) at a depth of ca. 1000 sequences per plot. Wetland carbon cycling was evaluated using static chambers to determine soil GHG fluxes, and plant inclusion chambers were used to determine ecosystem C cycling. Soil bacterial communities responded to nutrient addition treatments in freshwater and tidal marshes, while fungal communities did not respond to treatments in any of our sites. We also compared microbial communities to continuous biogeochemical variables in soil, and found that bacterial community composition was correlated only with the content and availability of soil phosphorus, while fungi responded to phosphorus stoichiometry and soil pH. Surprisingly, we did not find a significant effect of our nutrient addition treatments on most metrics of carbon cycling. However, we did find that several metrics of soil carbon cycling appeared much more related to soil phosphorus than to nitrogen or soil carbon pools. Finally, while overall microbial community composition was weakly correlated with soil carbon cycling, our work did identify a small number of individual taxonomic groups that were more strongly correlated with soil CO2 flux. These results suggest that a small number of microbial groups may potentially serve as keystone taxa (and functional indicators), which simple community fingerprinting approaches may overlook. Our results also demonstrate strong effects of soil phosphorus availability on both microbial communities and soil carbon cycling, even in wetland types traditionally considered to be nitrogen limited.

  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. Mangrove peat analysis and reconstruction of vegetation history at the Pelican Cays, Belize

    USGS Publications Warehouse

    McKee, K.L.; Faulkner, P.L.

    2000-01-01

    The substrate beneath mangrove forests in the Pelican Cays complex is predominately peat composed mainly of mangrove roots. Leaves and wood account for less than 20% of the peat mass. At Cat Cay, the depth of the peat ranges from 0.2 m along the shoreline to 1.65 m in the island center, indicating that the island has expanded horizontally as well as vertically through below-ground, biogenic processes. Mangrove roots thus play a critical role in the soil formation, vertical accretion, and stability of these mangrove cays. The species composition of fossil roots changes markedly with depth: Rhizophora mangle (red mangrove) was the initial colonizer on a coral base, followed by Avicennia germinans (black mangrove), which increased in abundance and expanded radially from the center of the island. The center of the Avicennia stand ultimately died, leaving an unvegetated, shallow pond. The peat thus retains a record of mangrove development, succession, and deterioration in response to sea-level change and concomitant hydroedaphic conditions controlling dispersal, establishment, growth, and mortality of mangroves on oceanic islands in Belize.

  19. Responsible management of peatlands in Canada, from peat industry to oil sands

    NASA Astrophysics Data System (ADS)

    Rochefort, Line

    2013-04-01

    Canada harbors one third of the peat resources of the world. Peat is an accumulated organic matter composed of dead and partly decomposed plant material, forming huge deposit through time in wetlands like peatlands and boreal coniferous swamps. Peat is a valuable resource as a growing media and soil amendments, an eco-friendly absorbent, also used as biofilters, for body care and for wastewater treatment. Peatlands also offer valuable ecological services : for example, they are the most efficient terrestrial ecosystem to store carbon on a long-term basis. Their ability to "cool off" the planet warrants a good look at their management. The horticultural peat industry of Canada has invested 22 years in R&D in habitat restoration and is now a strong leader in managing industrial peatlands in a sustainable way. The oil sand industry, which is strongly impacting the wetland landscapes of northern Canada, does realize that it has to reduce its ecological footprint, which is heavily criticized around the world. Decommissioned open mines near Fort McMurray have already begun recreating peatland ecosystems, and some restoration attempts of former oil pads are underway in the Peace River region. But the restoration of the largely disturbed wetland landscape of the oil sands is commanding innovative solutions.

  20. 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 surface of the bog presented higher humification degree in the northern part and where the peat is shallower. The lowest values are in the steeper regions and on the borders of the bog, while intermediate classes can be found in the area of the raised basin. The study was implemented using open source software, in particular GRASS and R.

  1. 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.

  2. Contributions of organic matter and organic sulfur redox processes to electron flow in anoxic incubations of peat

    NASA Astrophysics Data System (ADS)

    YU, Zhiguo; Peiffer, Stefan; Göttlicher, Jörg; Knorr, Klaus-Holger

    2015-04-01

    Anaerobic decomposition of peat soils involves a number of interdependent microbial processes that ultimately generate CO2 and CH4. In many peat soils, a high ratio of CO2:CH4 was reported, which presumably results from a direct or indirect role of soil organic matter serving as an electron acceptor. Therefore, in this study we intended to test the hypothesis that organic matter (OM) suppresses methanogenesis and sustains anaerobic CO2 production, serving as i) direct electron acceptor or ii) via supporting internal sulfur cycling to maintains CO2 production through bacterial sulfate reduction (BSR). We incubated peat samples of commercial bog peat, inoculated with a small amount of fresh peat to introduce an active microbial community. Samples were amended with sulfate or sulfide and incubated under anoxic conditions for 6 weeks at 30 ° C. Upon anaerobic incubation of peat virtually devoid of inorganic electron acceptors, CO2 and CH4 were produced at a ratio of 3.2. According to the electron budget, the calculated electron accepting capacity (EAC) of OM was 2.36 ?eq cm3 d-1. Addition of sulfate significantly increased CO2 production and effectively suppressed CH4 production. After subtracting the EAC provided though sulfate addition (0.97~2.81 ?eq cm-3 d-1), EACs supplied by OM reached 3.88 to 4.85 ?eq cm-3 d-1.The contribution of organic sulfur was further evaluated by XANES spectroscopy and using natural abundance of ?34S as a tracer. Results demonstrated that BSR involved both addition of H2S and sulfate to OM leading to a formation of reduced organic sulfur and partial changes of oxidized organic sulfur species. The original peat prior to incubation contained 70.5% reduced organic S (R-S-H, R-S-R, R-S-S-R), and 25.9% oxidized S (R-SO3, R-SO2-R, R-SO4-R), whereas the treatment with H2S or sulfate addition comprised 75.7~ 81.1% reduced organic S, and only 21.1~18.9 % oxidized S. Our results imply that that organic matter contributes to anaerobic respiration i) directly by electron accepting capacity of redox active functional groups ii) directly by oxidized organic sulfur and iii) indirectly by recycling of sulfide to maintain BSR. Moreover, investigating the stability of organic sulfur compounds in peat soil towards abiotic and biotic reduction and oxidation is essential for the understanding of environmental sulfur cycling in anaerobic systems. Keywords: Methanogenesis; Electron transfer; organic sulfur; Redox processes; Freshwater systems;

  3. Development and Carbon Fluxes of Tropical Peat Domes

    NASA Astrophysics Data System (ADS)

    Cobb, A.; Hoyt, A.; Gandois, L.; Su'ut, N. S.; Abu Salim, K.; Ali Ahmad, J.; Jalil, J.; Yussof, M.; Harvey, C.

    2014-12-01

    Tropical peatlands hold large carbon stocks and their degradation has led to large fluxes of carbon dioxide to the atmosphere, from peat decomposition and fires. Existing lumped and steady-state peatland models do not address the development and dynamics of tropical peatlands on the spatial scale of peat domes and time scales of their hydrological response. Our distributed model for tropical peat dynamics, parameterized by measurements in Brunei Darussalam, show that tropical peat domes approach a solution to Poisson's equation as they grow. They approach this stable topography centripetally from the boundaries, so that rates of carbon upake are proportional to the area of the growing interior. Exponentially greater drainage at higher water table leads to strong dependence of peat accumulation or loss on variability of rainfall. Our findings imply a fundamental link between statistics of climate, hydrological properties of peat, metrics of peat landscape topography, and dynamics of carbon sequestration and release.

  4. Upland Log Volumes and Conifer Establishment Patterns in Two Northern,

    E-print Network

    Upland Log Volumes and Conifer Establishment Patterns in Two Northern, Upland Old-Growth Redwood conifer recruit densities on these logs and on the surrounding forest floor. We report significantly greater conifer recruit densities on log substrates as compared to the forest floor. Log substrate

  5. Adsorption and transport of pyrithiobac in soils 

    E-print Network

    Matocha, Christopher John

    1996-01-01

    adsorbents (Gonzales bentonite, Georgia kaolinite, goethite, and Michigan peat) and four soils (Houston Black c, Hidalgo sl, Orelia scl, and Ships sic) having a wide range of physical and chemical properties. Adsorption isotherms were developed...

  6. Water Infiltration and Permeability of Selected Urban Soils as Affected by Salinity and Sodicity 

    E-print Network

    Miyamoto, S.

    2012-10-05

    into two alluvial soils (Torrifluvents), and two upland soils (Paleorthid and Calciorthid, Aridisols) placed in greenhouse pots. For the first experiment, irrigation solutions simulating the Rio Grande water, city potable water, and two sources of reclaimed...

  7. Modulation of headcut soil erosion in rills due to upstream sediment loads

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Headcut erosion can severely accelerate soil loss in upland concentrated flows and lead to significant soil degradation in agricultural areas. Previous experimental work has demonstrated that actively migrating headcuts display systematic morphodynamic behavior, and impinging jet theory can provide...

  8. Ecosystem response to removal of exotic riparian shrubs and a transition to upland vegetation

    USGS Publications Warehouse

    Reynolds, Lindsay V.; Cooper, David J.

    2011-01-01

    Understanding plant community change over time is essential for managing important ecosystems such as riparian areas. This study analyzed historic vegetation using soil seed banks and the effects of riparian shrub removal treatments and channel incision on ecosystem and plant community dynamics in Canyon de Chelly National Monument, Arizona. We focused on how seeds, nutrients, and ground water influence the floristic composition of post-treatment vegetation and addressed three questions: (1) How does pre-treatment soil seed bank composition reflect post-treatment vegetation composition? (2) How does shrub removal affect post-treatment riparian vegetation composition, seed rain inputs, and ground water dynamics? and (3) Is available soil nitrogen increased near dead Russian olive plants following removal and does this influence post-treatment vegetation? We analyzed seed bank composition across the study area, analyzed differences in vegetation, ground water levels, and seed rain between control, cut-stump and whole-plant removal areas, and compared soil nitrogen and vegetation near removed Russian olive to areas lacking Russian olive. The soil seed bank contained more riparian plants, more native and fewer exotic plants than the extant vegetation. Both shrub removal methods decreased exotic plant cover, decreased tamarisk and Russian olive seed inputs, and increased native plant cover after 2 years. Neither method increased ground water levels. Soil near dead Russian olive trees indicated a short-term increase in soil nitrogen following plant removal but did not influence vegetation composition compared to areas without Russian olive. Following tamarisk and Russian olive removal, our study sites were colonized by upland plant species. Many western North American rivers have tamarisk and Russian olive on floodplains abandoned by channel incision, river regulation or both. Our results are widely applicable to sites where drying has occurred and vegetation establishment following shrub removal is likely to be by upland species.

  9. 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 ?13C 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 ?13C 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 ?13C 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 less favorable climatic conditions during the formation of the alpine fen. The distribution of n-alkanes, n-fatty acids and n-alkan-2-ones demonstrated changes related to vegetational shifts throughout the peat profiles. The source materials included remains from mosses, higher terrestrial plants as well as microbial sources. In the peat of the "Großer Bolchow", contributions from phytoplankton were also identified. Among the alkyl series, the n-alkanes evidenced the highest reliability as biomarkers in the peat deposits. Although combination of the results of the three alkyl series were complementary, in some cases, this approach lead to ambiguities, possibly because of selective preservation of certain lipids during peatification. Thus, to verify the analytical results, they were supplemented with field assessment data. Subjecting the two peats to CuO-oxidation revealed mainly contributions of mosses and grasses. The analysis of the degradation stage of the lignin derivatives supported the decomposition pattern already revealed by the ?13C data and the NMR analysis. In summary, our study confirmed that in peat, changes in biomarker abundance and distribution are in accordance with chemical alterations of the organic matter composition. However, both biomarker abundance and the degradation state of the organic material did not indicate a constant increase of the humification with peat depths but showed clear fluctuations along the core. This is in line with the constantly changing climatic conditions during peat formation that are either favoring or hindering organic matter accumulation.

  10. Thermal diffusivity of peat, sand and their mixtures at different water contents

    NASA Astrophysics Data System (ADS)

    Gvozdkova, Anna; Arkhangelskaya, Tatiana

    2014-05-01

    Thermal diffusivity of peat, sand and their mixtures at different water contents was studied using the unsteady-state method described in (Parikh et al., 1979). Volume sand content in studied samples was 0 % (pure peat), 5, 10, 15, 20, 30, 40, 50, 55 and 62 % (pure sand). Thermal diffusivity of air-dry samples varied from 0.6×10-7m2s-1 for pure peat to 7.0×10-7m2s-1 for pure sand. Adding 5 and 10 vol. % of sand didn't change the thermal diffusivity of studied mixture as compared with that of the pure air-dry peat. Adding 15 % of sand resulted in significant increase of thermal diffusivity by approximately 1.5 times: from 0.6×10-7m2s-1 to 0.9×10-7m2s-1. It means that small amounts of sand with separate sand particles distributed within the peat don't contribute much to the heat transfer through the studied media. And there is a kind of threshold between the 10 and 15 vol. % of sand, after which the continuous sandy chains are formed within the peat, which can serve as preferential paths of heat transport. Adding 20 and 30 % of sand resulted in further increase of thermal diffusivity to 1.3×10-7m2s-1 and 1.7×10-7m2s-1, which is more than two and three times greater than the initial value for pure peat. Thermal diffusivity vs. moisture content dependencies had different shapes. For sand contents of 0 to 40 vol. % the thermal diffusivity increased with water content in the whole studied range from air-dry samples to the capillary moistened ones. For pure peat the experimental curves were almost linear; the more sand was added the more pronounced became the S-shape of the curves. For sand contents of 50 % and more the curves had a pronounced maximum within the range of water contents between 0.10 and 0.25 m3m-3 and then decreased. The experimental k(?) curves, where k is soil thermal diffusivity, ? is water content, were parameterized with a 4-parameter approximating function (Arkhangelskaya, 2009, 2014). The suggested approximation has an advantage of clear physical interpretation: the parameters are (1) the thermal diffusivity of the dry sample; (2) the difference between the highest thermal diffusivity at some optional water content and that of the dry sample; (3) the optional water content at which the thermal diffusivity reaches its maximum; (4) half-width of the peak of the k(?) curve. The increase of sand contents in studied mixtures was accompanied by the increase of the parameters (1), (2) and (4) and the decrease of the parameter (3). References Parikh R.J., Havens J.A., Scott H.D., 1979. Thermal diffusivity and conductivity of moist porous media. Soil Science Society of America Journal 43, 1050-1052. Arkhangel'skaya T.A., 2009. Parameterization and mathematical modeling of the dependence of soil thermal diffusivity on the water content. Eurasian Soil Science 42 (2), 162-172. doi: 10.1134/S1064229309020070 Arkhangelskaya T.A., 2014. Diversity of thermal conditions within the paleocryogenic soil complexes of the East European Plain: The discussion of key factors and mathematical modeling // Geoderma. Vol. 213. P. 608-616. doi 10.1016/j.geoderma.2013.04.001

  11. Organic Matter Transformation in the Peat Column at Marcell Experimental Forest: Humification and Vertical Stratification

    SciTech Connect

    Tfaily, Malak; Cooper, Bill; Kostka,; Chanton, Patrick R; Schadt, Christopher Warren; Hanson, Paul J; Iversen, Colleen M; Chanton, Jeff P

    2014-01-01

    A large-scale ecosystem manipulation (Spruce and Peatland Responses under Climatic and Environmental Change, SPRUCE) is being constructed in the Marcell Experimental Forest, Minnesota, USA, to determine the effects of climatic forcing on ecosystem processes in northern peatlands. Prior to the initiation of the manipulation, we characterized the solid-phase peat to a depth of 2 meters using a variety of techniques, including peat C:N ratios, 13C and 15N isotopic composition, Fourier Transform Infrared (FT IR), and 13C Nuclear Magnetic Resonance spectroscopy (13C NMR). FT IR determined peat humification-levels increased rapidly between and 75 cm, indicating a highly reactive zone. We observed a rapid drop in the abundance of O-alkyl-C, carboxyl-C, and other oxygenated functionalities within this zone and a concomitant increase in the abundance of alkyl- and nitrogen-containing compounds. Below 75-cm, minimal change was observed except that aromatic functionalities accumulated with depth. Incubation studies revealed the highest methane production rates and greatest CH4:CO2 ratios within this and 75 cm zone. Hydrology and surface vegetation played a role in belowground carbon cycling. Radiocarbon signatures of microbial respiration products in deeper porewaters resembled the signatures of dissolved organic carbon rather than solid phase peat, indicating that more recently photosynthesized organic matter fueled the bulk of subsurface microbial respiration. Oxygen-containing functionalities, especially O-alkyl-C, appear to serve as an excellent proxy for soil decomposition rate, and in addition should be a sensitive indicator of the response of the solid phase peat to the climatic manipulation.

  12. Population density and total biomass of microbial communities in chestnut soils and solonetzes of the dry steppe zone in the Lower Volga region

    NASA Astrophysics Data System (ADS)

    Kashirskaya, N. N.; Khomutova, T. E.; Chernysheva, E. V.; El'tsov, M. V.; Demkin, V. A.

    2015-03-01

    The population density and total biomass of microbial communities were determined in chestnut soils and solonetzes of the dry steppe zone in the Lower Volga region with the use of the methods of sequential fractionation of the soil and direct counting. The mean weighted values of the population density of the microbial communities in the soil profiles (A1 + B1 + B2 horizons) in the studied soils varied within 3.8-8.0 × 1011 cells/g of soil. The total microbial biomass in the soils of the Privolzhskaya Upland reached 0.9-2.4 mg C/g of soil; in the soils of the Ergeni Upland, it was 20 to 75% lower. The microbial cells in the soils of the Privolzhskaya Upland were larger than those in the soils of the Ergeni Upland. Sequential fractionation of the soil prior to direct counting contributed to the more complete assessment of the population density of the microbial communities.

  13. Interpolations of groundwater table elevation in dissected uplands.

    PubMed

    Chung, Jae-won; Rogers, J David

    2012-01-01

    The variable elevation of the groundwater table in the St. Louis area was estimated using multiple linear regression (MLR), ordinary kriging, and cokriging as part of a regional program seeking to assess liquefaction potential. Surface water features were used to determine the minimum water table for MLR and supplement the principal variables for ordinary kriging and cokriging. By evaluating the known depth to the water and the minimum water table elevation, the MLR analysis approximates the groundwater elevation for a contiguous hydrologic system. Ordinary kriging and cokriging estimate values in unsampled areas by calculating the spatial relationships between the unsampled and sampled locations. In this study, ordinary kriging did not incorporate topographic variations as an independent variable, while cokriging included topography as a supporting covariable. Cross validation suggests that cokriging provides a more reliable estimate at known data points with less uncertainty than the other methods. Profiles extending through the dissected uplands terrain suggest that: (1) the groundwater table generated by MLR mimics the ground surface and elicits a exaggerated interpolation of groundwater elevation; (2) the groundwater table estimated by ordinary kriging tends to ignore local topography and exhibits oversmoothing of the actual undulations in the water table; and (3) cokriging appears to give the realistic water surface, which rises and falls in proportion to the overlying topography. The authors concluded that cokriging provided the most realistic estimate of the groundwater surface, which is the key variable in assessing soil liquefaction potential in unconsolidated sediments. PMID:22107357

  14. Airborne Ground Penetrating Radar (GPR) for peat analyses in the Canadian Northern wetlands study

    NASA Technical Reports Server (NTRS)

    Pelletier-Travis, Ramona E.

    1991-01-01

    The study was conducted as part of the NASA Biospherics Research on Emissions from Wetlands (BREW) program. An important aspect of the program is to investigate the terrestrial production and atmospheric distribution of methane and other gases contributing to global warming. Multi-kilometer transects of airborne (helicopter) Ground Penetrating Radar (GPR) data were collected periodically along the 100 km distance from the coast inland so as to obtain a regional trend in peat depth and related parameters. Global Positioning System (GPS) data were simultaneously collected from the helicopter to properly georeference the GPR data. Additional 50 m ground-based transects of GPR data were also collected as a source of ground truthing, as a calibration aid for the airborne data sets, and as a source of higher resolution data for characterizing the strata within the peat. In situ peat depth probing and soil characterizations from excavated soil pits were used to verify GPR findings. Results from the ground-based data are presented.

  15. Compositional and functional stability of aerobic methane consuming communities in drained and rewetted peat meadows.

    PubMed

    Krause, Sascha; Niklaus, Pascal A; Badwan Morcillo, Sara; Meima Franke, Marion; Lüke, Claudia; Reim, Andreas; Bodelier, Paul L E

    2015-11-01

    The restoration of peatlands is an important strategy to counteract subsidence and loss of biodiversity. However, responses of important microbial soil processes are poorly understood. We assessed functioning, diversity and spatial organization of methanotrophic communities in drained and rewetted peat meadows with different water table management and agricultural practice. Results show that the methanotrophic diversity was similar between drained and rewetted sites with a remarkable dominance of the genus Methylocystis. Enzyme kinetics depicted no major differences, indicating flexibility in the methane (CH4) concentrations that can be used by the methanotrophic community. Short-term flooding led to temporary elevated CH4 emission but to neither major changes in abundances of methane-oxidizing bacteria (MOB) nor major changes in CH4 consumption kinetics in drained agriculturally used peat meadows. Radiolabeling and autoradiographic imaging of intact soil cores revealed a markedly different spatial arrangement of the CH4 consuming zone in cores exposed to near-atmospheric and elevated CH4. The observed spatial patterns of CH4 consumption in drained peat meadows with and without short-term flooding highlighted the spatial complexity and responsiveness of the CH4 consuming zone upon environmental change. The methanotrophic microbial community is not generally altered and harbors MOB that can cover a large range of CH4 concentrations offered due to water-table fluctuations, effectively mitigating CH4 emissions. PMID:26449384

  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.

    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, ?13C and ?15N 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 ?15N 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 to changes in hydrology of the bogs. Significant correlations with polysaccharide and aliphatic pyrolysis products were found for C / N ratios, FTIR-band intensities and for hydrogen index values, supporting that these decomposition indices provide reasonable information despite their bulk nature. Correlation with oxygen index values and ?13C was weaker assumingly indicating carboxylation of the peat during drier periods and enrichment of isotopically lighter peat components during decomposition, respectively. FTIR, C / N ratio, Pyrolysis-GC-MS analyses and Rock Eval hydrogen indices appear to reflect mass loss and related changes in the molecular peat composition during mineralization best. Different to the other investigated proxies, Pyrolysis-GC-MS and FTIR analyses allow disentangling decomposition processes and vegetation changes. UV-ABS measurements of alkaline peat extracts show only weak correlation with other decomposition proxiesas they mainly reflect the formation of humic acids through humifcation and to a~lesser extend mass loss during mineralization.

  17. 75 FR 70221 - City of Upland Public Works Department; Notice of Application Accepted for Filing, Soliciting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-17

    ... Energy Regulatory Commission City of Upland Public Works Department; Notice of Application Accepted for.... Applicant: City of Upland Public Works Department. e. Name of Project: Upland Hydrogeneration Project, ``Hydrogenerator No. 1.'' f. Location: Northwest of the City of Upland, San Bernardino County, California. g....

  18. Soil Science Society of America Journal Soil Sci. Soc. Am. J. 76:23272341

    E-print Network

    Grunwald, Sabine

    , and climatic con- ditions. They cover about 25% of the State of Florida, and the soils in these subtropical in upland systems Jongsung Kim Sabine Grunwald* Univ. of Florida Soil and Water Science Dep. 2169 Mc Conservation Service Florida State Office 2614 N.W. 43rd St. Gainesville, FL 32606 Remote sensing informed soil

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

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

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

  20. Changes in upland wildlife habitat on farmland in Illinois 1920-1987

    USGS Publications Warehouse

    Ribic, C.A.; Warner, R.E.; Mankin, P.C.

    1998-01-01

    An index of upland wildlife habitat was developed to investigate patterns and changes in habitat over time, using four years (1920, 1940, 1964, 1987) and the state of Illinois as an example. The index was composed of two subdivisions that described, at the county level, the quantity of wildlife habitat and a third subdivision that described farming disturbances that impacted the quality of the habitat. Data came from the US Census of Agriculture. The first subdivision that reflected quantity of habitat was called the wildlife habitat subdivision and was the sum of percentage woodland on farms, percentage farmland in nonrow crops, and percentage farmland in set-aside programs. The second subdivision that reflected the quantity of habitat was termed the soil-related features subdivision and was the sum of the percentage of farmland that was not highly erodible, the percentage of farmland in soil-protecting crops, and the percentage of farmland in conservation tillage. The third subdivision, reflecting the quality of the habitat, was the farming disturbance subdivision and was the sum of the percentage of grazing and the percentage of land on which fertilizers, pesticides, and herbicides were applied. Overall, major decreases occurred between 1920 and 1987 in the subdivisions reflecting the quantity of wildlife habitat and a major increase occurred in the subdivision associated with farming disturbance, reflecting the intensification of agriculture in the state. However, there was variability throughout the state, with some counties being more favorable to wildlife (as measured by the subdivisions) than others. Most of the changes within the state for the subdivisions reflecting quantity of upland wildlife habitat occurred during 1940 while changes in the farming disturbance subdivision (reflecting habitat quality) occurred in 1964. By 1987, the western and southern parts of Illinois were the most favorable for wildlife as reflected in all three subdivisions. Upland wildlife harvest indices were related to the subdivisions in 1964 and 1987, when harvest indices were available. Cottontail and northern bobwhite harvests were higher in counties with higher amounts of the wildlife habitat subdivision in both years. Cottontail harvest was also higher in counties with lower levels of the farming disturbance subdivision in 1964 and higher levels of soil-related features subdivision in 1987. Indices at the county level have the potential to be used in a multiscale analysis to investigate the impact of policy changes on large- scale areas of the Midwest and to develop regional perspectives of the impacts of agriculture on upland wildlife and their habitats.

  1. Impacts of Land Cover Change on the Carbon Dynamics in Indonesian Tropical Forested Wetlands- Mangroves and Peat Swamp Forests

    NASA Astrophysics Data System (ADS)

    Kauffman, J. B.; Arifanti, V. B.; Basuki, I.; Kurnianto, S.; Novita, N.; Murdiyarso, D.

    2014-12-01

    Tropical wetland forests including mangroves and lowland peat swamp forests contain among the highest carbon stocks of any ecosystem on the planet. This is largely due to the accumulation of deep organic rich soils which have been sequestering carbon for millennia. Depth of organic layers (peats) can exceed 3 m in mangrove and 10 m in the peat swamp forests. The ecosystem carbon stocks may exceed 2000 Mg/ha in mangroves and 5000 Mg/ha in peat swamp forests. Ironically, rates of deforestation of these tropical forests are among the highest in the tropics. With land cover change comes dramatic shifts in carbon stocks, net ecosystem productivity, and greenhouse gas emissions. Land cover change results in carbon losses of practically all aboveground pools as well as losses arising from soil pools. Based upon studies where we have compared stock changes due to land use the carbon emissions arising from land cover change to shrimp ponds and oil palm have ranged from 800-3000 Mg CO2e/ha. The lowered carbon sequestration rates coupled with increased or similar emissions from decomposition results in an ecosystem shift from a carbon sink to a carbon source. Clearly the large carbon stocks, high rates of deforestation, and large emissions resulting from their degradation suggest that these ecosystems should receive great consideration in climate change mitigation and adaptation strategies.

  2. 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.

  3. 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.

  4. A Parameterized Model for Peat Formation and Water Table Dynamics in Tropical Peat Swamp Forests of Brunei Darussalam

    NASA Astrophysics Data System (ADS)

    Cobb, A.; Gandois, L.; Hoyt, A.; Abu Salim, K.; Yussof, M.; Jalil, J.; Ali Ahmad, J.; Suut, N.; Harvey, C. F.

    2013-12-01

    In tropical peat swamp forests carbon sequestration and emission are tightly coupled to hydrological processes. Little is know about how these processes operate under natural conditions because few undisturbed peat forests remain. We present a combined groundwater-decomposition model of tropical peat forest parameterized by two years of field measurements from two field sites in Brunei Darussalam. The measurements at these sites, one pristine and one deforested but not drained, include continuous water table, throughfall and rainfall data. The model represents hourly shifts in the water table elevation driven by rainfall, runoff and evaporation and combines these hydrologic components with a representation of the peat surface texture and decay rates of both exposed and saturated peat. By linking these small-scale processes to kilometer scale flow, the model reproduces the growth of large, approximately parabolic peat domes over millennia.

  5. Soil Core Sample #1

    USGS Multimedia Gallery

    Soil core obtained from existing goose grazing lawn along the Smith River in the Teshekpuk Lake Special Area of the National Petroleum Reserve - Alaska.  The buried layer of peat beneath goose grazing lawn demonstrates that vegetation change has occurred in this area....

  6. Methylmercury and total mercury in plant litter decomposing in upland forests and flooded landscapes.

    PubMed

    Hall, Britt D; St Louis, Vincent L

    2004-10-01

    The overall objectives of this study were to examine the effects of flooding on the decomposition and mercury (Hg) content of tissues from plants common to boreal upland forests at the Experimental Lakes Area in northwestern Ontario. We used litterbags to study changes in total Hg (THg), methyl Hg (MeHg), carbon (C), and nitrogen (N) in 12 different plant tissues (birch, alder, blueberry, and Labrador tea leaves, bunchberry plants, jack pine needles, Sphagnum spp., Polytrichum spp., and Pleurozium spp. bryophytes, lichen, and fresh and extensively decomposed wood) placed on unflooded boreal forest soils and in experimentally created reservoirs over an approximately 800 day period. Rates of decomposition (as indicated by differences in the percentage of C and N mass left in the tissues over time) were slower in plant tissues placed on unflooded soils compared to the same tissues that were inundated in reservoirs. Depending on tissue type and initial THg concentrations, decomposing litter on both unflooded and flooded soils was either a source or a sink for THg. Tissues where initial THg concentrations were greater than 30 ng g(-1) represented a source of THg to the surrounding environment, whereas tissues that had initial concentrations of less than 30 ng g(-1) gained THg mass. Initial rates of change in THg were more rapid in plant tissues placed in reservoirs compared to the same plant tissue placed on unflooded soils, but there were no differences in final THg masses after approximately 800 days. Plant tissues placed in reservoirs exhibited large increases in MeHg mass, whereas MeHg mass decreased in the same plants placed on unflooded soils. This is the first study examining THg and MeHg cycling in decomposing plants in upland boreal forests and reservoirs. PMID:15506193

  7. 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, ?13C and ?15N 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 ?15N 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 composition 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 than polysaccharides or aliphatics, and presumably reflects changes in vegetation associated with changes in hydrology of the bogs. Significant correlations with polysaccharide and aliphatic pyrolysis products were found for C / N ratios, FTIR-band intensities and for hydrogen index values, supporting that these decomposition indices provide reasonable information. Correlations of polysaccharide and aliphatic pyrolysis products with oxygen index values and ?13C was weaker, assumingly indicating carboxylation of the peat during drier periods and enrichment of isotopically lighter peat components during decomposition, respectively. FTIR, C / N ratio, pyrolysis-GC-MS analyses and Rock Eval hydrogen indices appear to reflect mass loss and related changes in the molecular peat composition during mineralization best. Pyrolysis-GC-MS allows disentangling the decomposition processes and vegetation changes. UV-ABS measurements of alkaline peat extracts show only weak correlation with other decomposition proxies and pyrolysis results as they mainly reflect the formation of humic acids through humification and to a lesser extent mass loss during mineralization.

  8. Impacts of livestock in regenerating upland birch woodlands in Scotland 

    E-print Network

    Pollock, Meg L; Milner, J M; Waterhouse, A; Holland, J P; Legg, Colin

    2005-01-01

    Including large herbivores in wooded areas is often seen as a useful conservation tool. Browsing intensities on saplings in seven upland birch woodlands grazed by sheep, cattle and wild herbivores were studied. The aims ...

  9. Arizona Upland Plant Community in the Sonoran Desert

    USGS Multimedia Gallery

    In the drier Arizona upland plant communities, pictured here, some species will likely decline with forecasted climate change (such as foothill paloverde, ocotillo and creosote bush) while cacti may well increase in abundance and range....

  10. Responses of Isolated Wetland Herpetofauna to Upland Forest Management

    SciTech Connect

    Russell, K.R.; Hanlin, H.G.; Wigley, T.B.; Guynn, D.C., Jr.

    2002-01-02

    Measurement of responses of herpetofauna at isolated wetlands in the Coastal Plain of South Carolina to disturbance of adjacent loblolly pine forest. Many species of isolated wetland herpetofauna in the Southeastern Coastal Plain may tolerate some disturbance in adjacent upland stands. Responses of isolated wetland herpetofauna to upland silviculture and the need for adjacent forested buffers likely depend on the specific landscape context in which the wetlands occur and composition of the resident herpetofaunal community.

  11. Usual and unusual CIELAB color parameters for the study of peat organic matter properties: Tremoal do Pedrido bog (NW Spain)

    NASA Astrophysics Data System (ADS)

    Sanmartín, P.; Silva-Sánchez, N.; Martínez-Cortizas, A.; Prieto, B.

    2015-04-01

    We have tested the practical application of color measurements in the study of organic matter properties (C and N content, C/N ratios, degree of peat humification-DPH) of a 335 cm long peat core sampled at Tremoal do Pedrido bog. Usual and unusual CIELAB color parameters were measured on samples that were sectioned at high resolution (slices of 1 cm in thickness). The objective of the study is twofold: (i) describe a rapid, cost-effective and non-destructive method of assessing peat properties without the need of extractions and chemical methods and (ii) contribute to further research on applied colorimetry using the well-known CIELAB coordinates: L*, a*, b*, C*ab and hab (‘usual CIELAB color parameters’) and the less well-known CIELAB parameters: [a* x b*], [a*/b*], [(a*/b*) x 1000], [1000 x a*/(L*+ b*)], [2000 x a*/(L* x b*)] and RLab= [a*(a*2+b*2)1/2 1010]/(b* x L*6) (‘unusual CIELAB color parameters’). Our findings show that L* and hab coordinates as well as [(a*/b*) x 1000], [2000 x a*/(L* x b*)] and RLab parameters give the best bivariate Spearman's correlations. Linear regression equations were calculated to predict peat properties from all CIELAB parameters under study and a notable fit (R2: 0.65-0.79) was obtained. The evaluation presented here indicates that the determination of usual and unusual CIELAB parameters offers potential for the study of peat organic matter properties and encourages the routine application of this methodology on other peat cores and organic soils.

  12. Simulated thaw development of a peat plateau-bog complex in a discontinuous permafrost region, Northwest Territories, Canada

    NASA Astrophysics Data System (ADS)

    Kurylyk, Barret; Hayashi, Masaki; Quinton, William; Voss, Clifford

    2015-04-01

    Air temperatures at high latitudes have increased at rates that exceed globally averaged trends, and this warming has produced rapid permafrost degradation in many areas. In discontinuous permafrost regions of the Taiga Plains of northwestern Canada, past climate warming has created a complex landscape mosaic of fully thawed bogs/fens and remnant peat plateaus underlain by thin permafrost. The thawing of peat plateaus can alter the landscape hydrologic connectivity by creating pathways to efficiently convey water from bogs to nearby rivers and lakes. Extensive monitoring of the thermal regime of a peat plateau-bog complex in the Scotty Creek watershed (61.3° N, 121.3° W), Northwest Territories, Canada has identified rapid permafrost degradation in the past decade. In addition, satellite images indicate major landscape evolution due to permafrost thaw since 1970, and these changes have resulted in increased discharge at the watershed outlet. These long term comprehensive data facilitate the numerical modeling of idealized permafrost environments based on observed data. The objective of this research project is to elucidate fundamental processes that contribute to multi-dimensional permafrost thaw and associated hydrological changes in discontinuous permafrost regions. The thaw evolution in this peat plateau-bog complex is simulated using SUTRA, a numerical groundwater flow and coupled heat transport model that has been modified to include dynamic freeze-thaw processes. To accommodate complex surface processes, measured climate data from 1900-2010 are used to drive a separate soil-vegetation-atmosphere energy transfer model. Near-surface temperatures produced by the vertical transfer model for the peat plateau and bog are applied as the upper thermal boundary conditions for the multi-dimensional subsurface heat transport simulations in SUTRA (1900-2010). The simulated thaw development of this peat plateau will be compared to satellite imagery to assess the ability of this sequential modeling approach to reproduce observed permafrost degradation.

  13. Soils

    NASA Astrophysics Data System (ADS)

    Schaetzl, Randall J.; Anderson, Sharon

    2005-06-01

    This comprehensive work on all aspects of soils includes introductory chapters on soil morphology, physics, mineralogy and organisms in anticipation of the more advanced analysis of the subject that follows. Replete with hundreds of high-quality figures and a large glossary, its global perspective makes it an invaluable text for anyone studying soils, landforms and landscape change in middle to upper-level undergraduate and graduate courses.

  14. 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.

  15. Peat bog Records of Atmospheric Dust fluxes - Holocene palaeoenvironmental and paleoclimatic implications for South America

    NASA Astrophysics Data System (ADS)

    De Vleeschouwer, François; Vanneste, Heleen; Bertrand, Sébastien; Coronata, Andrea; Gaiero, Diego; Le Roux, Gael

    2013-04-01

    Little attention has been given to pre-anthropogenic signals recorded in peat bogs, especially in the Southern Hemisphere. Yet they are important to 1/ better understand the different particle sources during the Holocene and 2/ to tackle the linkage between atmospheric dust loads and climate change and 3/ to better understand the impact of dust on Holocene palaeoclimate and palaeoenvironments in a critical area for ocean productivity. In the PARAD project, we will explore the use of a broad range of trace elements and radiogenic isotopes (Pb, Nd, Hf) as dust proxies. Coupling these findings with biological proxies (plant macrofossils, pollen) and detailed age-depth modelling, we expect not only to identify and interpret new links between atmospheric dust chemistry and climate change. In this contribution, we will present the preliminary results on two peat records of natural atmospheric dust using the elemental and isotopic signature in Tierra del Fuego. Preliminary results on two peat sections covering the Holocene (Karukinka Bog, Chile, 8kyrs and Harberton bog, Argentina, 14kyrs) will be discussed. This encompasses density, ash content, elemental and isotopic geochemistry, macrofossil determination and radiocarbon dating. More specifically, Karukinka bog display several mineral peaks, which possible origin (soil particles, volcanism, cosmogenic dusts, marine aerosols…) will be discussed here as well as in Vanneste et al. (this conference, session Aeolian dust: Initiator, Player, and Recorder of Environmental Change).

  16. Tracing origin and fate of dissolved greenhouse gases in Malaysian peat-draining rivers

    NASA Astrophysics Data System (ADS)

    Müller, Denise; Warneke, Thorsten; Rixen, Tim; Denis, Nastassia; Müller, Moritz; Notholt, Justus

    2014-05-01

    Tropical peatlands are known to store large amounts of organic carbon. Peat-draining rivers in these regions receive considerable amounts of carbon from these soils, yet, its fate remains poorly studied. Although a number of recent studies investigated greenhouse gas production and emission from inland waters, only a small number focused on tropical freshwaters, and data from tropical peat-draining rivers are particularly lacking. We investigated rivers in a peat-dominated catchment in Sarawak, Malaysia. Dissolved greenhouse gases (GHG) were measured with Fourier Transform InfraRed (FTIR) spectroscopy. It allows for the simultaneous and continuous measurement of major GHG (CO2 and ?13C in CO2, CH4, N2O, and CO) with high accuracy and precision. We found that concentrations of dissolved CO, CO2 and CH4 were higher than the respective atmospheric equilibrium concentration, suggesting that those rivers are a source of these GHG to the atmosphere. Enhanced N2O concentrations were only found around some cultivated areas. In order to trace the origin of the GHG, we quantified dissolved organic carbon (DOC), particulate organic carbon (POC), inorganic nutrients and different parameters that describe water chemistry. Stable carbon isotope analysis of dissolved inorganic carbon (DIC) yielded indications of a terrestrial source of inorganic carbon in the river, suggesting that in-situ respiration of organic matter might play an important role.

  17. 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.

  18. Peat resources of Maine. Volume 5. Washington 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. Similar DOE/State Peat Resource Evaluation Programs are also being carried out in thirteen other states, including Alaska, Michigan, Minnesota, North Carolina, and South Carolina, whose programs began in 1979. Two hundred thirty-three areas containing peat deposits were evaluated under the Program. A total of 48 deposits covering 14,988 acres and containing 32,114,800 short tons (dry weight) of peat in Washington County have been evaluated under the Maine Peat Resource Evaluation Program. These deposits range in size from 40 to 2645 acres and in estimated resources from 40,000 to 6,953,000 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 50. 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, 50 figures, 3 tables.

  19. 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.

  20. 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.

  1. Origin of Lead in Eight Central European Peat Bogs Determined

    E-print Network

    Wieder, R. Kelman

    Research Origin of Lead in Eight Central European Peat Bogs Determined from Isotope Ratios was identified in 210Pb-dated profiles through eight peat bogs distributed over an area of 60 000 km2. The Sphagnum-dominated bogs were located mainly in mountainous regions of the Czech Republic bordering

  2. Ecological assessment for the wetlands at Milltown Reservoir, Missoula, Montana: Characterization of emergent and upland habitats

    SciTech Connect

    Linder, G. ); Hazelwood, R.; Palawski, D. . Ecological Services)

    1994-12-01

    Wetlands in mining districts in the western US are frequently impacted by heavy metal-contaminated sediments. The present study summarizes a soil contamination evaluation and an ecological assessment completed for a Superfund site located at Milltown Reservoir wetlands (MRW) in western Montana. For wetlands, as well as upland habitats adjacent to wetlands, biological evaluations in the field and laboratory should be considered critical components in the ecological risk assessment process. Depending upon habitat type, field and laboratory methods have been developed for hazard and risk assessment that lend themselves directly to the Superfund ecological risk assessment process, and that consider contaminant bioavailability and subtle expressions of adverse biological effects associated with chronic exposures. As part of an ecological risk assessment for MRW, field surveys and a variety of biological test methods (e.g., terrestrial and aquatic tests) were critical to the wetland evaluation. For evaluating heavy metal effects at MRW, field and laboratory methods within the ecological assessment included wetlands delineation and preliminary plant and wildlife survey; vegetation tests in emergent and upland habitats; soil macroinvertebrate (earthworm) tests; preliminary studies using amphibian and bacterial test systems; soil characterizations; and chemical analysis of soils, sediments, and biological materials. Inn conjunction with chemical analyses, these biological and ecological evaluations yielded an integrated evaluation of ecological effects and exposure at MRW. The data gathered from laboratory and field work at MRW suggested that biological and ecological effects were subtle in their expression in the wetland. In conjunction with sediment contamination evaluations, these studies should reduce the uncertainty associated with the baseline ecological risk assessment for MRW.

  3. 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 (?15N 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 ?15N results at VJ and CB. Data from a variety of peat bogs along pollution and climatic gradients would be needed to test to what extent the record of atmospheric N inputs in peat is overprinted by variable, locally-controlled decomposition rates.

  4. 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.

  5. PEAT ACCRETION HISTORIES DURING THE PAST 6000 YEARS IN MARSHES OF THE SACRAMENTO - SAN JOAQUIN DELTA, CALIFORNIA, USA

    SciTech Connect

    Drexler, J Z; de Fontaine, C S; Brown, T A

    2009-07-20

    Peat cores were collected in 4 remnant marsh islands and 4 drained, farmed islands throughout the Sacramento - San Joaquin Delta of California in order to characterize the peat accretion history of this region. Radiocarbon age determination of marsh macrofossils at both marsh and farmed islands showed that marshes in the central and western Delta started forming between 6030 and 6790 cal yr BP. Age-depth models for three marshes were constructed using cubic smooth spline regression models. The resulting spline fit models were used to estimate peat accretion histories for the marshes. Estimated accretion rates range from 0.03 to 0.49 cm yr{sup -1} for the marsh sites. The highest accretion rates are at Browns Island, a marsh at the confluence of the Sacramento and San Joaquin rivers. Porosity was examined in the peat core from Franks Wetland, one of the remnant marsh sites. Porosity was greater than 90% and changed little with depth indicating that autocompaction was not an important process in the peat column. The mean contribution of organic matter to soil volume at the marsh sites ranges from 6.15 to 9.25% with little variability. In contrast, the mean contribution of inorganic matter to soil volume ranges from 1.40 to 8.45% with much greater variability, especially in sites situated in main channels. These results suggest that marshes in the Delta can be viewed as largely autochthonous vs. allochthonous in character. Autochthonous sites are largely removed from watershed processes, such as sediment deposition and scour, and are dominated by organic production. Allochthonous sites have greater fluctuations in accretion rates due to the variability of inorganic inputs from the watershed. A comparison of estimated vertical accretion rates with 20th century rates of global sea-level rise shows that currently marshes are maintaining their positions in the tidal frame, yet this offers little assurance of sustainability under scenarios of increased sea-level rise in the future.

  6. 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.

  7. 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.

  8. Use of CT imaging to examine the coarse roots, rhizomes, and peat associated with creek bank Spartina alterniflora in fertilized and control creeks in Plum Island (MA)

    EPA Science Inventory

    We used computer-aided tomography (CT) to quantify the wet mass, abundance, and diameter of coarse roots and rhizomes as well as the wet mass and particle density of marsh peat in 7-year fertilized and control creeks in Plum Island (MA). In shallow soils (0 – 10 cm) and at dep...

  9. Assessing the impact of tree plantations on Water and CO2 Cycles in the peat swamp forest, Indonesia

    NASA Astrophysics Data System (ADS)

    Kozan, O.

    2011-12-01

    The rapid deforestation in tropical countries contributes to the increase in the atmospheric concentration of carbon dioxide. On the other hand, the importance of bio-materials will be continuously increasing because of the demand of recyclable resources is increasing for the reduction of the consumption of fossil resources. We are trying to enhance the theoretical and empirical understanding of soil-vegetation -atmosphere exchanges of carbon dioxide (CO2), water (H2O), and energy balance components based on in situ observation and modeling in peat swamp forest, West Kalimantan. Our research targets are following three: 1. To estimate water budget using ground water level, rain gauge and water flux data. 2. To observe Carbon exchange processes (CO2 budget) during and after ecological succession from secondary forest to plantation forest. 3. To propose new method of ground water management to improve timber productivity and to reduce environmental load using observation data and hydrological modeling. CO2 flux monitoring is started cooperate with local company (Pt. WSL) since May 2010. Wetlands ecosystems act as a sink (photosynthetic uptake) and source (due to soil decomposition) of carbon. Our target area is revealed as a net carbon sink in 2010-2011 season. Soil release CO2 into atmosphere, however photosynthetic activity absorption is much more efficient. The amount of CO2 release from peat swamp depends on water level and surface soil moisture. One year observation data is not enough to discuss carbon budget in peat swamp. For example, 2010-2011 season is La Niña (rainy) year in Indonesia. CO2 flux and hydrological observation will be continued until 2015 for understanding long-term carbon budget. Keywords: CO2 Flux, eddy covariance, peat decomposition, hydrological modeling

  10. Respiration fluxes in a paludified shallow-peat spruce forest in the southern taiga of European Russia

    NASA Astrophysics Data System (ADS)

    Kurbatova, Juliya

    2014-05-01

    Soil, tree stems and ecosystem carbon dioxide fluxes were measured by chambers and eddy covariance methods in paludified shallow-peat spruce forest in southern taiga of European Russia (Tver region, 56N 33E) during growing seasons of 2002 - 2012. The site was established in 1998 as part of the EUROSIBERIAN CARBONFLUX project, an international field experiment examining atmosphere-biosphere interaction in Siberia and European Russia. In all of the years the observed annual cumulative net ecosystem flux was positive (the forest was a source of carbon to the atmosphere). Soil and tree stem respiration was a significant part of total ecosystem respiration (ER) in this paludified shallow-peat spruce forest. On average, 49% of ER came from soil respiration. We found that the soil fluxes exhibited high seasonal variability ranging from 0.7 to 10 mkmol m-2s-1. Generally soil respiration depended on soil temperature and ground water level. In drought conditions soil respiration was low and did not depend on temperature. Stem respiration of spruces grew intensively in May, had permanently high values from June to the end of September and in October it dramatically decreased. Tree stem respiration in midsummer was about 3-5 mkmol•m-2s-1 for dominant trees and about 1-2 mkmol•m-2s-1 for subdominant trees. Respiration of living tree stems was about 10-20% of ER.

  11. Peat resources of southern and western Maine. [USA

    SciTech Connect

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

    1983-01-01

    Peat has been used for many years in agriculture and horticulture primarily because of its ability to retain many times its own weight in water. It has also been used as a domestic fuel for hundreds of years. More recently, peat has been used by nations such as Ireland and the Soviet Union to generate electricity. At the present time, virtually all of the peat harvested in the United States is used in agriculture and horticulture. However, in light of the increasing costs of traditional energy sources, peat is being more closely scrutinized as an alternate fuel source. The State of Maine has significant peat resources, and current estimates suggest that there are as many as 6000 to 8000 individual peat deposits comprising a total land area of 500,000 to 750,000 acres. The current resource evaluation was developed to provide a more comprehensive analysis of available peat resources. This report summarizes the work conducted in southern and western Maine under the Maine Peat Resource Evaluation Program. It includes sketch maps, sections and laboratory analyses on which estimates of the resources are based. These data may be utilized to more accurately assesss the energy and agricultural potential of Maine's peatlands. Virtually all peat sold in the United States in 1979 was used for agricultural and horticultural purposes. It was marketed through nurseries, garden centers, and chain stores chiefly in suburban areas of the north-central, northeastern, and middle Atlantic states and Florida. Production during 1980 in the United States was estimated (Searles, 1981) at 790,000 short tons for agricultural use. Value of the 1980 production was about $17,000,000, and the average value per ton was about $21.80. Apparent consumption of peat in the United States during 1980, however, was 1,115,000 short tons, of which imports composed 355,000 short tons.

  12. Metabolic and trophic interactions modulate methane production by Arctic peat microbiota in response to warming

    PubMed Central

    Tveit, Alexander Tøsdal; Urich, Tim; Frenzel, Peter; Svenning, Mette Marianne

    2015-01-01

    Arctic permafrost soils store large amounts of soil organic carbon (SOC) that could be released into the atmosphere as methane (CH4) in a future warmer climate. How warming affects the complex microbial network decomposing SOC is not understood. We studied CH4 production of Arctic peat soil microbiota in anoxic microcosms over a temperature gradient from 1 to 30 °C, combining metatranscriptomic, metagenomic, and targeted metabolic profiling. The CH4 production rate at 4 °C was 25% of that at 25 °C and increased rapidly with temperature, driven by fast adaptations of microbial community structure, metabolic network of SOC decomposition, and trophic interactions. Below 7 °C, syntrophic propionate oxidation was the rate-limiting step for CH4 production; above this threshold temperature, polysaccharide hydrolysis became rate limiting. This change was associated with a shift within the functional guild for syntrophic propionate oxidation, with Firmicutes being replaced by Bacteroidetes. Correspondingly, there was a shift from the formate- and H2-using Methanobacteriales to Methanomicrobiales and from the acetotrophic Methanosarcinaceae to Methanosaetaceae. Methanogenesis from methylamines, probably stemming from degradation of bacterial cells, became more important with increasing temperature and corresponded with an increased relative abundance of predatory protists of the phylum Cercozoa. We concluded that Arctic peat microbiota responds rapidly to increased temperatures by modulating metabolic and trophic interactions so that CH4 is always highly produced: The microbial community adapts through taxonomic shifts, and cascade effects of substrate availability cause replacement of functional guilds and functional changes within taxa. PMID:25918393

  13. Metabolic and trophic interactions modulate methane production by Arctic peat microbiota in response to warming.

    PubMed

    Tveit, Alexander Tøsdal; Urich, Tim; Frenzel, Peter; Svenning, Mette Marianne

    2015-05-12

    Arctic permafrost soils store large amounts of soil organic carbon (SOC) that could be released into the atmosphere as methane (CH4) in a future warmer climate. How warming affects the complex microbial network decomposing SOC is not understood. We studied CH4 production of Arctic peat soil microbiota in anoxic microcosms over a temperature gradient from 1 to 30 °C, combining metatranscriptomic, metagenomic, and targeted metabolic profiling. The CH4 production rate at 4 °C was 25% of that at 25 °C and increased rapidly with temperature, driven by fast adaptations of microbial community structure, metabolic network of SOC decomposition, and trophic interactions. Below 7 °C, syntrophic propionate oxidation was the rate-limiting step for CH4 production; above this threshold temperature, polysaccharide hydrolysis became rate limiting. This change was associated with a shift within the functional guild for syntrophic propionate oxidation, with Firmicutes being replaced by Bacteroidetes. Correspondingly, there was a shift from the formate- and H2-using Methanobacteriales to Methanomicrobiales and from the acetotrophic Methanosarcinaceae to Methanosaetaceae. Methanogenesis from methylamines, probably stemming from degradation of bacterial cells, became more important with increasing temperature and corresponded with an increased relative abundance of predatory protists of the phylum Cercozoa. We concluded that Arctic peat microbiota responds rapidly to increased temperatures by modulating metabolic and trophic interactions so that CH4 is always highly produced: The microbial community adapts through taxonomic shifts, and cascade effects of substrate availability cause replacement of functional guilds and functional changes within taxa. PMID:25918393

  14. Integration of crop rotation and arbuscular mycorrhiza (AM) inoculum application for enhancing AM activity to improve phosphorus nutrition and yield of upland rice (Oryza sativa L.).

    PubMed

    Maiti, Dipankar; Toppo, Neha Nancy; Variar, Mukund

    2011-11-01

    Upland rice (Oryza sativa L.) is a major crop of Eastern India grown during the wet season (June/July to September/October). Aerobic soils of the upland rice system, which are acidic and inherently phosphorus (P) limiting, support native arbuscular mycorrhizal (AM) activity. Attempts were made to improve P nutrition of upland rice by exploiting this natural situation through different crop rotations and application of AM fungal (AMF) inoculum. The effect of a 2-year crop rotation of maize (Zea mays L.) followed by horse gram (Dolichos biflorus L.) in the first year and upland rice in the second year on native AM activity was compared to three existing systems, with and without application of a soil-root-based inoculum. Integration of AM fungal inoculation with the maize-horse gram rotation had synergistic/additive effects in terms of AMF colonization (+22.7 to +42.7%), plant P acquisition (+11.2 to +23.7%), and grain yield of rice variety Vandana (+25.7 to +34.3%). PMID:21448812

  15. Relationships between soil microbial communities and soil carbon turnover along a vegetation and moisture gradient in interior Alaska

    NASA Astrophysics Data System (ADS)

    Waldrop, M. P.; Harden, J. W.; Turetsky, M. R.; Petersen, D. G.; McGuire, A. D.; Briones, M. J.; Churchill, A. C.; Doctor, D. H.; Pruett, L. E.

    2010-12-01

    Boreal landscapes are characterized by a mosaic of uplands and lowlands, which differ in plant species composition, litter biochemistry, and biogeochemical cycling rates. Boreal ecosystems, from upland black spruce stands to lowland fens, are structured largely by water table position and contain quantitatively and qualitatively different forms of soil organic matter. Differences in carbon (C) availability among ecosystems likely translate to differences in the structure of soil microbial communities, which in turn could affect rates of organic matter decomposition and turnover. We examined relationships between microbial communities and soil C turnover in near-surface soils along a topographic soil moisture and vegetation gradient in interior Alaska. We tested the hypothesis that upland black spruce sites would be dominated by soil fungi and have slow rates of C turnover, whereas lowland ecosystems would be dominated by bacteria and mesofauna (enchytraeids) and have more rapid rates of C turnover. We utilized several isotopic measures of soil C turnover including bomb radiocarbon techniques, the ?15N of SOM, and the difference between ?13C of SOM, DOC, and respired CO2. All three measures indicated greater C turnover rates in the surface soils of the lowland fen sites compared to the more upland locations. Quantitative PCR analyses of soil bacteria and archaea, combined with enchytraed counts, confirmed that surface soils from the lowland fen ecosystems had the highest abundances of these functional groups. Fungal biomass was highly variable and tended to be more abundant in the upland forest sites. Soil enzymatic results were mixed: potential cellulase activities were higher in the more upland soils even though rates of microbial activity were generally lower. Oxidative enzyme activities were higher in fens, even though these ecosystems are saturated and partly anaerobic. Overall our data support soil food web theory which argues that rapidly cycling systems are bacterial dominated with mesofaunal grazing, whereas slowly cycling systems have characteristic higher fungal:bacterial ratios.

  16. Phenological assessment in the Owhyee Uplands: integrating climate drivers and ecological response at local to regional scales

    NASA Astrophysics Data System (ADS)

    Torregrosa, A.; Hanser, S.; Tumbusch, M. L.; Bedford, D.

    2009-12-01

    The seasonal cycle of vegetation change in biomass, structure, and composition is a dominant landscape feature influencing many ecosystem components of the Owyhee Uplands particularly resident and migratory vertebrates and invertebrates. Encompassing portions of Idaho, Nevada, and Oregon, the Owyhee Uplands have remained relatively intact with climate, exotic plant invasions, and anthropogenic agents, such as grazing, acting as the principle causes of ecosystem stress. The sagebrush habitats of the Owyhee Uplands are a stronghold for several federal and state species of special concern, including the Greater sage-grouse (Centrocercus urophasianus). We examined phenological variation in response to climate conditions such as temperature, relative humidity, precipitation, soil moisture, solar irradiance, and snowfall at a range of spatial and temporal scales across a gradient of soil and landforms. We integrated/analyzed measures of greenness derived from ground-based cameras and several satellite sensors (AVHRR, MODIS, and Landsat), early and late season field-collected measures of plant species cover and passerine bird diversity and abundance, daily measurement of soil moisture conditions from in-situ sensors, site-level snow depth conditions from thermochron fitted snow poles, and climate conditions derived from a combination of site-based meteorological stations and interpolated PRISM data. Our objectives include 1) quantifying covariation between greenness-climate-soil-snow conditions and vertebrate and plant species phenology, 2) spatial interscale comparisons of the covariation, and 3) recommendations for on-going data collection and analysis methods to explore phenological response within the context of the natural range of variability and under climate change scenarios.

  17. 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.

  18. Peat resources of Maine. Volume 3. Piscataquis and Somerset Counties

    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 49 deposits covering 12,952 acres and containing 22,683,000 short tone (dry weight) of peat in Piscataquis and Somerset Counties have been evaluated under the Maine Peat Resource Evaluation Program. These deposits range in size from 27 to 1344 acres and in estimated resources from 37,800 to 3,204,800 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 52. 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, 52 figures, 3 tables.

  19. 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.

  20. Peat resources of Maine. Volume 1. Aroostook 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 42 deposits covering 11,498 acres and containing 18,851,400 short tons (dry weight) of peat in Aroostook County have been evaluated under the Maine Peat Resource Evaluation Program. These deposits range in size from 30 to 1936 acres and in estimated resources from 48,000 to 3,872,000 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 4-41. Cores showing the vertical distribution of peat and sediments as well as sample locations, and results of laboratory analyses are also included. 22 references, 41 figures, 3 tables.

  1. Peat resources of Maine. Volume 4. Southern and western Maine

    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 46 deposits covering 11,853 acres and containing 21,930,200 short tone (dry weight) of peat in southern and western Maine have been evaluated under the Main Peat Resource Evaluation Program. These deposits range in size from 55 to 732 acres and in estimated resources from 55,000 to 1,864,000 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 49. 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, 45 figures, 3 tables.

  2. History of atmospheric trace metal deposition along the St. Lawrence Valley (Quebec) using peat bog

    E-print Network

    History of atmospheric trace metal deposition along the St. Lawrence Valley (Quebec) using peat bog and peat bogs. Among these archives, peat bogs have proven to be effective in reconstructing the history three peat bogs along the St. Lawrence Valley. Core chronologies were established using 210 Pb

  3. SYNTHESIS OF WESTERN WILLET (Catoptrophorus semipalmatus inornatus) MARBLED GODWIT (Limosa fedoa), AND UPLAND SANDPIPER (Bartramia

    E-print Network

    SYNTHESIS OF WESTERN WILLET (Catoptrophorus semipalmatus inornatus) MARBLED GODWIT (Limosa fedoa semipalmatus inornatus) MARBLED GODWIT (Limosa fedoa), AND UPLAND SANDPIPER (Bartramia longicauda) RESEARCH semipalmatus inornatus) MARBLED GODWIT (Limosa fedoa), AND UPLAND SANDPIPER (Bartramia longicauda) RESEARCH

  4. 78 FR 34374 - Notice of Availability of Final Revisions to the Upland Erosion Control, Revegetation, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-07

    ...Availability of Final Revisions to the Upland Erosion Control, Revegetation, and Maintenance...Energy Projects has revised its Upland Erosion Control, Revegetation, and Maintenance...baseline mitigation measures for minimizing erosion, enhancing revegetation, and...

  5. 77 FR 47063 - Notice of Availability of Draft Revisions; Upland Erosion Control, Revegetation, and Maintenance...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-07

    ...Availability of Draft Revisions; Upland Erosion Control, Revegetation, and Maintenance...Energy Projects is revising its Upland Erosion Control, Revegetation, and Maintenance...baseline mitigation measures for minimizing erosion and enhancing revegetation in...

  6. Atmospheric Deposition of Trace Elements in Ombrotrophic Peat as a Result of Anthropic Activities

    NASA Astrophysics Data System (ADS)

    Fabio Lourençato, Lucio; Cabral Teixeira, Daniel; Vieira Silva-Filho, Emmanoel

    2014-05-01

    Ombrotrophic peat can be defined as a soil rich in organic matter, formed from the partial decomposition of vegetable organic material in a humid and anoxic environment, where the accumulation of material is necessarily faster than the decomposition. From the physical-chemical point of view, it is a porous and highly polar material with high adsorption capacity and cation exchange. The high ability of trace elements to undergo complexation by humic substances happens due to the presence of large amounts of oxygenated functional groups in these substances. Since the beginning of industrialization human activities have scattered a large amount of trace elements in the environment. Soil contamination by atmospheric deposition can be expressed as a sum of site contamination by past/present human activities and atmospheric long-range transport of trace elements. Ombrotrophic peat records can provide valuable information about the entries of trace metals into the atmosphere and that are subsequently deposited on the soil. These trace elements are toxic, non-biodegradable and accumulate in the food chain, even in relatively low quantities. Thus studies on the increase of trace elements in the environment due to human activities are necessary, particularly in the southern hemisphere, where these data are scarce. The aims of this study is to evaluate the concentrations of mercury in ombrotrophic peat altomontanas coming from atmospheric deposition. The study is conducted in the Itatiaia National Park, Brazilian conservation unit, situated between the southeastern state of Rio de Janeiro, São Paulo and Minas Gerais. An ombrotrophic peat core is being sampled in altitude (1980m), to measure the trace elements concentrations of this material. As it is conservation area, the trace elements found in the samples is mainly from atmospheric deposition, since in Brazil don't exist significant lithology of trace elements. The samples are characterized by organic matter content which is determined by calcination and pH. For the determination of mercury, an aliquot of 10 mL of sample with 5 mL of the reducing agent 2 % SnCl2, purged with air by atomic absorption spectrophotometry by cold vapor, EAAVF is being used. The determination of other trace elements (Zn, Cd and Pb) is analyzed by flame atomic absorption spectroscopy (FAAS).

  7. 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.

  8. Stable carbon isotopes as indicators for micro-geomorphic changes in palsa peats

    NASA Astrophysics Data System (ADS)

    Alewell, Christine; Giessler, Reiner; Klaminder, Jonathan; Rollog, Mark

    2010-05-01

    Global climate change is significantly threatening stability and functioning of permafrost soils in extended areas of the northern latitudes and / or at high altitudes. A thawing of permafrost soils will most likely result in a positive feedback mechanism due to accelerated degradation of soil organic matter. The latter will not only induce release of substantial amounts of carbon into the atmosphere but also thermokast erosion and thus degradation of these unique systems. As such, biodiversity and functioning of these ecosystems are under immediate threat. One very unique northern ecosystem type are palsa peats, also called palsa mires. Palsa mires are a type of peat land typified by characteristic high mounds (called hummocks), each with a permanently frozen core. The freezing of the underlying horizons uplift these hummocks out of the groundwater saturated zone. Between the hummocks are wet depressions called hollows, which develop where the ground surface is frozen only for part of the year. Palsa mires are common in the former USSR, Canada and parts of Scandinavia and characterized by a unique geochemistry and biodiversity. If these sensitive ecosystems are exposed to environmental change, not only hydrology and vegetation composition but also degradation and mineralisation patterns of soil organic matter will change. The latter should be reflected in stable carbon isotope depth profiles. We investigated the depth distribution of stable carbon isotopes in Palsa mires of northern Sweden (Stordalen and Storflaket near Abisco, Lapland). Our data indicate that stable isotope depth profiles are influenced by environmental change and/ or soil forming processes in space and time. We find a consistent difference between depth profiles of hummocks and hollows. Hollows which are influenced by thermokarst erosion and are thus affected by thawing, breaking and submerging of peat chunks into the hollows, differ in their isotope depth profile from undisturbed hollows. The new supply of hummock peat material in the hollows might increase mineralisation processes in the hollows. From eight investigated hummocks six show a very clear pattern: an increase of d13C isotope profiles up to a certain depth and then a decrease to more lighter values in the deeper horizons. The increase with depth in the upper horizons corresponds to d13C increases with depth of mature, well drained soils where aerobic decomposition favours selective loss of 12C. Interestingly, the increase in ?13C with depth is regardless of the peak depth always around d13C = 3.3 ‰. The deeper horizons of the investigated hummocks follow more the pattern expected in hollows with low degradation rates. The latter might indicate that at a certain point in time the permafrost lifted hollow peat material out of the groundwater level zone. Isotope patterns reflect this change from anaerobic to aerobic degradation. We conclude that the difference in depth profile between hollows in Storflaket and Stordalen might indicate the difference in site disturbance due to climate change or due to the different hydrology of the sites (less groundwater movement in Storflaket compared to Stordalen). The most likely explanation for the turning points is a change in hydrology (likely followed by vegetation changes) due to permafrost uplifting.

  9. A Parameterized Model for Peat Formation and Water Table Dynamics in Tropical Peat Swamp Forests of Brunei Darussalam

    NASA Astrophysics Data System (ADS)

    Cobb, A.; Gandois, L.; Hoyt, A.; Abu Salim, K.; Yussof, M.; Jalil, J.; Ali Ahmad, J.; Su'ut, N.; Harvey, C. F.

    2012-12-01

    In tropical peat swamp forests carbon sequestration and emission are tightly coupled to hydrological processes. Little is know about how these processes operate under natural conditions because few undisturbed peat forests remain. We present a combined groundwater-decomposition model of tropical peat forest parameterized by two years of field measurements from two field sites in Brunei Darussalam. The measurements at these sites, one pristine and one deforested but not drained, include continuous water table, throughfall and rainfall data. The model represents hourly shifts in the water table elevation driven by rainfall, runoff and evaporation and combines these hydrologic components with a representation of the peat surface texture and decay rates of both exposed and saturated peat. By linking these small-scale processes to kilometer scale flow, the model reproduces the growth of large, approximately parabolic peat domes over millennia. We show that nonlinear dynamics in the system lead to a strong dependency of peat formation and decomposition rates on the seasonality of rainfall.

  10. Hillslope Soils and Organic Matter Dynamics within a Native American Agroecosystem on the Colorado Plateau

    E-print Network

    Norton, Jay B.

    Plateau J. B. Norton,* J. A. Sandor, and C. S. White ABSTRACT retention in alluvium-derived soils) create a convincing case forabout soil and hydrological processes that link upland watersheds to alluvium show that head- tivity of soils derived from alluvium, we studied soil-vegetation-land- water streams

  11. Microbial community response to permafrost thaw after wildfire in an Alaskan upland boreal forest

    NASA Astrophysics Data System (ADS)

    Tas, N.; Jorgenson, M. T.; Wang, S.; Berhe, A. A.; Wickland, K. P.; Waldrop, M. P.; Jansson, J. K.

    2012-12-01

    Fire is a major factor controlling the long-term dynamics of soil carbon in Alaskan boreal forests. Wildfire not only contributes to a significant global emission of greenhouse gasses but also can indirectly result in the deepening of the active layer and thawing of near-surface permafrost due to reductions in organic layer depth and increases in heat flux through soil. Although boreal ecosystems are fire-adapted, increased fire frequency and rising global temperatures may result in warmer soils and therefore increase the metabolic rates of decomposer microbes and result in accelerated permafrost decomposition and greenhouse gas fluxes. In addition to fire-mediated changes in soil and vegetation structure, changes in the soil microbial community structure are likely to have consequences for rates of soil carbon cycling. In this study we aimed to define the impact of fire on soil microbial communities in an upland black spruce forest and to assess microbial metabolic potential for soil respiration, methanogenesis, and nitrous oxide (N2O) flux. Soil samples from two fire impacted and three control (unburned) locations were collected near Nome Creek, AK, an upland moderately drained black spruce forest. This location was within the Boundary fire that burned between mid-June and the end of August 2004. Soil temperature measurements from before and after the fire showed that soils were warmer after the fire event and the permafrost thawed below 1m. At each sampling location, soil and permafrost samples were collected every 10 cm to a depth of 1 m. Besides biochemical characterization, CO2, CH4, N2O fluxes and potential activities of enzymes involved in extracellular decomposition of complex organic molecules (hemicellulose, chitin and lignin) were measured. The microbial community composition in the samples was determined by sequencing of 16S rRNA genes and microbial metabolic potential was assessed via sequencing of total genomic DNA (metagenomics) in selected active, transition and permafrost layers. Fire impacted locations were characterized with higher pH, soil moisture, and dissolved organic carbon concentrations compared to control locations. CO2 and CH4 fluxes were lower in burned sites compared to control sites, particularly at the depth of permafrost. In contrast, N2O production was higher in burned soils. All of the enzymes had significantly lower activity in fire affected locations than in controls. There were no major differences in the microbial diversity of active layers between fire impacted and control locations. However, microbial diversity was lower in thawed permafrost layers of the burned samples compared to the controls. At all depths the microbial community composition was significantly different between burned and unburned sites. Metagenome sequencing revealed reduced metabolic capacity in genes for sugar and carbohydrate processing in burned active layer soils, whereas some genes for other processes such as stress response were enriched in thawed permafrost layers. In this ongoing project, microbial communities and processes will be further investigated to determine linkages between genomics, enzyme activities, and greenhouse gas fluxes.

  12. Tropical organic soils ecosystems in relation to regional water resources in southeast Asia

    SciTech Connect

    Armentano, T. V.

    1982-01-01

    Tropical organic soils have functioned as natural sinks for carbon, nitrogen, slfur and other nutrients for the past 4000 years or more. Topographic evolution in peat swamp forests towards greater oligotrophy has concentrated storage of the limited nutrient stock in surface soils and biota. Tropical peat systems thus share common ecosystem characteristics with northern peat bogs and certain tropical oligotrophic forests. Organic matter accumulation and high cation-exchange-capacity limit nutrient exports from undisturbed organic soils, although nutrient retention declines with increasing eutrophy and wetland productivity. Peat swamps are subject to irreversible degradation if severely altered because disturbance of vegetation, surface peats and detritus can disrupt nuttrient cycles and reduce forest recovery capacity. Drainage also greatly increases exports of nitrogen, phosphorus and other nutrients and leads to downstream eutrophication and water quality degradation. Regional planning for clean water supplies must recognize the benefits provided by natural peatlands in balancing water supplies and regulating water chemistry.

  13. 75 FR 70221 - City of Upland Public Works Department; Notice of Application Accepted for Filing, Soliciting...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-17

    ...6688-002] City of Upland Public Works Department; Notice of Application...Protests, Ready for Environmental Analysis, and Soliciting Comments...Applicant: City of Upland Public Works Department. e. Name of Project...Mr. Anthony M. La, Public Works Director, City of Upland...

  14. Development of interspecific hybrids between upland cotton and D-genome diploid species of Gossypium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Upland cotton, G. hirsutum, is a tetraploid (AADD) that has become the predominant cotton species of commerce worldwide. Bottlenecks during speciation and domestication have resulted in limited genetic diversity among upland cotton cultivars. In the summer of 2006 we crossed three upland cotton cu...

  15. Upland Erosion Modeling Pierre Y. Julien, Mark L. Velleux, Un Ji, and Jaehoon Kim

    E-print Network

    Julien, Pierre Y.

    9 Upland Erosion Modeling Pierre Y. Julien, Mark L. Velleux, Un Ji, and Jaehoon Kim CONTENTS UPLAND EROSION PROCESSES WATERSHED MODELING WATERSHED MODEL APPLICATION ACKNOWLEDGEMENTS REFERENCES Abstract Significant advances in upland erosion modeling have been achieved in the past decade. The TREX (Two

  16. Coupling upland watershed and downstream waterbody hydrodynamic and water quality models

    E-print Network

    Coupling upland watershed and downstream waterbody hydrodynamic and water quality models (SWAT analyses of hydrological and water quality processes in the upland watershed and downstream waterbody. We the combined processes of water quantity and quality both in the upland watershed and downstream waterbody

  17. Influence of porewater velocity and ionic strength on DOC concentrations in and losses from peat-sand mixtures

    NASA Astrophysics Data System (ADS)

    Pfaffner, Nora; Tiemeyer, Bärbel; Fiedler, Sabine

    2015-04-01

    Organic soils play an important role in the global carbon cycle as they can act as a source or a sink for greenhouse gas emissions. The new IPCC Wetlands Supplement accounts for the first time for CO2 emissions from the decomposition of dissolved organic carbon (DOC). While there is a wealth of studies on "true" peat soils, knowledge on DOC losses from organic soils heavily disturbed by e.g. mixing with sand is fragmentary. Moreover, there are only a few studies on the influence of soil hydrological properties on DOC transport. This study investigates physico-chemical controls on the concentration and losses of DOC from a peat-sand mixture in a saturated column experiment with undisturbed columns. The soil originates from the study site "Grosses Moor" (Northern Germany) which is a former bog where peat layers remaining after peat mining were mixed with the underlying mineral soil. We studied the influence of the flow regime and the ionic strength of the irrigation solution on DOC concentrations and losses. Three different pumping rates and two different ionic strengths determined by different concentrations of a sodium chloride-calcium chloride mixture in the irrigation solution were applied. Transport properties of the soil were obtained by analyzing breakthrough curves (BTCs) of a conservative tracer (potassium bromide). For interpretation of the BTCs, the transport model STANMOD which is based on the two-region (mobile/immobile) non-equilibrium concept was fitted to the data. The shape of the BTCs and the STANMOD results showed that three of the four columns had a dual porosity structure, which affects the porewater velocity and the contact area. After a large initial peak, DOC concentrations equilibrated to nearly constant values. Increased porewater velocities decreased the concentration of DOC, but increased the losses. A new equilibrium concentration was reached after nearly all changes of the porewater velocity. At maximum pumping rates as determined from field infiltration experiments, no saturation of the losses could be observed. A high ionic strength caused a strong reduction of the pH-value. The combination of these two factors strongly reduced the DOC concentration in the effluent and supported iron flocculation and coagulation. The strong response of the DOC concentrations on the high ionic strength or on the low pH-value suggests that DOC concentrations and losses in these soils are controlled by its coagulation properties, but limited by the actual flow regime and the presence or absence of immobile zones.

  18. Warming-induced reduced peat accrual rates and potential C losses in Northern U.S

    NASA Astrophysics Data System (ADS)

    Fissore, C.; Nater, E. A.; Moskun, A.; Klein, A.; Le, T.

    2013-12-01

    Peatlands located at northern latitudes represent a sink of carbon (C) that is at risk of being lost to the atmosphere if current and expected changes in climate accelerate existing C stock decomposition rates. The extent of such potential loss is still unknown, but recent studies suggest that accrual rate of this critical C stock may be in decline due to more rapid decomposition of plant material reaching the soil. The consequences for our climate system can be significant. If large amounts of C currently ';locked' belowground in peatland ecosystems were to be decomposed and hence lost to the atmosphere, atmospheric concentration of CO2 would increase, causing further warming and hence even more rapid decomposition of peatland C. Our objective in this study is to investigate and compare past and more recent rates of C accrual in peatlands to determine if the rates of C accrual are declining. We collected intact frozen blocks of peat from three sites in Northern Minnesota and sectioned them into horizontal slices, which are being dated by 137Cs and 14C. Atmospheric concentrations of both 137Cs and 14C spiked in the 1960's due to nuclear bomb testing, leaving a ';signature' in organic matter (14C) and sediments (137Cs). The signal has steadily declined since that time. Detection of the signal in current soil samples will allow us to date the sample and consequently to measure the quantity of C accrued in the peat over various measured time intervals.

  19. 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).

  20. 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.

  1. Influence of water table changes on peat features and humification processes

    NASA Astrophysics Data System (ADS)

    Zaccone, Claudio; Miano, Teodoro M.

    2010-05-01

    Peatland ecosystems play an important role in the carbon cycle. In their natural state, they have been shown to be net sinks for atmospheric carbon dioxide (CO2) and net sources of greenhouse gases on a long term basis. Peatlands could provide a significant positive feedback for climate change. Unfortunately, drainage of peatlands for forestry, agriculture and/or peat extraction for energy is a common practice in several countries (e.g., the Fenno-Scandinavian region, Canada and Russia). When they are drained, peatland areas become a threat to the environment as the thickness of the aerobic layer increases. This leads to an increase in the rate of organic matter (OM) decomposition and, as a result, peatlands might change from a net carbon sink to a large carbon source, thus resulting in an increase of CO2 and methane (CH4) emissions from these organic soils. In order to better understand hydrological, physical and chemical changes occurring as result of water table level changes, we studied the OM evolution of bulk peat and its humified fraction in undisturbed condition. A 81 cm peat core was collected from Etang de la Gruère, a Swiss ombrotrophic bog in the Jura Mountains, and humic acids (HA) isolated. Both bulk peat and HA samples were characterized using several molecular spectroscopic methods (Ft-IR, UV-Vis, DSC, Fluorescence) and elemental analysis (CHNS-O). In general, Ft-IR, UV-Vis and fluorescence results suggest significant variations of the molecular composition and chemical structures of the peat samples along the profile. In detail, the superficial zone (from the living layer to approximately 24 cm) is characterized by oxidative processes and decomposition phenomena of plant tissues and residues continuously occurring in the top horizons of the peat, leading to the release of variable amounts of organic acids and small molecular mass compounds. This section is poorly decomposed. The HA fraction accounts for 6.6 to 15.4% of the bulk peat, thus meaning that only ca. 7.8-17.3% (13.9%, average value) of total C present in peat is stored in the recalcitrant and stable HA fraction, and thus most of the C stock can be easily mineralized. On the opposite, the bottom zone (under 39 cm depth), in which molecules with high molar mass and high degree of condensation are observed, seems more homogeneous and reflects a peat zone apparently characterized by uniform and permanent anoxic conditions. Here, an obligate anaerobic microbial community can carry out only a partial and slow decomposition of the OM. In this section of the profile, the HA fraction accounts for ca. 20.0-32.7% of the bulk peat, representing ca. 25.1-37.1% (28.6%, average value) of total C present in peat is stored in the HA fraction. But the variability in the depth of the water table level, providing temporary oxygen diffusion even at greater depth, originated also a "transitional" zone, from about 24-39 cm. Here, changes between aerobic and anaerobic conditions activated microbially induced humification and transformation processes of polysaccharidic and lignin-derived residues, as well as very complex interactions between organic and inorganic compounds. This section, in fact, was characterized by the highest ash content (4.9%, average value) and, if compared with the deeper layer and part of the upper one, by the occurrence of less humified molecules. In this part of the profile, the HA fraction represents ca. 24.3% (average value) of total C present in bulk peat. In conclusion, and always considering that this study is just a photo of a particular moment, our data suggested that, although a relevant portion of C is stored into the HA fraction, the fluctuations of the water table could favour the temporal exposition of these macromolecules to the microbial activity, thus transforming a stable C pool into a labile one.

  2. Environmental effects of dredging: Upland animal bioassays of dredged materials. Technical note

    SciTech Connect

    Simmers, J.W.; Rhett, R.G.; Lee, C.R.

    1986-01-01

    The Clean Water Act in the United States requires that the environmental evaluation of dredged material prior to discharge or impacting the waters of the United States include the effects of disposal on concentrations of contaminants through biological processes. This results in a need for Corps of Engineers districts to be able to predict the contamination of animals that may be associated with potential disposal alternatives: open-water disposal, upland disposal, and wetland creation. The following is a summary of the results of bioassay procedures using the earthworm Eisenia foetida to evaluate the potential contaminant mobility into soil-dwelling animals. These tests were derived from proposed Organization for European Common Development (OECD) and European Economics Commission (EEC) test procedures (evaluating the effects of new chemicals) and modified to consider accumulation and sublethal effects rather than toxicity.

  3. 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

  4. 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

  5. The Role of Social Constructions and Biophysical Attributes of the Environment in Decision-Making in the Context of Biofuels and Rubber Production Partnership Regimes in Upland Philippines

    NASA Astrophysics Data System (ADS)

    Montefrio, M. F.

    2012-12-01

    Burgeoning attention in biofuels and natural rubber has spurred interest among governments and private companies in integrating marginalized communities into global commodity markets. Upland farmers from diverse cultural backgrounds and biophysical settings today are deciding whether to agree with partnership proposals from governments and private firms to grow biofuels and natural rubber. In this paper, I examine whether upland farmers' socio-environmental constructions (evaluative beliefs, place satisfaction, and ecological worldviews) and the actual biophysical attributes (land cover and soil types) of upland environments, respectively, function as significant predictors of the intent and decisions of indigenous and non-indigenous farmers to cooperate with government and private actors to establish certain biofuel crops and natural rubber production systems in Palawan, Philippines. Drawing from ethnography and statistical analysis of household surveys, I propose that social constructions and the biophysical attributes of the environment are closely related with each other and in turn both influence individual decision-making behavior in resource-based production partnership regimes. This has significant implications on the resilience of socio-ecological systems, particularly agro-ecosystems, as certain upland farmers prefer to engage in intensive, monocrop production of biofuels and natural rubber on relatively more biodiverse areas, such as secondary forests and traditional shifting cultivation lands. The study aims to advance new institutional theories of resource management, particularly Ostrom's Institutional Analysis and Development and Socio-Ecological Systems frameworks, and scholarship on environmental decision-making in the context of collective action.

  6. Interactive effects of vegetation, soil moisture and bulk density on depth of burning of thick organic soils

    E-print Network

    Turetsky, Merritt

    Interactive effects of vegetation, soil moisture and bulk density on depth of burning of thick consumption. We experimentally altered soil moisture profiles of peat monoliths collected from several (Johnstone and Chapin 2006; Benscoter and Vitt 2008; Johnstone et al. 2010), soil moisture and temperature

  7. Interactive effects of vegetation, soil moisture and bulk density on depth of burning of thick organic soils

    E-print Network

    Benscoter, Brian W.

    PROOF ONLY Interactive effects of vegetation, soil moisture and bulk density on depth of burning consumption. We experimentally altered soil moisture profiles of peat monoliths collected from several (Johnstone and Chapin 2006; Benscoter and Vitt 2008; Johnstone et al. 2010), soil moisture and temperature

  8. Impact of Water Level on Carbon Sequestration at a Sub-tropical Peat Marsh

    NASA Astrophysics Data System (ADS)

    Sumner, D.; Hinkle, C.; Graham, S.; Li, J.

    2013-12-01

    The impact of water level on sub-tropical peat marsh atmospheric/landscape carbon exchange was explored through eddy-covariance measurement of carbon dioxide and methane fluxes over a site at Blue Cypress Conservation Area in Florida. This site is vegetated with tall, dense sawgrass (Cladium jamaicense) and a thick accumulation of peat (over 3 m) suggesting a historically high primary productivity and carbon sequestration. Water managers are particularly interested in understanding how water-level controls can be directed to maintain topography through avoidance of excessive drought-induced oxidative losses of peat soil, as well as to minimize releases of greenhouse gases to the atmosphere. Comparison of net ecosystem productivity (NEP) during a wet year of continuous inundation and a drier year with a 9-month hydroperiod (NEP of 710 and 180 g C/m2/yr, respectively) suggests the positive impact of inundation on sequestration of carbon dioxide. These results are counter to previous research in short stature (1 m or less) sawgrass marshes in the Florida Everglades which indicate suppression of productivity during inundation. This seeming contradiction is probably best explained by the tall stature (over 2 m) of sawgrass at the study site in which inundation still does not cover a substantial fraction of the green leaves and the lower canopy is largely composed of brown and decaying leaves. Gross ecosystem productivity (GEP) was suppressed during the dry year (GEP = 1380 and 1030 g C/m2/yr for wet and dry years, respectively), probably as a consequence of canopy moisture stress. Respiration (R) was enhanced the year when water levels were farthest below land surface (R = 670 and 850 g C/m2/yr for wet and dry years, respectively) as a result of soil oxidation. GEP remained suppressed during the dry year even after re-flooding, probably because of relatively low photosynthetic leaf area that was the legacy of reduced canopy growth rates during the drought. Over a seven-month measurement period spanning a dry-to-inundated transition in the marsh, methane flux was negligible during non-inundated periods, but was substantial (averaging 80 g C/m2/yr) during wet periods. The results of this study suggest that water level is a critical control on atmospheric carbon exchanges at this peat marsh with implications for water management and strategic planning under potentially drier conditions that might occur in response to climate change.

  9. Impact of Water Level on Carbon Sequestration at a Sub-tropical Peat Marsh

    NASA Astrophysics Data System (ADS)

    Sumner, D.; Hinkle, C.; Li, J.

    2012-12-01

    The impact of water level on sub-tropical peat marsh atmospheric/landscape carbon exchange was explored through eddy-covariance measurement of carbon dioxide and methane fluxes over a site at Blue Cypress Conservation Area in Florida. This site is vegetated with tall, dense sawgrass (Cladium jamaicense) and a thick accumulation of peat (over 3 m) suggesting a historically high primary productivity and carbon sequestration. Water managers are particularly interested in understanding how water-level controls can be directed to maintain topography through avoidance of excessive drought-induced oxidative losses of peat soil, as well as to minimize releases of greenhouse gases to the atmosphere. Comparison of net ecosystem productivity (NEP) during a wet year of continuous inundation and a drier year with a 9-month hydroperiod (NEP of 710 and 180 g C/m2/yr, respectively) suggests the positive impact of inundation on sequestration of carbon dioxide. These results are counter to previous research in short stature (1 m or less) sawgrass marshes in the Florida Everglades which indicate suppression of productivity during inundation. This seeming contradiction is probably best explained by the tall stature (over 2 m) of sawgrass at the study site in which inundation still does not cover a substantial fraction of the green leaves and the lower canopy is largely composed of brown and decaying leaves. Gross ecosystem productivity (GEP) was suppressed during the dry year (GEP = 1380 and 1030 g C/m2/yr for wet and dry years, respectively), probably as a consequence of canopy moisture stress. Respiration (R) was enhanced the year when water levels were farthest below land surface (R = 670 and 850 g C/m2/yr for wet and dry years, respectively) as a result of soil oxidation. GEP remained suppressed during the dry year even after re-flooding, probably because of relatively low photosynthetic leaf area that was the legacy of reduced canopy growth rates during the drought. Over a seven-month measurement period spanning a dry-to-inundated transition in the marsh, methane flux was negligible during non-inundated periods, but was substantial (averaging 80 g C/m2/yr) during wet periods. The results of this study suggest that water level is a critical control on atmospheric carbon exchanges at this peat marsh with implications for water management and strategic planning under potentially drier conditions that might occur in response to climate change.

  10. Analyses of Fusarium wilt race 3 resistance in Upland cotton (Gossypium hirsutum L.).

    PubMed

    Abdullaev, Alisher A; Salakhutdinov, Ilkhom B; Egamberdiev, Sharof Sh; Kuryazov, Zarif; Glukhova, Ludmila A; Adilova, Azoda T; Rizaeva, Sofiya M; Ulloa, Mauricio; Abdurakhmonov, Ibrokhim Y

    2015-06-01

    Fusarium wilt [Fusarium oxysporum f.sp. vasinfectum (FOV) Atk. Sny & Hans] represents a serious threat to cotton (Gossypium spp.) production. For the last few decades, the FOV pathogen has become a significant problem in Uzbekistan causing severe wilt disease and yield losses of G. hirsutum L. cultivars. We present the first genetic analyses of FOV race 3 resistance on Uzbek Cotton Germplasm with a series of field and greenhouse artificial inoculation-evaluations and inheritance studies. The field experiments were conducted in two different sites: the experimental station in Zangiota region-Environment (Env) 1 and the Institute of Cotton Breeding (Env-2, Tashkent province). The Env-1 was known to be free of FOV while the Env-2 was known to be a heavily FOV infested soil. In both (Env-1 and Env-2) of these sites, field soil was inoculated with FOV race 3. F2 and an F3 Upland populations ("Mebane B1" × "11970") were observed with a large phenotypic variance for plant survival and FOV disease severity within populations and among control or check Upland accessions. Wilt symptoms among studied F2 individuals and F3 families significantly differed depending on test type and evaluation site. Distribution of Mendelian rations of susceptible (S) and resistant (R) phenotypes were 1S:1R field Env-1 and 3S:1R field Env-2 in the F2 population, and 1S:3R greenhouse site in the F3 population. The different segregation distribution of the Uzbek populations may be explained by differences in FOV inoculum level and environmental conditions during assays. However, genetic analysis indicated a recessive single gene action under high inoculum levels or disease pressure for FOV race 3 resistance. Uzbek germplasm may be more susceptible than expected to FOV race 3, and sources of resistance to FOV may be limited under the FOV inoculum levels present in highly-infested fields making the breeding process more complex. PMID:25896369

  11. Whole-island carbon stocks in the tropical Pacific: implications for mangrove conservation and upland restoration.

    PubMed

    Donato, D C; Kauffman, J B; Mackenzie, R A; Ainsworth, A; Pfleeger, A Z

    2012-04-30

    Management of forest carbon (C) stocks is an increasingly prominent land-use issue. Knowledge of carbon storage in tropical forests is improving, but regional variations are still poorly understood, and this constrains forest management and conservation efforts associated with carbon valuation mechanisms (e.g., carbon markets). This deficiency is especially pronounced in tropical islands and low-lying coastal areas where climate change impacts are expected to be among the most severe. This study presents the first field estimate of island-wide carbon storage in ecosystems of Oceania, with special attention to the regional role of coastal mangroves, which occur on islands and coastal zones throughout the tropics. On two island groups of Micronesia (Yap and Palau), we sampled all above- and belowground C pools, including soil and vegetation, in 24 sites distributed evenly among the three major vegetation structural types: mangroves, upland forests, and open savannas (generally on degraded lands formerly forested). Total C stocks were estimated to be 3.9 and 15.2 Tg C on Yap and Palau, respectively. Mangroves contained by far the largest per-hectare C pools (830-1218 Mg C ha(-1)), with deep organic-rich soils alone storing more C (631-754 Mg C ha(-1)) than all pools combined in upland systems. Despite covering just 12-13% of land area, mangroves accounted for 24-34% of total island C stocks. Savannas (156-203 Mg C ha(-1)) contained significantly lower C stocks than upland forests (375-437 Mg C ha(-1)), suggesting that reforesting savannas where appropriate has high potential for carbon-based funding to aid restoration objectives. For mangroves, these results demonstrate the key role of these systems within the broader context of C storage in island and coastal landscapes. Sustainable management of mangrove forests and their large C stocks is of high importance at the regional scale, and climate change mitigation programs such as REDD+ could play a large role in avoiding deforestation of mangroves where this is a management objective. PMID:22325586

  12. A multi-scale modelling procedure to quantify hydrological impacts of upland land management

    NASA Astrophysics Data System (ADS)

    Wheater, H. S.; Jackson, B.; Bulygina, N.; Ballard, C.; McIntyre, N.; Marshall, M.; Frogbrook, Z.; Solloway, I.; Reynolds, B.

    2008-12-01

    Recent UK floods have focused attention on the effects of agricultural intensification on flood risk. However, quantification of these effects raises important methodological issues. Catchment-scale data have proved inadequate to support analysis of impacts of land management change, due to climate variability, uncertainty in input and output data, spatial heterogeneity in land use and lack of data to quantify historical changes in management practices. Manipulation experiments to quantify the impacts of land management change have necessarily been limited and small scale, and in the UK mainly focused on the lowlands and arable agriculture. There is a need to develop methods to extrapolate from small scale observations to predict catchment-scale response, and to quantify impacts for upland areas. With assistance from a cooperative of Welsh farmers, a multi-scale experimental programme has been established at Pontbren, in mid-Wales, an area of intensive sheep production. The data have been used to support development of a multi-scale modelling methodology to assess impacts of agricultural intensification and the potential for mitigation of flood risk through land use management. Data are available from replicated experimental plots under different land management treatments, from instrumented field and hillslope sites, including tree shelter belts, and from first and second order catchments. Measurements include climate variables, soil water states and hydraulic properties at multiple depths and locations, tree interception, overland flow and drainflow, groundwater levels, and streamflow from multiple locations. Fine resolution physics-based models have been developed to represent soil and runoff processes, conditioned using experimental data. The detailed models are used to calibrate simpler 'meta- models' to represent individual hydrological elements, which are then combined in a semi-distributed catchment-scale model. The methodology is illustrated using field and catchment-scale simulations to demonstrate the the response of improved and unimproved grassland, and the potential effects of land management interventions, including farm ponds, tree shelter belts and buffer strips. It is concluded that the methodology developed has the potential to represent and quantify catchment-scale effects of upland management; continuing research is extending the work to a wider range of upland environments and land use types, with the aim of providing generic simulation tools that can be used to provide strategic policy guidance.

  13. The effects of fire on the thermal stability of permafrost in lowland and upland black spruce forests of interior Alaska in a changing climate

    NASA Astrophysics Data System (ADS)

    Jafarov, E. E.; Romanovsky, V. E.; Genet, H.; McGuire, A. D.; Marchenko, S. S.

    2013-09-01

    Fire is an important factor controlling the composition and thickness of the organic layer in the black spruce forest ecosystems of interior Alaska. Fire that burns the organic layer can trigger dramatic changes in the underlying permafrost, leading to accelerated ground thawing within a relatively short time. In this study, we addressed the following questions. (1) Which factors determine post-fire ground temperature dynamics in lowland and upland black spruce forests? (2) What levels of burn severity will cause irreversible permafrost degradation in these ecosystems? We evaluated these questions in a transient modeling-sensitivity analysis framework to assess the sensitivity of permafrost to climate, burn severity, soil organic layer thickness, and soil moisture content in lowland (with thick organic layers, ˜80 cm) and upland (with thin organic layers, ˜30 cm) black spruce ecosystems. The results indicate that climate warming accompanied by fire disturbance could significantly accelerate permafrost degradation. In upland black spruce forest, permafrost could completely degrade in an 18 m soil column within 120 years of a severe fire in an unchanging climate. In contrast, in a lowland black spruce forest, permafrost is more resilient to disturbance and can persist under a combination of moderate burn severity and climate warming.

  14. Effects of fire on the thermal stability of permafrost in lowland and upland black spruce forests of interior Alaska in a changing climate

    USGS Publications Warehouse

    Jafarov, Elchin E.; Romanovsky, Vladimir E.; Genet, Helene; McGuire, Anthony David; Marchenko, Sergey S.

    2013-01-01

    Fire is an important factor controlling the composition and thickness of the organic layer in the black spruce forest ecosystems of interior Alaska. Fire that burns the organic layer can trigger dramatic changes in the underlying permafrost, leading to accelerated ground thawing within a relatively short time. In this study, we addressed the following questions. (1) Which factors determine post-fire ground temperature dynamics in lowland and upland black spruce forests? (2) What levels of burn severity will cause irreversible permafrost degradation in these ecosystems? We evaluated these questions in a transient modeling–sensitivity analysis framework to assess the sensitivity of permafrost to climate, burn severity, soil organic layer thickness, and soil moisture content in lowland (with thick organic layers, ~80 cm) and upland (with thin organic layers, ~30 cm) black spruce ecosystems. The results indicate that climate warming accompanied by fire disturbance could significantly accelerate permafrost degradation. In upland black spruce forest, permafrost could completely degrade in an 18 m soil column within 120 years of a severe fire in an unchanging climate. In contrast, in a lowland black spruce forest, permafrost is more resilient to disturbance and can persist under a combination of moderate burn severity and climate warming.

  15. A Database and Synthesis of Northern Peatland Soil Properties and Holocene Carbon and Nitrogen Accumulation

    NASA Technical Reports Server (NTRS)

    Loisel, Julie; Yu, Zicheng; Beilman, David W.; Camill, Philip; Alm, Jukka; Amesbury, Matthew J.; Anderson, David; Andersson, Sofia; Bochicchio, Christopher; Barber, Keith; Belyea, Lisa R.; Bunbury, Joan; Chambers, Frank M.; Charman, Daniel J.; De Vleeschouwer, Francois; Fialkiewicz-Koziel, Barbara; Finkelstein, Sarah A.; Galka, Mariusz; Garneau, Michelle; Hammarlund, Dan; Hinchcliffe, William; Holmquist, James; Hughes, Paul; Jones, Miriam C.; Klein, Eric S.; Kokfelt, Ulla; Korhola, Atte; Kuhry, Peter; Lamarre, Alexandre; Lamentowicz, Mariusz; Large, David; Lavoie, Martin; McDonald, Glen; Magnan, Gabriel; Peteet, Dorothy

    2014-01-01

    Here, we present results from the most comprehensive compilation of Holocene peat soil properties with associated carbon and nitrogen accumulation rates for northern peatlands. Our database consists of 268 peat cores from 215 sites located north of 45 deg N. It encompasses regions within which peat carbon data have only recently become available, such as the West Siberia Lowlands, the Hudson Bay Lowlands, Kamchatka in Far East Russia, and the Tibetan Plateau. For all northern peatlands, carbon content in organic matter was estimated at 42 +/- 3% (standard deviation) for Sphagnum peat, 51 +/- 2% for non-Sphagnum peat, and at 49 +/- 2% overall. Dry bulk density averaged 0.12 +/- 0.07 g/cu cm, organic matter bulk density averaged 0.11 +/- 0.05 g/cu cm, and total carbon content in peat averaged 47 +/- 6%. In general, large differences were found between Sphagnum and non-Sphagnum peat types in terms of peat properties. Time-weighted peat carbon accumulation rates averaged 23 +/- 2 (standard error of mean) g C/sq m/yr during the Holocene on the basis of 151 peat cores from 127 sites, with the highest rates of carbon accumulation (25-28 g C/sq m/yr) recorded during the early Holocene when the climate was warmer than the present. Furthermore, we estimate the northern peatland carbon and nitrogen pools at 436 and 10 gigatons, respectively. The database is publicly available at https://peatlands.lehigh.edu.

  16. INTERSPECIFIC CHROMOSOME SUBSTITUTION LINES IN UPLAND COTTON IMPROVEMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite the economic importance of Upland cotton, the genetic base of US cultivars and elite germplasm is very narrow. Two of the primary impediments to genetic improvement of cotton are: 1) insufficient information about genes that control important traits and 2) under-utilization of diverse ger...

  17. SUSCEPTIBILITY OF UPLAND COTTON CULTIVARS TO INFESTATION BY SILVERLEAF WHITEFLY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sixteen upland cotton, Gossypium hirsutum L., cultivars and experimental breeding-lines were evaluated in the field for susceptibility to silverleaf whitefly, Bemisia argentifolii Bellows and Perring, sown at the UC Desert Research & Extension Center, Imperial Valley, CA, into plots of a randomized ...

  18. Upland fiber changes due to ginning and lint cleaning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was done to determine how upland cotton fiber length distribution was affected during ginning and how possible length changes might affect subsequent textile processing. The full range of ginning treatments currently commercially available in the U. S. cotton industry were utilized. These ...

  19. Imazamox Tolerance in Mutation Derived Lines of Upland Cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Induction of genes conferring herbicide resistance by mutagenesis could facilitate use of imidazolinone herbicides in upland cotton (Gossypium hirsutum L.). In 1997 and 1998, seeds of eight High Plains cotton cultivars were treated with 2.45% v/v EMS (ethyl methane sulfonate). The resulting M3 and M...

  20. Natural hybrids and gene flow between upland and lowland switchgrass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Switchgrass (Panicum virgatum L.) is a perennial grass native to the North American tallgrass prairie and savanna habitats and is broadly adapted to the central and eastern USA. Upland and lowland ecotypes represent the two major taxa within switchgrass, which have distinct, but overlapping distribu...

  1. Development of Reniform Nematode Resistance in Upland Cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this review is to assess development of resistance to the reniform nematode (Rotylenchulus reniformis) in Upland Cotton (Gossypium hirsutum). Cotton cultivars with reniform nematode resistance are needed. The development of resistant cultivars appears possible but presents a signifi...

  2. 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 organic matter along all PD profile. In our opinion, it is explained by rearrangement of qualitative and quantitative composition of microbic biota in consequence of alternate anoxic-oxic conditions creation along all PD of investigated eutrophic bog located in the dingle of ancient flow. Keywords: peat deposits, eutrophic bog, Siberia, microbiological processes, change of organic matter. Acknowledgements: This research was supported by RFFR (No.No. 09-05-00235, 09-05-99007), Minister of education and science (No. 02.740.11.0325).

  3. Intensive flux measurements and analysis of greenhouse gases from an upland cabbage field at Kunsan, Korea

    NASA Astrophysics Data System (ADS)

    Kim, D.; Na, U.

    2010-12-01

    It has been recognized that intensively managed agricultural soil is a dominant source of atmospheric N2O through increase in use of nitrogen fertilizer and soil microbial processes, contributing to about 57% (9Tg y-1) of total N2O annual global emission. Organic carbons in soil and wetland sediment including tidal flat affect the CO2 and CH4 emission in such environments depending on their physicochemical conditions. From October 2009 to June 2010, CO2, CH4, and N2O (GHG) soil emission measurements were conducted from upland cabbage field at Kunsan (35o56’23’’N, 126o43’14’’E), Korea by using closed static chamber method. During the experimental period, hourly GHG emissions were conducted mostly from 1000 to 1800LST in each field measurement day (total 28 days). After placing each chamber over soil surface of two neighboring plots, 50 ml of air sample inside the chambers was taken for every 15 min over a 30 min period by using plastic syringes (total of three samples). GHG concentrations were simultaneously analyzed in the laboratory by using a GC equipped with a methanizer, FID and ECD (Varian CP3800). The GHG fluxes were calculated from a linear regression of the changes in the concentrations. Negative values indicate GHG uptake by the soil surface, and positive values indicate GHG emission to the atmosphere. In addition, soil parameters (e.g. soil moisture, temperature, pH, organic C, soil N) were measured at the sampling plot. The average soil pH and soil moisture during the experimental period was ~pH5.4±0.4 and 70.0±19.7 %WFPS, respectively. The average fluxes and ranges of GHG during the experimental period were -0.004±0.032 mg-m-2 hr-1 (-0.087 ~ 0.045 mg-m-2 hr-1) for CH4, 5.32±57.63 mg-m-2 hr-1 (-92.96 ~ 139.38 mg-m-2 hr-1) for CO2, and 1.119±1.918 mg-m-2 hr-1 (0.077 ~ 8.409 mg-m-2 hr-1) for N2O, respectively. Monthly base flux measurement results revealed that monthly means of CO2 and CH4 flux during October (fall) was positive and significantly higher than those (negative value) during January (winter) when sub soil have low temperature and relatively high moisture due to snow during the winter measurement period. Averages of soil temperature and moisture during these months were 17.5±1.2oC, 45.7±8.2%WFPS for October; and 1.4±1.3oC, 89.9±8.8%WFPS for January. It may indicate that soil temperature and moisture have significant role in determining whether the CO2 and CH4 emission or uptake take place. Low temperature and high moisture above a certain optimum level during winter could weaken microbial activity and the gas diffusion in soil matrix, and then make soil GHG emission to the atmosphere decrease. Other soil parameters were also correlated with GHG emissions and discussed. Both positive and negative gas fluxes in CH4 and CO2 were observed during these measurements, but not for N2O. CH4 and CO2 gases seem to be emitted from soil surface or up taken by the soil depending on other factors such as background concentrations and physicochemical soil conditions. However, still there are many uncertainties and large scarcities in both their determination methods and soil GHG flux data. Improvement of measurement techniques and well-understanding of relationships between gas emission and controlling factors in such environments need to be required.

  4. Modeling the Impact of Forest and Peat Fires on Carbon-Isotopic Compositions of Cretaceous Atmosphere and Vegetation

    NASA Astrophysics Data System (ADS)

    Finkelstein, D. B.; Pratt, L. M.

    2004-12-01

    Prevalence of wildfires or peat fires associated with seasonally dry conditions in the Cretaceous is supported by recent studies documenting the widespread presence of pyrolytic polycyclic aromatic hydrocarbons and fusinite. Potential roles of CO2 emissions from fire have been overlooked in many discussions of Cretaceous carbon-isotope excursions (excluding K-P boundary discussions). Enhanced atmospheric CO2 levels could increase fire frequency through elevated lightning activity. When biomass or peat is combusted, emissions of CO2 are more negative than atmospheric CO2. Five reservoirs (atmosphere, vegetation, soil, and shallow and deep oceans), and five fluxes (productivity, respiration, litter fall, atmosphere-ocean exchange, and surface-deep ocean exchange) were modeled as a closed system. The size of the Cretaceous peat reservoir was estimated by compilation of published early Cretaceous coal resources. Initial pCO2 was assumed to be 2x pre-industrial atmospheric levels (P.A.L.). Critical variables in the model are burning efficiency and post-fire growth rates. Assuming 1% of standing terrestrial biomass is consumed by wildfires each year for ten years (without combustion of peat), an increase of atmospheric CO2 (from 2.0 to 2.2x P.A.L.) and a negative carbon isotope excursion (-1.2 ‰ ) are recorded by both atmosphere and new growth. Net primary productivity linked to the residence time of the vegetation and soil reservoirs results in a negative isotope shift followed by a broad positive isotope excursion. Decreasing the rate of re-growth dampens this trailing positive shift and increases the duration of the excursion. Post-fire pCO2 and new growth returned to initial values after 72 years. Both negative and positive isotope excursions are recorded in the model in surface ocean waters. Exchange of CO2 with the surface- and deep-ocean dampens the isotopic shift of the atmosphere. Excursions are first recorded in the atmosphere (and new growth), followed by the ocean, vegetation, and soil reservoirs. Ten to twenty five-year cycles of drought and fire are not recorded as individual excursions in the soil reservoir as the rate of transfer between the vegetation and soil reservoirs homogenizes the signal. A wildfire-modeled excursion does not propagate a geologically significant excursion through time. Combustion of a peat reservoir is necessary to drive and validate a geologically and isotopically significant excursion. Assuming 0.5% of the standing early Cretaceous peat reservoir is consumed by fire for each year for ten years coupled with the earlier scenario, the atmospheric CO2 increases from 2.0 to 3.1x P.A.L., atmosphere, vegetation, and the surface ocean record a negative carbon isotope excursion of -5.1 ‰ , -3.8 ‰ and -1.8 ‰ respectively, with a duration of 741 years. Increasing the size of the vegetation reservoir translates the excursions from the centennial to millennial scale. For example, doubling the vegetation reservoir (from 1.4 to 2.8E+16 gC) for a 25 year global peat conflagration (0.5% combusted each year) results in a CO2 increase from 2.0 to 4.0x P.A.L., and the atmosphere, vegetation, and the surface ocean reservoirs with a negative carbon isotope excursion of -5.7 ‰ , -8.7 ‰ and -2.3 ‰ respectively. Addition of carbonaceous aerosols (black carbon and polycyclic aromatic hydrocarbons) to pelagic marine sediments could potentially serve as a high-resolution record of ancient fires and firmly tie isotopic shifts to paleofires.

  5. Characteristics of peat deposits in Mississippi River delta plain

    SciTech Connect

    Kosters, E.C.; Bailey, A.

    1983-09-01

    Variations in organic-rich sediment (peat) from the Mississippi River delta plain can be explained by differences in three interrelated parameters: (a) depositional setting, (b) balance between subsidence and detrital influx, and (c) marine inundation. Variations are observed in geomterty of the overall deposits, organic matter content, and the mineralogy of peats and related ashes. Using a vibracorer, samples were collected from two brackish areas (Avery Island/Sale-Cypremort and Barataria basin) and one freshwater area (Gueydan). Peats in all areas average 90% moisture content. Dried peat averages 81.3% organic matter with a bulk density of 0.12 g/cm/sup 3/. Holocene differential compaction has been minimal (< 4%). Conventional ash values indicate different distribution of organic materials for the two brackish areas. For the area containing interdistributary peats, approximately 5% of the subsurface contains more than 70% organic matter, whereas for blanket peats, 14% of the section has more than 70% organic matter. Mineralogic data collected on low-temperature ashes indicate that major minerals in brackish peat consist of kaolinite, quartz, and water-soluble salts, whereas minerals from freshwater samples are primarily kaolinite and quartz. X-ray diffraction and electron microscopy show the presence of smectite, illite, abundant siliceous spicules, framboidal pyrite, biotite, pyroxene, and rutile in the insoluble fraction. Superficial examination of data generated so far suggests that only thin coal seams with high ash would be produced. However, the presence of decomposing siliceous sponge spicules in the ash and the possiblity of ash being leached by fresh ground water, suggest that much ash may be lost during early diagenesis.

  6. Soil structure, colloids, and chemical transport as affected by short-term reducing conditions: a laboratory study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Upland soils in the Midwestern US often undergo reducing conditions when soils are temporally flooded during the spring and remain water saturated for days or weeks. Short-term reducing conditions change the chemistry of the soil and may affect soil structure and solution chemical transport. The eff...

  7. Adaptation to flooding in upland and lowland ecotypes of Cyperus rotundus, a troublesome sedge weed of rice: tuber morphology and carbohydrate metabolism

    PubMed Central

    Peña-Fronteras, Jennifer T.; Villalobos, Mizpah C.; Baltazar, Aurora M.; Merca, Florinia E.; Ismail, Abdelbagi M.; Johnson, David E.

    2009-01-01

    Background and aims In recent years, Cyperus rotundus has become a problem weed in lowland rice (Oryza sativa) grown in rotation with vegetables in the Philippines. As the growth of C. rotundus is commonly suppressed by prolonged flooding, the ability of the weed to grow vigorously in flooded as well as upland conditions suggests that adapted ecotypes occur in these rotations. Studies were conducted to elucidate the mechanisms that permit C. rotundus to tolerate flooded soil conditions. Methods Upland and lowland ecotypes of C. rotundus were compared in terms of growth habit, carbohydrate reserves and metabolism, and activities of enzymes involved in alcoholic fermentation – alcohol dehydrogenase (ADH) and pyruvate decarboxylase (PDC). Key Results The lowland ecotype has much larger tubers than the upland ecotype. Prior to germination, the amylase activity and total non-structural carbohydrate content in the form of soluble sugars were greater in the tubers of lowland plants than in those of upland C. rotundus. At 24 h after germination in hypoxic conditions, PDC and ADH activities in the lowland plants increased, before decreasing at 48 h following germination. In contrast, ADH and PDC activities in the upland plants increased from 24 to 48 h after germination. Conclusions Tolerance of lowland C. rotundus of flooding may be attributed to large carbohydrate content and amylase activity, and the ability to maintain high levels of soluble sugars in the tubers during germination and early growth. This is coupled with the modulation of ADH and PDC activities during germination, possibly to control the use of carbohydrate reserves and sustain substrate supply in order to avoid starvation and death of seedlings with prolonged flooding. PMID:18515404

  8. 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 time for water in any peat bed system that is proposed for the H-12 Outfall. A scope to design and install a pilot level study at H-12 is currently under development. This study will be designed to examine some of the engineering issues that are of concern regarding the scaling of an actual peat bed to treat the volumes of water that are typically discharged through the H-12 Outfall. Different hydraulic paths and configurations are expected to be part of that scope.

  9. 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.

  10. Fate of Fertilizer Nitrogen in a Flooded Rice Soil1 W. H. PATRICK,,JR., AND K. R. REDDY"

    E-print Network

    Florida, University of

    of fertilizer N utilization by rice available on the amount of fertilizer N remaining in the soil (Oryza saliva after planting), several saliva L.) compared to many upland crops (Mitsui, subplots (each 2.32m2 ) were

  11. 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.

  12. 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

  13. A genomic perspective on the important genetic mechanisms of upland adaptation of rice

    PubMed Central

    2014-01-01

    Background Cultivated rice consists of two important ecotypes, upland and irrigated, that have respectively adapted to either dry land or irrigated cultivation. Upland rice, widely adopted in rainfed upland areas in virtue of its little water requirement, contains abundant untapped genetic resources, such as genes for drought adaptation. With water shortage exacerbated and population expanding, the need for breeding crop varieties with drought adaptation becomes more and more urgent. However, a previous oversight in upland rice research reveals little information regarding its genetic mechanisms for upland adaption, greatly hindering progress in harnessing its genetic resources for breeding and cultivation. Results In this study, we selected 84 upland and 82 irrigated accessions from all over the world, phenotyped them under both irrigated and dry land environments, and investigated the phylogenetic relations and population structure of the upland ecotype using whole genome variation data. Further comparative analysis yields a list of differentiated genes that may account for the phenotypic and physiological differences between upland and irrigated rice. Conclusions This study represents the first genomic investigation in a large sample of upland rice, providing valuable gene list for understanding upland rice adaptation, especially drought-related adaptation, and its subsequent utilization in modern agriculture. PMID:24920279

  14. 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.

  15. Ephemeral Gully Headcut Development and Migration in Stratified Soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were conducted to examine the effect of vertical stratification in soil erodibility on the development and migration of steady-state headcut scour holes in upland concentrated flows typical of agricultural fields. Packed soil beds with a pre-formed step were subjected to identical simul...

  16. Microbial enzyme activities of peatland soils in south central Alaska lowlands

    EPA Science Inventory

    Microbial enzyme activities related to carbon and nutrient acquisition were measured on Alaskan peatland soils as indicators of nutrient limitation and biochemical sustainability. Peat decomposition is mediated by microorganisms and enzymes that in turn are limited by various ph...

  17. Evaluation of the changes induced by gasification biochar in a peat-sand substrate

    NASA Astrophysics Data System (ADS)

    Muter, Olga; Lebedeva, Galina; Telysheva, Galina

    2014-10-01

    Gasification biochar represents one of the biochar types tested for agricultural needs. The aim of this study was to clarify the physico-chemical and biological changes occurring in a peat-sand substrate amended with hardwood-derived gasification biochar in the rates of 2, 4 and 20 g l-1. The pH(H2O) of the substrate with 4 g l-1 and 20 g l-1 biochar was increased from 5.6 to 6.2 and 6.7, respectively. The testing of the substrate in the respirometry device showed that the increase in the biochar rate led to a decrease in the amount of CO2 evolved at the maximum pressure drop. The continuous decrease in pressure observed in the respirometry bottles filled with pure biochar allows explaining this effect by biochar sorption activity. Addition of 2 and 4 g l-1 biochar to the peat-sand substrate stimulated the growth of cucumbers in an 18-day pot vegetation experiment. An increase in the number of root tips and root volume with a decreasing average root diameter was shown in the presence of biochar. Stimulation of plant growth on the background of low rates of biochar requires a further study with emphasis on the specific combination of biochar, soil type, plant species, and climatic conditions.

  18. Environmental impact assessment of peat fires on the water quality in Western Siberia

    NASA Astrophysics Data System (ADS)

    Kharanzhevskaya, Yulia; Voistinova, Elena; Sinyutkina, Anna

    2014-05-01

    Each year, on the earth arises to 4,000,000 fires, damaging about 0.5% of the total forest area and released into the atmosphere millions of tons of products of combustion. At present in the Russian Federation fires in drained marsh areas acquired catastrophic proportions and have become a real environmental disaster. They arise, and covering a large area, causing not only the destruction of fertile soils, but also a haze of cities and towns. The problem of forest and peat fires is also very relevant for the Tomsk region. As practice shows, the number of separate fires, or large-scale fires, not decreasing year by year, despite improvements in forecasting systems of forest fire danger. Since 1989, there was a strong trend towards increasing the number we burn forests and destructive crown fires. In recent years fires occur in more outlying and boggy territory, complicating delivery technology for their localization. Thus, the problem of forecasting and extinguishing fires remains open. On the second place is the problem of the influence of forest and peat fires on the ecological situation in the region and assess recovery area after the fire. As shown by studies conducted in the area of burned bog in Iksa River Basin (Tomsk region), peat fires determine the appearance of high concentrations of organic matter (COD 189.7 mgO / l) and some heavy metals in the bog waters. Combustion of peat deposits facilitates transition lead to more mobile forms by complexation with humic substances swamp waters. As a result, burns noted a high level of lead (0.015 mg / L) is 25 times higher than background typical of bog water. Preliminary studies have shown that the problem of fires and their implications on ecological situation in region is especially unpleasant due to bad transport access certain areas of fire risk and fire hazard assessment requires new approaches and detailed studies. In our opinion, the basis for assessing fire hazard area must be put to a specific list of features natural landscapes, which should include an evaluation of the probability of occurrence and spread of fire.

  19. Restructuring of a Peat in Interaction with Multivalent Cations: Effect of Cation Type and Aging Time

    PubMed Central

    Kunhi Mouvenchery, Yamuna; Jaeger, Alexander; Aquino, Adelia J. A.; Tunega, Daniel; Diehl, Dörte; Bertmer, Marko; Schaumann, Gabriele Ellen

    2013-01-01

    It is assumed to be common knowledge that multivalent cations cross-link soil organic matter (SOM) molecules via cation bridges (CaB). The concept has not been explicitly demonstrated in solid SOM by targeted experiments, yet. Therefore, the requirements for and characteristics of CaB remain unidentified. In this study, a combined experimental and molecular modeling approach was adopted to investigate the interaction of cations on a peat OM from physicochemical perspective. Before treatment with salt solutions of Al3+, Ca2+ or Na+, respectively, the original exchangeable cations were removed using cation exchange resin. Cation treatment was conducted at two different values of pH prior to adjusting pH to 4.1. Cation sorption is slower (>>2 h) than deprotonation of functional groups (<2 h) and was described by a Langmuir model. The maximum uptake increased with pH of cation addition and decreased with increasing cation valency. Sorption coefficients were similar for all cations and at both pH. This contradicts the general expectations for electrostatic interactions, suggesting that not only the interaction chemistry but also spatial distribution of functional groups in OM determines binding of cations in this peat. The reaction of contact angle, matrix rigidity due to water molecule bridges (WaMB) and molecular mobility of water (NMR analysis) suggested that cross-linking via CaB has low relevance in this peat. This unexpected finding is probably due to the low cation exchange capacity, resulting in low abundance of charged functionalities. Molecular modeling demonstrates that large average distances between functionalities (?3 nm in this peat) cannot be bridged by CaB-WaMB associations. However, aging strongly increased matrix rigidity, suggesting successive increase of WaMB size to connect functionalities and thus increasing degree of cross-linking by CaB-WaMB associations. Results thus demonstrated that the physicochemical structure of OM is decisive for CaB and aging-induced structural reorganisation can enhance cross-link formation. PMID:23750256

  20. Restructuring of a peat in interaction with multivalent cations: effect of cation type and aging time.

    PubMed

    Kunhi Mouvenchery, Yamuna; Jaeger, Alexander; Aquino, Adelia J A; Tunega, Daniel; Diehl, Dörte; Bertmer, Marko; Schaumann, Gabriele Ellen

    2013-01-01

    It is assumed to be common knowledge that multivalent cations cross-link soil organic matter (SOM) molecules via cation bridges (CaB). The concept has not been explicitly demonstrated in solid SOM by targeted experiments, yet. Therefore, the requirements for and characteristics of CaB remain unidentified. In this study, a combined experimental and molecular modeling approach was adopted to investigate the interaction of cations on a peat OM from physicochemical perspective. Before treatment with salt solutions of Al(3+), Ca(2+) or Na(+), respectively, the original exchangeable cations were removed using cation exchange resin. Cation treatment was conducted at two different values of pH prior to adjusting pH to 4.1. Cation sorption is slower (>2 h) than deprotonation of functional groups (<2 h) and was described by a Langmuir model. The maximum uptake increased with pH of cation addition and decreased with increasing cation valency. Sorption coefficients were similar for all cations and at both pH. This contradicts the general expectations for electrostatic interactions, suggesting that not only the interaction chemistry but also spatial distribution of functional groups in OM determines binding of cations in this peat. The reaction of contact angle, matrix rigidity due to water molecule bridges (WaMB) and molecular mobility of water (NMR analysis) suggested that cross-linking via CaB has low relevance in this peat. This unexpected finding is probably due to the low cation exchange capacity, resulting in low abundance of charged functionalities. Molecular modeling demonstrates that large average distances between functionalities (?3 nm in this peat) cannot be bridged by CaB-WaMB associations. However, aging strongly increased matrix rigidity, suggesting successive increase of WaMB size to connect functionalities and thus increasing degree of cross-linking by CaB-WaMB associations. Results thus demonstrated that the physicochemical structure of OM is decisive for CaB and aging-induced structural reorganisation can enhance cross-link formation. PMID:23750256

  1. Suggested protocol for collecting, handling and preparing peat cores and peat samples for physical, chemical, mineralogical and isotopic analyses.

    PubMed

    Givelet, Nicolas; Le Roux, Gaël; Cheburkin, Andriy; Chen, Bin; Frank, Jutta; Goodsite, Michael E; Kempter, Heike; Krachler, Michael; Noernberg, Tommy; Rausch, Nicole; Rheinberger, Stefan; Roos-Barraclough, Fiona; Sapkota, Atindra; Scholz, Christian; Shotyk, William

    2004-05-01

    For detailed reconstructions of atmospheric metal deposition using peat cores from bogs, a comprehensive protocol for working with peat cores is proposed. The first step is to locate and determine suitable sampling sites in accordance with the principal goal of the study, the period of time of interest and the precision required. Using the state of the art procedures and field equipment, peat cores are collected in such a way as to provide high quality records for paleoenvironmental study. Pertinent field observations gathered during the fieldwork are recorded in a field report. Cores are kept frozen at -18 degree C until they can be prepared in the laboratory. Frozen peat cores are precisely cut into 1 cm slices using a stainless steel band saw with stainless steel blades. The outside edges of each slice are removed using a titanium knife to avoid any possible contamination which might have occurred during the sampling and handling stage. Each slice is split, with one-half kept frozen for future studies (archived), and the other half further subdivided for physical, chemical, and mineralogical analyses. Physical parameters such as ash and water contents, the bulk density and the degree of decomposition of the peat are determined using established methods. A subsample is dried overnight at 105 degree C in a drying oven and milled in a centrifugal mill with titanium sieve. Prior to any expensive and time consuming chemical procedures and analyses, the resulting powdered samples, after manual homogenisation, are measured for more than twenty-two major and trace elements using non-destructive X-Ray fluorescence (XRF) methods. This approach provides lots of valuable geochemical data which documents the natural geochemical processes which occur in the peat profiles and their possible effect on the trace metal profiles. The development, evaluation and use of peat cores from bogs as archives of high-resolution records of atmospheric deposition of mineral dust and trace elements have led to the development of many analytical procedures which now permit the measurement of a wide range of elements in peat samples such as lead and lead isotope ratios, mercury, arsenic, antimony, silver, molybdenum, thorium, uranium, rare earth elements. Radiometric methods (the carbon bomb pulse of (14)C, (210)Pb and conventional (14)C dating) are combined to allow reliable age-depth models to be reconstructed for each peat profile. PMID:15152318

  2. Long-term carbon accumulation in tropical peat swamp forests in Indonesia

    NASA Astrophysics Data System (ADS)

    Kurnianto, S.; Warren, M.; Talbot, J.; Kaufman, B.; Frolking, S.; Murdiyarso, D.

    2012-12-01

    Almost half of the tropical peatland area is located in Indonesia, which historically was mostly covered by tropical peat swamp forests. Indonesian peat swamp forest cover has decreased at a rate of 2% per year, implying large carbon emissions into the atmosphere. Here we report on peat core carbon content data collected in summer 2012 in pristine peat swamp forest in Tanjung Puting National Park, West Kalimantan, in an oil palm plantation near Tanjung Puting, and in pristine peat swamp forest in Berbak National Park, Jambi, Sumatra. We also present long-term peat carbon accumulation simulation results using the Holocene Peat Model (HPM), which we have modified to be applicable for tropical peat forest settings. We compare the HPM results with the field data collected in West Kalimantan and Jambi, Indonesia.

  3. 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.

  4. 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.

  5. The influence of wind farm development on the hydrochemistry and ecology of an upland stream.

    PubMed

    Millidine, K J; Malcolm, I A; McCartney, A; Laughton, R; Gibbins, C N; Fryer, R J

    2015-08-01

    Despite perceptions of pristine condition, upland environments are increasingly subject to a range of anthropogenic pressures including air pollution, climate change, land-use change and evolving land management strategies. Although they have received little attention to date, the large-scale development of upland wind farms also has the potential to disturb vegetation and soils, alter hydrology and water quality and, thus, impact freshwater ecosystems. This paper presents the findings of a 5-year study of the impacts of wind farm construction on the freshwater environment. Data on water quality, invertebrate and fish populations were collected for 2 years before construction and for the following 3 years covering the construction period and the initial period of the farm's operation. In contrast to previous studies, the impacts of the wind farm development were assessed for a suite of potentially affected hydrochemical variables using a before-after-control-impact (BACI) analysis that allowed separation of construction effects from spatial and temporal variability in hydroclimatological conditions, thereby providing an improved, more robust evidence base. There was a small but significant negative effect of construction on pH, alkalinity (Alk) and acid neutralising capacity (ANC) in the upper part of the treatment catchment, which was where the wind farm was situated. The effects were more marked under higher flow conditions. It is hypothesised that this reflects changes in hydrological processes with increased near-surface runoff or organic acid mobilisation. There was no indication that either invertebrate community structure or fish densities were impacted by construction and the resulting effects on water quality. PMID:26205284

  6. Mixed Grazing Systems Benefit both Upland Biodiversity and Livestock Production

    PubMed Central

    Fraser, Mariecia D.; Moorby, Jon M.; Vale, James E.; Evans, Darren M.

    2014-01-01

    Background With world food demand expected to double by 2050, identifying farming systems that benefit both agricultural production and biodiversity is a fundamentally important challenge for the 21st century, but this has to be achieved in a sustainable way. Livestock grazing management directly influences both economic outputs and biodiversity on upland farms while contributing to potentially damaging greenhouse gas emissions, yet no study has attempted to address these impacts simultaneously. Methods Using a replicated, landscape-scale field experiment consisting of five management ‘systems’ we tested the effects of progressively altering elements within an upland farming system, viz i) incorporating cattle grazing into an upland sheep system, ii) integrating grazing of semi-natural rough grazing into a mixed grazing system based on improved pasture, iii) altering the stocking ratio within a mixed grazing system, and iv) replacing modern crossbred cattle with a traditional breed. We quantified the impacts on livestock productivity and numbers of birds and butterflies over four years. Results, Conclusion and Significance We found that management systems incorporating mixed grazing with cattle improve livestock productivity and reduce methane emissions relative to sheep only systems. Systems that also included semi-natural rough grazing consistently supported more species of birds and butterflie