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1

Modelling the role of humic acid in radiocaesium distribution in a British upland peat soil  

Microsoft Academic Search

The significance of exchange sites on organic matter in the retention of radiocaesium in highly organic soils remains unclear. To quantify this retention, we measured the binding of 134Cs to a humic acid isolated from a British upland peat soil, under a range of chemical conditions. We interpreted our results using Humic Ion Binding Model V, a model of humic

S. Lofts; E. W. Tipping; A. L. Sanchez; B. A. Dodd

2002-01-01

2

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

PubMed

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

Yallop, A R; Clutterbuck, B

2009-06-01

3

Modelling the role of humic acid in radiocaesium distribution in a British upland peat soil.  

PubMed

The significance of exchange sites on organic matter in the retention of radiocaesium in highly organic soils remains unclear. To quantify this retention, we measured the binding of 134Cs to a humic acid isolated from a British upland peat soil, under a range of chemical conditions. We interpreted our results using Humic Ion Binding Model V, a model of humic substance chemistry which simulates ion exchange by non-specific accumulation of cations adjacent to the humic molecules. Model V could simulate the humic acid-solution partitioning of Cs under all the solution conditions used. The model was used to estimate the contribution of organic matter to Cs sorption by the whole soil composite. An estimate of Cs sorption by illite frayed edge sites was also made. These simulations show that organic matter may play only a minor role in binding Cs. even in highly organic soils. PMID:12066976

Loft, S; Tipping, E W; Sanchez, A L; Dodd, B A

2002-01-01

4

Hydraulic conductivity in upland blanket peat: measurement and variability  

NASA Astrophysics Data System (ADS)

A key parameter used in wetland hydrological and landform development models is hydraulic conductivity. Head recovery tests are often used to measure hydraulic conductivity, but the calculation techniques are usually confined to rigid soil theory. This is despite reports demonstrating the misapplication of rigid soil theory to non-rigid soils such as peats. Although values of hydraulic conductivity calculated using compressible techniques have been presented for fenland peats, these data have never, to the authors' knowledge, been compared with such calculations in other peat types. Head recovery tests (slug withdrawal) were performed on piezometers at depths ranging from 10 to 80 cm from the surface on north Pennines blanket peats. Results were obtained using both rigid and compressible soil theories, thus allowing comparison of the two techniques. Compressible soil theory gives values for hydraulic conductivity that are typically a factor of five times less than rigid soil calculations. Hydraulic conductivity is often assumed to decrease with depth in upland peats, but at the study site in the northern Pennines it was not found to vary significantly with depth within the range of peat depths sampled. The variance within depth categories was not significantly different to the variance between depth categories showing that individual peat layers did not have characteristic hydraulic conductivity values. Thus, large lateral and vertical differences in hydraulic conductivity over short distances create problems for modelling but may help account for the high frequency of preferential flow pathways within what is otherwise a low matrix hydraulic conductivity peat. Hydraulic conductivity was found to vary significantly between sampling sites, demonstrating that hillslope- or catchment-scale variability may be more important than plot-scale variability. Values for compressibility of the peats are also reported. These generally decline with depth, and they also vary significantly between sampling sites. There are implications for the way in which measurements of hydraulic conductivity and other properties of blanket peat are interpreted, as the effects of environmental change in one part of a peat catchment may be very different to those in another.

Holden, J.; Burt, T. P.

2003-04-01

5

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

NASA Astrophysics Data System (ADS)

The response of large stores of carbon in boreal forest soils to global warming is a major uncertainty in predicting the future carbon budget. We measured the temperature dependence of decomposition for upland boreal peat under black spruce forest with sphagnum and feather moss understory using incubation experiments. CO2 efflux rates clearly responded to temperature, which ranged from -10° to +8°C by ˜2°C increments. At temperatures below 0°C, significant decomposition was observed in feather moss peat but not in wetter sphagnum peat. Above 0°C, decomposition was exponentially related to temperature, corresponding to a Q(10) (the ratio of the rate of CO2 evolution at one temperature divided by that at a temperature 10°C cooler) of 4.4 for feather moss and 3.1 for sphagnum peat. The greatest change in CO2 evolution rate with temperature occurred between -2° and 0°C, which coincided with the phase transition of soil water. We saw no large change in the rate of CO2 evolution between incubation experiments separated by a 6 month storage period for feather moss peat. Stable C isotope measurements of evolved CO2 and the rate of change of CO2 evolution with time suggest different substrates are used to sustain heterotrophic respiration above and below freezing. Radiocarbon signatures of CO2 respired from both types of peat reflected significant contributions from C fixed in the last 35 years ("bomb" 14C) as well as C fixed prior to 1950. We observed no change in the ?14C of respired CO2 with temperature. Isotopic signatures of peat components showed that a combination of substrates must contribute to the CO2 evolved in our incubations. Decomposition of fine roots (which made up less than 7% of the total peat C) accounted for ˜50% of respired CO2 in feather moss peat and for ˜30% of respired CO2 in sphagnum peat. Fine-grained (<1 mm), more humified material that makes up 60-70% of the bulk peat organic carbon contributed significantly to heterotrophic respiration (˜30% in feather moss and ˜50% in sphagnum moss peat), despite slow decomposition rates. Increased temperatures caused enhanced decomposition from all pools without changing their relative contributions. Because the contribution of peat decomposition is a small portion of total soil respiration at the study site, increased respiration rates would be difficult to measure as increased fluxes in the field. Nonetheless, sustained warming could lead to significant loss of C from these peat layers.

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

2002-02-01

6

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

NASA Astrophysics Data System (ADS)

The response of large stores of carbon in boreal forest soils to global warming is a major uncertainty in predicting the future carbon budget. We measured the temperature dependence of decomposition for upland boreal peat under black spruce forest with sphagnum and feather moss understory using incubation experiments. CO2 efflux rates clearly responded to temperature, which ranged from -10° to +8°C by ~2°C increments. At temperatures below 0°C, significant decomposition was observed in feather moss peat but not in wetter sphagnum peat. Above 0°C, decomposition was exponentially related to temperature, corresponding to a Q(10) (the ratio of the rate of CO2 evolution at one temperature divided by that at a temperature 10°C cooler) of 4.4 for feather moss and 3.1 for sphagnum peat. The greatest change in CO2 evolution rate with temperature occurred between -2° and 0°C, which coincided with the phase transition of soil water. We saw no large change in the rate of CO2 evolution between incubation experiments separated by a 6 month storage period for feather moss peat. Stable C isotope measurements of evolved CO2 and the rate of change of CO2 evolution with time suggest different substrates are used to sustain heterotrophic respiration above and below freezing. Radiocarbon signatures of CO2 respired from both types of peat reflected significant contributions from C fixed in the last 35 years (``bomb'' 14C) as well as C fixed prior to 1950. We observed no change in the ?14C of respired CO2 with temperature. Isotopic signatures of peat components showed that a combination of substrates must contribute to the CO2 evolved in our incubations. Decomposition of fine roots (which made up less than 7% of the total peat C) accounted for ~50% of respired CO2 in feather moss peat and for ~30% of respired CO2 in sphagnum peat. Fine-grained (<1 mm), more humified material that makes up 60-70% of the bulk peat organic carbon contributed significantly to heterotrophic respiration (~30% in feather moss and ~50% in sphagnum moss peat), despite slow decomposition rates. Increased temperatures caused enhanced decomposition from all pools without changing their relative contributions. Because the contribution of peat decomposition is a small portion of total soil respiration at the study site, increased respiration rates would be difficult to measure as increased fluxes in the field. Nonetheless, sustained warming could lead to significant loss of C from these peat layers.

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

2003-02-01

7

Soil zonality of the Chukotka Upland  

NASA Astrophysics Data System (ADS)

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.

Karavaeva, N. A.

2013-05-01

8

The role of common upland vegetation on gaseous carbon cycling on UK blanket peat bogs  

NASA Astrophysics Data System (ADS)

The most important control upon the carbon dynamics of any peatland is vegetation. However there is a gap in the literature with respect to comparative, in-situ studies of common upland vegetation types on peat bogs from a carbon cycling perspective. Where studies exist they tend to be narrowly focused (i.e. on one or two species or a small geographical area) or are laboratory manipulation studies. This study set out to compare gaseous CO2 exchange, in situ, across a broad (geographic) range of sites dominated by differing, common, upland vegetation types. The vegetation types studied were; Calluna vulgaris, Sphagnum spp., Eriophorum (E. angustifolium + E. vaginatum), Molinia caerulea and areas revegetated with a lawn grass mixture that was used for restoration (Festuca spp, Deschampsia spp. and Agrostis spp.).The primary aim of the study was to assess the carbon cycling potential of the common upland vegetation types, in order to produce clearer evidence as to which upland species produce the most efficient carbon sinks. The study was carried out in the South Pennines and Peak District of England. All readings were taken from upland-blanket peat bogs, as this type of bog accounts for 87% of the UK's peatlands, and therefore the results of this study can have the widest possible applicability to the rest of the UK's peat reserves. NEE and NER measurements were taken with a PP Systems EMG-4 infra-red gas analyzer. PAR and air temperature readings were taken along side water table and soil pore water samples from every site. Each site was visited monthly for at least 12 months and between 3-9 replicates were recorded per site. The results of this study will deal with the effects vegetation has on NER, GPP and NEE, focusing on which vegetation types make the most efficient gaseous carbon sinks. Moreover the effect of vegetation on water table levels and water quality will be discussed. Finally a consideration of how the age of Calluna vulgaris affects the parameters above will be given.

Dixon, Simon; Rowson, James; Worrall, Fred

2010-05-01

9

Extreme peat burning along peatland-upland interfaces of the Western Boreal Plain  

NASA Astrophysics Data System (ADS)

Wildfire is the largest disturbance affecting peatlands in the Western Boreal Forest, releasing 4700 Gg C a-1 over ~1500 km2 annually. Under future climate scenarios the amount of area burned in this region is forecast to increase by 25-100%, potentially converting these ecosystems into a regional net source of carbon to the atmosphere. During wildfire, the majority of carbon released from peatlands is attributable to peat smouldering with burn depths generally ranging from 5 - 20 cm of peat. However, no study has documented the incidence of an extreme smouldering event and the conditions necessary for such an event to occur. Here we report on a smouldering event during the Utikuma Complex forest fire (SWF-060, ~90,000 ha) in May, 2011 at the Utikuma Lake Research Study Area (URSA) in Alberta's Western Boreal Plain, where peat burn depths exceeded one meter along a peatland-upland interface (range = 0.12 to 1.10 m, mean = 0.54 m). We applied the Peat Smouldering and Ignition model (PSI) at an adjacent unburned peatland-upland interface to characterize the hydrological and hydrophysical conditions necessary for these extreme burn depths. Model outputs indicate that the coupling of dense peat (bulk density > 150 kg m-3) and low peat moisture (GWC < 250%) allow for severe smouldering to propagate deep into the peat profile. We argue that peatland-upland interfaces, which likely release ten times more carbon per meter squared than peatland centers, are hotspots for peat smouldering due to dynamic hydrological conditions that reduce the moisture content of high-density peat during dry periods. We suggest the hydrogeological setting of peatlands is essential for identifying peatland-upland interfaces as areas highly vulnerable to smouldering and for assisting fire managers and scientists in predicting and mitigating the effects of extreme peat burning events. Burned peatland-upland interface

Lukenbach, M.; Hokanson, K.; Devito, K. J.; Kettridge, N.; Thompson, D.; Petrone, R. M.; Waddington, J. M.

2013-12-01

10

The role of common upland vegetation on gaseous carbon cycling on UK blanket peat bogs  

Microsoft Academic Search

The most important control upon the carbon dynamics of any peatland is vegetation. However there is a gap in the literature with respect to comparative, in-situ studies of common upland vegetation types on peat bogs from a carbon cycling perspective. Where studies exist they tend to be narrowly focused (i.e. on one or two species or a small geographical area)

Simon Dixon; James Rowson; Fred Worrall

2010-01-01

11

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

NASA Astrophysics Data System (ADS)

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

Aitkenhead, Matt; Saunders, Matt; Yeluripati, Jagadeesh

2014-05-01

12

Spectrophotometric properties of surface water dissolved organic matter in an afforested upland peat catchment  

Microsoft Academic Search

Many upland catchments in the UK have undergone afforestation; their characteristic waterlogged soils require extensive pre-plantation ground drainage to allow tree establishment. In peatland areas this can result in very highly coloured runoff and enhanced dissolved organic matter (DOM) export in rivers of naturally high concentrations. In 1966, the Coalburn Experimental Catchment, northern England, was established to investigate the impact

Andy Baker; Lucy Bolton; Malcolm Newson; Robert G. M. Spencer

2008-01-01

13

Adoption of soil conservation: the case of the Philippine uplands  

Microsoft Academic Search

Soil degradation in the sloping uplands of Asia is a serious problem that threatens the sustainability of agriculture. Although several soil conservation technologies have been developed and promoted, their adoption has not been widespread. A micro-economic analysis of adoption of contour hedgerows by upland farmers in the Philippines is conducted to identify the factors that determine adoption. The empirical results

Ma. Lucila A. Lapar; Sushil Pandey

1999-01-01

14

Controlled drainage on a cultivated peat soil  

NASA Astrophysics Data System (ADS)

Controlled drainage can delay the decomposition of organic material in peat soils, as high water table means a thin oxidized layer in the soil surface. Therefore, greenhouse gas emissions, and mineralization of nutrients will be decreased. There will also be less outflow from the field. These mean less nutrient leaching. However, controlled drainage systems may not always manage to keep the water table on the desired level in practical field conditions. In this study, the water tables in two controlled drainage systems were monitored on a cultivated peat soil in southern Finland around a year. Results show how the water table reacts to the changes of the water height in the control wells, and to the surrounding weather conditions. The data collection is still going on.

Myllys, Merja; Regina, Kristiina

2014-05-01

15

Correspondence between vegetation and soils in wetlands and nearby uplands  

USGS Publications Warehouse

The association between vegetation and soils from a geographically broad sampling of wetlands and adjoining uplands is reported for 38 hydric and 26 nonhydric soils, as recognized in the hydric soils list of the Soil Conservation Service. Wetlands represented in the study include estuaries, pitcher plant bogs, prairie depressional wetlands, and western riparian lands. The agreement between vegetation and soils is clear with few exceptions. In general, hydric soils support hydrophytic plant communities, and nonhydric soils support upland communities. Only 10% of the hydric soils sampled support upland communities and only 15% of the nonhydric soils support wetland communities. Exceptions to the correspondence between vegetation and soils are discussed; local hydrology, the transitional nature of some soils, and other determinants of wetland vegetation structure (e.g., salinity, disturbance) seem to account for many of the observed discrepancies. A method that simplifies the complexity of soils and vegetation cannot be expected to represent accurately all details of their interrelations.

Scott, Michael L.; Slauson, William L.; Segelquist, Charles A.; Auble, Gregor T.

1989-01-01

16

Metatranscriptomic Analysis of Arctic Peat Soil Microbiota  

PubMed Central

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

Tveit, Alexander T.

2014-01-01

17

Phosphorus management for perennial crops in central Amazonian upland soils  

Microsoft Academic Search

The present contribution discusses the soil P status of central Amazonian upland soils, the effects of tree crops on soil P availability and the factors controlling soil P cycling in land use systems with tree crops. Soil fertility management has to target the prevalent P deficiency by adequate P fertilization, especially in southern and northern municipalities of central Amazônia where

Johannes Lehmann; Manoel da Silva Cravo; Jeferson Luiz Vasconselos de Macêdo; Adônis Moreira; Götz Schroth

2001-01-01

18

Peat soil properties and erodibility: what factors affect erosion and suspended sediment yields in peat extraction areas?  

NASA Astrophysics Data System (ADS)

Peatland drainage and peat extraction operations change soil properties and expose bare peat to erosion forces, resulting in increased suspended sediment (SS) loads to downstream water bodies. SS yields from peat extraction areas are known to vary significantly between sites, but the contribution of peat properties and catchment characteristics to this variation is not well understood. In this study, we investigated peat erosion at 20 Finnish peat extraction sites by conducting in situ and laboratory measurements on peat erodibility and associated peat properties (degree of humification, peat type, bulk density, loss on ignition, porosity, moisture content, and shear strength), and by comparing the results with monitored long-term SS concentrations and loads at each catchment outlet. Here, we used a cohesive strength meter (CSM) to measure direct erosion thresholds for undisturbed soil cores collected from each study site. The results suggested that the degree of peat decomposition clearly affects peat erodibility and explains much of the variation in SS concentration between the study sites. According to CSM tests, critical shear stresses for particle entrainment were lowest (on average) in well-decomposed peat samples, while undecomposed, dry and fiber rich peat generally resisted erosion very well. Furthermore, the results indicated that two separate critical shear stresses often exist in moderately decomposed peat. In these cases, the well-decomposed parts of peat samples eroded first at relatively low shear stresses and remaining peat fibers prevented further erosion until a much higher shear stress was reached. In addition to peat soil properties, the study showed that the erosion of mineral subsoil may play a key role in runoff water SS concentration at peat extraction areas with drainage ditches extending into the mineral soil. The interactions between peat properties and peat erodibility found in this study as well as critical shear stress values obtained can be used for several purposes in e.g. water conservation and sediment management planning for peat extraction areas and other bare peat-covered catchments.

Tuukkanen, Tapio; Marttila, Hannu; Kløve, Bjørn

2014-05-01

19

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

NASA Astrophysics Data System (ADS)

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.

Mezhibor, Antonina; Podkozlin, Ivan

2013-04-01

20

Properties of Stabilized Peat by Soil-Cement Column Method  

Microsoft Academic Search

A field model study has been carried out to stabilise peat soil using various types of binder by deep mixing method and to investigate its effect on engineering properties. Some soil-cement model columns have been constructed at site and different mechanical properties of stabilised peat, like undrained shear strength, unconfined compressive strength and shear strength was determined after 14 days

Roslan Hashim; Shahidul Islam

21

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

NASA Astrophysics Data System (ADS)

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.

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

2010-05-01

22

PRESERVATION OF PEAT SOIL BY CULTIVATION OF PERENNIAL HERBAGE CROPS  

Microsoft Academic Search

On a peat-soil of the reclaimed Hula Valley swamp containing 30-40% organic matter,, 1.5% of N, C\\/N ratio of 10 and pH = 6-6.5 three varieties of Guinea grass, alfalfa and Rhodes grass were grown. The aim of the research was to preserve the peat-soil from the prevailing aerobic oxidation, wind and water erosion and minimize the typical nitrate accumulation,

Dan Levanon; Israel Levin

23

Are calcareous soils in uplands less prone to damage from road salting than acidic soils?  

Microsoft Academic Search

Previous studies of upland roadside soils in Cumbria, that would normally be naturally acidic, have highlighted that (a) runoff from roads subjected to long-term road salting can dramatically raise soil pH down slope in upland areas; (b) the soil pH increase dramatically changes N cycling in soils down slope, increasing mineralisation of organic matter, ammonification, ammonium leaching down slope and

Sophie M. Green; Malcolm S. Cresser

2008-01-01

24

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

NASA Astrophysics Data System (ADS)

Knowledge about hydraulic properties of organic soils is crucial for the interpretation of the hydrological situation in peatlands. This in turn is the basis for designing optimal rewetting strategies, for assessing the current and future climatic water balance and for quantifying greenhouse gas emissions of CO2, CH4 and N2O, which are strongly controlled by the depth of the peat water table. In contrast to mineral soils, the hydraulic properties of organic soils differ in several aspects. Due to the high amount of organic components, strong heterogeneity, and shrinkage and swelling of peat, accompanied by changing soil volume and bulk density, the applicability of standard hydraulic functions developed for mineral soils for describing peat soil moisture dynamics is often questioned. Hence, the objective of this study was to investigate the applicability of the commonly applied van Genuchten-Mualem (VGM) parameterization and to evaluate model errors for various peat types. Laboratory column experiments with undisturbed peat soils (diameter: 30 cm, height: 20 cm) from 5 different peatlands in Germany were conducted. In numerical simulations using HYDRUS-1D the experimental data were used for an inverse estimation of the soil hydraulic parameters. Using the VGM parameterization, the model errors between observed and measured pressure heads were quantified with a root mean square error (RMSE) of 20 - 65 cm. The RMSE increased for soils with higher organic carbon content and higher porosity. Optimizing the VGM 'tortuosity' parameter (?) instead of fixing it to its default of 0.5 strongly reduced the RMSE, especially for the soils that showed high pressure head gradients during the experiment. Due to the fact, that very negative pressure heads in peatlands occur rarely, we reduced the range of pressured heads in the inversion to a 'field-relevant' range from 0 to -200 cm which strongly reduced the RMSE to 6 - 12 cm and makes the VGM parameterization applicable for all investigated peat soils. For the field-relevant scale, especially for very wet conditions, we demonstrate the importance of macro-pores by using a simple macro-pore approach, with only 1 additional parameter, i.e. the macro-pore fraction, which strongly reduced the RMSE down to 1 - 7 cm. Since ? has not been identified as an important parameter for the field-relevant range, only 5 parameters were optimized in this approach. This keeps the derivation of the parameters manageable and thus provides a model that is applicable to practical issues.

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

2013-12-01

25

Deccesion of peat-moorsh soils under different land use  

Microsoft Academic Search

Use of peatlands has a serious impact on soil properties as well as on loss of organic matter. On the basis of survey carried out in 1976, 1993 and 2001 in the Mrowla river valley near Rzeszow, authors analysed changes of the peat-moorsh soils under different land use. The 25- year period was analysed. Survey results comprised: loss of organic

K. Lipka; E. Zajac

2009-01-01

26

Diversity and Activity of Methanotrophic Bacteria in Different Upland Soils  

PubMed Central

Samples from diverse upland soils that oxidize atmospheric methane were characterized with regard to methane oxidation activity and the community composition of methanotrophic bacteria (MB). MB were identified on the basis of the detection and comparative sequence analysis of the pmoA gene, which encodes a subunit of particulate methane monooxygenase. MB commonly detected in soils were closely related to Methylocaldum spp., Methylosinus spp., Methylocystis spp., or the “forest sequence cluster” (USC ?), which has previously been detected in upland soils and is related to pmoA sequences of type II MB (Alphaproteobacteria). As well, a novel group of sequences distantly related (<75% derived amino acid identity) to those of known type I MB (Gammaproteobacteria) was often detected. This novel “upland soil cluster ?” (USC ?) was significantly more likely to be detected in soils with pH values of greater than 6.0 than in more acidic soils. To identify active MB, four selected soils were incubated with 13CH4 at low mixing ratios (<50 ppm of volume), and extracted methylated phospholipid fatty acids (PLFAs) were analyzed by gas chromatography-online combustion isotope ratio mass spectrometry. Incorporation of 13C into PLFAs characteristic for methanotrophic Gammaproteobacteria was observed in all soils in which USC ? sequences were detected, suggesting that the bacteria possessing these sequences were active methanotrophs. A pattern of labeled PLFAs typical for methanotrophic Alphaproteobacteria was obtained for a sample in which only USC ? sequences were detected. The data indicate that different MB are present and active in different soils that oxidize atmospheric methane. PMID:14602631

Knief, Claudia; Lipski, Andre; Dunfield, Peter F.

2003-01-01

27

Deccesion of peat-moorsh soils under different land use  

NASA Astrophysics Data System (ADS)

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

Lipka, K.; Zaj?c, E.

2009-04-01

28

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 from fire and permafrost-thaw chronosequences in upland Picea mariana stands near Hess Creek and Tok

Ickert-Bond, Steffi

29

Regional patterns of well drained upland soil differentiation in the middle Caquetá basin of Colombian Amazonia  

Microsoft Academic Search

As part of a land-ecological survey of the middle Caquetá basin in Colombian Amazonia, a total of 41 well drained upland soil profiles under primary rain forest was studied. Two soil groups were recognised on the basis of principal components analysis (PCA). Soils pertaining to the first group cover about 45–60% of the well drained uplands and classify as Afsols

Johanna M. Lips; Joost F. Duivenvoorden

1996-01-01

30

Turnover time of microbial biomass carbon in Japanese upland soils with different textures  

Microsoft Academic Search

We investigated the turnover time of microbial biomass-C in Japanese upland soils with various textures and examined the soil physicochemical properties influencing their turnover time. Samples from five different soil types (sand-dune regosol, light-colored Andosol, humic Andosol, brown forest soil, and dark red soil) were taken from upland concrete-frame plots in the experimental field of Chiba University. Each soil amended

Kazunori Sakamoto; Naoko Hodono

2000-01-01

31

[Response of mineralization of dissolved organic carbon to soil moisture in paddy and upland soils in hilly red soil region].  

PubMed

Typical paddy and upland soils were collected from a hilly subtropical red-soil region. 14C-labeled dissolved organic carbon (14C-DOC) was extracted from the paddy and upland soils incorporated with 14C-labeled straw after a 30-day (d) incubation period under simulated field conditions. A 100-d incubation experiment (25 degrees C) with the addition of 14C-DOC to paddy and upland soils was conducted to monitor the dynamics of 14C-DOC mineralization under different soil moisture conditions [45%, 60%, 75%, 90%, and 105% of the field water holding capacity (WHC)]. The results showed that after 100 days, 28.7%-61.4% of the labeled DOC in the two types of soils was mineralized to CO2. The mineralization rates of DOC in the paddy soils were significantly higher than in the upland soils under all soil moisture conditions, owing to the less complex composition of DOC in the paddy soils. The aerobic condition was beneficial for DOC mineralization in both soils, and the anaerobic condition was beneficial for DOC accumulation. The biodegradability and the proportion of the labile fraction of the added DOC increased with the increase of soil moisture (45% -90% WHC). Within 100 days, the labile DOC fraction accounted for 80.5%-91.1% (paddy soil) and 66.3%-72.4% (upland soil) of the cumulative mineralization of DOC, implying that the biodegradation rate of DOC was controlled by the percentage of labile DOC fraction. PMID:24984493

Chen, Xiang-Bi; Wang, Ai-Hua; Hu, Le-Ning; Huang, Yuan; Li, Yang; He, Xun-Yang; Su, Yi-Rong

2014-03-01

32

The Influence of Pedology and Changes in Soil Moisture Status on Manganese Release from Upland Catchments: Soil  

E-print Network

The Influence of Pedology and Changes in Soil Moisture Status on Manganese Release from Upland /Accepted: 14 January 2007 # Springer Science + Business Media B.V. 2007 Abstract Manganese (Mn . Manganese . Mobilisation . Soil horizon . Soil water . Upland catchments 1 Introduction The trace metal

Heal, Kate

33

Accounting for variability in soil microbial communities of temperate upland grassland ecosystems  

Microsoft Academic Search

This study aimed to determine the factors which regulate soil microbial community organisation and function in temperate upland grassland ecosystems. Soil microbial biomass (Cmic), activity (respiration and potential carbon utilisation) and community structure (phospholipid fatty acid (PLFA) analysis, culturing and community level physiological profiles (CLPP) (Biolog®)) were measured across a gradient of three upland grassland types; Festuca–Agrostis–Galium grassland (unimproved grassland,

S. J. Grayston; G. S. Griffith; J. L. Mawdsley; C. D. Campbell; R. D. Bardgett

2001-01-01

34

Influence of water table level and soil properties on emissions of greenhouse gases from cultivated peat soil  

Microsoft Academic Search

A lysimeter method using undisturbed soil columns was used to investigate the effect of water table depth and soil properties on soil organic matter decomposition and greenhouse gas (GHG) emissions from cultivated peat soils. The study was carried out using cultivated organic soils from two locations in Sweden: Örke, a typical cultivated fen peat with low pH and high organic

Ö. Berglund; K. Berglund

2011-01-01

35

Effect of soil properties on peat erosion and suspended sediment delivery in drained peatlands  

NASA Astrophysics Data System (ADS)

from peat extraction areas is known to cause siltation of water courses and poor water quality. However, the main soil parameters affecting peat erosion and suspended sediment (SS) yields from different catchments are not well understood. This paper used peat properties (degree of humification, peat type, ash content, porosity, moisture content, bulk density, and shear strength) and novel erosion threshold measurements from intact soil cores to explain peat erodibility and spatial variations in SS concentrations (SSCs) and SS loads (SSLs) at 20 Finnish peat extraction sites. The erosion threshold measurements suggested that critical shear stresses for particle entrainment decrease with increasing degree of humification (von Post scale) and are significantly lower in well-decomposed peat than in slightly or moderately decomposed peat. Two critical shear stresses were obtained from moderately decomposed peat samples, indicating a degree of surface armoring by coarse peat fibers. Monitored long-term average SSC was highest at study sites with well-decomposed peat, while very fine-grained mineral subsoil explained some of the highest long-term SSC in areas where drainage ditches penetrated below the upper peat layer. Average SSL (kg d-1) at the study sites was best explained (R2 = 0.89) by average discharge and surface peat decomposition level. Overall, this study provides new knowledge on peat erosion and critical shear stresses that can be used in water conservation and sediment management practices for cutover peatlands and other similar land uses.

Tuukkanen, Tapio; Marttila, Hannu; Kløve, Bjørn

2014-04-01

36

Field portable XRF as a tool for the assessment of contaminated peat soils  

NASA Astrophysics Data System (ADS)

Upland blanket bogs in the UK have suffered severe erosion over the last millennium but there is evidence to show that this has increased in intensity in the last 250 years, coinciding with increased pressures on the land during the British Industrial Revolution. Upland peat soils in close proximity to urban and industrial areas can be contaminated with - and act as sinks for - high concentrations of atmospherically deposited lead. Atmospheric pollution has been shown to have had significant effects on blanket bog vegetation, the damage and removal of which makes the peat mass highly susceptible to erosion. Erosion of these soils has the potential to release lead into the fluvial system. Detailed quantification of lead concentrations across the surface of actively eroding peatlands is vital in order to understand lead storage and release in such environments. Previous attempts to quantify peatland lead pollution have been undertaken using the inventory approach. However, there can be significant within-site spatial heterogeneity in lead concentrations, highlighting the need for multiple samples to properly quantify lead storage. Lead concentrations in peat are traditionally derived through acid extraction followed by ICP-OES or AAS analyses, but these can be time consuming, expensive and destructive. By contrast, field portable x-ray fluorescence (FPXRF) analysers are relatively inexpensive, allow a large number of samples to be processed in a comparatively short time, giving a high level of detail with little disturbance to the surrounding area. FPXRF continues to gain acceptance in the study of metal contaminated soil but has not been used to conduct field surveys of contaminated peat soils due to their high moisture content. This study compares lead concentration data obtained in situ using a handheld Niton XL3t 900 XRF analyser with data derived from ex situ lab based analyses. In situ measurements were acquired across degraded and intact peatland sites in the Peak District, UK. Field samples were then dried, homogenised and analysed again using the FPXRF before subsequent acid digestion and analysis using ICP-OES. The moisture content of the samples was also determined and used to normalise the in situ field measurements. Good relationships were found between in situ and ex situ lead concentration data. When comparing in situ and ex situ derived FPXRF concentrations, linear regression analysis yielded R2 values of 0.86. This was improved significantly when in situ concentrations are normalised for moisture content (R2 = 0.92). A similar relationship was found between moisture corrected in situ results and ICP-OES derived values. These is also and excellent relationship between ex situ FPXRF and ICP-OES data (R2 = 0.99). This study reveals that FPXRF can provide an accurate, rapid and cost-effective means of assessing lead content in contaminated peat. The FPXRF analyser can be used to produce high quality data both in situ and ex situ, and shows promise as a tool for use in sediment source fingerprinting and understanding sediment dynamics in wet, organic systems.

Shuttleworth, Emma; Evans, Martin; Rothwell, James; Hutchinson, Simon

2013-04-01

37

Soil oxygen availability and biogeochemistry along rainfall and topographic gradients in upland wet tropical forest soils  

Microsoft Academic Search

We measured soil oxygen concentrations at 10 and 35 cm depths and indices of biogeochemical cycling in upland forest soils along a rainfall and elevation gradient (3500–5000 mm y-1; 350–1050 masl) and along topographic gradients (ridge to valley, ~150 m) in the Luquillo Experimental Forest, Puerto Rico. Along the rainfall gradient, soil O2 availability decreased significantly with increasing annual rainfall,

Whendee L. Silver; A. E. Lugo; M. Keller

1999-01-01

38

Behaviour of the Radionuclides in Peat Soils  

Microsoft Academic Search

On the basis of theoretical and experimental studies a method of assessment and prognosis of the radionuclides migration soils\\u000a has been created.\\u000a \\u000a Experimental methods for the determination of transfer characteristics and their assessment, and also the methods for prediction\\u000a of radionuclide migration in frozen grounds should provide a clear distinction between driving forces and fluxes of the convection\\u000a and diffusion

G. Brovka; I. Dedulya; E. Rovdan

39

Is the blocking of drainage channels in upland peats an effective means of reducing DOC loss at the catchment scale?  

NASA Astrophysics Data System (ADS)

Only 3% of the earths land surface is covered by peatland yet boreal and subarctic peatlands store approximately 15-30% of the World's soil carbon as peat (Limpens et al. 2008). In comparison British bogs store carbon equivalent to 20 years worth of national emissions. The loss of carbon from these areas in the form of dissolved organic carbon (DOC) is increasing and it is expected to have grown by up to 40% by 2018. Extensive drainage of UK peatlands has been associated with dehydration of the peat, an increase in water colour and a loss of carbon storage. It has been considered that the blocking of these drainage channels represents a means of peat restoration and a way of reducing DOC loss. This study aims to assess the effectiveness of this drain blocking at both an individual drain scale and at a larger catchment scale. Gibson et al. (2009) considered the effects of blocking at a solely individual drain scale finding that a 20% drop in DOC export was recorded post blocking however this decrease was due to a reduction in water yield rather than a reduction in DOC concentration with the concentration record showing no significant reduction. The effect of external parameters become more pronounced as the DOC record is examined at larger scales. The catchment is an open system and water chemistry will be influence by mixing with water from other sources. Also it is likely that at some point the drains will cut across slope leading to the flow of any highly coloured water down slope, bypassing the blockages, and entering the surface waters downstream. Degradation of DOC will occur naturally downstream due to the effects of light and microbial activity. There is, consequently, a need to examine the wider effects of drain blocking at a catchment scale to ensure that what is observed for one drain transfers to the whole catchment. A series of blocked and unblocked catchments were studied in Upper Teesdale, Northern England. Drain water samples were taken at least daily at nine localities. These sites were located such that individual drains could be monitored in the context of a larger catchment. Water table depth, flow and weather parameters were recorded along with the collection of runoff and soil water samples. A detailed sampling programme was undertaken in which a series of drains were studied in the 12 months prior to and post blocking. This approach has allowed the effects of blocking on the carbon budget, water balance and flow pathways to be considered. Results indicate that the blocking of zero order drainage channels leads to a decrease in DOC export on an individual drain scale. However, this is due to a reduction in water yield rather than concentration. Concentrations are seen to rise by a small yet statistically significant amount in blocked zero order streams. The effect at a larger scale is more complex. Annual export values in the unblocked control catchment show a rise from zero to first order streams indicating that water is being added to the system at this scale from external spatially variable sources. This pattern is also recognised in the blocked catchment. The DOC concentration record in blocked drains at this larger scale however indicated a reduction relative to the unblocked catchment. This reduction points to a change in flow pathways post blocking as highly coloured water re-navigates its way downstream. References: Gibson H, Worrall F, Burt TP, Adamson JK (2009) DOC budgets of drained peat catchments: implications for DOC production in peat soils, Hydrological Processes 23(13) 1901-1911 Limpens J (2008) Peatlands and the carbon cycle: from local processes to global implications- a synthesis, Biogeosciences 5 1475-1491

Turner, Kate; Worrall, Fred

2010-05-01

40

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

NASA Astrophysics Data System (ADS)

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.

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

41

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

PubMed

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

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

2014-01-01

42

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

PubMed Central

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

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

2014-01-01

43

DIVISION S-10--WETLAND SOILS Carbon Accumulation and Storage in Mineral Subsoil beneath Peat  

E-print Network

DIVISION S-10--WETLAND SOILS Carbon Accumulation and Storage in Mineral Subsoil beneath Peat Tim R subsoil (Turunen and Moore, 2003). TheyWe showed that sandy subsoils beneath peat near Ramsey Lake AND METHODS DOC under anoxic conditions. Study Area The soils were collected from near Ramsay Lake, upper

Moore, Tim

44

Soil CO2 production in upland tundra where permafrost is thawing Hanna Lee,1,2  

E-print Network

Soil CO2 production in upland tundra where permafrost is thawing Hanna Lee,1,2 Edward A. G. Schuur 2009; published 16 February 2010. [1] Permafrost soils store nearly half of global soil carbon (C), and therefore permafrost thawing could lead to large amounts of greenhouse gas emissions via decomposition

Wagner, Diane

45

Dynamic interactions between soil animals and microorganisms in upland grassland soils amended with sheep dung: a microcosm experiment  

Microsoft Academic Search

There is presently much discussion over factors regulating soil microbial processes in grazed grassland ecosystems. We examined the relative importance of dung and soil fauna, and their interactions on microbial biomass and activity in two contrasting upland grassland soils. We found that the presence of nematodes and Collembola was associated with significant (P<0.05) increases in microbial biomass in both soil

R. D. Bardgett; S. Keiller; R. Cook; A. S. Gilburn

1998-01-01

46

Peat soil composition as indicator of plants growth environment  

Microsoft Academic Search

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

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

2009-01-01

47

The contribution of dairy farming on peat soil to N and P loading of surface water  

Microsoft Academic Search

In agriculturally used peat land areas, surface water quality standards for nitrogen (N) and phosphorus (P) are frequently exceeded, but it is unclear to what extent agriculture is responsible for nutrient loading of the surface water. We quantified the contribution of different sources to the N and P loading of a ditch draining a grassland on peat soil (Terric Histosol)

C. L. van Beek; G. A. P. H. van den Eertwegh; F. H. van Schaik; G. L. Velthof; O. Oenema

2004-01-01

48

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

NASA Astrophysics Data System (ADS)

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

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

2010-05-01

49

Nitrogen mineralization and nitrification in upland and peatland forest soils in two Canadian Shield catchments  

Microsoft Academic Search

Net mineralization and nitrification in surface forest soils were measured in upland forest stands and valley peatlands using in situ soil incubations at two headwater catchments of Harp Lake, Ontario from July 1995 to October 1996. No difference in either net N mineralization or nitrification was observed between the two adjacent catchments despite differences in catchment N export. Annual rates

Kevin J. Devito; Cherie J. Westbrook; Sherry L. Schiff

1999-01-01

50

Analysing flow patterns in degraded peat soils using TiO2 dye  

NASA Astrophysics Data System (ADS)

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.

Liu, Haojie; Lennartz, Bernd

2014-05-01

51

MERCURY IN MUSHROOMS AND SOIL FROM THE WIELU?SKA UPLAND IN SOUTH-CENTRAL POLAND  

Microsoft Academic Search

Concentrations of mercury were determined in the fruiting bodies of 15 species of higher mushrooms and underlying soil substrate collected from Wielu?ska Upland in northern part of Sandomierska Valley in south-central Poland in 1995. A total of 197 samples of caps, 197 stalks, 30 whole fruiting bodies and 227 soil (0–10 cm layer) were analyzed. Mean mercury concentrations in soil substrate

Jerzy Falandysz; Leszek Bielawski; Masahide Kawano; Andrzej Brzostowski; Krzysztof Chudzy?ski

2002-01-01

52

Land Use Effect on Methane Oxidation and Its Kinetics in Tropical Upland Soils  

Microsoft Academic Search

Upland soil represents the important biological sink for atmospheric methane. In the tropics, one of the most remarkable changes in land use in the past decades is deforestation. It is estimated that deforestation rates in the tropic are as rapid as 2% yr-1. Such land use change may lead to loss of methane oxidation and thus may have implicated the

A. Chidthaisong; S. Vanitchang; N. W. Harvey; R. Conrad

2004-01-01

53

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

Microsoft Academic Search

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

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

1991-01-01

54

Spatial structure in soil chemical and microbiological properties in an upland grassland  

Microsoft Academic Search

We characterised the spatial structure of soil microbial communities in an unimproved grazed upland grassland in the Scottish Borders. A range of soil chemical parameters, cultivable microbes, protozoa, nematodes, phospholipid fatty acid (PLFA) profiles, community-level physiological profiles (CLPP), intra-radical arbuscular mycorrhizal community structure, and eubacterial, actinomycete, pseudomonad and ammonia-oxidiser 16S rRNA gene profiles, assessed by denaturing gradient gel electrophoresis (DGGE)

K. Ritz; J. W. McNicol; N. Nunan; S. Grayston; P. Millard; D. Atkinson; A. Gollotte; D. Habeshaw; B. Boag; C. D. Clegg; B. S. Griffiths; R. E. Wheatley; L. A. Glover; A. E. McCaig; J. I. Prosser

2004-01-01

55

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

Microsoft Academic Search

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, UO2, U(IV), Th, Am), in the soils of a small catchment in

E. Tipping

1996-01-01

56

Seasonal influences on fungal community structure in unimprovedand improved upland grassland soils  

SciTech Connect

Seasonal and management influences on the fungal communitystructure of two upland grassland soils were investigated. An upland sitecontaining both unimproved, floristically-diverse (U4a) and mesotrophic,improved (MG7b) grassland types was selected, and samples from bothgrassland types were taken at five times in one year. Soil fungalcommunity structure was assessed using fungal automated ribosomalintergenic spacer analysis (ARISA), a DNA-profiling approach. Grasslandmanagement regime was found to strongly affect fungal communitystructure, with fungal ARISA profiles from unimproved and improvedgrassland soils differing significantly. The number of fungal ribotypesfound was higher in unimproved than improved grassland soils, providingevidence that improvement may reduce the suitability of upland soil as ahabitat for specific groups of fungi. Seasonal influences on fungalcommunity structure were also noted, with samples taken in autumn(October) more correlated with change in ribotype profiles than samplesfrom otherseasons. However, seasonal variation did not obscure themeasurement of differences in fungal community structure that were due toagricultural improvement, with canonical correspondence analysis (CCA)indicating grassland type had a stronger influence on fungal profilesthan season.

Kennedy, Nabla; Brodie, Eoin; Connolly, John; Clipson, Nicholas

2006-07-01

57

Seasonal and management influences on bacterial community structure in an upland grassland soil.  

PubMed

Floristically diverse Nardo-Galion upland grasslands are common in Ireland and the UK and are valuable in agricultural, environmental and ecological terms. Under improvement (inputs of lime, fertiliser and re-seeding), they convert to mesotrophic grassland containing very few plant species. The effects of upland grassland improvement and seasonality on soil microbial communities were investigated at an upland site. Samples were taken at five times in one year in order to observe seasonal trends, and bacterial community structure was monitored using automated ribosomal intergenic spacer analysis (ARISA), a DNA-fingerprinting approach. Differences in soil chemistry and bacterial community structure between unimproved and improved grassland soils were noted. Season was also found to cause mild fluctuations in bacterial community structure, with soil samples from colder months (October and December) more correlated with change in ribotype profiles than samples from warmer months. However, for the majority of seasons clear differences in bacterial community structures from unimproved and improved soils could be seen, indicating seasonal influences did not obscure effects associated with improvement. PMID:16329952

Kennedy, Nabla M; Gleeson, Deirdre E; Connolly, John; Clipson, Nicholas J W

2005-08-01

58

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

PubMed Central

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

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

2013-01-01

59

Effects of Converting Secondary Forest to Oil Palm Plantation on Peat Soil Carbon and Nitrogen and other Soil Chemical Properties  

Microsoft Academic Search

Problem statement: Peatlands are natural sequesters of carbon and nitr ogen. Once they are disturbed the tendency to lose carbon and nitrogen to the environment is very high. This study investigated the effect of converting peat land for est into oil palm plantation on soil chemical properties with particular emphasis on carbon and n itrogen storage. Approach: Soil samples were

Makilan Muniandy; Osumanu Haruna Ahmed; Nik Muhamad Ab. Majid; Mohd Khanif Yusop

2009-01-01

60

Organic carbon transformations in high-Arctic peat soils: key functions and microorganisms  

PubMed Central

A substantial part of the Earths' soil organic carbon (SOC) is stored in Arctic permafrost peatlands, which represent large potential sources for increased emissions of the greenhouse gases CH4 and CO2 in a warming climate. The microbial communities and their genetic repertoire involved in the breakdown and mineralisation of SOC in these soils are, however, poorly understood. In this study, we applied a combined metagenomic and metatranscriptomic approach on two Arctic peat soils to investigate the identity and the gene pool of the microbiota driving the SOC degradation in the seasonally thawed active layers. A large and diverse set of genes encoding plant polymer-degrading enzymes was found, comparable to microbiotas from temperate and subtropical soils. This indicates that the metabolic potential for SOC degradation in Arctic peat is not different from that of other climatic zones. The majority of these genes were assigned to three bacterial phyla, Actinobacteria, Verrucomicrobia and Bacteroidetes. Anaerobic metabolic pathways and the fraction of methanogenic archaea increased with peat depth, evident for a gradual transition from aerobic to anaerobic lifestyles. A population of CH4-oxidising bacteria closely related to Methylobacter tundripaludum was the dominating active group of methanotrophs. Based on the in-depth characterisation of the microbes and their genes, we conclude that these Arctic peat soils will turn into CO2 sources owing to increased active layer depth and prolonged growing season. However, the extent of future CH4 emissions will critically depend on the response of the methanotrophic bacteria. PMID:22955232

Tveit, Alexander; Schwacke, Rainer; Svenning, Mette M; Urich, Tim

2013-01-01

61

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

PubMed Central

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

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

2012-01-01

62

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

E-print Network

Transport of lead and diesel fuel through a peat soil near Juneau, AK: a pilot study Julian Deissa potential of lead (Pb) and diesel range organics (DRO) in palustrine slope wetlands near Juneau, AK; Lead (Pb); Diesel range organic (DRO); Macropore; Rifle range; Wetland 0169-7722/$ - see front matter D

Walter, M.Todd

63

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

PubMed

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

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

2013-01-01

64

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

NASA Astrophysics Data System (ADS)

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.

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

2012-12-01

65

Effectiveness of Sesbania rostrata and Phaseolus calcaratus as green manure for upland rice grown in acidic soil  

Microsoft Academic Search

Two field experiments on green manuring were conducted under upland acidic soil (pH = 4.35) conditions with the following objectives: (1) to determine the influence of inoculation site, P fertilization, and liming on the biomass production, N content, N accumulation, and N availability of S. rostrata grown in an acidic soil, (2) to compare the effectiveness of S. rostrata, P.

I. J. Manguiat; P. W. Singleton; P. M. Rocamora; M. U. Calo; E. E. Taleon

1997-01-01

66

Draft Genome Sequence of Paenibacillus sp. Strain MSt1 with Broad Antimicrobial Activity, Isolated from Malaysian Tropical Peat Swamp Soil  

PubMed Central

We report the draft genome sequence of Paenibacillus sp. strain MSt1, which has broad-range antimicrobial activity, isolated from tropical peat swamp soil. Genes involved in antimicrobial biosynthesis are found to be present in this genome. PMID:25301658

Ong, Kuan Shion; Yule, Catherine M.; Gan, Han Ming; Lee, Sui Mae

2014-01-01

67

An easily installable groundwater lysimeter to determine water balance components and hydraulic properties of peat soils Hydrology and Earth System Sciences, 7(1), 2332 (2003) EGU  

E-print Network

properties of peat soils 23 Hydrology and Earth System Sciences, 7(1), 23­32 (2003) © EGU An easily Kai Schwaerzel1 and Heiko P. Bohl2 1 Institute of Ecology, Department of Soil Sciences and Soil installable groundwater lysimeter to determine water balance components and hydraulic properties of peat soils

Boyer, Edmond

68

[Nitrogen-fixing activity in peat soils from a raised bog].  

PubMed

The nitrogenase (acetylene reductase) activity in monolithic and minced peat samples was found to be low, no more than 0.014-0.022 mg N/(kg h). Incorporation of the 15N2 isotope into organic compounds of peat soil was from 2.71-8.13 mg N/kg over 15 days. The nitrogen-fixing activity was the highest in a 10-20 cm layer of soil and much lower in the upper (under green moss) and deeper (20-30 cm) layers. The addition of glucose to soil samples stimulated nitrogen fixation considerably after 18-26 h. The maximum nitrogenase activity (3.5-3.8 mg N/(kg h)) observed after 60-70 h coincided with the peak of respiratory activity. A repeated addition of glucose after its exhaustion increased nitrogenase activity without a lag period to 8.5 mg N/(kg h). Investigation of the effect of environmental factors (temperature, pH, aeration, and light intensity) on potential nitrogen-fixing activity in peat samples revealed that nitrogen fixation could proceed in a wide range of pH values (from 3.0 to 7.5) and temperatures (from 5 to 35 degrees C). The nitrogen-fixing bacteria belonging to different trophic groups were enumerated by using nitrogen-free media with pH values and mineralization levels close to those in situ. In samples of peat soil, diazotrophic methanol-utilizing bacteria prevailed (2.0-2.5 x 10(6) cells/g); the second largest group was facultatively anaerobic bacteria of the family Enterobacteriaceae. PMID:12698801

Kravchenko, I K; Doroshenko, E V

2003-01-01

69

Prediction of Soil Erosion from Uplands under Climate Change Scenarios in Korea  

NASA Astrophysics Data System (ADS)

Major impacts of climate change expect that soil erosion rate may increase during the 21st century. This study was conducted to assess the potential impacts of climate change on soil erosion by water in Korea. The soil loss was estimated for regions with the potential risk of soil erosion on a national scale. For computation, Universal soil loss equation (USLE) with rainfall and runoff erosivity factors (R), cover management factors (C), support practice factors (P) and revised USLE with soil erodibility factors (K) and topographic factors (LS) were used. RUSLE, the revised version of USLE, was modified for Korean conditions and re-evaluated to estimate the national-scale of soil loss based on the digital soil maps for Korea. The changes of precipitation for 2010 to 2090s were predicted under A1B scenarios made by National Institute of Meteorological Research in Korea. Future soil loss was predicted based on a change of R factor. As results, the predicted precipitations were increased by 6.7% for 2010 to 2030, 9.5% for 2040 to 2060s and 190% for 2070 to 2090s, respectively. The total soil loss from uplands in 2005 was estimated approximately 28?106 ton. Total soil losses were estimated as 31?106 ton in 2010 to 2030s, 31?106 ton in 2040 to 2060s and 33?106 ton in 2070 to 2090s, respectively. As precipitation increased by 17% in the end of 21st century, the total soil loss was increased by 12.9%. Overall, these results emphasize the significance of precipitation. However, it should be noted that when precipitation becomes insignificant, the results may turn out to be complex due to the large interaction among plant biomass, runoff and erosion. This may cause increase or decrease the overall erosion.

Kim, Min-Kyeong; Ko, Byong-Gu; Hur, Seung-Oh; Kim, Min-Young; Lee, Deog-Bae

2010-05-01

70

Temperature, water content and wet–dry cycle effects on DOC production and carbon mineralization in agricultural peat soils  

Microsoft Academic Search

Agricultural peat soils in the Sacramento-San Joaquin Delta, California have been identified as an important source of dissolved organic carbon (DOC) and trihalomethane precursors in waters exported for drinking. The objectives of this study were to examine the primary sources of DOC from soil profiles (surface vs. subsurface), factors (temperature, soil water content and wet–dry cycles) controlling DOC production, and

Alex T. Chow; Kenneth K. Tanji; Suduan Gao; Randy A. Dahlgren

2006-01-01

71

The xanthine oxidase activity in different of secondary transformed peat-moorsh soils  

NASA Astrophysics Data System (ADS)

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 investigation were located along Wysko? ditch. The following material was taken from four chosen sites marked as Zb?chy, Bridge, Shelterbelt and Hirudo in two layers: acrotelm (0-50 cm) and catotelm (50-100 cm). The object of this study was to characterize the biochemical properties by the determination of the xanthine oxidase activity in two layers (acrotelm and catotelm) of the four different peat-moorsh soils used as meadow. The xanthine oxidase activity was determined spectrophotometrically by measuring uric acid formation at ?max=290 nm with xanthine as substrate. In peat-moorsh soil the highest activities of xanthine oxidasewas observed in the Shelterbelt and whereas the lowest - in Zb?chy, Bridge and Hirudo. Activities of this enzyme in peat-moorsh soil ranged from 5.96 to 19.51 ?mol h-1g d.m soil. Increased activities of xanthine oxidase have been recorded on the depth 50-100 cm - catotelm (from 11.71 to 19.51 ?mol h-1g d.m soil) in comparison with the depth 0-50 cm - acrotelm (from 5.96 to 14.64 ?mol h-1g d.m soil). This work was supported by a grant No. N N305 3204 36 founded by Polish Ministry of Education.

Sty?a, Katarzyna; Wojciech Szajdak, Lech

2010-05-01

72

Impact of soil and groundwater heterogeneity on surface water chemistry in an upland catchment  

NASA Astrophysics Data System (ADS)

The interaction of precipitation with catchment soils is commonly assumed to be the dominant control on the composition and quality of the resulting surface waters. A hydrochemical investigation of a small granitic upland catchment (NE Scotland) was undertaken to study the link between the spatial distribution of soils and the heterogeneity of surface water chemistry. The approach involved division of the study area into subcatchments with a spatial range of 4-124 ha. Mean concentrations of stream water solutes showed considerable spatial variability across the catchment. Although links existed between surface water hydrochemistry and soil distribution, the dominant soil types on an area basis did not necessarily control subcatchment hydrochemistry. Solute fluxes showed more pronounced heterogeneity than that reflected by concentrations alone. Groundwater inputs to streams were implicated from calculations of water budgets and were characterised by elevated geochemical solute concentrations; this enhanced the hydrochemical heterogeneity attributed to surface soil drainage and hence highlighted the complexities of subsurface flow pathways. One small tributary lower in the catchment (3% of the total area) from a groundwater-dominated source was influential in controlling the overall outflow chemistry from the whole catchment. Generally, whilst hydrochemical modelling often considers such catchments as homogeneous units, advances in understanding the hydrochemical functioning of catchments will only be made when the full range of catchment water source compositions is accounted for. Such heterogeneity makes it difficult for management decisions based on spatially averaged data to adequately predict and protect against degradation in water quality.

Stutter, M. I.; Deeks, L. K.; Low, D.; Billett, M. F.

2006-03-01

73

Mineralization and microbial biomass formation in upland soil amended with some tropical plant residues at different temperatures  

Microsoft Academic Search

A model experiment was carried out at 15, 25, and 35°C to investigate the changes in microbial biomass and the pattern of mineralization in upland soil during 8 weeks following the addition of 8 organic materials including 6 tropical plant residues, ipil ipil (Leucaena leucocephala), azolla (Azolla pinnata), water hyacinth (Eichhornia crassipes), dhaincha (Sesbania rostrata), cowpea (Vigna unguiculata), and sunhemp

Abul Kalam Mohammad Azmal; Takuya Marumoto; Haruo Shindo; Masaya Nishiyama

1996-01-01

74

Correlation of Methane Production and Functional Gene Transcriptional Activity in a Peat Soil ?  

PubMed Central

The transcription dynamics of subunit A of the key gene in methanogenesis (methyl coenzyme M reductase; mcrA) was studied to evaluate the relationship between process rate (methanogenesis) and gene transcription dynamics in a peat soil ecosystem. Soil methanogen process rates were determined during incubation of peat slurries at temperatures from 4 to 37°C, and real-time quantitative PCR was applied to quantify the abundances of mcrA genes and transcripts; corresponding transcriptional dynamics were calculated from mcrA transcript/gene ratios. Internal standards suggested unbiased recovery of mRNA abundances in comparison to DNA levels. In comparison to those in pure-culture studies, mcrA transcript/gene ratios indicated underestimation by 1 order of magnitude, possibly due to high proportions of inactive or dead methanogens. Methane production rates were temperature dependent, with maxima at 25°C, but changes in abundance and transcription of the mcrA gene showed no correlation with temperature. However, mcrA transcript/gene ratios correlated weakly (regression coefficient = 0.76) with rates of methanogenesis. Methanogen process rates increased over 3 orders of magnitude, while the corresponding maximum transcript/gene ratio increase was only 18-fold. mcrA transcript dynamics suggested steady-state expression in peat soil after incubation for 24 and 48 h, similar to that in stationary-phase cultures. mcrA transcript/gene ratios are therefore potential in situ indicators of methanogen process rate changes in complex soil systems. PMID:19749064

Freitag, Thomas E.; Prosser, James I.

2009-01-01

75

Changes in soil fungal:bacterial biomass ratios following reductions in the intensity of management of an upland grassland  

Microsoft Academic Search

In this study we examined the effect on soil fungal:bacterial biomass ratios of withholding fertiliser, lime, and sheep-grazing from reseeded upland grassland. The cessation of fertiliser applications on limed and grazed grassland resulted in a reduction in soil pH from 5.4 to 5.1. The cessation of fertiliser applications and liming on grazed grassland resulted in a fall in pH from

Richard D. Bardgett; Philip J. Hobbs; Åsa Frostegård

1996-01-01

76

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

SciTech Connect

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.

Riha, B

2005-10-31

77

Permafrost controls on soil C storage and turnover in upland black spruce ecosystems of interior Alaska  

NASA Astrophysics Data System (ADS)

Permafrost soils in northern latitudes have functioned as important reservoirs for organic carbon (OC) since the last glacial maximum. In particular, the formation of permafrost through syngenetic processes (e.g. aeolian loess deposition) allows for high rates of OC burial and stabilization. Recent warming at northern latitudes has resulted in warming and thawing of permafrost in many regions, which may mobilize OC stocks from deep soil reservoirs via decomposition, leaching or erosion. Furthermore, in the boreal region, increased wildfire frequency and severity may promote rapid permafrost thaw and soil OC loss from forested ecosystems. Release of OC stocks from permafrost as carbon dioxide or methane may function as a strong positive feedback to atmospheric warming. Here, we examine patterns of OC storage in active layer and permafrost soils across a fire chronosequence of upland black spruce stands near Hess Creek, interior Alaska. Our research objective was to evaluate how post-fire changes in organic horizon thickness and consequently, changes in active layer thickness, influence rates of OC turnover in deep mineral soil. We used a finite-difference numerical model (GIPL2) to simulate permafrost dynamics and a steady-state radiocarbon model to estimate carbon turnover. To calibrate the permafrost model, we monitored soil temperature, soil moisture, snow depth, and active layer thickness at four sites across the fire chronosequence. To evaluate soil carbon dynamics, we measured OC stocks and radiocarbon inventories from zero to two meters below the ground surface across the chronosequence. Preliminary results from field observations and model runs indicate that active layer thickness was closely linked to fire severity, as reflected by organic horizon thickness. Total carbon storage to two meters averaged 35 ± 6 kg m-2 across the chronosequence, with between 42 and 67 % of these stocks below the permafrost table. Radiocarbon ages of soil OC at two meters ranged from 20,000 to 28,000 years before present, and generally increased with depth. Input rates of OC to surface organic horizons (via moss net primary productivity and litterfall) and to deep mineral soil (via charcoal, dissolved organics and roots) were similar, collectively averaging 0.010 kg C m-2 y-1. However, decomposition constants were an order of magnitude different between surface organic and deep mineral soils, averaging 0.010 and 0.001 yr-1 respectively. Together, these field observations and modeling approaches will allow us to evaluate the effects of future fire and climate conditions on permafrost degradation and carbon loss from northern soils.

O'Donnell, J. A.; Harden, J. W.; Romanovsky, V. E.; Kanevskiy, M. Z.; Jorgenson, T.; Xu, X.; Ewing, S. A.; McGuire, D.; Shur, Y.

2009-12-01

78

The influence of different types of grassland on soil quality in upland areas of Czech Republic.  

PubMed

The diversity of grassland in upland areas of Czech Republic was studied on selected soil characteristics of these biotopes. In the first phase, 44 soil characteristics were studied and mutual correlations were found between many of them. In the following phase characteristics were chosen which correlated most with other soil characteristics and, at the same time, were easy to evaluate in practise. A great number of correlations were also evidenced between many soil characteristics and the content of humus and nitrogen, which are closely linked to organic matter in soil. In studying these characteristics on selected areas with different types of grassland and consequential cluster analysis and further evaluation, the grassland plots were divided into three groups, from newly established vegetation to species-rich communities. Non-parametric analysis was carried out on the results and a statistically significant difference was proved between the species rich and poorvegetation and carbon and nitrogen content of the soil. Slightly different humus quality (higher amount of HA) was also found under richer vegetation. These results show that at 0-20 cm layer, 58.9 tonnes of carbon ha?¹ was measured under species-poor pastureland and 106.1 tonnes of carbon ha under species-rich vegetation. The results showed that besides supporting species diversity, the described quality change can also be important for carbon sequestration. The difference of about 40-50 tonnes of carbon ha and converting 10% of grassland in the Czech Republic to species-rich vegetation would mean sequestration of about 3.9 Mt carbon. If only agroenvironmentally subsidized areas are converted, carbon sequestration in such vegetation could amountto 1.7 Mt. PMID:24812999

Sarapatka, B; Cizkova, S

2014-05-01

79

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

NASA Astrophysics Data System (ADS)

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.

Comas, Xavier; Wright, William

2014-08-01

80

Technical Note: Development of an automated lysimeter for the calculation of peat soil actual evapotranspiration  

NASA Astrophysics Data System (ADS)

A limited number of publications in the literature deal with the measurement of actual evapotranspiration (AET) from a peat soil. AET is an important parameter in the description of water pathways of an ecosystem. In peatlands, where the water table is near the surface and the vegetation is composed of nonvascular plants without stomatal resistance, the AET measurement represents a challenge. This paper discusses the development of an automated lysimeter installed between 12 and 27 July 2010, at a 11-ha bog site, Pont-Rouge (42 km west of Quebec City, Canada). This system was made of an isolated block of peat, maintained at the same water level as the surrounding water table by a system of submersible pressure transmitters and pumps. The change in water level in millimetres in the isolated block of peat was used to calculate the water lost through evapotranspiration (ET) while accounting the precipitation. The rates of AET were calculated for each day of the study period. Temperature fluctuated between 17.2 and 23.3 °C and total rainfall was 43.76 mm. AET rates from 0.6 to 6.9 mm day-1 were recorded, with a ?AET/?P ratio of 1.38. The estimated potential ET (PET) resulting from Thornthwaite's semi-empirical formula suggested values between 2.8 and 3.9 mm day-1. The average AET/PET ratio was 1.13. According to the literature, the results obtained are plausible. This system, relatively inexpensive and simple to install, may eventually be used to calculate AET on peaty soils in the years to come.

Proulx-McInnis, S.; St-Hilaire, A.; Rousseau, A. N.; Jutras, S.; Carrer, G.; Levrel, G.

2011-05-01

81

Potential of Sphagnum peat for improving soil organic matter, water holding capacity, bulk density and potato yield in a sandy soil  

Microsoft Academic Search

Low soil organic matter content and limited soil water holding are the major natural constraint of dryland cropping on sandy soils in the Quebec boreal regions. We conducted a 3-yr (1994–1996) study in a boreal sandy soil, Ferro-Humic Podzol (Spodosols), to determine the potential of Sphagnum peat for improving soil organic matter (SOM), water holding capacity, bulk density (BD), plant

Hong Li; Léon E. Parent; Antoine Karam; Catherine Tremblay

2004-01-01

82

Plant soil interactions alter carbon cycling in an upland grassland soil  

PubMed Central

Soil carbon (C) storage is dependent upon the complex dynamics of fresh and native organic matter cycling, which are regulated by plant and soil-microbial activities. A fundamental challenge exists to link microbial biodiversity with plant-soil C cycling processes to elucidate the underlying mechanisms regulating soil carbon. To address this, we contrasted vegetated grassland soils with bare soils, which had been plant-free for 3 years, using stable isotope (13C) labeled substrate assays and molecular analyses of bacterial communities. Vegetated soils had higher C and N contents, biomass, and substrate-specific respiration rates. Conversely, following substrate addition unlabeled, native soil C cycling was accelerated in bare soil and retarded in vegetated soil; indicative of differential priming effects. Functional differences were reflected in bacterial biodiversity with Alphaproteobacteria and Acidobacteria dominating vegetated and bare soils, respectively. Significant isotopic enrichment of soil RNA was found after substrate addition and rates varied according to substrate type. However, assimilation was independent of plant presence which, in contrast to large differences in 13CO2 respiration rates, indicated greater substrate C use efficiency in bare, Acidobacteria-dominated soils. Stable isotope probing (SIP) revealed most community members had utilized substrates with little evidence for competitive outgrowth of sub-populations. Our findings support theories on how plant-mediated soil resource availability affects the turnover of different pools of soil carbon, and we further identify a potential role of soil microbial biodiversity. Specifically we conclude that emerging theories on the life histories of dominant soil taxa can be invoked to explain changes in soil carbon cycling linked to resource availability, and that there is a strong case for considering microbial biodiversity in future studies investigating the turnover of different pools of soil carbon. PMID:24058360

Thomson, Bruce C.; Ostle, Nick J.; McNamara, Niall P.; Oakley, Simon; Whiteley, Andrew S.; Bailey, Mark J.; Griffiths, Robert I.

2013-01-01

83

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

PubMed

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

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

1989-01-01

84

The influence of aeration and temperature on the structure of bacterial complexes in high-moor peat soil  

NASA Astrophysics Data System (ADS)

The number and taxonomic structure of the heterotrophic block of aerobic and facultative anaerobic bacteria were studied in monoliths from a high-moor peat (stored at room temperature and in a refrigerator) and in the peat horizons mixed in laboratory vessels. The monitoring lasted for a year. In the T0 horizon, spirilla predominated at room and low temperatures; in the T1 and T2 horizons, bacilli were the dominants. The continuous mixing of the peat layers increased the oxygen concentration and the peat decomposition; hence, the shares of actinomycetes and bacilli (bacteria of the hydrolytic complex) increased. In the peat studied, the bacilli were in the active state; i.e., vegetative cells predominated, whose amount ranged from 65 to 90%. The representatives of the main species of bacilli (the facultative anaerobic forms prevailed) hydrolyzed starch, pectin, and carboxymethylcellulose. Thus, precisely sporiferous bacteria can actively participate in the decomposition of plant polysaccharides in high-moor peat soils that are characterized by low temperatures and an oxygen deficit. The development of actinomycetes is inhibited by low temperatures; they can develop only under elevated temperature and better aeration.

Kukharenko, O. S.; Pavlova, N. S.; Dobrovol'Skaya, T. G.; Golovchenko, A. V.; Pochatkova, T. N.; Zenova, G. M.; Zvyagintsev, D. G.

2010-05-01

85

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...

86

Heavy metals uptake from contaminated soils as affected by peat, lime, and chelates  

SciTech Connect

Heavy metal contamination of soils may reduce yields as well as the suitability for consumption of crop growth (Keeney et al., Leeper). In an effort to find possible ways to counter this danger, the effect of lime, chelating agents, and peat applied to Zn-, Cu- and Pb-contaminated soils on the uptake of metal ions were studied. Pot experiments with barley (Hordeum vulgare L.), perennial ryegrass (Lolium perenne) and Italian ryegrass (Lolium multiflorum) plants and soils, humic podzols (haplohumads) contaminated with Zn (3030 mg kg/sup -1/) and with Pb, Zn and Cu (110, 630, and 40 mg kg/sup -//sub 1/, respectively) were carried out. The concentration of the acid extracts of soils and plants were determined with the aid of the simultaneous direct reading spectrograph and atomic absorption. In all cases, raising the pH of the soil by liming appeared to be the most efficient method for reducing plant absorption of toxic micronutrients and heavy metals. However, the uptake of Fe and Mn was more markedly dependent on pH than that of Zn and Cu.

Albasel, N.; Cottenie, A.

1985-01-01

87

Two dimensional hydrological simulation in elastic swelling/shrinking peat soils  

NASA Astrophysics Data System (ADS)

Peatlands respond to natural hydrologic cycles of precipitation and evapotranspiration with reversible deformations due to variations of water content in both the unsaturated and saturated zone. This phenomenon results in short-term vertical displacements of the soil surface that superimpose to the irreversible long-term subsidence naturally occurring in drained cropped peatlands because of bio-oxidation of the organic matter. The yearly sinking rates due to the irreversible process are usually comparable with the short-term deformation (swelling/shrinkage) and the latter must be evaluated to achieve a thorough understanding of the whole phenomenon. A mathematical model describing swelling/shrinkage dynamics in peat soils under unsaturated conditions has been derived from simple physical considerations, and validated by comparison with laboratory shrinkage data. The two-parameter model relates together the void and moisture ratios of the soil. This approach is implemented in a subsurface flow model describing variably saturated porous media flow (Richards' equation), by means of an appropriate modification of the general storage term. The contribution of the saturated zone to total deformation is considered by using information from the elastic storage coefficient. Simulations have been carried out for a drained cropped peatland south of the Venice Lagoon (Italy), for which a large data set of hydrological and deformation measurements has been collected since the end of 2001. The considered domain is representative of a field section bounded by ditches, subject to rainfall and evapotranspiration. The comparison between simulated and measured quantities demonstrates the capability of the model to accurately reproduce both the hydrological and deformation dynamics of peat, with values of the relevant parameters that are in good agreement with the literature.

Camporese, M.; Ferraris, S.; Paniconi, C.; Putti, M.; Salandin, P.; Teatini, P.

2005-12-01

88

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...

89

Temporal variations in soil–atmosphere methane exchange after fire in a peat swamp forest in West Siberia  

Microsoft Academic Search

Temporal variations in methane (CH4) exchange between the soil and the atmosphere during a period of 3 years after a forest fire were estimated by combining field measurements of CH4 flux with an analysis of satellite images. The study area was located in a boreal peat swamp forest in the West Siberian plain that experienced a severe fire in the summer

Tomoko Nakano; Wataru Takeuchi; Gen Inoue; Masami Fukuda; Yoshifumi Yasuoka

2006-01-01

90

Effects of temperature on microbial C metabolism in peat and mineral soil  

NASA Astrophysics Data System (ADS)

Microbial metabolism, the main mechanism responsible for soil CO2 emissions, plays an important role in the global C cycle. Increased temperature generally stimulates decomposition and respiration, indicative of increased microbial C metabolism and possibly greater energy demand by microbes for growth and maintenance. Changes in microbial metabolism with temperature may manifest differently in microbial communities from soils with different C availability because it is generally expected that when more organic C is present, carbon use efficiency (CUE) will be lower and more CO2 will be released per unit C assimilated by microbes than when less C substrate is available. In this study we examined the effect of temperature on C processing in peat and mineral soil from the Marcel Experimental Forest in Minnesota. Samples were incubated for 7 days at 5, 10, 15, and 20°C. We used position-specific 13C-labeled tracers to model C flux through the central C metabolic network (i.e. glycolysis, pentose phosphate pathway, and the citric acid cycle) and to asses the CUE of microbial communities. We also measured total CO2 production and microbial biomass, and we calculated the metabolic quotient (qCO2), which is the rate of CO2, respired per unit of microbial biomass. We found that temperature and soil type did not affect CUE and patterns of C flow through the central C metabolic network. Increased temperature stimulated respiration and decreased qCO2 in peat more than the mineral soil. These results suggest temperature affects rate of C cycling, but does not alter the relative demand for energy production and biosynthesis per unit substrate-C. This implies, in contrast to expectations that at higher temperatures more substrate will be used to offset greater demand for maintenance energy, warmer temperatures will not alter the balance of growth and maintenance energy by soil microbes. Moreover, substrate availability did not result in ';wasteful' C use, but increased C cycling rates. These findings may simplify the modeling of soil respiration with climatic warming.

Hagerty, S.; Dijkstra, P.; Miller, E.; Schwartz, E.; KOCH, G. W.; Hungate, B. A.

2013-12-01

91

Respiration of soil and ground vegetation of a peat bog in southern taiga under drought stress  

NASA Astrophysics Data System (ADS)

Respiration of peat and ground vegetation (mostly sphagnum mosses) was measured by CO2 analyser LI-6400 in late August 2002 in the peat bog (Central Forest Nature Reserve, 560N, 330E, Tver region, Russia). The whole summer 2002 in the region was characterized by hot and dry weather, thus obtained data correspond to the extreme drought stress. Measurements were carried out on the 16 stationary points along the transect crossing the mire along the altitude gradient and presenting the whole range of vegetation complexes diversity: margin lag with the spruce stand and eutrophic and mesotrophic conditions; typical oligotrophic lag with pine stand and dwarf shrubs, tall sedges mesotrophic lawn, not forested hummock-hollow complex, forested hummock-hollow complex, the dwarf pine communities of different structure and at last the type of minerotrophic margin with meadow vegetation. As a “zero-point” the spruce forest on the land was appointed as the measurement point. The transect under study is the object of the long-term observations on the ground vegetation and groundwater parameters, which were related to obtained respiration values. The measured mean values of ground respiration were 4.9, 6.8, 7.5, 4.8, 3.9 and 3.7 mkmol m-2s-1 for spruce stand (bare soil), paludified spruce stand, pine mire margin, dwarf pine communities oligotrophic and minerotrophic part of the mire, respectively. Within the open peat bog hummock-hollow complex significantly higher respiration was observed for hummocks comparatively to the hollows: 6.6 and 4.2 mkmol m-2s-1, correspondingly. Significant correlation of ground respiration to the groundwater level and temperature difference between peat and air was observed. The study was carried out within the framework of international project TCOS. The data on the spatial variation of dark respiration depending on the vegetation structure and groundwater regime is considered as a background for the further functional patterns for the virgin mire ecosystems of the Russian Plain.

Tatarinov, F.; Minaeva, T.; Kurbatova, Yu.; Rusanovitch, N.

2003-04-01

92

Heavy metal contamination from historic mining in upland soil and estuarine sediments of Egypt Bay, Maine, USA  

NASA Astrophysics Data System (ADS)

Concentrations of Cd, Cu, Pb and Zn in sediments of Egypt Bay in Hancock County, Maine, are elevated above background levels. The source of the contamination is Cu mining that occurred in the uplands adjacent to Egypt Stream between 1877 and 1885. Egypt Stream is a tributary to Egypt Bay. Egypt Bay is part of the Taunton Bay estuary system. The Hagan Mine was one of the mines extracting metals from the sulfide deposits in Downeast Maine north of Penobscot Bay. Metal concentrations were determined using ICP-AES after sample digestion with nitric acid. Soil collected from the coarse textured mine tailings pile contained elevated concentrations of Cd, Cu, Pb and Zn, but the majority of the surface soils at the Hagan Mine site were not contaminated. Estuary sediments from the surface to 100 cm depth were collected in four locations within Egypt Bay. Below 40 cm, metal concentrations in sediments were similar to those in uncontaminated upland soils. Metal concentrations in the estuary sediments between the surface and 26 cm were above background levels. According to 210Pb dating, the sediment at 26-34 cm depth was likely to have been deposited at the time the historic mines were in operation. Concentrations of Cd, Cu, Pb, and Zn in sediment from the 32-34 cm depth interval are similar to concentrations in the upland soil sample from the mine tailings pile. Elevated Pb concentrations in sediments from the surface to 24 cm are from atmospheric Pb deposition from anthropogenic sources. Sediment in the top 10 cm of the estuary has been mixed both by the polychaete worm Nereis virens and by those harvesting the worms for sale as fish bait.

Osher, L. J.; Leclerc, L.; Wiersma, G. B.; Hess, C. T.; Guiseppe, V. E.

2006-10-01

93

Farmers' knowledge of soils in relation to cropping practices: A case study of farmers in upland rice based slash-and-burn  

E-print Network

rice based slash-and-burn systems of northern Laos Kazuki Saito a,, Bruce Linquist b , Bounthanh of burn. Glutinous rice, their staple food, tended to be planted on good soils, while non-glutinous rice, had higher pH, total N, total C and CEC levels than the other color soils. Also, upland rice yields

van Kessel, Chris

94

Influence of oil and stratal water contamination on the ash composition of oligotrophic peat soils in the oil-production area (the Ob' region)  

NASA Astrophysics Data System (ADS)

The mineral contamination of peat soils in the oil-production area differs considerably in the places of oil or stratal water spills. The time elapsed since the spill occurred is also an important factor of the changes in the chemical composition of the peat ash. The ash content rises drastically in the oil-contaminated peat, and the peat ash becomes rich in heavy metals (Mn, Ni, and Sr) and lanthanides (La and Ce). The content of K and Fe decreases, and that of P, S, Mg, Ca, Ni, and Pb increases with time at the site of old oil contamination. In the course of the self-rehabilitation of oil-contaminated peat, the content of Cl decreases more intensely than that of the heavier halogen Br. The ash content rises to a lesser extent in the peat contaminated with stratal water. The ash of the salinized peat is enriched in heavy alkaline-earth elements, i.e., Ba and Sr. Although most of the elements are leached with time, the content of Ba and Sr still remains 4-6 times higher than the background one even after long-term (more than 10 years) leaching. The concentrations of halogens rise considerably in the salinized peat, that of Cl in the peat ash decreases by 10 times, and the content of Ba virtually remains the same.

Vodyanitskii, Yu. N.; Avetov, N. A.; Savichev, A. T.; Trofimov, S. Ya.; Shishkonakova, E. A.

2013-10-01

95

Fe–Al–organic Colloids Control of Trace Elements in Peat Soil Solutions: Results of Ultrafiltration and Dialysis  

Microsoft Academic Search

Size fractionation of ~40 major and trace elements (TE) in peat soil solutions from the Tverskaya region (Russia) has been\\u000a studied using frontal filtration and ultrafiltration through a progressively decreasing pore size (5, 2.5, 0.22 ?m, 100, 10,\\u000a 5, and 1 kD) and in situ dialysis through 6–8 and 1 kD membranes with subsequent analysis by ICP-MS. In (ultra) filter-passed

O. S. Pokrovsky; B. Dupré; J. Schott

2005-01-01

96

The effect of grassland utilisation on physicochemical properties of peat-muck soils and species composition of sward  

Microsoft Academic Search

The aim of these studies was to estimate the influence of utilisation or its lack on the changes of physicochemical properties of peat-muck soils as well as on the species composition of sward. Studies were carried out on the peatland complex located in the Pojezierze ??czy?sko-W?odawskie (Lake District), in south-eastern Poland. This complex spreads over a wide area on both

M. Kulik; R. Bary?a; M. Ward

97

Isolation and characterization of nitrogen-fixing bacteria of the genus Azospirillum from the soil of a Sphagnum peat bog  

Microsoft Academic Search

he presence of nitrogen-fixing bacteria of the genus Azospirillum in the soils of acidic raised Sphagnum bogs is revealed for the first time. Three Azospirillum strains, B2, B21, and B22, were isolated as a component of methane-oxidizing enrichment cultures, whereas attempts to isolate\\u000a them directly from peat samples have failed. The results of comparative analysis of the nucleotide sequences of

E. V. Doroshenko; E. S. Boulygina; E. M. Spiridonova; T. P. Tourova; I. K. Kravchenko

2007-01-01

98

Decomposition activity of peat soils in geogenous mires in Sasakami, central Japan  

Microsoft Academic Search

Decomposition rates of peat and cellulose, and oxygen consumption rates were studied in three minerotrophic peat mires in Sasakami, central Japan. These mires had differences in topography, pedology and hydrology. Two dominant vegetation types in each mire, a Sphagnum palustre–S. cuspidatum community and a Rhynchospora fauriei community, were selected as the decomposition study sites. The objective of this study was

Akira Haraguchi; Chiaki Hasegawa; Akiko Hirayama; Hisaya Kojima

2003-01-01

99

Please cite this article in press as: Dunne, E.J., et al., Soil phosphorus flux from emergent marsh wetlands and surrounding grazed pasture uplands. Ecol. Eng. (2010), doi:10.1016/j.ecoleng.2010.06.018  

E-print Network

.06.018 ARTICLE IN PRESS GModel ECOENG-1703; No.of Pages9 Ecological Engineering xxx (2010) xxx­xxx Contents lists 2010 Available online xxx Keywords: Phosphorus Soil Release Flux Wetlands Uplands a b s t r a c water. Our study initially characterized wetland and surrounding upland soils prior to flooding. Deep

Florida, University of

100

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

SciTech Connect

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.

Parsekian, Andrew D. [Rutgers University; Slater, Lee [Rutgers University; Ntarlagiannis, Dimitrios [Rutgers University; Nolan, James [Rutgers University; Sebestyen, Stephen D [USDA Forest Service, Grand Rapids, MN; Kolka, Randall K [USDA Forest Service, Grand Rapids, MN; Hanson, Paul J [ORNL

2012-01-01

101

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)

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.

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

2012-04-01

102

Identification and characterization of lipolytic enzymes from a peat-swamp forest soil metagenome.  

PubMed

In this work, a metagenomic library was generated from peat-swamp forest soil obtained from Narathiwat Province, Thailand. From a fosmid library of approximately 15,000 clones, six independent clones were found to possess lipolytic activity at acidic pH. Analysis of pyrosequencing data revealed six ORFs, which exhibited 34-71% protein similarity to known lipases/esterases. A fosmid clone, designated LP8, which demonstrated the highest level of lipolytic activity under acidic conditions and demonstrated extracellular activity, was subsequently subcloned and sequenced. The full-length lipase/esterase gene, estPS2, was identified. Its deduced amino acid was closely related to a lipolytic enzyme of an uncultured bacterium, and contained the highly conserved motif of a hormone-sensitive family IV lipase. The EstPS2 enzyme exhibited highest activity toward p-nitrophenyl butyrate (C?) at 37 °C at pH 5, indicating that it was an esterase with activity and secretion characteristics suitable for commercial development. PMID:20834152

Bunterngsook, Benjarat; Kanokratana, Pattanop; Thongaram, Taksawan; Tanapongpipat, Sutipa; Uengwetwanit, Tanaporn; Rachdawong, Sansanalak; Vichitsoonthonkul, Taweerat; Eurwilaichitr, Lily

2010-01-01

103

A coupled molecular and field-based approach to study microbial controls on methane flux in upland soils  

NASA Astrophysics Data System (ADS)

Predicting the responses of ecosystems to global change depends, in part, on understanding how soil microbial communities respond to external controls. To address this question, we are studying a relatively simple biogeochemical process: methane consumption in upland (i.e., well-drained, oxic) soils. In this process, methane molecules diffuse from the atmosphere into the soil, where they are consumed by methanotrophic bacteria. Because of the simplicity of this process, we have been able to develop a reaction-diffusion model that allows us to directly quantify methanotroph activity in situ from chamber-based measures of flux and diffusivity. Moreover, because the bacteria that oxidize methane come from a phylogenetically cohesive group, we can use molecular tools to quantify the size of methanotroph community and determine its species composition. Our application of these approaches on the Shortgrass Steppe Long-Term Ecological Research (SGS LTER) site in northeastern Colorado has revealed strong temporal and spatial patterns in methane uptake rates that are driven primarily by methanotroph activity, and very little by soil diffusivity. The temporal patterns in methanotroph activity follow seasonal changes in soil temperature and water content, with sharp reductions in activity associated with hot, dry conditions. Spatial patterns in activity follow differences in soil texture, with sandier soils expressing a greater range of methanotroph activity than clay soils. Although methanotroph abundances did not vary across soil types, the phylogenetic structure of the methanotroph communities differed significantly between clay and sand soil types. In addition, we found that the majority of methanotrophs were not the usual Type I or Type II, but instead were of the JR2 and JR3 types previously found only in a dry California grassland by Horz et al. AEM (2005). Together, these observations suggest that the species composition of methanotroph communities reflects changes in the physical environment. Given the potential for specialization among methanotrophs (e.g., for desiccation tolerance, or for methane affinity), we anticipate that the specific phylogenetic and physiological characteristics of methane oxidizer communities will modulate the responses of upland methane fluxes to climate change.

Judd, C. R.; von Fischer, J. C.; Fierer, N.

2007-12-01

104

Vertical transfer of {sup 137}Cs in peat soils fallen out as a consequence of the Chernobyl accident  

SciTech Connect

On the basis of measurements of the specific radioactivity of soil specimens sampled with a small step along their deposition, depth profiles are plotted for the curves of the vertical change in {sup 137}Cs in peat soils not treated since the Chernobyl accident. A theoretical analysis is provided for the plotted profiles that shows that the vertical transfer of {sup 137}Cs in these soils is described adequately within the framework of a model that accounts for the processes of diffusion and convection of the radionuclide in the soil solution and its sorption by the solid phase of the soil. The parameters of the model are determined and a prediction is given for the migration character of {sup 137}Cs.

Olekhnovich, N.M.; Makovetskii, G.I.; Galyas, A.I. [Inst. of Solid State Physics, Minsk (Belarus)] [and others

1995-08-01

105

Coevolution of topography, soils, and vegetation in upland landscapes: Using cinder cones to elucidate ecohydrogeomorphic feedback mechanisms  

NASA Astrophysics Data System (ADS)

The study of landscape evolution in upland environments requires analysis of complex interactions among topography, soil development, and vegetation cover under changing climatic conditions. Earth surface scientists lack a comprehensive understanding of these interactions in part due to their interdisciplinary nature, our limited ability to reconstruct the progression of landscape states through time, and the limited spatially-distributed data available for paleoclimate conditions. In this study, we investigate the interactions and feedbacks among topography, soil development, and vegetation cover in upland environments using remote sensing, geochemistry, and numerical modeling. We focus on quantifying the evolution of late Quaternary cinder cones within several volcanic fields, spanning a range of climates, as a function of age and microclimate, which varies with elevation and slope aspect. Cinder cones are excellent natural laboratories for studying the evolution of upland landscapes because they begin their evolution at a known time in the past (i.e. many cinder cones have been radiometrically dated) and because they often have unusually uniform initial conditions (i.e. they form close to the angle of repose and are comprised of well-sorted volcaniclastic parent materials). As such, cinder cones of different ages with similar size and climatic history can provide an approximate time progression illustrating how a dated hillslope has evolved over geologic time scales. Data suggest that rates of soil development and fluvial erosion are low on younger cones, which have surfaces consisting mostly of permeable cinders, but increase significantly after eolian deposits reduce the permeability of the cone surface. Further, data demonstrate that microclimatic differences between north and south facing slopes lead to systematic variations in biomass. Additionally, north-facing slopes on cinder cones are found to be steeper than corresponding south-facing slopes. The observed asymmetries in hillslope morphology are not present initially, but appear to develop over time as a result of differences in post-emplacement processes that may be attributed to aspect-induced microclimatic effects on long-term sediment transport rates. Results provide additional constraints on the timing and magnitude of feedback mechanisms among topography, biomass, and soil development as well as improve our understanding of cinder cone evolution within different climates.

McGuire, L.; Pelletier, J. D.; Rasmussen, C.

2013-12-01

106

Glomus mosseae enhances root growth and Cu and Pb acquisition of upland rice (Oryza sativa L.) in contaminated soils.  

PubMed

A pot culture experiment was carried out to investigate the roles of Glomus mosseae in Cu and Pb acquisition by upland rice (Oryza sativa L.) and the interactions between Cu and Pb. The soil was treated with three Cu levels (0, 100 and 200 mg kg(-1)) and three Pb levels (0, 300, and 600 mg kg(-1)). All treatments were designed with (+M) or without (-M) G. mosseae inoculation in a randomized block design. The addition of Cu and Pb significantly decreased root mycorrhizal colonization. Compared with -M, +M significantly increased root biomass in almost all treatments, and also significantly increased shoot biomass in the Pb0Cu200, Pb300Cu0, and all Pb600 treatments. AM fungi enhanced plant Cu acquisition, but decreased plant Cu concentrations with all Cu plus Pb treatments, except for shoot in the Cu200Pb600 treatment. Irrespective of Cu and Pb levels, +M plants had higher Pb uptakes than -M plants, but had lower root Pb and higher shoot Pb concentrations than those of -M plants. Another interpretation for the higher shoot Pb concentration in +M plants relied on Cu-Pb interactions. The study provided further evidences for the protective effects of AM fungi on upland rice against Cu and Pb contamination, and uncovered the phenomenon that Cu addition could promote Pb uptake and Pb partitioning to shoot. The possible mechanisms by which AM fungi can alleviate the toxicity induced by Cu and Pb are also discussed. PMID:25326862

Lin, Aijun; Zhang, Xuhong; Yang, Xiaojin

2014-12-01

107

The relative roles of N fixation, fertilizer, crop residues and soil in supplying N in multiple cropping systems in a humid, tropical upland cropping system  

Microsoft Academic Search

This work provides information relevant to the nitrogen (N) management strategy of multiple cropping in upland systems in the humid tropics of the transmigration areas of Sumatra, Indonesia. The experiment was conducted on a red yellow podzolic (orthoxic palehumult) soil at Kota Bumi in Lampung Province, Indonesia, where the annual rainfall of 2430 mm allows three consecutive crops per year

Widjang H. Sisworo; M. M. Mitrosuhardjo; Havid Rasjid; R. J. K. Myers

1990-01-01

108

Stable Isotope Probing of Peat and Forest Floor Amendments  

NASA Astrophysics Data System (ADS)

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.

Quideau, Sylvie; Béasse, Mark

2013-04-01

109

Molecular analysis of the major capsid genes ( g23 ) of T4-type bacteriophages in an upland black soil in Northeast China  

Microsoft Academic Search

Bacteriophages (phages) are the most abundant biological entities on the planet and are important as the greatest genomic\\u000a reservoirs in both marine and terrestrial environments. In this study, we analysed T4-type phage communities in an upland\\u000a black soil by monitoring g23 clones in DNA extracted from seasonal soil samples with no fertilizer, chemical fertilizers, chemical fertilizers plus manure,\\u000a and natural

Guanghua Wang; Zhenhua Yu; Junjie Liu; Jian Jin; Xiaobing Liu; Makoto Kimura

2011-01-01

110

[Dynamics of upland field P pool under a long-term application of fertilizer P in yellow soil area and their effects on P concentration in runoff].  

PubMed

Studies on the dynamics of upland field P pool under a long-term application of fertilizer P in yellow soil area and their effects on P concentration in runoff showed that the contents of A1-P, Fe-P and Ca-P in soil cultivated layer increased greatly, and Olsen-P and algae-available P also accumulated obviously. The correlation coefficients of algae-available P content in the high-P soils (Olsen-P > 25 mg.kg-1) with the quantities of A1-P, Fe-P and Ca-P were 0.859**, 0.903** and 0.650*, respectively, of which, Fe-P was the most important. By a 30-min rainfall simulation experiment with a constant rainfall rate of 63.2 mm.h-1, the concentrations of dissolved reactive P and bio-available P in runoff from low-P upland fields (Olsen-P 4.62-15.9 mg.kg-1) were 2.81-4.17 micrograms.L-1 and 0.723-0.876 mg.L-1, respectively, whereas their concentrations in runoff from high-P upland fields (Olsen-P 29.4-59.2 mg.kg-1) were 0.026-0.714 mg.L-1 and 0.996-1.281 mg.L-1, respectively. Therefore, runoff from high-P upland fields could accelerate water eutrophication. PMID:12827870

Liu, Fang; Huang, Changyong; He, Tengbin; Qian, Xiaogang; Liu, Yuansheng; Luo, Haibo

2003-02-01

111

Effects of soils and grazing on breeding birds of uncultivated upland grasslands of the Northern Great Plains  

USGS Publications Warehouse

The principal use of uncultivated upland grasslands in the northern Great Plains is for livestock production. However, on lands set aside for wildlife or for scientific or recreational use, grazing by livestock may be used as a management measure to enhance populations of game species or to create conditions that increase the diversity of plant or animal species. To determine the effects of grazing on the avifauna of various types of Great Plains grasslands, we conducted bird censuses and plant surveys during 1974-78 on 615 plots of lightly, moderately, or heavily grazed native rangeland.Numbers of horned lark (Eremophila alpestris), western meadowlark (Sturnella neglecta), lark bunting (Calamospiza melanocorys), and chestnut-collared longspur (Calcarius ornatus) accounted for 65-75% of the total bird population, regardless of grazing intensity. For the entire area sampled (600,000 km2), horned lark, western meadowlark, and chestnut-collared longspur were the dominant birds. Major differences in composition of the dominant species and species richness occurred among the major soils. Increased mean annual soil temperature seemingly had a greater negative influence on avian species richness than did decreased soil moisture or organic matter content. Differences in total bird density were not significant among soils and among grazing intensities within most soils. For the area as a whole, light or moderate grazing resulted in increased species richness. Of the 29 species studied, 2 responded significantly to grazing for the area as a whole and 6 others to grazing on the soil in which peak densities occurred. Response of several other species to grazing effects evidently varied among strata.A list of plants with mean cover values of more than 1% in any of the 18 combinations of soils and grazing intensities contained less than 25 species, attesting to the relative simplicity of the grassland vegetation in the northern Great Plains. Agropyron spp. and Bouteloua gracilis were the dominant plants that provided greater than average cover on the best habitat for the most bird species. Optimum habitat for each bird species is given in terms of grazing, soils, and dominant plant species. Increased soil temperature probably had a negative effect on plant species richness, especially among soils with a high organic matter content that supported perennial grasses and other mesophytes.

Kantrud, H.A.; Kologiski, R.L.

1982-01-01

112

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

SciTech Connect

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.

Houser, Jeffrey N [ORNL

2005-01-01

113

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

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.

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

2005-01-01

114

Simulating the effect of land use and climate change on upland soil carbon stock of Wales using ECOSSE  

NASA Astrophysics Data System (ADS)

Within Wales soils hold between 400-500 MtC, over half of this carbon is stored in organic and organo-mineral soil which cover less than 20% of the land area of Wales. It has been predicted that climate change will increasingly have an impact on the C stock of soils in Wales. Higher temperatures will increase the rate of decomposition of organic matter, leading to increased C losses. However increased net primary production (NPP), leading to increased inputs of organic matter, may offset this. Land use plays a major role in determining the level of soil C and the direction of change in status (soil as a source or sink). We present here an assessment of the effect of land use change and climate change on the upland soil carbon stock of Wales in 3 different catchments i.e. Migneint, Plynlimon and Pontbren using a process-based model of soil carbon and nitrogen dynamics, ECOSSE. The uncertainties introduced in the simulations by using only the data available at national scale are determined. The ECOSSE model (1,2) has been developed to simulate greenhouse gas emissions from both organic and mineral soils. ECOSSE was derived from RothC (3) and SUNDIAL (4,5) and predicts the impacts of changes in land use and climate on emissions and soil carbon stock. Simulated changes in soil C are dependent on the type of land use change, the soil type where the land use change is occurring, and the C content of soil under the initial and final land uses. At Migneint and Plynlimon, the major part of the losses occurs due to the conversion of semi-natural land to grassland. Reducing the land use change from semi-natural to grassland is the main measure needed to mitigate losses of soil C. At Pontbren, the model predicts a net gain in soil C with the predicted land use change, so there is no need to mitigate. Simulations of future changes in soil C to 2050 showed very small changes in soil C due to climate compared to changes due to land use change. At the selected catchments, changes in soil C due to the impacts of land use change were predicted to be up to 1000 times greater than the changes predicted due to climate change. This is encouraging, as it illustrates the great potential for C losses due to climate change to be mitigated by changing land use. 1. Smith P, et al 2007. SEERAD Report. ISBN 978 0 7559 1498 2. 166pp. 2. Smith JU, et al 2009. RERAD Report. In press. 3. Coleman K & Jenkinson DS 1996. In: Evaluation of Soil Organic Matter Models Using Existing, Long-Term Datasets, NATO ASI Series I, Vol.38 (eds Powlson DS, Smith P, Smith JU), pp. 237-246. Springer-Verlag, Heidelberg, Germany. 4. Bradbury NJ, et al 1993. Journal of Agricultural Science, Cambridge 121, 363-379. 5. Smith JU, et al 1996. Agronomy Journal 88, 38-42.

Rani Nayak, Dali; Gottschalk, Pia; Evans, Chris; Smith, Pete; Smith, Jo

2010-05-01

115

Degrading uplands in the rainforest region of Madagascar: Fallow biomass, nutrient stocks, and soil nutrient availability  

Microsoft Academic Search

Soil fertility restoration depends on natural fallows in the slash-and-burn system of eastern Madagascar. In the Beforona-Vohidrazana\\u000a study zone, none of the fallow species are able to withstand the slashing, burning and cropping frequencies of 3–5 years.\\u000a Eventually soils are abandoned for agriculture. Along the degradation sequence, this study quantifies fallow biomass, nutrient\\u000a stocks and soil nutrient availability of four dominant

Erika Styger; Erick C. M. Fernandes; Harivelo M. Rakotondramasy; Eric Rajaobelinirina

2009-01-01

116

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

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.

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

2000-01-01

117

Bole respiration in a closed-canopy upland oak forest before and after soil moisture manipulations  

SciTech Connect

A throughfall displacement system was established in an upland oak forest stand on Walker Branch Watershed in the fall of 1993. Three 80[times]80 m plots were established adjacent to each other. The system is designed to displace 33% of the throughfall from one plot to another with one ambient plot. Pretreatment and first year post-treatment bole respiration rates were determined at intervals throughout the 1993 and 1994 growing seasons on mature Acer rubrum L., Quercus alba L, and Quercus prinus L. Maintenance and growth respiration data will be presented. Preliminary analysis of the pretreatment data, expressed as CO[sub 2] evolved per unit of cambial surface area, showed positive correlations between tree diameter, sapwood volume, and respiration rates during the [open quotes]dormant[close quotes] season. However, these correlations did not appear during diameter growth, indicating that cambial activity may be the major source of CO[sub 2] efflux from the bole surface during the growing season.

Edwards, N.T.; Hanson, P.J. (Oak Ridge National Laboratory, TN (United States))

1994-06-01

118

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

USGS Publications Warehouse

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.

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

1990-01-01

119

Draft Genome Sequences of Two Antimicrobial-Producing Burkholderia sp. Strains, MSh1 and MSh2, Isolated from Malaysian Tropical Peat Swamp Forest Soil  

PubMed Central

We report the draft genome sequences of two antimicrobial-producing isolates, Burkholderia sp. strains MSh1 and MSh2, which were isolated from tropical peat swamp forest soil. Putative genes related to different antimicrobial production have been annotated in both genome sequences. PMID:25301661

Aw, Yoong Kit; Gan, Han Ming; Yule, Catherine M.; Lee, Sui Mae

2014-01-01

120

Soils of cryogenic subarid steppe landscapes in the Terekhol intermontane Depression of the Sangilen Upland  

NASA Astrophysics Data System (ADS)

The soil cover of the Terekhol intermontane Depression in the Tyva Region is poorly studied. The data obtained in the 1950s do not reflect the real genetic diversity of soils and their specific character. According to these data, the soil cover was dominated by meadow-chernozemic soils under virgin steppe-like meadows. The investigations of 2007-2009 show that the disperse-carbonate chernozems, which are often solonetzic and weakly saline; the specific polygenetic dark soda solonchaks-solonetzes; and the postagrogenic chernozems, solonetzes, and agrozems are the main components of the soil cover of the depression at the present time. The described chernozems correspond mainly to the central image of southern Siberia chernozems. The investigated solonetzes are characterized by a number of evolution-genetic features that distinguish them from previously described solonetzes of Tyva and from all the solonetzic soils in the current interpretation. The chernozems and solonetzes have cryogenic features due to the cold extremely continental climate and relatively shallow continuous permafrost.

Bronnikova, M. A.; Turova, I. V.; Kuznetsova, E. P.; Kozlov, D. N.; Khokhlova, O. S.

2011-06-01

121

Glasshouse evaluation of the growth of Alnus rubra and Alnus glutinosa on peat and acid brown earth soils when inoculated with four sources of Frankia  

Microsoft Academic Search

The effects of soil type (an acid peat and 2 acid brown earths) andFrankia source (3 spore-positive crushed nodule inocula and spore-negative crushed nodules containing the singleFrankia ArI5) on nodulation, N content and growth ofAlnus glutinosa andA. rubra were determined in a glasshouse pot experiment of two years duration. Plants on all soils required additional P for growth. Growth of

L. J. Sheppard; J. E. Hooker; C. T. Wheeler; R. I. Smith

1988-01-01

122

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

NASA Astrophysics Data System (ADS)

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.

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

2013-11-01

123

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

NASA Astrophysics Data System (ADS)

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.

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

2010-05-01

124

Soil-atmosphere fluxes of carbon monoxide during early stages of postfire succession in upland Canadian boreal forests  

NASA Astrophysics Data System (ADS)

Soil-atmosphere fluxes of carbon monoxide (CO) were investigated during BOREAS 1994 (June to September 1994) in forest sites near the northern study area (NSA) of the Boreal Ecosystem-Atmosphere Study (BOREAS). Fluxes and related ancillary data were measured for both upland black spruce (located on poorly drained clay-textured soils) and jack pine sites (well-drained sandy soils) that were in early stages of succession following stand replacement fires that occurred within 7 years of BOREAS 1994. Nearby control stands that had not burned in the past 80 years were studied for comparison. Net fluxes measured by using transparent closed chambers were generally positive at the warmer, sunlit burn sites but negative (sink activity) in the shaded, cooler control sites. Carbon monoxide uptake in controls, which was first order with respect to CO concentration, was little affected by covering the sampling chambers to exclude light. Median deposition velocities calculated from the uptake fluxes were 0.015 cm s-1 at the black spruce control site and 0.0085 cm s-1 at the jack pine control site, at the lower end of the range of values observed by others in tropical and temperate ecosystems. Daytime CO fluxes at the burn sites were generally positive (1011-1012 molecules cm-2 s-1) and were lowered when solar irradiance was excluded from the chambers by covering or when cloudiness or smoke reduced the light intensity. Net fluxes at the burn sites were controlled by competition between abiotic production, mainly at the surface, and by oxidation deeper in the soil. Abiotic production, which was attributable to photoproduction and thermal decomposition of the surface organic layer and charcoal, strongly correlated with incident solar irradiance, and thus the greatest fluxes were observed during midday. Results of these studies indicate that the locally dependent changes in boreal fire return intervals that are linked to global climate change represent an important biospheric/physical feedback that is likely to alter the biosphere-atmosphere exchange of CO.

Zepp, Richard G.; Miller, William L.; Tarr, Matthew A.; Burke, Roger A.; Stocks, Brian J.

1997-12-01

125

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

SciTech Connect

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.

Galbraith, H.; LeJeune, K.; Lipton, J. [Hagler Bailly Consulting, Inc., Boulder, CO (United States)

1995-11-01

126

The peats of Costa Rica  

SciTech Connect

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.

Obando A, L.; Malavassi R, L.; Ramirez E, O. (RECOPE, San Jose (Costa Rica)); Cohen, A. (South Carolina Univ., Columbia, SC (USA). Dept. of Geological Sciences); Raymond, R. Jr.; Thayer, G.R. (Los Alamos National Lab., NM (USA))

1991-04-01

127

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

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

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

2009-01-01

128

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

NASA Astrophysics Data System (ADS)

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.

Bernardi, Tony

2014-05-01

129

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

NASA Astrophysics Data System (ADS)

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.

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

2013-04-01

130

Origin of lead associated with different reactive phases in Scottish upland soils: an assessment made using sequential extraction and isotope analysis.  

PubMed

Soil samples (0-25 cm) have been taken annually since 1991 from three protected plots set up at an upland location at Glensaugh in Aberdeenshire, Scotland. The soils were analysed using the original BCR sequential extraction procedure and the lead isotopic composition was determined in each of the fractions, as well as the unfractionated soil using thermal ionisation mass spectrometry (TIMS). The lead concentrations in all the soils, including those well away from the road, were much higher than typical background values indicating that the whole area has been subject to deposition of anthropogenic lead. The distribution of lead between the different fractions was similar for the two non-roadside soils with most lead present in the oxidizable fraction. Although most lead in the roadside soil was also present in the oxidizable fraction, a substantial proportion (about 10%) was in the easily soluble fraction suggesting that roadside lead could be more mobile than lead in the other soils. Good reproducibility was obtained for the isotope analyses in all the fractions. The ratios calculated for the bulk soil from the ratios in the individual fractions agreed very closely with those measured directly in the unfractionated soil thereby demonstrating both reproducibilty and accuracy. The lowest (206)Pb/(207)Pb ratios were found in the roadside soil consistent with the recent deposition of petrol lead. The (206)Pb/(207)Pb ratios in all fractions of the other soils fell into a narrow band and it was necessary to use (204)Pb ratios to differentiate between lead in the extractable fractions and lead in the residual component. It is probable that lead in the non-roadside soils was deposited a considerable time ago and is characterised by a relatively high (206)Pb/(207)Pb ratio. Use of the (204)Pb ratios showed that the residual components in each of the three soils were isotopically distinct. PMID:15346181

Bacon, Jeffrey R; Hewitt, Irene J; Cooper, Patricia

2004-09-01

131

Mycobiota of peat-gleyic soils during the process of recultivation  

NASA Astrophysics Data System (ADS)

The experiments on the recultivation of oil-polluted soils and their self-rehabilitation were laid in 1995 at sites contaminated with oil in the area of Usinsk region, Komi Republic, Russia. There were taken different plots for the experiment with various amounts of contaminant. The investigations continued some years after the contamination. At this point, the concentration of residual oil in these areas significantly decreased. Microbiological activity increased 2-3 times in the most contaminated soil. We should note that the micromycets were marked only in the layer 0-5sm in contrast to background soil. There were 10 species of micromycets and most of them characterized as dark colored species, the dominants were Aspergillus fumigatus. Penicillium funiculosum, P. paxilli, P. lanosum, P. tardum, usual for contaminated anthropogenic soils. The same highly oil-polluted soil, where recultivation was held, is characterized with the wider specter of different physiological groups of microorganisms. Micobiota is quite reach, it represents 20 species from 8 types. In the composition of micromycets 40% are the representatives of Penicillium, sterile mycelium presents as dark colored forms so as light colored ones. But the micobiota is still reach in micromycets typical for disturbed anthropogenic soils. The most microbiologically active plot was a territory with low-contaminated self-recovered soil. The micobiota is represented of great amount of microorganisms and consists of 21 species, mostly formed with dark colored forms of sterile mycelium. During the process of recultivation the structure of micromyctes changed: regrouping of species and increase of biodiversity. We assume that a process of self-purification started. However we should notice that activation of biological processes doesn't occur deeper than 0-5sm. At the same time the roots of high plants are seen till the depth 7-10sm, they also participate in the cleaning of oil polluted soil. There was used a Zhakkar coefficient of similarity to show the difference of mycobiota structure of rehabilitated ecosystems. The greatest similarity was observed between the communities of soil micromycetes from recultivated area and the area with low pollution (42.8%), the smallest - mycobiota of a non-polluted and heavily contaminated soil (5.4%). Mikobiota of virgin soil is characterized with the richest biodiversity of micromycetes species; rates of similarity coefficient between the mycobiota of virgin soils and oil-polluted here have the lowest value. In summary, we want to mark that micromycet complexes are changing in soils under the influence of oil pollution: first, a reduction in the diversity of fungal complexes in the soil, compared with the background, and secondly, there is an increase of dominant and often encountered species and reducing the number of rare species. There is also the appearance of fungi, which are typical for the more southern regions. Influenced by oil pollution the investigated soils become a sphere of accumulation of potentially hazardous to human species of micromycetes: Aspergillus fumigatus, Paecilomyces variotii, etc.

Ibatullina, I.; Khabibullina, F.

2009-04-01

132

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

NASA Astrophysics Data System (ADS)

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

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

2013-04-01

133

Sequential extraction combined with isotope analysis as a tool for the investigation of lead mobilisation in soils: Application to organic-rich soils in an upland catchment in Scotland  

Microsoft Academic Search

Sequential extraction (modified BCR procedure) combined with isotope analysis has been investigated as a tool for assessing mobilisation of lead into streams at an upland catchment in NE Scotland. The maximum lead concentrations (up to 110mgkg?1 in air-dried soil) occurred not at the surface but at about 10cm depth. The lowest 206Pb\\/207Pb ratios in any profile occurred, with one exception,

Jeffrey R. Bacon; John G. Farmer; Sarah M. Dunn; Margaret C. Graham; Susan I. Vinogradoff

2006-01-01

134

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

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

135

Metagenomic insights into anaerobic metabolism along an Arctic peat soil profile.  

PubMed

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

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

2013-01-01

136

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

NASA Astrophysics Data System (ADS)

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.

Karki, S.; Elsgaard, L.; Lærke, P. E.

2014-09-01

137

What are the mechanisms controlling carbon flux from peat soils across slopes?  

NASA Astrophysics Data System (ADS)

Peatlands are a globally important terrestrial carbon stock but carbon budget models need further improvement. The use of empirical observations to increase the accuracy of process based models has helped to constrain the error involved in accounting for peatland carbon balances, yet our understanding of peatland function needs to improve still further. Hydrology and topography are important controls on the carbon balance of peatlands. The hydrology of hillslopes has been studied, with runoff mechanisms and flow pathways dependent upon the topographic position. Topslope plateau areas have been observed to promote a large degree of surface runoff, acting as a shedding area delivering water downslope. Midslopes may experience fewer saturation runoff events due to the greater hydraulic gradient, with lower water tables likely to cause subsurface throughflow that is delivered downslope at the accumulation area at the bottom of the slope. This can help to maintain higher water tables at the foot of the slope and attenuate saturation runoff events (Holden and Burt 2003). The different hydrological mechanisms studied across the hillslope have not until recently been studied in the context of carbon cycling as well. The author has presented results elsewhere on the role that hillslope position has on carbon flux, finding that with water table drawdown observed on the midslopes, there is a concurrent increase in the rates of ecosystem respiration dependent upon the changing depth of the water table. There is also a decrease in the concentration of dissolved organic carbon concentration downslope. This poster presents preliminary results looking to constrain the explanations for the changing levels of respiration and dissolved organic carbon content across the slope. One metre deep soil cores were taken from an intact and an eroded hillslope in the Peak District, UK, across four hillslope positions: topslope, upper midslope, lower midslope and bottomslope. The cores were analysed for bulk density, energy content using bomb calorimetry and CHNO to assess if the composition and structure of the soil substrate could explain observed changes across the slope in dissolved organic carbon content.

Boothroyd, I.; Worrall, F.; Allott, T.

2012-04-01

138

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)

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.

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

2012-12-01

139

Long-term stability of permafrost in subarctic peat plateaus, west-central Canada  

Microsoft Academic Search

Long-term vegetation succession and permafrost dynamics in subarctic peat plateaus of west-central Canada have been studied through detailed plant macrofossil analysis and extensive AMS radiocarbon dating of two peat profiles. Peatland inception at these sites occurred around 5800–5100 yr BP (6600–5900 cal. BP) as a result of paludification of upland forests. At the northern peat plateau site, located in the

A. Britta K. Sannel; Peter Kuhry

2008-01-01

140

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...

141

Biodiversity Toolkit Why we DON'T DIG PEAT  

E-print Network

Biodiversity Toolkit Peat free Why we DON'T DIG PEAT The collegiate University is working to help the environment and wildlife by phasing out its use of products containing peat, such as compost and soil improver. This will help the University meet its Biodiversity Policy, which was agreed by University Council in 2008: www.admin.ox.ac.uk/estates/environment/biodiversity

Melham, Tom

142

Small scale soil carbon and moisture gradients in a drained peat bog grassland and their influence on CO2, CH4 and N2O fluxes  

NASA Astrophysics Data System (ADS)

Due to the UNFCCC report requirements of each country on the emissions of greenhouse gases from key sources the joint research project "Organic Soils" was established in Germany. The project's objective is to improve the data set on greenhousegas emissions from organic soils in Germany. Within 12 German Project Catchments emissions from different types of organic soils, e.g. under different land uses and hydrological conditions, are measured. At the location "Großes Moor" near Gifhorn (Lower Saxony) the effects of small-scale soil organic carbon and groundwater level gradients on the GHG fluxes (CO2, CH4 and N2O) are quantified. The study area is located within a former peat bog altered by drainage and peat cutting, which is currently grassland under extensive agricultural use. The focus of the study is on the acquisition of CO2, CH4 and N2O fluxes on six sites via manual closed chambers. In order to calculate the annual CO2 exchange rate, values are interpolated on a 0.5 hour scale between measurement campaigns. In combination with continually logged meteorological parameters, such as the photosynthetic active radiation as well as air and soil temperatures, we calculate the daily CO2 ecosystem exchange of the different sites. During the 2011 campaign, CO2 was determined as the most important greenhouse gas. The groundwater table was the dominant variable influencing gas emissions. Another important factor was the vegetation composition. In detail, highest CO2 emissions occurred with a water table of 40-50 cm below ground level, temperatures above 10°C and low plant biomass amounts. Due to the more complex formation of N2O by a number of processes, each being promoted by different soil conditions, the measurement of N2O fluxes in the field was complemented by a laboratory experiment. In this, the use of stable isotope tracer techniques enabled us to quantify the contribution of single biochemical pathways to the overall formation of N2O under controlled conditions. This together with the prediction of the systems CO2 exchange, gives valuable information on how degraded peatlands can be restored best or at least be cultivated in a way to achieve climate neutral conditions. Thus, our study improves the prediction, how peatland soils will react to changes of soil and climate conditions with respect to their greenhouse gas emissions.

Leiber-Sauheitl, K.; Fuß, R.; Freibauer, A.

2012-04-01

143

Morphology, morphogenesis and molecular phylogeny of a novel soil ciliate, Pseudouroleptus plestiensis n. sp. (Ciliophora, Oxytrichidae), from the uplands of Colfiorito, Italy.  

PubMed

The terrestrial oxytrichid ciliate Pseudouroleptus plestiensis n. sp., isolated from soil samples collected from the uplands of Colfiorito (Umbria region, Italy), was investigated using live observation and protargol impregnation. The morphology, morphogenesis and molecular phylogeny inferred from small-subunit (SSU) rRNA gene sequences were studied. The novel species is mainly characterized by the following: a cell size of about 145×35 µm in vivo; two ellipsoidal macronuclear nodules and two to four micronuclei; adoral zone about 26% of body length with a mean of 30 membranelles; about 40 cirri in the right marginal row and 38 in the left marginal row; left fronto-ventral row consisting of about 27-40 cirri, right fronto-ventral row of about three to seven cirri forming a short row to the right of the rear portion of the left fronto-ventral row; one parabuccal cirrus (?=?III/2), one buccal and one post-peristomial cirrus; and four dorsal kineties with caudal cirri at the end of kineties 1 and 2. The morphogenesis of the novel species is similar to that of Pseudouroleptus caudatus. Phylogenetic analyses based on SSU rRNA gene sequences consistently placed the novel species within the family Oxytrichidae Ehrenberg, 1838, clustering with P. caudatus and the genus Strongylidium. The results from the present study contribute to the expanding knowledge of the diversity of ciliates in Italian soil. PMID:24824635

Bharti, Daizy; Kumar, Santosh; La Terza, Antonietta

2014-08-01

144

Sequential extraction combined with isotope analysis as a tool for the investigation of lead mobilisation in soils: application to organic-rich soils in an upland catchment in Scotland.  

PubMed

Sequential extraction (modified BCR procedure) combined with isotope analysis has been investigated as a tool for assessing mobilisation of lead into streams at an upland catchment in NE Scotland. The maximum lead concentrations (up to 110 mg kg(-1) in air-dried soil) occurred not at the surface but at about 10 cm depth. The lowest (206)Pb/(207)Pb ratios in any profile occurred, with one exception, at 2.5-5 cm depth. In the one exception, closest to the only road in the area, significantly lower (206)Pb/(207)Pb ratios in the surface soil together with much increased chloride concentrations (in comparison to other surface waters) indicated the possible mobilisation of roadside lead and transfer to the stream. The (206)Pb/(207)Pb ratios in extractable fractions tended at depth towards the ratio measured in the residual phase but the ratios in the oxidizable fraction increased to a value higher than that of the residual phase. PMID:16246474

Bacon, Jeffrey R; Farmer, John G; Dunn, Sarah M; Graham, Margaret C; Vinogradoff, Susan I

2006-06-01

145

Properties and structure of raised bog peat humic acids  

NASA Astrophysics Data System (ADS)

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.

Klavins, Maris; Purmalis, Oskars

2013-10-01

146

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

NASA Astrophysics Data System (ADS)

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.

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

2012-04-01

147

Effects of cropping history and peat amendments on the quality of a silt soil cropped with strawberries  

Microsoft Academic Search

Long-term field experiments are invaluable sites for studying changes in soil quality due to management practices. We utilized a field experiment on silt soil with 18 years (1982–1999) of conventional and organic farming systems for studying long-term impacts of farming system on soil properties. During 2000–2002, strawberries were grown on the whole area. Some conventional and organic plots were amended

Mauritz Vestberg; Sanna Kukkonen; Kaisa Saari; Tuomo Tuovinen; Ansa Palojärvi; Timo Pitkänen; Timo Hurme; Milja Vepsäläinen; Maarit Niemi

2009-01-01

148

Heavy metals deposited from the atmosphere on upland Scottish soils: Chemical and lead isotope studies of the association of metals with soil components  

NASA Astrophysics Data System (ADS)

Three soil profiles taken from the Hartwood Research Station in Central Scotland have been analyzed using chemical digestion and extraction techniques to investigate the chemical association of heavy metals deposited from the atmosphere. Total digestion, EDTA extraction and the BCR (Bureau Communitaire de Reference) sequential extraction procedure were used. In addition, lead isotope ratios in the whole soils and in the fractions from the sequential extraction procedure were measured using thermal ionisation mass spectrometry. All the digestion and extraction procedures gave clear indication of enhanced concentrations of heavy metals in surface soils, in particular for lead and zinc. Whereas total digestion gave a good indication of the heavy metal status of the soils, the extraction procedures were necessary to provide information on chemical association of the metals with soil components, information needed to understand the soil processes involved in mobilization of metals. Lead isotope analysis of the whole soils revealed a consistent picture of lower 206Pb/ 207Pb ratios in surface soils (1.140-1.147) than in soils at 20-30 cm depth (1.182-1.190). The steady progression from the lower to higher ratios down the profile was clear indication that anthropogenic lead had penetrated to some degree into the deeper soils. The combination of sequential extraction and lead isotope analysis proved to be a powerful approach to studying this effect in more detail and showed that the fractions extractable from 20 to 30 cm soils contained lead with much lower 206Pb/ 207Pb ratios (1.174-1.178) than the residual fraction (1.196-1.200). As the extractable fractions contained ?85% of the lead in the soil, a substantial portion of lead at 20-30 cm depth was of anthropogenic origin. The 206Pb/ 207Pb ratios of 1.174-1.178 found in the extractable fractions suggested that the mobile component of the anthropogenic lead was that deposited before the introduction of leaded petrol.

Bacon, Jeffrey R.; Hewitt, Irene J.

2005-01-01

149

Inorganic contents of peats  

SciTech Connect

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.

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

1988-02-01

150

Coupling of groundwater, river flow and rainfall in an upland floodplain  

NASA Astrophysics Data System (ADS)

Upland floodplains provide an important function in regulating river flows and controlling the coupling of hillslope runoff with rivers. To investigate the responses of floodplain groundwater to river flows and rainfall events, a small floodplain in an upland area of the River Tweed catchment, Scotland, was characterised using geophysics, 3D geological mapping and hydrogeological testing; and monitoring undertaken from September 2011 to February 2013 of: groundwater levels in five pairs of piezometers; river stage and flow at the upstream and downstream limits of the study site; soil moisture on the adjacent hillslope; and meteorological parameters. Periodical groundwater chemistry and residence data were also collected. The floodplain aquifer is permeable throughout but partially stratified, comprising dominantly alluvial and glaciofluvial sandy gravels between 8 and 15m interspersed with thin, intermittent layers of low permeability silts, clays and peats. Overlying the gravel aquifer is a partial thin cover of low permeability alluvial silts, and it is underlain dominantly by low permeability glaciolacustrine silts and clays. High permeability solifluction deposits mantle much of the adjacent hillslope and provide a rapid connection to the floodplain aquifer. The unusually wet year of 2012 provides a good example of how a temperate upland floodplain responds to consistently high rainfall. Statistical analysis and graphical interpretation of groundwater level, rainfall, soil moisture and river stage demonstrates that: 1) dominant groundwater flow within the floodplain is in the same direction as the river, from up-valley to down-valley; 2) soil moisture in the hillslope is strongly correlated with local rainfall, but groundwater across much of the floodplain is more strongly influenced by river stage; except 3) groundwater near the edge of floodplain, which responds more slowly to local rainfall and river stage changes ; and 4) subsurface flow from the hillslope to the floodplain occurs during high rainfall events. A detailed investigation of three flood events, when the river rose above bank level and flooded adjacent fields and groundwater became artesian in parts of the floodplain, suggests that antecedent moisture conditions can partly explain the differences in groundwater response during different flood events, where high intensity or long duration rainfall can cause saturated soil conditions, reducing soil water storage capacity and hence promoting flood conditions. A conceptual model based on field data of groundwater flow after storm events during antecedent unsaturated and saturated soil conditions is presented.

Archer, Nicole; Dochartaigh, Brighid Ó.; MacDonald, Alan; Bonell, Mike; Black, Andrew; Coles, Neil

2014-05-01

151

Geomorphic, sedimentary, and potential palaeoenvironmental significance of peat blocks in alluvial river systems  

NASA Astrophysics Data System (ADS)

Fluvial erosion of peat deposits occurs in many environmental settings; however, the erosion and transport of large peat blocks by river channels has received relatively little attention. This paper describes the sedimentary significance and potential palaeoenvironmental interpretation of peat blocks in alluvial river systems. Evidence is presented from a number of field studies of upland river systems in northern England that illustrate a range of peat block forms and sedimentary features that are briefly compared with examples of peat blocks preserved in gravel stratigraphy. We show that peat blocks are an important geomorphological and sedimentological component of upland rivers draining eroding peatland catchments. They are of widespread occurrence and contribute significantly to river channel roughness and channel sedimentation. A variety of common sedimentary features can be observed including, shadow, crescent, perched, armoured, drape, embedded (part buried), cluster, and step forms. Peat blocks tend to be deposited on channel margins and bar tops and can be used as “maximum” stage indicator for major floods. The role of peat blocks in controlling sedimentation varies with channel width. In narrow channels where the size of the peat block approximates the channel width, blocks become jammed in the channel and exert a primary control on channel sedimentation. In wider channels, blocks tend to occur in isolation or in small clusters and are of only secondary importance in controlling sedimentation. Residence times of peat blocks varies from short periods of temporary deposition (days to months) to much longer timescales (months to years) with some blocks becoming permanently incorporated into the sedimentary record. The sedimentary characteristics of contemporary buried peat blocks have much in common with blocks preserved in alluvial gravel stratigraphy. This offers the potential for using these features for palaeoenvironmental reconstruction. Peat blocks in many ways are analogous to other low density geological materials (ice blocks, woody debris, and some volcanic sediments), and recognising the special sedimentological characteristics of this suite of materials is important as they are not always adequately characterised using conventional hydraulic relationships.

Warburton, Jeff; Evans, Martin

2011-07-01

152

Significance of large peat blocks for river channel habitat and stream organic budgets  

Microsoft Academic Search

SUMMARY This paper examines the significance of large peat blocks in Trout Beck, an upland gravel-bed river in northern England. An inventory was made of all in-channel peat blocks over a 1.5 km reach of the river in order to characterise the distribution of the blocks, and benthic organic matter and periphyton were sampled from the gravel around an isolated

S. Crowe; J. Warburton

2007-01-01

153

Function of peatland located on secondary transformed peat-moorsh soils on the purification processes of groundwater and the impact of pH on the rates of the elution of organic matter  

NASA Astrophysics Data System (ADS)

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 four investigated points along to Wyskoc ditch. Two times a month during entire vegetation season the following material was taken from this four chosen sites: 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 elution 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. All experiments were repeated at different pH 6.0, 6.5, 7.0, 8.0, 8.5 of 0.5 M ammonium acetate buffer solution. The investigations have shown the impact of the properties of secondary transformed peat-moorsh soils on the rates of the dissolution of organic matter. The rates of organic matter elution for all samples of peats were significant different at four used wavelengths ?=272 nm, ?=320 nm, ?=465 nm, and ?=665 nm. It was observed that the rates increased between ?=272 nm and ?=320 nm and decreased from ?=465 nm to ?=665 nm. Although, the lowest values of the pseudo first-order rate constants measured at ?=665 nm for all samples of peats from four places ranged from 1.9524 10-4 s-1 to 2.7361 10-4 s-1. Therefore, the highest values of t0.5 ranged from 42.2 to 59.2 min for all samples from Zb?chy, Shelterbelt, Mostek and Hirudo. This work was supported by a grant No. N N305 3204 36 founded by Polish Ministry of Education.

Wojciech Szajdak, Lech; Szczepa?ski, Marek

2010-05-01

154

Evaluating the spatial variation of total mercury in young-of-year yellow perch (Perca flavescens), surface water and upland soil for watershed-lake systems within the southern Boreal Shield  

USGS Publications Warehouse

The primary objective of this research is to investigate relationships between mercury in upland soil, lake water and fish tissue and explore the cause for the observed spatial variation of THg in age one yellow perch (Perca flavescens) for ten lakes within the Superior National Forest. Spatial relationships between yellow perch THg tissue concentration and a total of 45 watershed and water chemistry parameters were evaluated for two separate years: 2005 and 2006. Results show agreement with other studies where watershed area, lake water pH, nutrient levels (specifically dissolved NO3--N) and dissolved iron are important factors controlling and/or predicting fish THg level. Exceeding all was the strong dependence of yellow perch THg level on soil A-horizon THg and, in particular, soil O-horizon THg concentrations (Spearman ?? = 0.81). Soil B-horizon THg concentration was significantly correlated (Pearson r = 0.75) with lake water THg concentration. Lakes surrounded by a greater percentage of shrub wetlands (peatlands) had higher fish tissue THg levels, thus it is highly possible that these wetlands are main locations for mercury methylation. Stepwise regression was used to develop empirical models for the purpose of predicting the spatial variation in yellow perch THg over the studied region. The 2005 regression model demonstrates it is possible to obtain good prediction (up to 60% variance description) of resident yellow perch THg level using upland soil O-horizon THg as the only independent variable. The 2006 model shows even greater prediction (r2 = 0.73, with an overall 10??ng/g [tissue, wet weight] margin of error), using lake water dissolved iron and watershed area as the only model independent variables. The developed regression models in this study can help with interpreting THg concentrations in low trophic level fish species for untested lakes of the greater Superior National Forest and surrounding Boreal ecosystem. ?? 2009 Elsevier B.V.

Gabriel, M. C.; Kolka, R.; Wickman, T.; Nater, E.; Woodruff, L.

2009-01-01

155

Evaluating the spatial variation of total mercury in young-of-year yellow perch (Perca flavescens), surface water and upland soil for watershed-lake systems within the southern Boreal Shield.  

PubMed

The primary objective of this research is to investigate relationships between mercury in upland soil, lake water and fish tissue and explore the cause for the observed spatial variation of THg in age one yellow perch (Perca flavescens) for ten lakes within the Superior National Forest. Spatial relationships between yellow perch THg tissue concentration and a total of 45 watershed and water chemistry parameters were evaluated for two separate years: 2005 and 2006. Results show agreement with other studies where watershed area, lake water pH, nutrient levels (specifically dissolved NO(3)(-)-N) and dissolved iron are important factors controlling and/or predicting fish THg level. Exceeding all was the strong dependence of yellow perch THg level on soil A-horizon THg and, in particular, soil O-horizon THg concentrations (Spearman rho=0.81). Soil B-horizon THg concentration was significantly correlated (Pearson r=0.75) with lake water THg concentration. Lakes surrounded by a greater percentage of shrub wetlands (peatlands) had higher fish tissue THg levels, thus it is highly possible that these wetlands are main locations for mercury methylation. Stepwise regression was used to develop empirical models for the purpose of predicting the spatial variation in yellow perch THg over the studied region. The 2005 regression model demonstrates it is possible to obtain good prediction (up to 60% variance description) of resident yellow perch THg level using upland soil O-horizon THg as the only independent variable. The 2006 model shows even greater prediction (r(2)=0.73, with an overall 10 ng/g [tissue, wet weight] margin of error), using lake water dissolved iron and watershed area as the only model independent variables. The developed regression models in this study can help with interpreting THg concentrations in low trophic level fish species for untested lakes of the greater Superior National Forest and surrounding Boreal ecosystem. PMID:19349066

Gabriel, Mark C; Kolka, Randy; Wickman, Trent; Nater, Ed; Woodruff, Laurel

2009-06-15

156

The rhizosphere and PAH amendment mediate impacts on functional and structural bacterial diversity in sandy peat soil  

Microsoft Academic Search

To reveal the degradation capacity of bacteria in PAH polluted soil and rhizosphere we combined bacterial extradiol ring-cleavage dioxygenase and 16S rRNA analysis in Betula pubescens rhizoremediation. Characterisation of the functional bacterial community by RFLP revealed novel environmental dioxygenases, and their putative hosts were studied by 16S rRNA amplification. Plant rhizosphere and PAH amendment effects were detected by the RFLP\\/T-RFLP

Kim Yrjälä; Anna-Kaisa Keskinen; Marja-Leena Åkerman; Carola Fortelius; Timo P. Sipilä

2010-01-01

157

Review of pre-treated peat applied in treating domestic wastewaters and oily waters  

Microsoft Academic Search

Peat is commonly used as a combustible fuel for energy and as an addictive to soil in horticulture. For hundreds of years, peat was widely used as a green energy source for heating in the northern parts of Europe and North America. Nowadays, people tend to lay decomposed peat on lawns or gardens as a top layer because of its

Xiao Jiang; Cynthia A. Coles; Emmanuel S. Asapo

2008-01-01

158

A study of the compressibility behavior of peat stabilized by DMM: Lab model and FE analysis  

Microsoft Academic Search

Peats are considered as extremely soft, unconsolidated deposits. These soils are geotechnically problematic, due to their high compressibility and low shear strength. Cement is widely used for the stabilization of peat by deep mixing method (DMM). This paper presents the results of the model study of compressibility properties of fibrous, hemic and sapric peats, stabilized with columns formed by DMM.

B B K Huat; S Kazemian; A Prasad; M Barghchi

2011-01-01

159

Erosion-preventive crop rotations for landscape ecological stability in upland regions of Lithuania  

Microsoft Academic Search

A combination of perennial grass species and selected crop rotation can help prevent soil erosion in upland regions. Research data were obtained on sandy loam Dystric Albeluvisols at the Kaltinenai Research Station of the Lithuanian Institute of Agriculture on the undulating hilly topography of the Zemaiciai Uplands of Western Lithuania to identity crop and crop rotations that would minimise soil

Benediktas Jankauskas; Genovaite Jankauskiene

2003-01-01

160

Effect of steel-making slag as a soil amendment on arsenic uptake by radish ( Raphanus sativa L.) in an upland soil  

Microsoft Academic Search

The steel-making slag (SMS), a by-product of steel manufacturing process with an alkaline pH (11–12) and high amount of iron\\u000a (Fe) and calcium (Ca) oxides, was used to reduce arsenic (As) phytoextractability. The by-product was selected as an alternative\\u000a to commercial Fe oxides, which can decrease plant uptake, but they are expensive if used as amendments of contaminated arable\\u000a soils.

Jessie Gutierrez; Chang Oh Hong; Byung-Hyun Lee; Pil Joo Kim

2010-01-01

161

Examining the effect of pore size distribution and shape on flow through unsaturated peat using computed tomography  

Microsoft Academic Search

The hydraulic conductivity of unsaturated peat soil is controlled by the air-filled porosity, pore size and geometric distribution as well as other physical properties of peat materials. This study investigates how the size and shape of pores affects the flow of water through peat soils. In this study we used X-ray Computed Tomography (CT), at 45 mum resolution under 5

F. Rezanezhad; W. L. Quinton; J. S. Price; D. Elrick; T. R. Elliot; R. J. Heck

2009-01-01

162

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

SciTech Connect

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

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

1982-01-01

163

The link between peat hydrology and decomposition: Beyond von Post  

NASA Astrophysics Data System (ADS)

SummaryHydrology is central to the formation, growth and utilisation of peat soils. However, peat presents a difficult medium in which to measure hydrologic properties, due to its soft structure and high water content. The von Post scale is a widely used measure of the extent of decomposition of peat, which can be applied in the field or the laboratory without specialised equipment. von Post decomposition has been shown to correlate with hydraulic conductivity. However, it is a categorical and subjective measure of decomposition. Technological advances now enable peat chemistry to be described quantitatively and objectively. 13C nuclear magnetic resonance (NMR) is now routinely used to describe peat chemistry, and the capability of this technique has been extended by the development of the molecular mixing model (MMM). The MMM predicts the molecular composition of organic material from the spectral information provided by 13C NMR. We found significant relationships between the hydrologic properties hydraulic conductivity and water yield and peat chemistry as described by 13C NMR and the MMM. These relationships have potential application in all fields where the hydrologic properties of peat soils are of interest (i.e. peat mining, peatland restoration, catchment management) and also in modelling of peatland development and responses to climate change.

Grover, S. P. P.; Baldock, J. A.

2013-02-01

164

Sulfur mobility in peat  

Microsoft Academic Search

Lead-210 chronologies, vertical S concentration gradients and ?34S values are presented for 5 Sphagnum-dominated peat bogs located in Central Europe (Rybarenska slat and Ocean Bog; Czech Republic) and the British Isles (Thorne Moors, England; Connemara, Ireland; and Mull, Scotland). Sulfur concentrations were measured in three 40-cm deep peat cores per site, sectioned into 2-cm segments. The coefficient of variation in

Martin Novák; Marie Adamová; R. Kelman Wieder; Simon H. Bottrell

2005-01-01

165

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

PubMed

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

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

2014-10-01

166

Short period of oxygenation releases latch on peat decomposition.  

PubMed

Extreme summer droughts are expected to occur more often in the future in NW Europe due to climate change. These droughts might accelerate the rate of peat oxidation in drained peat areas, with impacts on soil subsidence, GHG emission and water quality. This study aimed at providing more insight in the oxidation of deep peat layers that had not previously been exposed to air, the so-called secondary decomposition. We incubated two types of peat (eutrophic and oligotrophic), sampled from permanently anoxic peat layers from nature reserves and agricultural peat meadows. Peat samples were incubated for thirteen weeks under anoxic conditions, but were exposed to air for one to eight weeks. The production of CO2 and CH4 was quantified as a proxy for decomposition; concentrations of soluble nutrients and phenolic compounds were also measured. The results showed that oxygenation led to a steep increase in the rate of decomposition, indicated by higher carbon loss rates during and after oxygenation compared to non-oxygenated samples. Carbon loss rates increased more for eutrophic peat (agricultural area: 352%, nature reserve: 182%) than for oligotrophic peat (83% and 159% respectively). Most peat samples investigated showed higher post-oxygenation CO2 and/or CH4 production compared to the anoxic pre-oxygenation period. This indicates that oxygenation stimulates decomposition, even after anoxic conditions have returned. Contrary to the enzymic latch theory, no effects of oxygenation on the concentrations of soluble or condensed phenolic compounds were detected. Soluble nutrient concentrations did not change due to oxygenation either. Noteworthy is the occurrence of pyrite mineralization and associated acidification in eutrophic peat. Thus, low summer water levels, for example due to climate change, should be avoided in order to limit exceptionally high decomposition rates and associated problems such as increasing subsidence rates, greenhouse gas emission, sulfate release and acidification. PMID:24583945

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

2014-05-15

167

Environmental Controls over Peat Accumulation in Arctic Alaska  

NASA Astrophysics Data System (ADS)

Wide spread accumulation of peat (paludification) began on Alaska's North Slope during the Pleistocene/Holocene transition starting ca. 12,000 14C years ago and established this region as a carbon sink. Its status as a C sink is in question today because of rapid climate change. Our project's focus is on the relationship between peat, microclimate, and topography in a portion of the Arctic Foothills 300-350 km south of Point Barrow on the northern flank of the Brooks Range. Our objectives are 1) Quantify how varying microclimate factors found along a climosequence determine the thickness of the thin surface peats (<50 cm) that have developed during the Holocene; 2) Estimate peat accumulation rates on level, initially well-drained geomorphic surfaces using a 3,000 year old chronosequence on river point bars; 3) Quantify how peat accumulation affects soil temperature regimes; 4) Develop a GIS-based peat-prediction model for a 50 km2 study area and estimate this area's pool of standing carbon. We used a combination of remotely sensed data, field measurements, and a GIS to gather data regarding slope, aspect, elevation, near-ground temperature, soil moisture, temperature at the organic/mineral horizon interface, solar radiation, upslope drainage area, and lastly, peat thickness. Peat is defined here as any near-surface soil horizon containing >25% organic carbon by volume. We employ statistical analyses to examine how each factor independently influences peat thickness and what suite of factors best explains peat distribution and thickness across the landscape. Results show a significant inverse relationship (R2 = 0.27, p-value <<.001) between slope and peat thickness, with an increase in steepness accompanying a decrease in peat thickness. There is a less significant relationship (R2 = 0.03, p-value = .02) between aspect and peat thickness. There is a significant positive relationship (R2 = 0.81, P-value <<.001) between peat thickness and July active layer thickness, indicating that peat thickness and below ground temperature regimes are highly correlated. We estimated time to paludification to be 300-600 years. Initial peat accumulation rates are 0.015 - 0.031 cm/yr (R2 = 0.56, P-value <<.001). There appears to be a temporal threshold along the chronosequence at approximately 400 years. After this point the peat accumulation rate is near zero and statistically insignificant (R2 = 0.02, P-value = 0.49). This could indicate that landscapes in the Arctic Foothills approach a stable state with regards to peat development rather quickly on the geologic time scale and challenges the idea of continuous peat accumulation. Results from this project will inform a geospatial model linking peat dynamics to climate change in arctic Alaska.

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

2012-12-01

168

Third technical contractors' conference on peat  

SciTech Connect

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)

Not Available

1981-01-01

169

Temperature and Microbial Activity Effects on Trace Element Leaching from Metalliferous Peats  

E-print Network

elements from soils into drainage water. Acidifi-the final leaching by measuring C mineralization followingH levels were cation, nitrogen fixation, and decomposition of organic between 2 and 4, with acidification-mediated the release of trace elements in both peat soils. Neutral M3 peat pH levels limited losses of most analytes

Walter, M.Todd

170

Microbial composition and diversity of an upland red soil under long-term fertilization treatments as revealed by culture-dependent and culture-independent approaches  

Microsoft Academic Search

Background, aim, and scope  Fertilization is an important agricultural practice for increasing crop yields. In order to maintain the soil sustainability,\\u000a it is important to monitor the effects of fertilizer applications on the shifts of soil microorganisms, which control the\\u000a cycling of many nutrients in the soil. Here, culture-dependent and culture-independent approaches were used to analyze the\\u000a soil bacterial and fungal

Ji-Zheng He; Yong Zheng; Cheng-Rong Chen; Yuan-Qiu He; Li-Mei Zhang

2008-01-01

171

Late Holocene land-use and vegetation dynamics in an upland karst region based on pollen and coprophilous fungal spore analyses: an example from the Burren, western Ireland  

Microsoft Academic Search

The late Holocene environmental history of two karstic uplands in the Burren, western Ireland is reconstructed. The palaeoecological\\u000a investigations focus on species-rich, upland plant communities of high biogeographic interest that include Sesleria-dominated grasslands and heath communities with Dryas octopetala, Arctostaphylos uva-ursi and Empetrum nigrum. Short monoliths taken from shallow peats were pollen analytically investigated. Particular attention was paid to non-pollen

Ingo Feeser; Michael O’Connell

2010-01-01

172

Fourth technical contractors' conference on peat  

SciTech Connect

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)

Not Available

1981-01-01

173

Examining the effect of pore size distribution and shape on flow through unsaturated peat using 3-D computed tomography  

Microsoft Academic Search

The hydraulic conductivity of unsaturated peat soils is controlled by the peat structure which affects the air-filled porosity, pore size distribution and shape. This study investigates how the size and shape of pores affects the flow of water through peat soils. In this study we used X-ray Computed Tomography (CT), at 45 µm resolution under 5 specific soil-water pressure head

F. Rezanezhad; W. L. Quinton; J. S. Price; D. Elrick; T. R. Elliot; R. J. Heck

2009-01-01

174

Fluvial entrainment of low density peat blocks (block carbon)  

NASA Astrophysics Data System (ADS)

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

Warburton, Jeff

2014-05-01

175

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

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.

Oberbauer, S.F. [Florida International Univ., Miami, FL (United States); Gillespie, C.T. [Vandenburg Air Force Base, CA (United States); Cheng, Weixin [Desert Research Inst., Reno, NV (United States)] [and others

1996-08-01

176

Micro-Scale Distribution and Speciation of Arsenic in Peat  

NASA Astrophysics Data System (ADS)

Organic soils and peaty sediments frequently show arsenic (As) enrichments that suggest a direct association of As with natural organic matter (NOM). We have recently studied the speciation of As in a naturally As-enriched minerotrophic peatland (Gola di Lago) located in Southern Switzerland using bulk X-ray absorption spectroscopy (XAS) [1]. These analyses revealed that in deep peat layers, characterized by stable reducing redox conditions, the entire As was coordinated in its trivalent oxidation state to sulfhydryl groups of NOM. In shallow peat layers, however, the suite of As species comprised organically bound As, As sulfides, and As sorbed to Fe(III)-oxyhydroxides. Here we employed micro-X-ray fluorescence (?-XRF) spectrometry combined with ?-XAS to explore the micrometer-scale distribution, speciation, and elemental correlations of As in the Gola di Lago peat. Undisturbed peat material (260-550 mg As/kg) was retrieved from depths

Langner-Hofmann, Peggy; Mikutta, Christian; Kretzschmar, Ruben

2013-04-01

177

The peats of Costa Rica  

SciTech Connect

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.

Thayer, G.R.

1991-01-01

178

Strength Matters: Resisting Erosion Across Upland Landscapes  

NASA Astrophysics Data System (ADS)

Soil-covered upland landscapes comprise a critical part of the habitable world and our understanding of their evolution as a function of different climatic, tectonic, and geologic regimes is important across a wide range of disciplines. Erosion laws, which help direct our study and drive our models of Earth surface processes are based on little field data. Soil production and transport play essential roles in controlling the spatial variation of soil depth and therefore hillslope hydrological processes, vegetation, and soil biological activity. Field-based confirmation of the hypothesized relationship between soil thickness and soil production is recent, however, and here we quantify the first direct physical explanation of variable soil production across landscapes. We report clear empirical linkages between the mechanical strength of the parent material (erodability), soil production rates determined from the same material, and the routing of water on hillslopes. Specifically, soil production rates determined from in situ produced 10Be and 26Al decrease exponentially with increasing shear strength of parent material across three very different field sites, all underlain by granitic bedrock: The Point Reyes Peninsular and The San Gabriel Mountains in California and the Nunnock River, Australia field site used for extensive previous work. At the same field sites, we use fallout radionuclide profiles to show how the flux of water across the soil-saprolite boundary changes significantly along the hillslope profile. Specifically, we quantify the transition from creep dominated bioturbation on the upper parts of the hillslopes to overland flow dominated surficial erosion towards the axis of the unchannelled swales. Our field-based data, collected across a full range of erosion and soil production rates and topographic settings, help explain more clearly the linkages between biota, weathering, hillslope hydrology, and the evolution of the Earth's surface.

Heimsath, A. M.

2012-12-01

179

Examining the Effect of Pore Size Distribution and Shape on Flow through Unsaturated Peat using Computer Tomography  

Microsoft Academic Search

The hydraulic conductivity of unsaturated peat soil is controlled by the air-filled porosity, pore size and geometric distribution as well as other physical properties of peat materials. This study investigates how the size and shape of pores affects the flow of water through peat soils. In this study we used X-ray Computed Tomography (CT), at 45?m resolution under 5 specific

Fereidoun Rezanezhad; William L. Quinton; Jonathan S. Price; David Elrick; T. R. Elliot; Richard J. Heck

2009-01-01

180

Differences between valley and upland vegetation development in eastern Noord-Brabant, The Netherlands, during the Late Glacial and early Holocene  

Microsoft Academic Search

Analysis of pollen, including the determination of pollen concentrations and of relative pollen values, macrofossil analysis of peat cores from oxbows in river valleys and of pingo melt holes on the upland, and the application of recent surface samples from northern Finland have enabled the establishment of two different lines of vegetational succession, one for the valley and another for

W. van Leeuwaarden; C. R. Janssen

1987-01-01

181

Cadmium in upland forests after vitality fertilization with wood ash—a summary of soil microbiological studies into the potential risk of cadmium release  

Microsoft Academic Search

The use of wood ash in forestry has been questioned because of the potential risk associated with its cadmium (Cd) content (1–30 mg kg ?1). In agriculture, wood ash is only allowed for use as a fertilizer when its Cd content is below 3 mg kg ?1. This restriction has not been applied to forest soils and there is a lack of

Jonna Perkiömäki; Hannu Fritze

2005-01-01

182

Towards a science of sustainable upland management in developing countries  

NASA Astrophysics Data System (ADS)

Farmers attempting to subsist in tropical uplands often rely upon unsustainable resource use practices that lead to soil erosion, declining crop yields, and a loss of soil productivity capacity. Other uses of tropical uplands, including logging and conversion of forest to rangelands, have similar results. The undesirable effects of these actions are felt on-site, at the watershed level, and even nationally. Ecological cause-effect relationships are poorly understood, and few examples exist of the successful integration of ecological knowledge with upland development. It is hypothesized that recent results of ecological research could be applied to uplands management so that stable sustainable systems of human use may be established. A second hypothesis is that statistically reliable data can be obtained from experiments in upland situations, although natural variations of soils, weather, and vegetation are great. To test these hypotheses, research involving multinational collaboration among American and Southeast Asian scientists has begun. The objective of the work is to provide credible quantitative information to help policy and decision makers and resident farmers to plan and implement improved practices based on ecological principles. Some findings to date include: 1. Ecological principles are difficult to relate to the practical context of upland agroecosystems. Indeed, the null hypothesis is necessary for planning experiments and demonstrations. 2. The “signal-to-noise” ratio in these field experiments is low, and the detection of changes due to human intervention in soil erosion, nutrient movement, and plant productivity is difficult. 3. Obstacles to field research in developing countries include logistic, cultural, political, and institutional factors. It is essential that local land managers participate from the start with scientific researchers in designing experiments. 4. Planned collaboration among academic and government scientists facilitates design of relevant research and the implementation of results. 5. The idea of ecologically based management has been well received by researchers and government officials in Asia. There is little argument with the logic of the approach. 6. Pressures for quick responses to urgent problems in the uplands conflict with the need for careful, long-term, statistically valid scientific research. 7. Ecological principles are vaguely understood and poorly articulated in the scientific literature. The transfer and application of ecological science to the developing world would be enhanced by clearer statements of principles.

Carpenter, Richard A.; Harper, David E.

1989-01-01

183

Physical and thermochemical properties of uncontaminated and diesel-contaminated peat  

SciTech Connect

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.

Ghaly, R.A.; Pyke, J.B.; Ghaly, A.E.; Ugursal, V.I. [Dalhousie Univ., Halifax, Nova Scotia (Canada)

1999-06-01

184

Some morphological and chemical aspects of peats applied to the characterization of histosols  

SciTech Connect

Five peats--Mesic Humisol (Hemic Medisaprist), a Fibric Mesisol (Fibric Medihemist), a Typic Mesisol (Typic Medihemist), and two Humic Mesisols (Sapric Medihemists)--were selected to include differences in landform, botanical composition and degree of decomposition. Special attention was devoted to the nonhumic fraction, especially the particle-size fractions. The peats and peat fractions were characterized according to their chemical and morphological features, to gain information useful in peat differentiation and interpretation. The results indicate that the evaluation of the peats through the various parameters was in line with that obtained by the rubbed fiber content and the P/sub 2/O/sub 7/ index, two conventional and widely accepted criteria for peat characterization. However, the additional information gained through the micromorphological measurements, determinations on size fractions and examination of macrofossils could be used efficiently in differentiating poorly characterized peat soils (Mesisols) and in determining the behavior of peats under cultivation. It was concluded that micromorphological measurements, particle-size distribution, and macrofossil analysis of size fractions can be used in support of commonly used criteria for differentiating peats; in addition, they provide an essential basis for peat interpretation. (JMT)

Levesque, M.P.; Dinel, H.

1982-05-01

185

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

USGS Publications Warehouse

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

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

2009-01-01

186

Biochemical processes of oligotrophic peat deposits of Vasyugan Mire  

NASA Astrophysics Data System (ADS)

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

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

2009-04-01

187

Calibration of Time Domain Reflectometry Using Undisturbed Peat Samples  

NASA Astrophysics Data System (ADS)

At present, freeze-thaw experiments on 60 cm diameter by 90 cm deep peat/permafrost cores from our central Mackenzie River basin long-term field site are being conducted to better elucidate coupled heat and moisture transport processes occurring in the active layer. Time domain reflectometry (TDR) along with 15 cm and 30 cm probes is being used to monitor the depth-specific volumetric soil moisture (VSM) in these cores. Organic soils are characterized by high porosities and soil density increases many folds at successive depths. Therefore, we calibrated the TDR for different depths and for peat with two different origins (sphagnum moss and lichen). A simple apparatus was developed to ensure a more homogenous soil moisture distribution in the undisturbed samples used for calibration. Methodology and results for the calibration as well as comparisons with mixing models at different densities are presented and the effects of different soil phases on calibration are discussed.

Nagare, R. M.; Schincariol, R. A.; Quinton, W. L.; Hayashi, M.

2009-05-01

188

Slagging behaviour of peat ash  

SciTech Connect

The use of peat for energy production in Finland dates back to early 1970`s. For the present, the peat combustion is responsible for over 5% of the energy production in Finland. Many of the major Finnish power plants still use pulverized fuel, but the utilization of fluidized bed boilers is rapidly increasing. Boilers of this type are best suited for fuel with a low energy value because the increased efficiency is beneficial for the community heat distribution. The Toppila power plant of Oulu Energy Company in the city of Oulu, Finland has two units. The older one, Toppila I, is a 250 MW boiler using pulverized peat as fuel. The new Toppila II boiler is a 310 MW circulating fluidized bed boiler. The power plant uses 15 000 m{sup 3} of peat per day with full load. The stagging behavior of peat ash varies depending on the bog peat is ogirinating. The plant shutdown because of extensive stagging may cause significant economical losses in the entire chain of energy production. Therefore the stagging behaviour of peat ash needs to be predicted already from peat prior to its combustion.

Heikkinen, R.; Laitinen, R.S.; Patrikainen, T.; Tiainen, T. [Univ. of Oulu (Finland)] [and others

1996-12-31

189

7 CFR 1205.13 - Upland cotton.  

...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...

2014-01-01

190

7 CFR 1205.13 - Upland cotton.  

Code of Federal Regulations, 2013 CFR

...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...

2013-01-01

191

7 CFR 1205.13 - Upland cotton.  

Code of Federal Regulations, 2012 CFR

...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...

2012-01-01

192

7 CFR 1205.13 - Upland cotton.  

Code of Federal Regulations, 2010 CFR

...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...

2010-01-01

193

7 CFR 1205.13 - Upland cotton.  

Code of Federal Regulations, 2011 CFR

...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...

2011-01-01

194

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

195

Guidance on peat soils 1 | Peat | Helen Cariss  

E-print Network

with the UK Woodland Assurance Standard Background There is a strong policy presumption against permanent and woodlands, Woodlands for Wales the revised UK Forest Standard and Guidelines and to be compatible restoration. The test is whether restoration can successfully be achieved in a reasonable timescale

196

Northern Bobwhite and Lead Shot Deposition in an Upland Habitat  

Microsoft Academic Search

We estimated total lead shotshell pellets expended, resultant pellet availability near soil surface, and the frequency of\\u000a pellet ingestion by northern bobwhites (Colinus virginianus) attributable to nearly a quarter century of bobwhite hunting on a 202-ha upland habitat at Tall Timbers Research Station,\\u000a Leon County, Florida. A total of 7,776 shots were fired, resulting in the expenditure of approximately 4.5

M. K. Keel; W. R. Davidson; G. L. Doster; L. A. Lewis

2002-01-01

197

The peats of Costa Rica  

SciTech Connect

The authors compare the competitive position of peat for energy with coal, oil, and cogenerative systems in gasifiers and solid-fuel boilers. They also explore the possibility for peat use in industry. To identify the major factors, they analyze costs using a Los Alamos levelized cost code, and they study parametric costs, comparing peat production in constant dollars with interest rates and return on investment. They consider costs of processing plant construction, sizes and kinds of boilers, retrofitting, peat drying, and mining methods. They examine mining requirements for Moin, Changuinola, and El Cairo and review wet mining and dewatering methods. Peat can, indeed, be competitive with other energy sources, but this depends on the ratio of fuel costs to boiler costs. This ratio is nearly constant in comparison with cogeneration in a steam-only production system. For grate boilers using Costa Rican high-ash peat, and for small nonautomatic boilers now used in Costa Rica, the authors recommend combustion tests. An appendix contains a preliminary mining plan and cost estimate for the El Cairo peat deposit. 8 refs., 43 figs., 19 tabs.

Thayer, G.R.; Williamson, K.D. Jr. (Los Alamos National Lab., NM (USA)); Ramirez, O. (RECOPE, San Jose (Costa Rica))

1991-04-01

198

Second technical contractors' conference on peat  

SciTech Connect

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)

Not Available

1980-01-01

199

Age Determination of the Remaining Peat in the Sacramento-San Joaquin Delta, California, USA  

USGS Publications Warehouse

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.

Drexler, Judith Z.; de Fontaine, Christian S.; Knifong, Donna L.

2007-01-01

200

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

NASA Astrophysics Data System (ADS)

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

Clay, Gareth; Worrall, Fred; Masiello, Carrie

2013-04-01

201

Peat as an energy alternative  

SciTech Connect

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

Punwani, D.V.

1980-07-01

202

Dewatering Peat With Activated Carbon  

NASA Technical Reports Server (NTRS)

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.

Rohatgi, N. K.

1984-01-01

203

Revegetation processes and environmental conditions in abandoned peat production fields in Estonia  

NASA Astrophysics Data System (ADS)

As a result of peat extraction, peat production has been finished in Estonia at different times in 154 peat production areas and 9,500 ha (~1% of peatlands) are abandoned, although the peat reserves are not exhausted yet; besides, several areas are not properly recultivated. In addition 12,000 ha of fens (oligotrophic peat layers) are drained and used as grasslands. If the abandoned and non-recultivated peat production areas are not vegetated, their CO2 emission is considerable and peat mineralises in such areas. The aim of the study was to find out specific ecological and geological factors, which affect recovering of peatlands and influence the recultivation. During the revision the amount and quality of the remained reserves, as well as the state of water regime, drainage network and revegetation was assessed in all 154 abandoned peat production areas. The study showed that the state of them is very variable. Some of them are covered with forest, prevailingly with birches at former drainage ditches, later supplemented by pine trees. In the others predominate grasses among plants, and various species of moss (Cladonia rei, Bryum caespiticum, Sphagnum ripariuma, Sphagnum squarrosum) occur as well. Besides, some abandoned areas are completely overgrown with cotton grass. Open abandoned peat areas, which are not covered by vegetation, are much rarer. We found out, that water regime among the factors plays most important role. Moreover abandoned peat production fields, where the environmental conditions have changed - are appropriate for growth of several moss species, which cannot inhabit the areas already occupied by other species. The most interesting discovers were: second growing site of Polia elongata in West-Estonia and Ephemerum serratum, last found in Estonia in the middle of the 19th century, was identified in central Estonia. Also Campylopus introflexus, what was unknown in Estonia. However, the changes in environmental conditions influence the peat layers structure and technical characteristics of organic soils that affect the vegetation of peatlands.

Orru, M.; Orru, H.

2009-04-01

204

A new model for studying the impacts of land cover change on flood hydrographs in upland peatland catchments  

NASA Astrophysics Data System (ADS)

There is global concern about headwater management and associated impacts on river flow. In many wet temperate zones peatlands can be found in headwater catchments. In the UK there is major concern about how environmental change, driven by human interventions, has altered the surface cover of headwater blanket peatlands. However, the impact of such cover changes on river flow is poorly understood. In particular, there is poor understanding of the how different spatial configurations of vegetation impact on the management of river flow peaks in upland catchments. This paper employs a numerical modelling approach to explore such impacts. TOPMODEL, due to its process representation which is very suitable for blanket peat catchments, was utilized as a prototype acting as the basis for a new distributed catchment hydrological model. The new model is totally distributed with a computational unit of a grid cell. The core equations representing subsurface flow in the original TOPMODEL were inherited by the distributed version of TOPMODEL and downscaled from the catchment level to the cell level for the transformation to the distributed model. The downscaled equations constitute the main part of the subsurface flow module and the runoff produced by each cell is obtained by partitioning rainfall between evapotranspiration, subsurface flow and saturation-excess overland flow in the extended model. A new overland flow module with a set of stochastic algorithms for overland flow transport was created to simulate overland flow movement, in which the overland flow produced in each cell is treated as many parcels (e.g. 100 parcels) of water. The flow velocity is calculated by the local slope, the overland flow depth, and the land surface roughness (associated with land cover types) based on empirical data. For each parcel the direction and distance of its movement in a single time step is obtained as a stochastic process, based on the partition of flow between downslope directions and the average flow velocity, interpreted as a probability of stopping in each cell traversed. This module also include a re-infiltration mechanism in which the overland flow yielded in upslope cells can infiltrate into the unsaturated soil in downslope cells to contribute to subsurface flow produced in these cells. This rarely considered mechanism in hydrological models shows one important way in which the real process of overland flow generation on hillslopes may be influenced by land cover. This significant new advance may have wide applicability, and there is only one new key parameter (overland flow velocity parameter) which replaces the constant overland flow velocity in the original TOPMODEL, limiting the possibilities of over-parameterization. The new model was tested in three upland peat catchments in different parts of the UK: Trout Beck in the North Pennines, the Wye in mid-Wales and the East Dart in southwest England. The model was found to work well in all three cases, and could be employed in future land cover scenario studies concerning impacts of land cover change on river flow in upland peatlands.

Gao, Jihui; Kirkby, Mike; Holden, Joseph

2014-05-01

205

7 CFR 1427.101 - Eligible upland cotton.  

Code of Federal Regulations, 2011 CFR

...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...

2011-01-01

206

7 CFR 1427.103 - Upland cotton Domestic User Agreement.  

...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...

2014-01-01

207

7 CFR 1427.103 - Upland cotton Domestic User Agreement.  

Code of Federal Regulations, 2013 CFR

...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...

2013-01-01

208

7 CFR 1427.101 - Eligible upland cotton.  

...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...

2014-01-01

209

7 CFR 1427.103 - Upland cotton Domestic User Agreement.  

Code of Federal Regulations, 2011 CFR

...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...

2011-01-01

210

7 CFR 1427.101 - Eligible upland cotton.  

Code of Federal Regulations, 2013 CFR

...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...

2013-01-01

211

7 CFR 1427.103 - Upland cotton Domestic User Agreement.  

Code of Federal Regulations, 2012 CFR

...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...

2012-01-01

212

7 CFR 1427.101 - Eligible upland cotton.  

Code of Federal Regulations, 2012 CFR

...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...

2012-01-01

213

Measurements of CO2 exchange with an automated chamber system throughout the year: challenges in measuring night-time respiration on porous peat soil  

NASA Astrophysics Data System (ADS)

We built an automatic chamber system to measure greenhouse gas (GHG) exchange in forested peatland ecosystems. We aimed to build a system robust enough which would work throughout the year and could measure through a changing snowpack in addition to producing annual GHG fluxes by integrating the measurements without the need of using models. The system worked rather well throughout the year, but it was not service free. Gap filling of data was still necessary. We observed problems in carbon dioxide (CO2) respiration flux estimation during calm summer nights, when a CO2 concentration gradient from soil/moss system to atmosphere builds up. Chambers greatly overestimated the night-time respiration. This was due to the disturbance caused by the chamber to the soil-moss CO2 gradient and consequent initial pulse of CO2 to the chamber headspace. We tested different flux calculation and measurement methods to solve this problem. The estimated flux was strongly dependent on (1) the starting point of the fit after closing the chamber, (2) the length of the fit, (3) the type of the fit (linear and polynomial), (4) the speed of the fan mixing the air inside the chamber, and (5) atmospheric turbulence (friction velocity, u*). The best fitting method (the most robust, least random variation) for respiration measurements on our sites was linear fitting with the period of 120-240 s after chamber closure. Furthermore, the fan should be adjusted to spin at minimum speed to avoid the pulse-effect, but it should be kept on to ensure mixing. If night-time problems cannot be solved, emissions can be estimated using daytime data from opaque chambers.

Koskinen, M.; Minkkinen, K.; Ojanen, P.; Kämäräinen, M.; Laurila, T.; Lohila, A.

2014-01-01

214

Measurements of CO2 exchange with an automated chamber system throughout the year: challenges in measuring nighttime respiration on porous peat soil  

NASA Astrophysics Data System (ADS)

We built an automatic chamber system to measure greehouse gas (GHG) exchange in forested peatland ecosystems. We aimed to build a system robust enough which would work throughout the year and could measure through a changing snowpackin addition to producing annual GHG fluxes by integrating the measurements without the need of using models. The system worked rather well throughout the year, but it was not service free. Gap filling of data was still necessary. We observed problems in carbon dioxide (CO2) flux estimation during calm summer nights, when a CO2 concentration gradient from soil/moss system to atmosphere builds up. Chambers greatly overestimated the nighttime respiration. This was due to the disturbance caused by the chamber to the soil-moss CO2 gradient and consequent initial pulse of CO2 to the chamber headspace. We tested different flux calculation and measurement methods to solve this problem. The estimated flux was strongly dependent on (1) the type of the fit (linear and polynomial), (2) the starting point of the fit after closing the chamber, (3) the length of the fit, (4) the speed of the fan mixing the air inside the chamber, and (5) atmospheric turbulence (friction velocity, u*). The best fitting method (the most robust, least random variation) was linear fitting with the period of 120-240 s after chamber closure. Furthermore, the fan should be adjusted to spin at minimum speed to avoid the pulse-effect, but it should be kept on to ensure mixing. If nighttime problems cannot be solved, emissions can be estimated using daytime data from opaque chambers.

Koskinen, M.; Minkkinen, K.; Ojanen, P.; Kämäräinen, M.; Laurila, T.; Lohila, A.

2013-08-01

215

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

NASA Astrophysics Data System (ADS)

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.

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

2010-05-01

216

Northern bobwhite and lead shot deposition in an upland habitat.  

PubMed

We estimated total lead shotshell pellets expended, resultant pellet availability near soil surface, and the frequency of pellet ingestion by northern bobwhites ( Colinus virginianus) attributable to nearly a quarter century of bobwhite hunting on a 202-ha upland habitat at Tall Timbers Research Station, Leon County, Florida. A total of 7776 shots were fired, resulting in the expenditure of approximately 4.5 million pellets (approximately 22519/ha). Sixteen of 235 (6.8%) soil samples collected in 1989 and 1992 contained one or two pellets. Soil samples indicated that approximately 7800 pellets/ha (about 35% of the projected 24-year deposition) were within 2.54 cm of the soil surface. Pellet ingestion by bobwhites was evaluated by examining 241 gizzards collected from 1989-92. Three bobwhites (1.3%) had ingested pellets ( x = 1.3 pellets). No instances of suspected lead poisoning were noted in bobwhites over the 24-year period. Sport hunting of wild bobwhite populations on upland habitats appears to produce a low potential for lead poisoning compared to lead deposition in association with waterfowl and dove hunting. PMID:12202928

Keel, M K; Davidson, W R; Doster, G L; Lewis, L A

2002-10-01

217

Metal removal from wastewater using peat  

Microsoft Academic Search

Peat has been investigated by several researchers as a sorbent for the capture of dissolved metals from wastestreams. Besides being plentiful and inexpensive, peat possesses several characteristics that make it an effective media for the removal of dissolved metal pollutants. The mechanism of metal ion binding to peat remains a controversial area with ion-exchange, complexation, and surface adsorption being the

P. A Brown; S. A Gill; S. J Allen

2000-01-01

218

Mineralization of 13C glucose in three fine textured soils from the western boreal forest  

NASA Astrophysics Data System (ADS)

Microbial composition is known, on similar soil types, to vary based on differing organic matter inputs, or stand composition. Dominating western upland boreal forests are fine textured soils with a canopy cover of aspen (Populus tremuloides Michx.), white spruce (Picea glauca (Moench) Voss or a mixture of the two. These soils then reflect different belowground biogeochemical processing of organic matter. Anthropogenic soils, formed from a combination of peat litter and fine textured mineral soil, are now also a part of the landscape in the western boreal. This study set out to determine if a simple labelled compound (13C glucose) was processed differently between soils from the two dominant stand types (aspen and spruce) and a soil from an anthropogenic (constructed) site. Results indicate that while all three soils rapidly incorporated, and respired, the labelled carbon each maintained a distinct microbial community structure (as evidenced by phospholipid fatty acid analysis) throughout the 300 hour experiment. Therefore soils with different microbial communities from varied organic matter inputs decompose organic carbon by different processes, even in the case of simple labile compounds.

Norris, C. E.; Quideau, S. A.; Macey, D. E.

2012-04-01

219

Experimental evidence for mobility/immobility of metals in peat.  

PubMed

The biogeochemical cycles of most toxic metals have been significantly altered by anthropogenic activities. Anaerobic, rain-fed organic soils are believed to record historical changes in atmospheric pollution. Suspected postdepositional mobility of trace elements, however, hinders the usefulness of peat bogs as pollution archives. To lower this uncertainty, we quantified the mobility of six trace metals in peat during an 18-month field manipulation. A replicated, reciprocal peat transplant experiment was conducted between a heavily polluted and a relatively unpolluted peatland, located 200 km apart in the Czech Republic (Central Europe). Both peatlands were Sphagnum-derived, lawn-dominated, and had water table close to the surface. A strikingly different behavior was observed for two groups of elements. Elements of group I, Fe and Mn, adjusted their abundances and vertical patterns to the host site, showing an extremely high degree of mobility. In contrast, elements of group II, Pb, Cu, Zn, and Ti, preserved their original vertical patterns at the host site, showing a high degree of immobility. Our experimental results suggest that not just lead, but also copper and zinc concentration profiles in peat are a reliable archive of temporal pollution changes within a wide pH range (2.5-5.8). PMID:21761934

Novak, Martin; Zemanova, Leona; Voldrichova, Petra; Stepanova, Marketa; Adamova, Marie; Pacherova, Petra; Komarek, Arnost; Krachler, Michael; Prechova, Eva

2011-09-01

220

Ecological study of peat landforms in Canada and Alaska  

NASA Technical Reports Server (NTRS)

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.

Glaser, Paul H.

1989-01-01

221

Abstract, International Applied Geochemistry Symposium, 2009 Peat groundwater as a medium for surficial geochemical exploration  

E-print Network

of electrical conductivity, CaCO3 saturation index, Ca, and alkalinity indicate groundwater upwelling. Upwelling). These models have focused on identification of geochemical responses in soil. In many northern regions, peat, and there are specific geochemical responses that are not shared with soil geochemical exploration. GEOLOGICAL SETTING

222

Stabilization of Peat by Deep Mixing Method: A Critical Review of the State of Practice  

Microsoft Academic Search

The purpose of this paper is to advance the knowledge on peat soil stabilization by critically examining and documenting the current state of practice. Deep Mixing method is emphasised on column type techniques using lime\\/cement. This paper is essentially a comprehensive review of available academic literature on deep soil stabilization utilizing this approach. Deep mixing with lime or lime-cement column

Shahidul Islam; Roslan Hashim

223

Elevated methane concentrations in trees of an upland forest  

NASA Astrophysics Data System (ADS)

There is intense debate about whether terrestrial vegetation contributes substantially to global methane emissions. Although trees may act as a conduit for methane release from soils to atmosphere, the debate centers on whether vegetation directly produces methane by an uncharacterized, abiotic mechanism. A second mechanism of direct methane production in plants occurs when methanogens - microorganisms in the domain Archaea - colonize the wood of living trees. In the debate this biotic mechanism has largely been ignored, yet conditions that promote anaerobic activity in living wood, and hence potentially methane production, are prevalent across forests. We find average, growing season, trunk-gas methane concentrations >15,000 ?L·L-1 in common, temperate-forest species. In upland habitat (where soils are not a significant methane source), concentrations are 2.3-times greater than in lowland areas, and wood cores produce methane in anaerobic, lab-assays. Emission rate estimates from our upland site are 52 ± 9.5 ng CH4 m-2 s-1; rates that are of a similar magnitude to the soil methane sink in temperate forest, and equivalent in global warming potential to ˜18% of the carbon likely sequestered by this forest. Microbial infection of one of the largest, biogenic sinks for carbon dioxide, living trees, might result in substantial, biogenic production of methane.

Covey, Kristofer R.; Wood, Stephen A.; Warren, Robert J., II; Lee, Xuhui; Bradford, Mark A.

2012-08-01

224

Landscape planning in areas of sand extraction in the Silesian Upland, Poland  

Microsoft Academic Search

In the Silesian Upland, sand has been used as fill material in coal mines for over a 100 years. Sand extraction has significantly transformed the geological structure, relief, water and soil conditions, vegetal cover, and microclimate. The aim of the following paper is a synthesis of anthropogenic transformation of the environment, shaping the landscape and restoring nature in areas of

Renata Dulias

2010-01-01

225

Thermal degradation of diesel-contaminated peats in an air atmosphere  

SciTech Connect

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.

Ghaly, R.A.; Ugursal, V.I.; Ghaly, A.E.; Mansaray, K.G. [Dalhousie Univ., Halifax, Nova Scotia (Canada)

1999-06-01

226

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

NASA Astrophysics Data System (ADS)

For remediation of soils and purification of waters biosorbents might be considered as an prospective group of materials and amongst them peat have a special role due to low cost, biodegradability, high number of functional groups, well developed surface area and combination of hydrophilic/hydrophobic structural elements. We have demonstrated the possibilities to use peat and its thermal treatment products for oil sorption. Peat as an oil sorbent has poor buoyancy characteristics, relatively low oil sorption capacity and low hydrophobicity. However, thermal treatment (low-temperature pyrolysis and synthesis of peat-based active coal) helps to significantly improve its sorptive characteristics. The processes and structural changes taking place during low-temperature pyrolysis have been studied by means of IR spectroscopy, thermogravimetry and scanning electron microscopy. Peat can be used also as an efficient sorbent for sorption of metallic elements as it has been demonstrated on example of Tl+, Cu2+, Cr3+, however sorption capacity in respect to nonmetallic (anionic species) elements is low. To develop such application possibilities peat, peat modified with iron compounds, iron humates were prepared and tested for sorption of arsenic and phosphorous compounds in comparison with weakly basic anionites. The highest sorption capacity was observed when peat sorbents modified with iron compounds were used. Sorption of different arsenic speciation forms onto iron-modified peat sorbents was investigated as a function of pH and temperature. It was established that sorption capacity increases with a rise in temperature, and the calculation of sorption process thermodynamic parameters indicates the spontaneity of sorption process and its endothermic nature.

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

2013-04-01

227

7 CFR 1205.305 - Upland cotton.  

Code of Federal Regulations, 2012 CFR

...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...

2012-01-01

228

7 CFR 1205.305 - Upland cotton.  

Code of Federal Regulations, 2013 CFR

...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...

2013-01-01

229

7 CFR 1205.305 - Upland cotton.  

Code of Federal Regulations, 2011 CFR

...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...

2011-01-01

230

7 CFR 1205.305 - Upland cotton.  

...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...

2014-01-01

231

7 CFR 1205.305 - Upland cotton.  

Code of Federal Regulations, 2010 CFR

...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...

2010-01-01

232

Pore water chemistry in a disturbed and an undisturbed peat forests in Brunei Darussalam: Nutrient and carbon contents  

NASA Astrophysics Data System (ADS)

Tropical peat swamp forests in their natural state are important reservoir of biodiversity, carbon and water. However, they are rapidly vanishing due to agricultural conversion (mainly to oil palms), logging, drainage and fire. Peat swamp forests constitute an important contribution to global and regional biodiversity, providing an habitat to rare and threatened species. They encompass a sequence of forest types from the perimeter to the center of mildely elevated domes, and at our site in Brunei, are host to Shorea Albida trees (Anderson, 1983). They constitute a large terrestrial carbon reservoir (tropical peat soils contain up to 70 Pg C, which accounts for 20% of global peat soil carbon and 2% of the global soil carbon (Hirano et al., 2007)). In tropical peat swamp forests, the most important factors controling organic matter accumulation, as well as the biodiversity and structure of the forest, are hydrology and nutrients availability (Page et al., 1999). Study of pore water in peat swamp forest can provide key information on carbon cycle, including biomass production, organic matter decomposition and leaching of carbon in draining water. However, data on pore water chemistry and nutrient concentrations in pristine tropical peatlands, as well as the effect of forest exploitation are scarce. The study area is located in the Belait district in Brunei Darussalam in Borneo Island. Brunei is perhaps the best of the regional guardians of peat forest systems; potentially irreversible damage to peat forest ecosystems has been widespread elsewhere. Two sites, one pristine dome and a logging concession, are being investigated. In order to assess the chemical status of the peat soil, pore water is sampled at different depth along the dome radius. The chemistry of pore water, including pH, conductivity, dissolved oxygen, concentration of major elements, as well as organic carbon content and properties are analyzed. References: Anderson, 1983. The tropical peat swamp of western malesia. Ecosystems of the world 4b, 181-189. Hirano et al., 2007. Carbon dioxide balance of a tropical peat swamp forest in Kalimantan, Indonesia. Global Change Biology 13, 412-425. Page et al., 1999. Interdependance of peat and vegetation in a tropical peat swamp forest. Phil. Trans. R. Soc. Lond. 354, 1885-1897.

Gandois, L.; Cobb, A.; Abu Salim, K.; Chieng Hei, I.; Lim Biaw Leng, L.; Corlett, R.; Harvey, C.

2010-12-01

233

PwC's 3-Peat  

ERIC Educational Resources Information Center

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…

Freifeld, Lorri

2010-01-01

234

Genetic Differentiation Revealed by Selective Loci of Drought-Responding EST-SSRs between Upland and Lowland Rice in China  

PubMed Central

Upland and lowland rice (Oryza sativa L.) represent two of the most important rice ecotypes adapted to ago-ecosystems with contrasting soil-water conditions. Upland rice, domesticated in the water-limited environment, contains valuable drought-resistant characters that can be used in water-saving breeding. Knowledge about the divergence between upland and lowland rice will provide valuable cues for the evolution of drought-resistance in rice. Genetic differentiation between upland and lowland rice was explored by 47 Simple Sequence Repeats (SSRs) located in drought responding expressed sequence tags (ESTs) among 377 rice landraces. The morphological traits of drought-resistance were evaluated in the field experiments. Different outlier loci were detected in the japonica and indica subspecies, respectively. Considerable genetic differentiation between upland and lowland rice on these outlier loci was estimated in japonica (Fst?=?0.258) and indica (Fst?=?0.127). Furthermore, populations of the upland and lowland ecotypes were clustered separately on these outlier loci. A significant correlation between genetic distance matrices and the dissimilarity matrices of drought-resistant traits was determined, indicating a certain relationship between the upland-lowland rice differentiation and the drought-resistance. Divergent selections occur between upland and lowland rice on the drought-resistance as the Qsts of some drought-resistant traits are significantly higher than the neutral Fst. In addition, the upland- and lowland-preferable alleles responded differently among ecotypes or allelic types under osmotic stress. This shows the evolutionary signature of drought resistance at the gene expression level. The findings of this study can strengthen our understanding of the evolution of drought-resistance in rice with significant implications in the improvement of rice drought-resistance. PMID:25286109

Xia, Hui; Zheng, Xiaoguo; Chen, Liang; Gao, Huan; Yang, Hua; Long, Ping; Rong, Jun; Lu, Baorong; Li, Jiajia; Luo, Lijun

2014-01-01

235

Smouldering fires and environmental reconstructions using ombrotrophic peat cores  

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

236

Freshwater peat on the continental shelf  

USGS Publications Warehouse

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

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

1967-01-01

237

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

PubMed

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

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

2012-08-01

238

Microbial Communities in Long-Term Heavy Metal Contaminated Ombrotrophic Peats  

Microsoft Academic Search

High concentrations of heavy metals are known to be toxic to many soil organisms. The effects of long-term exposure to lower\\u000a levels of metals on the soil microbial community are, however, less well understood. The southern Pennines of the U.K. are\\u000a characterised by expanses of ombrotrophic peat soils that have experienced deposition of high levels of heavy metals since\\u000a the

Patricia E. Linton; Laura Shotbolt; Andrew D. Thomas

2007-01-01

239

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

NASA Astrophysics Data System (ADS)

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.

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

2010-05-01

240

Soil moisture controls on temperature sensitivity of soil organic carbon decomposition for a mesic grassland  

Microsoft Academic Search

We examined relationships between soil moisture and the temperature sensitivity of decomposition of labile soil organic carbon at a central North American grassland. For soils collected from shallow, xeric uplands, temperature sensitivity was greatest at intermediate soil moisture. For soils collected from the deeper, mesic lowlands, temperature sensitivity increased with increasing soil moisture. For example, lowland soils incubated at 75%

Joseph M. Craine; Theodore M. Gelderman

2011-01-01

241

Assessment of the peat resources of Florida, with a detailed survey of the northern everglades  

SciTech Connect

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.

Griffin, G.M.; Wieland, C.C.; Hood, L.Q.; Goode, R.W. III; Sawyer, R.K.; McNeill, D.F.

1982-01-01

242

Peat Formation Processes During the Past 7000 Years in the Sacramento San Joaquin Delta, California, USA  

NASA Astrophysics Data System (ADS)

The 1,400 km2 tidal marsh that formed during the Holocene in the Sacramento--San Joaquin Delta was largely drained for agriculture during the past 150 years. The remaining peat constitutes an archive of marsh formation processes and environmental conditions through the millennia. The goals of the REPEAT (Rates and Evolution of Peat Accretion through Time) project are to determine past rates and processes of peat accretion to benefit future wetland restoration efforts. Peat cores were collected across the Delta during 2005 from drained, farmed islands and from remnant, marsh islands in the Delta. Radiocarbon analyses of plant macrofossils were used to construct age models for vertical peat profiles. Peat began forming approximately 6,600 calibrated years before present (cal yr BP). Over the last 150 years, approximately 2/3 of the original peat thickness on the farmed islands has been lost because of land-surface subsidence. On the marsh islands, estimated rates of vertical accretion range from 0.06 to 0.53 cm yr-1. Mean rates of vertical accretion at the marshes suggest that three out of the four marsh sites are capable of keeping pace with current rates of sea-level rise. Bulk density, % OM (organic matter), % contribution of OM vs. inorganic matter (IM) to soil volume, and vertical accretion rates show considerable variability through the millennia. Some variability is associated with a period of high precipitation and freshwater discharge between approximately 4,000 to 2,000 yr BP. The hydrogeomorphic setting of marshes appears to largely control the amount of IM incorporated into peat through time. Sediment supply will likely determine whether remnant and restored tidal marshes can keep pace with future sea-level rise in the Delta.

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

2008-12-01

243

Effects of fertigation management on growth and photosynthesis of tomato plants grown in peat, rockwool and NFT  

Microsoft Academic Search

A greenhouse experiment was conducted to determine the effects of substrate, irrigation scheduling and nutrient solution electrical conductivity (EC) on plant growth and photosynthesis of tomato plants. The plants grown in peat-bags were irrigated by a potential evapotranspiration (PET) dependent irrigation system. The first peat-bag treatment (control) was irrigated when the soil water potential reached ?5 kPa. EC was fixed

Hui-lian Xu; Laurent Gauthier; André Gosselin

1995-01-01

244

Substitution of peat, fertiliser and manure by compost in hobby gardening: user surveys and case studies.  

PubMed

Four user surveys were performed at recycle centres (RCs) in the Municipalities of Aarhus and Copenhagen, Denmark, to get general information on compost use and to examine the substitution of peat, fertiliser and manure by compost in hobby gardening. The average driving distance between the users' households and the RCs was found to be 4.3 km and the average amount of compost picked up was estimated at 800 kg per compost user per year. The application layer of the compost varied (between 1 and 50 cm) depending on the type of use. The estimated substitution (given as a fraction of the compost users that substitute peat, fertiliser and manure with compost) was 22% for peat, 12% for fertiliser and 7% for manure (41% in total) from the survey in Aarhus (n=74). The estimate from the survey in Copenhagen (n=1832) was 19% for peat, 24% for fertiliser and 15% for manure (58% in total). This is the first time, to the authors' knowledge, that the substitution of peat, fertiliser and manure with compost has been assessed for application in hobby gardening. Six case studies were performed as home visits in addition to the Aarhus surveys. From the user surveys and the case studies it was obvious that the total substitution of peat, fertiliser and manure was not 100%, as is often assumed when assigning environmental credits to compost. It was more likely around 50% and thus there is great potential for improvement. It was indicated that compost was used for a lot of purposes in hobby gardening. Apart from substitution of peat, fertiliser and manure, compost was used to improve soil quality and as a filling material (as a substitute for soil). Benefits from these types of application are, however, difficult to assess and thereby quantify. PMID:20724134

Andersen, Jacob K; Christensen, Thomas H; Scheutz, Charlotte

2010-12-01

245

Examining the effect of pore size distribution and shape on flow through unsaturated peat using 3-D computed tomography  

NASA Astrophysics Data System (ADS)

The hydraulic conductivity of unsaturated peat soils is controlled by the peat structure which affects the air-filled porosity, pore size distribution and shape. This study investigates how the size and shape of pores affects the flow of water through peat soils. In this study we used X-ray Computed Tomography (CT), at 45 µm resolution under 5 specific soil-water pressure head levels to provide 3-D, high-resolution images that were used to detect the inner pore structure of peat samples under a changing water regime. Pore structure and configuration were found to be irregular, which affected the rate of water transmission through peat soils. The 3-D analysis suggested that pore distribution is dominated by a single large pore-space. At low pressure head, this single large air-filled pore imparted a more effective flowpath compared to smaller pores. Smaller pores were disconnected and the flowpath was more tortuous than in the single large air-filled pore, and their contribution to flow was negligible when the single large pore was active. We quantify the pore structure of peat soil that affects the hydraulic conductivity in the unsaturated condition, and demonstrate the validity of our estimation of peat unsaturated hydraulic conductivity by making a comparison with a standard permeameter-based method. Estimates of unsaturated hydraulic conductivities were made for the purpose of testing the sensitivity of pore shape and geometry parameters on the hydraulic properties of peats and how to evaluate the structure of the peat and its affects on parameterization. We also studied the ability to quantify these factors for different soil moisture contents in order to define how the factors controlling the shape coefficient vary with changes in soil water pressure head. The relation between measured and estimated unsaturated hydraulic conductivity at various heads shows that rapid initial drainage, that changes the air-filled pore properties, creates a sharp decline in hydraulic conductivity. This is because the large pores readily lose water, the peat rapidly becomes less conductive and the flow path among pores, more tortuous.

Rezanezhad, F.; Quinton, W. L.; Price, J. S.; Elrick, D.; Elliot, T. R.; Heck, R. J.

2009-05-01

246

Examining the effect of pore size distribution and shape on flow through unsaturated peat using computed tomography  

NASA Astrophysics Data System (ADS)

The hydraulic conductivity of unsaturated peat soil is controlled by the air-filled porosity, pore size and geometric distribution as well as other physical properties of peat materials. This study investigates how the size and shape of pores affects the flow of water through peat soils. In this study we used X-ray Computed Tomography (CT), at 45 ?m resolution under 5 specific soil-water pressure head levels to provide 3-D, high-resolution images that were used to detect the inner pore structure of peat samples under a changing water regime. Pore structure and configuration were found to be irregular, which affected the rate of water transmission through peat soils. The 3-D analysis suggested that pore distribution is dominated by a single large pore-space. At low pressure head, this single large air-filled pore imparted a more effective flowpath compared to smaller pores. Smaller pores were disconnected and the flowpath was more tortuous than in the single large air-filled pore, and their contribution to flow was negligible when the single large pore was active. We quantify the pore structure of peat soil that affects the hydraulic conductivity in the unsaturated condition, and demonstrate the validity of our estimation of peat unsaturated hydraulic conductivity by making a comparison with a standard permeameter-based method. Estimates of unsaturated hydraulic conductivities were made for the purpose of testing the sensitivity of pore shape and geometry parameters on the hydraulic properties of peats and how to evaluate the structure of the peat and its affects on parameterization. We also studied the ability to quantify these factors for different soil moisture contents in order to define how the factors controlling the shape coefficient vary with changes in soil water pressure head. The relation between measured and estimated unsaturated hydraulic conductivity at various heads shows that rapid initial drainage, that changes the air-filled pore properties, creates a sharp decline in hydraulic conductivity. This is because the large pores readily lose water, the peat rapidly becomes less conductive and the flow path among pores, more tortuous.

Rezanezhad, F.; Quinton, W. L.; Price, J. S.; Elrick, D.; Elliot, T. R.; Heck, R. J.

2009-10-01

247

Geochemistry of amino acids in some Florida peat accumulations—II. Amino acid distributions  

NASA Astrophysics Data System (ADS)

Distributions of amino acids in some Florida peats have been compared with distributions in plants living now at the surface of the peats and in surface litter. Quantitative determinations were made by gas chromatography of volatile derivatives of both protein and non-protein amino acids. The latter. found also in mineral soils, are believed to represent bacterial cell constituents and/or anabolites. ?,?-diaminopimelic acid, a constituent of the mureide complex of bacterial cell walls, was found in peats and surface litter, as were other acids believed in soil ecosystems to result from the living processes of microorganisms. The protein amino acids in peats do not show a distinctive signature of any particular kind of organism, but the nature and concentrations of the non-protein acids support the inference that the higher plant constituents are extensively re-worked and that essentially all of the amino acid material in peats is microbial in proximate origin. Thus microbial amino acids appear to be quite significant participants in the input to coalification.

Casagrande, Daniel J.; Given, P. H.

1980-10-01

248

Hydrological studies on blanket peat: the significance of the acrotelm-catotelm model  

Microsoft Academic Search

Summary 1 Runoff production in blanket peat catchments of the northern Pennine hills, UK was measured through monitoring and experimentation at the plot, hillslope and catchment scale. Water flow from soil pipes was measured in one of the study catchments and overland flow, throughflow and water table were measured in runoff plots; rainfall simu- lation and tension-infiltrometry provided information on

J. Holden; T. P. Burt

2003-01-01

249

Plant Species Anaerobiosis and DOC Dynamics in a Peat-Forming Wetland, New York State  

Microsoft Academic Search

We quantified spatial and temporal patterns of dissolved organic carbon (DOC) concentrations in the shallow peat soil of a freshwater wetland (located in central New York State) and correlated the patterns with anaerobiosis in roots of the dominant plant species. Sampling was stratified in zones dominated by: lakebank sedge (Carex lacustris), common cattail (Typha latifolia), purple loosestrife (Lythrum salicaria) or

J. B. Yavitt; C. J. Williams

2004-01-01

250

Peat Hydrolysate Medium Optimization for Pullulan Production  

PubMed Central

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

Boa, Jacques M.; LeDuy, Anh

1984-01-01

251

Flow through macropores of different size classes in blanket peat  

Microsoft Academic Search

Blanket peats are important source areas for runoff in many northern European headwaters. The upper peat layer (20 cm) is dominant in producing flow in blanket peat catchments. However, little information exists on the relative roles of different size classes of macropore in water movement in this upper peat layer. This study uses results from tension infiltrometer experiments to assess

Joseph Holden

2009-01-01

252

North American Upland Gamebird Management at Crossroads  

E-print Network

Department of Wildlife Humholdt State Uni,'ersity Arcata. Calijomia The future of North American gamebirdNorth American Upland Gamebird Management at Crossroads: Which Road Will We Take? R. J. Gutierrez management is at crossroads. North American quail and pheasant are declining throughout much of their ranges

Gutiérrez, R.J.

253

Mapping Upland Hardwood Site Quality and Productivity with GIS and FIA in the Blue Ridge of North Carolina  

Microsoft Academic Search

The forested ecosystems of the southern Appalachians are some of the most diverse in North America due to the variability in climate, soils, and geologic parent material coupled with the complex topography found throughout the region. These same characteristics cause stands of upland hardwoods to be extremely variable with regard to site quality and productivity. Site index has been the

Claudia A. Cotton; Stephen R. Prisley; Thomas R. Fox

254

Impacts of peatland restoration on dissolved carbon loss from eroded upland peatlands in the UK  

NASA Astrophysics Data System (ADS)

Upland blanket peatlands in the UK are severely degraded by extensive gully erosion. Large areas have experienced complete vegetation loss. In the last decade landscape scale approaches to the restoration of eroded and bare peat have been developed in the Peak District National Park in northern England. Bare peat is re-vegetated with a nurse crop of grasses established by the aerial application of lime, seed, and fertiliser. The approach has successfully re-vegetated large areas of eroded bog a nd has been shown to dramatically reduce particulate carbon losses in runoff. The impacts of the treatment on water quality and dissolved carbon loss have not previously been fully assessed. This paper reports results from a small catchment study assessing the impacts of restoration practice in the Peak District. Data from five small catchments are presented one re-vegetated, one intact and three eroded/bare catchments. Bi-weekly water samples have been taken from the catchments between January 2011 and February 2012 and during July 2012 two of the bare sites were treated with lime, seed, and fertiliser. The data show that there are significant spikes in nutrient flux post treatment and marked effects on dissolved carbon which include initial spikes in in DOC concentration but longer term reductions in DOC concentration. Monitoring is ongoing at these sites but the evidence to date points to at least a short term benefit in DOC flux reduction from this form of peatland restoration.

Evans, M.; Stimson, A.; Allott, T. E. H. A.; Holland, N.

2012-04-01

255

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

SciTech Connect

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.

Higgitt, D.L.; Rowan, J.S. (Lancaster Univ. (United Kingdom)); Walling, D.E. (Univ. of Exeter (United Kingdom))

1993-01-01

256

Seasonal variation of microbial ecology in hemlock soil of Tatachia Mountain, Taiwan  

Microsoft Academic Search

Background and Purpose: Forest soil microorganisms and fauna decompose the organic materials, and thus strongly influence the nutrient cycling of the ecosystem. Soil microorganisms also contribute to soil structure and soil fertility. In Taiwan, the microbial distributions of soils have only been determined in acidic soil, inorganic acidic soil, upland soil, alkaline soil and power plant areas. There are few

Shang-Shyng Yang; Shu-Hsien Tsai; Hsiao-Yun Fan; Chiun-Kai Yang; Wei-Lan Hung; Shine-Tsern Cho

2006-01-01

257

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

NASA Astrophysics Data System (ADS)

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.

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

2012-06-01

258

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

USGS Publications Warehouse

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.

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

2012-01-01

259

A Few Issues on the Peat Research in the Altai Mountains  

NASA Astrophysics Data System (ADS)

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.

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

2010-05-01

260

Sensitivity of Scottish Upland Moorland Podzols Derived from Sandstones and Quartzites to Acidification: the Potential Importance of the Mobile Anion Effect  

Microsoft Academic Search

Soil samples were collected from the main horizons of Scottish upland moorland podzols derived from quartzite or Devonian and Torridonian sandstones. The soils were subjected to routine chemical analysis and the results studied in relation to potential acidification effects of atmospheric deposition. Stronger correlations were observed for soil pHwater than for soil pH in CaCl2 with wet deposition fluxes of

Catherine C. White; Malcolm S. Cresser

1998-01-01

261

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

PubMed Central

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

Palmer, Katharina

2012-01-01

262

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

USGS Publications Warehouse

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.

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

2007-01-01

263

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

NASA Astrophysics Data System (ADS)

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.

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

264

How old is upland catchment water?  

NASA Astrophysics Data System (ADS)

Understanding the dynamics of water supply catchments is an essential part of water management. Upland catchments provide a continuous, reliable source of high quality water not only for some of the world's biggest cities, but also for agriculture and industry. Headwater streams control river flow in lowland agricultural basins as the majority of river discharge emerges from upland catchments. Many rivers are perennial and flow throughout the year, even during droughts. However, it is still unclear how reliable and continuous upland catchment water resources really are. Despite many efforts in upland catchment research, there is still little known about where the water is stored and how long it takes to travel through upper catchments. Resolving these questions is crucial to ensure that this resource is protected from changing land use and to estimate potential impacts from a changing climate. Previous research in this important area has been limited by existing measurement techniques. Knowledge to date has relied heavily on the use of variation in stable isotope signals to estimate the age and origin of water from upland catchments. The problem with relying on these measures is that as the water residence time increases, the variation in the stable isotope signal decreases. After a maximum period of four years, no variation can be detected This means that to date, the residence time in upland catchments is likely to have been vastly underestimated. Consequently, the proportion of water flow out of upland river catchments to the total river flow is also underestimated. Tritium (3H) combines directly with water molecules and enters the flow paths with the infiltrating water. Its half-life (12.32 years) makes it ideal to describe residence times in upper catchment reservoirs as it can theoretically measure water up to about 150 years old. The bomb pulse peak in the southern hemisphere was several orders of magnitude lower than in the northern hemisphere. Hence the Tritium activities in the southern hemisphere have long decayed down the natural background levels, which allows unique ages to be determined by single measurements. In this study major ion chemistry, stable isotopes and Tritium were determined at 2 locations and various stages of discharge (18 Tritium samples in between April 2013 and January 2014) in a first-order perennial stream draining a 7.3 km2 catchment in the Dandenong National Park, Melbourne, Australia. Even during major discharge event major ions and stable isotope data have little variation and Tritium activities remain low (1.4 to 1.8 TU) in comparison to local rainfall of ~ 3TU. Age estimations based on an exponential flow model are 15 to 25 years indicating that water draining from upland catchments is much older than we have previously estimated using stable isotopes.

Hofmann, Harald; Cartwright, Ian; Morgenstern, Uwe; Gilfedder, Benjamin

2014-05-01

265

Soils of Henderson, Hidalgo, Milam, Nacogdoches, Navarro, Wichita, Willacy and Victoria Counties.  

E-print Network

, Irving, Cahaba, and BienvilIe series. The flat stream bottoms include the Ochlo- ckonee, Bibb, Johnston, and Trinity series. The Blackland Prairie soils, which are calcareous, include the Sumter and Houston soils of the uplands and the Bell soils..., Irving, Cahaba, and BienvilIe series. The flat stream bottoms include the Ochlo- ckonee, Bibb, Johnston, and Trinity series. The Blackland Prairie soils, which are calcareous, include the Sumter and Houston soils of the uplands and the Bell soils...

Fraps, G. S. (George Stronach)

1933-01-01

266

Effects of tree shelterbelts on the hydrology of upland areas  

NASA Astrophysics Data System (ADS)

Recent large flood events in the UK have focused attention on the effects of agricultural intensification and de-intensification on flood risk. Possible detrimental factors for these floods are thought to be the degradation of soil structure through compaction from grazing animals and agricultural machinery; while possible ameliorating factors may be the re-introduction of natural landscape features such as woodland and wetlands. In order to address this issue in an upland setting a multi-scale experimental programme has been implemented at Pontbren, a sheep-farmed headwater catchment of the River Severn, UK. Primary aims are to develop understanding of the processes governing flood generation and the associated impacts of land management practices, and to bridge the gap between process understanding and ability to predict effects on downstream flooding. An integral component of this is to determine the role that native, broadleaf trees, planted as shelterbelts on intensively grazed pasture, may have in the reduction of flooding. Effects of trees on soil physical properties, soil moisture status and rainfall interception are investigated, including any ‘rain-shadow' and edge effects. Three ungrazed tree strips, plus one woodland edge, have been instrumented with clusters of tensiometers, plus throughfall and stemflow collectors. Soil moisture measurements have been made with a neutron probe, and tracer tests and permeameter tests have been carried out. Overland flow has been collected at one tree site. Comparisons of soil hydraulic properties show significant increases in saturated moisture content and hydraulic conductivity of soil under trees compared to adjacent improved pasture. These effects, combined with increased interception and water use by the trees, have led to differences in soil moisture, with the soil under the trees being considerably drier than that under the pasture. The results show seasonal variation. Dye tracer tests reveal preferential flow along living tree roots. Overland flow results show substantial differences in surface runoff between the grazed pasture and the ungrazed tree-planted area. The results suggest that these effects of land management can improve soil structure and reduce rapid runoff, with consequent implications for reducing flood hazard.

Solloway, I.; Frogbrook, Z. L.; Jackson, B. M.; Marshall, M. R.; McIntyre, N. M.; Reynolds, B.; Wheater, H. S.; Chell, J.; Christen, B.

2009-04-01

267

Quantification of upland thermokarst features with high resolution remote sensing  

NASA Astrophysics Data System (ADS)

Climate-induced changes to permafrost are altering high latitude landscapes in ways that could increase the vulnerability of the vast soil carbon pools of the region. Permafrost thaw is temporally dynamic and spatially heterogeneous because, in addition to the thickening of the active layer, localized thermokarst features form when ice-rich permafrost thaws and the ground subsides. Thermokarst produces a diversity of landforms and alters the physical environment in dynamic ways. To estimate potential changes to the carbon cycle it is imperative to quantify the size and distribution of thermokarst landforms. By performing a supervised classification on a high resolution IKONOS image, we detected and mapped small, irregular thermokarst features occurring within an upland watershed in discontinuous permafrost of Interior Alaska. We found that 12% of the Eight Mile Lake (EML) watershed has undergone thermokarst, predominantly in valleys where tussock tundra resides. About 35% of the 3.7 km2 tussock tundra class has likely transitioned to thermokarst. These landscape level changes created by permafrost thaw at EML have important implications for ecosystem carbon cycling because thermokarst features are forming in carbon-rich areas and are altering the hydrology in ways that increase seasonal thawing of the soil.

Belshe, E. F.; Schuur, E. A. G.; Grosse, G.

2013-09-01

268

Geophysical evidence for peat basin morphology and stratigraphic controls on vegetation observed in a Northern Peatland  

NASA Astrophysics Data System (ADS)

Vegetation patterns in peatlands suggest autogenic peatland development and hydrological processes are controlling factors in peatland evolution. These processes regulate vegetation ordination by influencing pH and nutrient availability at the peat surface. Geophysical studies in Caribou Bog, a 2200-hectare peatland in central Maine, indicate a close correlation between underlying geologic deposits and dominant vegetation type. The location of pools within the bog also appears to be related to subsurface geologic materials. Electrical resistivity imaging along a 1 km transect across the central unit of Caribou Bog resolved underlying lake sediment and glacio-marine clay thickness, as well as variability in depth to glacial till. Ground penetrating radar precisely defined the organic-rich lake sediment, the glacio-marine interface, and elevated till surfaces where peat thickness is less than 10 m. Direct verification of peat and lake sediment thickness, in addition to samples of the glacio-marine and till deposits, constrained the geophysical interpretation. Wooded heath (WH) interspersed with occasional Sphagnum lawn occurs where lake sediment and glacio-marine clay accumulation is thickest. Abrupt thinning of both layers (such that peat rests directly on till in places) correlates with a sharp transition to shrub heath dominated vegetation. A major open pool area located within the WH coincides with a localized sandy mineral soil-lake sediment contact at the base of the bog. The geophysical data suggest the underlying double basin system influences peatland development and dictates vegetation patterning. Limited groundwater elevation data suggest that sub-organic sediment stratigraphy mapped with geophysics regulates water levels at the peat surface, exerting a control on vegetation patterning. The major pool area, located between the basins, appears to reflect isolation of stagnant water at a point where peat development is incomplete and thus suggests that pools exist concurrent with peatland formation.

Comas, Xavier; Slater, Lee; Reeve, Andrew

2004-08-01

269

7 CFR 28.303 - Standards for length of staple for American upland cotton.  

... Standards for length of staple for American upland cotton. 28.303 Section... Standards for length of staple for American upland cotton. (a) Effective July...standards for the lengths of staple of American upland cotton shall be...

2014-01-01

270

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

SciTech Connect

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.

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

1985-05-01

271

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

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

272

Peat Resources of North Caroline. Quarterly Progress Report.  

National Technical Information Service (NTIS)

This is a progress report on the preparation of inventory of peat deposits in North Carolina. Peat deposits in North Carolina are of three main geologic types representing the accumulation of organic matter in: Pocosin, broad shallow depressions on uplift...

R. L. Ingram

1980-01-01

273

Lytic enzyme activity in peat is increased by substrate amendment with chitin: Implications for the control of Phytophthora fragariae in Fragaria vesca  

Microsoft Academic Search

Chitin is reported to stimulate mycorrhizas and antagonistic, lytic-enzyme producing soil microorganisms. Here mycorrhizal\\u000a and non-mycorrhizal strawberry (Fragaria vesca) plants were grown in peat growth-substrate and in peat amended with chitin (Suppressor™). Chitinase and cellulase activity\\u000a was determined and the plants were challenged by inoculation withPhytophthora fragariae, the causal agent of redcore disease. Disease resistance was only found in the

Susan M. Rafferty; John G. Murphy; Alan C. Cassells

2003-01-01

274

Changes in Upland Wildlife Habitat on Farmland in Illinois 1920-1987  

PubMed

/ 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.KEY WORDS: Upland wildlife; Habitat; Agriculture; Illinois PMID:9465139

Ribic; Warner; Mankin

1998-03-01

275

Quantifying Relative Rates of Upland and Bank Erosion Using Radionuclide Tracers in AN Agricultural Watershed  

NASA Astrophysics Data System (ADS)

Watershed evolution is governed by interactions between different earth surface processes that are mediated by water through precipitation and surface-subsurface flows. One key process affecting the evolution of watersheds is the movement of sediment. To evaluate the movement of sediment at the watershed scale, a common practice is to quantify sediment loads at the outlet of a system, i.e., develop a sediment budget. However, most sediment budgets at watershed outlets are net balances of different source areas. Different processes delivering sediment to streams and waterways include erosion of upland soils, collapse of channel banks, and resuspension of bed sediments. Distinguishing material from these different sources requires that each source sediment has a unique set of characteristics (or signature). Only by differentiating the source materials to the suspended sediment load of a stream can accurate measures of upland sediment delivery, bank erosion, and bed resuspension be determined. A simplified method to coarsely differentiate eroded surface soils and channel sediments to the suspended sediment load of a stream was used during single runoff events in a representative agricultural watershed of the US Midwest. The method utilized the activities of two naturally occurring radioisotopes, 7Be and 210Pbxs, as tracers and a simple two end-member mixing model. This model was applied to sediment loads calculated from different methods including discrete grab samples and continuous measurements. The proportion of eroded upland soils was high during the beginning stages of the events, while the channel became the dominant contributor to the suspended load near the peaks and on the falling limbs of the event hydrographs. The primary reason for this change in the dominant sediment source was that the upland source quickly became exhausted, as shown with clockwise hysteresis. Combining the quantitative suspended sediment measurements with the load partitioning analysis revealed that the majority of sediment (~60%) transported during the events was derived from the uplands, while the channel source contributed the remainder of sediment especially during the falling limbs of the hydrographs. These results compared favorably with estimates of bank erosion rates measured using traditional erosion pins and channel surveys, as well as automated photoelectric erosion pins.

Wilson, C. G.; Papanicolaou, T.; Denn, K. D.

2010-12-01

276

Hydrological Simulation of Runoff from Peat Harvesting Areas Using DRAINMOD  

NASA Astrophysics Data System (ADS)

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

Mohammadighavam, Shahram; Kløve, Bjørn

2014-05-01

277

Population and Upland Crop Production in Nang Rong, Thailand  

Microsoft Academic Search

This paper estimates village-level models of the effects of population variables on the area devoted to upland crop production in Nang Rong district, Thailand. The expansion of upland crops is part of the growth of market agriculture in Nang Rong, and a correlate of deforestation in this setting, The results show that population density (measured as density of village settlement)

Barbara Entwisle; Stephen J. Walsh; Ronald R. Rindfuss; Leah K. VanWey

2005-01-01

278

Upland landscapes in Britain and the 1992 CAP reforms  

Microsoft Academic Search

The impact of the Common Agricultural Policy (CAP) on the uplands of Great Britain is examined, with particular emphasis on open land characterized by large expanses of rough pasture and heath. Following much concern in the immediate post?war period about the incomes of hill farmers, the paper outlines how the upland problem has been redefined in recent years as an

Michael Winter; Peter Gaskell; Christopher Short

1998-01-01

279

VEGETATION ANALYSIS OF UPLAND BURREN GRASSLANDS OF CONSERVATION INTEREST  

Microsoft Academic Search

This study addresses the classification of grassland and heath communities found within the Burren uplands of Co. Clare and identifies threats to their integrity. Quadrats were taken on a range of sites, focusing on semi-natural, upland grassland and heath of conservation interest. Before analysis, the data set was divided into a heath group and a grassland group based on cover

Sharon Parr; Grace O'Donovan; Stephen Ward; John A. Finn

2009-01-01

280

SPILOGALE GRACILIS IN UPLAND FORESTS OF WESTERN WASHINGTON AND OREGON  

Microsoft Academic Search

During surveys of upland forests in the Tsuga heterophylla Zone in Washington and Oregon, 1986 to 1996, we caught 192 S. gracilis. In the Oregon Coast Range, more (85%) S. gracilis were caught in oldeilar to Coast Range old growth (P = 0.60) with no differences between seral stages (P = 0.74). No S. gracilis were caught in upland forests

ANDREW B. CAREY; JANET E. KERSHNER

1996-01-01

281

Downward migration of metalaxyl fungicide in creeping bentgrass sand lysimeters as affected by organic waste, peat and zeolite amendments  

Microsoft Academic Search

Metalaxyl is a fungicide used for control of Pythium spp. diseases in turfgrass. The downward migration of metalaxyl was studied in irrigated lysimeters containing a fine sandy loam soil alone or sand amended with composted brewery waste, composted sewage sludge, peat or zeolite by analysis of the fungicide in leachates collected up to 65 days post application. The Arkport sandy

A. Martin Petrovic; William C. Barrett; Inga-Mai Larsson-Kovach; Charlotte M. Reid; Donald J. Lisk

1998-01-01

282

Decomposition of rice residue in tropical soils  

Microsoft Academic Search

Nitrogen mineralization and immobilization of rice residue in Maahas clay soil under lowland and upland conditions were investigated by using N-labelled rice straw. The mineralization of residue-nitrogen was taking place even though the net mineralization was depressed by incorporation of rice residue.There were some significant differences in the pattern of nitrogen transformation between lowland and upland soil conditions. The nitrogen

Tadakatsu Yoneyama; Tomio Yoshida

1977-01-01

283

A S-isotope approach to determine the relative contribution of redox processes to net SO 4 export from upland, and wetland-dominated catchments  

NASA Astrophysics Data System (ADS)

Reoxidation of S stored in lowlands after summer droughts has been reported to be responsible for the excess SO 4 export observed in many catchments in south central Ontario. Stable S isotopes can be used to identify the source of SO 4 export in stream water, and are particularly well suited to evaluating zones of dissimilatory SO 4 reduction (DSR) and the contribution of oxidation of reduced S species to stream SO 4. The Plastic Lake-1 (PC1) stream drains an upland coniferous forest and then passes through a Sphagnum-dominated swamp before discharging to Plastic Lake. Measurements of SO 4 fluxes and isotope ratios were used to determine the source of net SO 4 export and the contribution of redox processes to S retention and export in the upland and wetland, respectively. Mass balance budgets for the years 1999/00 and 2000/01, which had comparatively wet summers, indicated that the upland part of the catchment consistently exported SO 4 in excess of bulk deposition inputs. In contrast, mass budget calculations for the swamp indicated a net retention of 3 and 2 g S-SO 4/m 2 of wetland area, in 1999/00 and 2000/01 respectively. Higher ? 34SO 4 ratios and lower SO 4 concentrations in the swamp outflow (average +8.6 ± 2.6‰; 1.5 ± 0.6 mg S-SO 4/L) compared to the inflow draining the upland (+5.4 ± 0.7‰; 2.4 ± 0.3 mg S-SO 4/L) indicated that DSR was at least partly responsible for net SO 4 retention in the swamp. Isotope values in upland stream water (+5.7 ± 0.7‰) were only slightly higher than values in bulk deposition (average +5.1 ± 0.6‰) and soil leachate (+4.4 ± 0.4‰) over the 2-year period of study. Similar ? 34SO 4 values in upland stream water compared to deposition and soil leachate, despite substantial variations in water table height in the streambed (92 cm), suggest that reoxidation of reduced sulphides is not an important contributor to SO 4 export from the upland. Rather, net SO 4 export from the upland subcatchment is likely due to net release from upland soil, and slight differences in ? 34SO 4 between bulk deposition and soil leachate are consistent with SO 4 release from organic S forms.

Eimers, M. C.; Dillon, P. J.; Schiff, S. L.

2004-09-01

284

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

NASA Astrophysics Data System (ADS)

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.

Rochefort, Line

2013-04-01

285

Seasonality in water, carbon, and nitrogen fluxes from an upland boreal catchment underlain by continuous permafrost  

NASA Astrophysics Data System (ADS)

The balance between runoff and catchment residence time is critical to the biogeochemical processing of carbon (C) and nitrogen (N) in boreal ecosystems. Whether C is mineralized in soils or flushed from catchments depends on hydrologic fluxes and has implications for ecosystem productivity and climate change feedbacks. By measuring water fluxes and organic matter concentrations, we hope to elucidate the hydrologic and biogeochemical processes controlling C fate and transport in an upland boreal catchment underlain by permafrost. To understand the seasonal dynamics of water, C, and N fluxes, we monitored soil moisture, water chemistry, stream and subsurface flow, and conducted five conservative tracer additions in an upland catchment in the Yukon River Basin, Alaska. Tracer was added to a 2nd - order stream draining the north-facing hillslope during varying flow regimes in the summers of 2008 and 2009. Synoptic sampling and transient storage modeling results were used to explore the dynamics between hydrologic flux, and organic matter biogeochemistry in the soils and streams of this watershed. Silty hillslope soils were typically unsaturated, indicating that flow occurs predominantly through shallow, organic soils. Seasonal increases in runoff coefficients and major ion concentrations indicate greater contact with mineral soils later in the season, providing evidence that there is some flow through thawing preferential flowpaths (ie. soil pipes and/or thermokarst features) in the silt. Stream dissolved organic carbon (DOC) and nitrate concentrations were proportional to discharge at all but the lowest flows, indicating that precipitation leaches material from organic soils and transports it from the catchment. Stream DOC and nitrate concentrations were lower than expected given in-stream transport and inflows, suggesting that biogeochemical reactions were occurring. These reactions were modeled as first order decay of DOC and nitrate concentrations, and decreased seasonally, despite the fact that DOC became more labile. We believe that this indicates decreased reaction potential in the deeper subsurface flowpaths that develop later in the season, precluding water/organic soil contact. Our results highlight the importance of small surface streams and preferential flowpaths to water, C, and N export in the frozen silt uplands of interior Alaska, and identify a seasonal trend that controls stream C and N loads. Such hydrologic data is critical to our understanding of C fate and transport and provides important insight relevant to predicting boreal ecosystem changes that will likely occur as the arctic becomes warmer and wetter.

Koch, J. C.; Striegl, R. G.; Runkel, R. L.; Ewing, S. A.; McKnight, D. M.

2010-12-01

286

Toxic gas emissions from the Kayseri peat deposit, central Anatolia, Turkey  

NASA Astrophysics Data System (ADS)

Toxic gases evolving from the soil in urbanized peatland regions constitute a serious hazard since buildings may be subject to the direct ingress of volatiles into the structures. Peat formed in swamp and rarely exposed to subaerial conditions has been associated with the development of the folded foreland of the Quaternary Kayseri pull-apart basin. The peat deposit is extensively urbanized but so far no studies have evaluated the extent of the ground gas hazard. In this paper, the geology, petrography and chemical variation of the Kayseri peat deposit have been studied in order to predict the public health risk from the land gases' behaviour, especially in soil gases. The main volatile species detected are methane (CH4), hydrogen sulphide (H2S) and carbon dioxide (CO2), all of which are highly toxic. The primary means of gas entry is directly from the ground through the floors, walls, and especially subsurface telephone cable pipes. Indoor vents emit 1000-70,000 ppm CH4, 330-49,000 ppm CO2 and 3.8-6.5 ppm H2S in soil and subsurface pipes; concentrations high enough to present an acute respiratory hazard to persons close to the vents.

?ener, Mehmet; Korkanç, Mustafa; Furkan ?ener, M.; Ya?ar Korkanç, Selma; Zafer Özgür, F.

2012-10-01

287

INFLUENCE OF PEAT ON FENTON OXIDATION  

EPA Science Inventory

A diagnostic probe was used to estimate the activity of Fenton-derived hydroxyl radicals (@OH), reaction kinetics, and oxidation efficiency in batch suspensions comprised of silica sand, crushed goethite ("-FeOOH) ore, peat, and H2O2 (0.13 mM). A simple method of kinetic analysi...

288

Feasibility of a peat biogasification process  

NASA Astrophysics Data System (ADS)

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

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

1980-07-01

289

Leaching of Metals from Peat Fly Ashes.  

National Technical Information Service (NTIS)

The aim of the study was to describe the long term impact from fly ash disposed on landfill. The quality of the leachate of three peat fly ashes and, as comparison on coal fly ash, was studied by using batch leaching tests, column leaching tests, and larg...

M. Wahlstroem, V. Pohjola

1987-01-01

290

CANADIAN PEAT HARVESTING AND THE ENVIRONMENT  

E-print Network

% recycled fibre, 10% post-consumer waste) Interior pages printed on 100% recycled paper Over 50% recycled la tourbe et l'environnement au Canada. Deuxième �dition. Cover printed on recycled paper (50 paper including 10% post-consumer fibre. M ­ an official mark of Environment Canada E #12;CANADIAN PEAT

Laval, Université

291

Equivalent weight of humic acid from peat  

USGS Publications Warehouse

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.

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

1960-01-01

292

Vyrmethane Method. Biogas Extraction from Peat Bogs.  

National Technical Information Service (NTIS)

The Vyrmethane Method is based on the principle that the naturally gaseous water in the peat is pumped up and degassed in a vacuum tank. The gas is then led off and the water recirculated to the bog. On the basis of experience gained in conjunction with a...

L. Brolin

1988-01-01

293

GAM & RF for 3D mapping of multinomial peat properties.  

NASA Astrophysics Data System (ADS)

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.

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

2013-04-01

294

Northern Hemisphere control of deglacial vegetation changes in the Rufiji uplands (Tanzania)  

NASA Astrophysics Data System (ADS)

In tropical Eastern Africa, vegetation distribution is largely controlled by regional hydrology which has varied over the past 20 000 years. Therefore, accurate reconstructions of past vegetation and hydrological changes are crucial to better understand climate variability in the tropical Eastern African region. Through high-resolution pollen records from a marine sediment core recovered offshore the Rufiji River, our data show significant shifts in pollen assemblages during the last deglaciation identifying, through respective changes in both upland and lowland vegetation, specific responses of plant communities to atmospheric (precipitation) and coastal (coastal dynamics/sea level changes) alterations. Specifically, an interval of maximum pollen representation of dry and open vegetation occurred during the Northern Hemisphere cold Heinrich event 1 (H1) suggesting the expansion of drier upland vegetation under arid conditions. This dry spell is followed by an interval in which forest and humid woodland expanded, indicating a hydrologic shift towards more humid conditions. Droughts during H1 and the return to humid conditions around ~14.8 kyr BP in the uplands are primarily attributed to latitudinal shifts of the Intertropical Convergence Zone (ITCZ) driven by high-latitude Northern Hemisphere climatic fluctuations. Additionally, our results show that the lowland vegetation, consisting of a well developed salt marshes and mangroves in a successional pattern typical for vegetation occurring in intertidal habitats, has responded mainly to local coastal dynamics related to marine inundation frequencies and soil salinity in the Rufiji Delta as well as the local moisture availability. Lowland vegetation shows a substantial expansion of mangrove trees after ~14.8 kyr BP suggesting also an increased moisture availability and river runoff in the coastal area. The results of this study highlight the de-coupled climatic and environmental processes to which the vegetation in the uplands and the Rufiji Delta has responded during the last deglaciation.

Bouimetarhan, I.; Dupont, L.; Kuhlmann, H.; Pätzold, J.; Prange, M.; Schefuß, E.; Zonneveld, K.

2014-09-01

295

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

NASA Astrophysics Data System (ADS)

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.

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

2013-12-01

296

The use of principle component analyses in characterising trace and major elemental distribution in a 55 kyr peat deposit in tropical Australia: Implications to paleoclimate  

NASA Astrophysics Data System (ADS)

The Lynch's Crater peat deposit in NE-Australia is a sensitive environmental archive located in the tropical Southern Hemisphere. This unique deposit illustrates that local and regional changes had a profound effect on the local Australian ecosystem over the past 55 kyr. To obtain a proxy of past climate changes, trace and major element geochemistry analyses were applied to a 13 m peat core from the crater. Principle component analysis (PCA) was used to identify the main factors that control elemental distribution in the peat and to add interpretative strength to the geochemical behavior of selected major and trace elements. For example, Sc, Al, Cu, and Pb were found to be related to increased erosion of the basin soils, and from this, several periods of significant flux from atmospheric input and/or terrigenous run-off were identified. Geochemically mobile elements during rock weathering and pedogenesis, such as Mg, Ca, and Sr helped to identify the peat ombrotrophic-minerotrophic boundary at ?1.5 m depth and offered important information about fluxes of these nutrients to the mire and their dynamics within the deposit. Arsenic and V comparisons between the peat record (high concentrations in some peat sections) and in local basin rocks (very low concentrations), suggested the presence of a long range, atmospheric dust source early in the formation of the mire. The Lynch's Crater peat record presents a continuous record of environmental change in tropical Australia and contributes new understanding to geochemical processes in peatlands.

Muller, Joanne; Kylander, Malin; Martinez-Cortizas, Antonio; Wüst, Raphael A. J.; Weiss, Dominik; Blake, Kevin; Coles, Barry; Garcia-Sanchez, Raquel

2008-01-01

297

Dro1, a major QTL involved in deep rooting of rice under upland field conditions.  

PubMed

Developing a deep root system is an important strategy for avoiding drought stress in rice. Using the 'basket' method, the ratio of deep rooting (RDR; the proportion of total roots that elongated through the basket bottom) was calculated to evaluate deep rooting. A new major quantitative trait locus (QTL) controlling RDR was detected on chromosome 9 by using 117 recombinant inbred lines (RILs) derived from a cross between the lowland cultivar IR64, with shallow rooting, and the upland cultivar Kinandang Patong (KP), with deep rooting. This QTL explained 66.6% of the total phenotypic variance in RDR in the RILs. A BC(2)F(3) line homozygous for the KP allele of the QTL had an RDR of 40.4%, compared with 2.6% for the homozygous IR64 allele. Fine mapping of this QTL was undertaken using eight BC(2)F(3) recombinant lines. The RDR QTL Dro1 (Deeper rooting 1) was mapped between the markers RM24393 and RM7424, which delimit a 608.4 kb interval in the reference cultivar Nipponbare. To clarify the influence of Dro1 in an upland field, the root distribution in different soil layers was quantified by means of core sampling. A line homozygous for the KP allele of Dro1 (Dro1-KP) and IR64 did not differ in root dry weight in the shallow soil layers (0-25 cm), but root dry weight of Dro1-KP in deep soil layers (25-50 cm) was significantly greater than that of IR64, suggesting that Dro1 plays a crucial role in increased deep rooting under upland field conditions. PMID:21212298

Uga, Yusaku; Okuno, Kazutoshi; Yano, Masahiro

2011-05-01

298

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

USGS Publications Warehouse

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.

Reynolds, Lindsay V.; Cooper, David J.

2011-01-01

299

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

Microsoft Academic Search

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

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

2010-01-01

300

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

NASA Astrophysics Data System (ADS)

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.

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

2010-05-01

301

Evaluating the quality of hydraulic conductivity estimates from piezometer slug tests in peat  

NASA Astrophysics Data System (ADS)

Although widely used in wetland hydrological studies, hydraulic conductivity (K) estimates from piezometer slug tests are often of questionable validity. Frequently, this is because insufficient attention is paid to the details of the test procedure. Further, in a potentially heterogeneous and anisotropic medium such as peat, the use of slug tests is prone to error. In this paper we address some of the methodological issues surrounding piezometer slug tests in peat. We compare slug test data with laboratory determinations of vertical and horizontal K obtained using a new method. Piezometers were installed at three depths in a floodplain fen peat in Norfolk, UK. Slug tests were initiated by both slug insertion and slug withdrawal, and repeat tests were conducted to examine the robustness of our K estimates. Most of the tests displayed departures from the log-linear model of Hvorslev, the form of departure being consistent with compressible soil behaviour. The results suggest that insertion tests gave similar results to those initiated by withdrawal. Repeat testing showed that withdrawal data, in particular, gave highly reproducible normalized responses that were independent of the initial head. Values for K estimated using the slug tests were in the range 1 × 10-4 to 1.6 × 10-3 cm s-1, which is towards the upper end of the range reported for peats generally. Laboratory tests yielded similar values of K to those obtained from the slug tests. Although the laboratory tests showed that the peat was anisotropic, the K values generated by slug testing proved relatively good estimates of both vertical and horizontal K.

Surridge, Ben W. J.; Baird, Andrew J.; Heathwaite, A. L.

2005-04-01

302

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

SciTech Connect

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.

Tfaily, Malak [Florida State University, Tallahassee; Cooper, Bill [Florida State University, Tallahassee; Kostka, [Georgia Institute of Technology, Atlanta; Chanton, Patrick R [ORNL; Schadt, Christopher Warren [ORNL; Hanson, Paul J [ORNL; Iversen, Colleen M [ORNL; Chanton, Jeff P [ORNL

2014-01-01

303

Organic matter transformation in the peat column at Marcell Experimental Forest: Humification and vertical stratification  

NASA Astrophysics Data System (ADS)

characterized peat decomposition at the Marcell Experimental Forest (MEF), Minnesota, USA, to a depth of 2 m to ascertain the underlying chemical changes using Fourier transform infrared (FT IR) and 13C nuclear magnetic resonance (NMR) spectroscopy) and related these changes to decomposition proxies C:N ratio, ?13C and ?15N, bulk density, and water content. FT IR determined that peat humification increased rapidly between 30 and 75 cm, indicating a highly reactive intermediate-depth zone consistent with changes in C:N ratio, ?13C and ?15N, bulk density, and water content. Peat decomposition at the MEF, especially in the intermediate-depth zone, is mainly characterized by preferential utilization of O-alkyl-C, carboxyl-C, and other oxygenated functionalities with a concomitant increase in the abundance of alkyl- and nitrogen-containing compounds. Below 75 cm, less change was observed but aromatic functionalities and lignin accumulated with depth. Significant correlations with humification indices, identified by FT IR spectroscopy, were found for C:N ratios. Incubation studies at 22°C revealed the highest methane production rates, greatest CH4:CO2 production ratios, and significant O-alkyl-C utilization within this 30 and 75 cm zone. Oxygen-containing functionalities, especially O-alkyl-C, appear to serve as excellent proxies for soil decomposition rate and should be a sensitive indicator of the response of the solid phase peat to increased temperatures caused by climate change and the field study manipulations that are planned to occur at this site. Radiocarbon signatures of microbial respiration products in deeper pore waters at the MEF resembled the signatures of more modern dissolved organic carbon rather than solid phase peat, indicating that recently photosynthesized organic matter fueled the bulk of subsurface microbial respiration. These results indicate that carbon cycling at depth at the MEF is not isolated from surface processes.

Tfaily, Malak M.; Cooper, William T.; Kostka, Joel E.; Chanton, Patrick R.; Schadt, Christopher W.; Hanson, Paul J.; Iversen, Colleen M.; Chanton, Jeffrey P.

2014-04-01

304

Beneath the Arctic Green: Have recent increases in plant production been offset by increases in soil decomposition?  

NASA Astrophysics Data System (ADS)

Observational and modeling studies suggest that boreal vegetation has undergone an increase in plant production and C uptake in recent decades, coincident with increases in regional air temperatures, atmospheric CO2 concentration, and fire/successional dynamics. In the North American boreal forest, wildfires have increased in extent, season length, and depth of burn, driving higher C emission from black spruce ecosystems. Meanwhile, responses in soil systems that dictate the net ecosystem carbon (C) balance are less well known, in part owing to problems with elucidating the relatively small signals of organic matter decomposition from the large C fluxes of gross primary production and ecosystem respiration. Here, we measured net C accumulation in soils from Interior Alaska using radiocarbon (14C), lead isotopes (210Pb), cesium isotopes (137Cs), and time sequences of forest regeneration (fire and thaw chronosequences). We use soil 14C and non-steady-state models to estimate turnover times for soil organic C. Over the past century, rates of soil C uptake based on upland chronosequences ranged from -20 to -30 g C/m2/yr, but regionally likely shifted toward a reduced sink or source of - 20 to + 10 g C/m2/yr in recent decades due to increased combustion losses and deep C mobilization associated with permafrost thaw. C accumulation rates in lowland thermokarst chronosequences suggest a mixed sink/source effect, with post-thaw increases in surface accumulation potentially offset by decomposition at depth, or enhanced initial decomposition of C from previously frozen soils, followed by long-term net uptake of post-thaw peat. Large uncertainties remain regarding the turnover of soil organic C in boreal soil, yet enhanced decomposition has likely offset the increase in NPP, resulting in a reduced sink activity relative to pre1960s.

Harden, J. W.; O'Donnell, J.; Fuller, C.; Sierra, C. A.; Johnson, K. D.; Manies, K.; Jorgenson, T.; Jones, M.; Ewing, S. A.; Yue, C.; Turetsky, M.

2013-12-01

305

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

NASA Astrophysics Data System (ADS)

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.

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

2013-11-01

306

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

NASA Technical Reports Server (NTRS)

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.

Pelletier-Travis, Ramona E.

1991-01-01

307

Chemical Changes in Agricultural Soils of Korea: Data Review and Suggested Countermeasures  

Microsoft Academic Search

The monitoring of chemical properties, including heavy metals, in soils is necessary if better management and remediation practices are to be established for polluted soils. The National Institute of Agricultural Science and Technology initiated a monitoring study that investigated fertility and heavy metal contents of the benchmarked soils. The study covered paddy soils, upland soils, and horticultural soils in the

I. S. Jo; M. H. Koh

2004-01-01

308

Properties and Classification of the Tepui Peats  

Microsoft Academic Search

\\u000a In the Guayana Highlands, peats have formed along an elevation gradient spanning roughly from 600 m to 2,800 m?a.s.l. They\\u000a have been studied earlier in the eastern highlands from a paleogeographic point of view using radiocarbon dating and pollen\\u000a analysis, but little is known about their morphological, physical, and chemical characteristics, and their taxonomic classification.\\u000a This study reports on the properties of

P. García; R. Schargel; J. A. Zinck

309

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

USGS Publications Warehouse

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.

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

1998-01-01

310

Variations in saturated and unsaturated water movement through an upland floodplain wetland, mid-Wales, UK  

NASA Astrophysics Data System (ADS)

SummaryVariations in inferred water movement are examined during a two-year study of an upland floodplain wetland at Afon Llwyd, in mid-Wales, UK in 2001 and 2002. Soil-water pressures ( ?) were monitored by six tensiometer nests, each comprising two sensors at depths of 30 and 60 cm below the surface. Detailed sedimentary sections were produced and changes in saturated and unsaturated hydraulic conductivity (and their relationship to ?) were estimated. Seasonal trends in ? were identified and vertical hydraulic gradients within different tensiometer nests were derived and interpreted in the context of the local channel and floodplain sedimentology, channel bedform morphology and hydro-climatic conditions. Although there is considerable variation in ?, the results display characteristic trends at several levels: (1) in relationship to precipitation; (2) reflecting changes in river stage (with downstream stage providing base-level control through a riffle-pool couplet); and (3) marked spatial variations in the direction and rate of water movement. These controls influence water redistribution through the wetland, which reflects the relative position of distinct sedimentary units within the floodplain. The results demonstrate that water movement is episodic and characterised by relatively rapid horizontal water fluxes during and immediately following individual rain events, followed by residual seepage to the river and water movement under a local soil moisture gradient. The implications of these results include elucidating the role of upland floodplains in buffering sub-surface drainage, and attenuating patterns of river flow under base flow conditions. This has the potential to advance the basis for future upland floodplain wetland and channel restoration schemes.

Bradley, Chris; Clay, Andrew; Clifford, Nicholas J.; Gerrard, John; Gurnell, Angela M.

2010-11-01

311

OPEN GROUND IN UPLAND FORESTS: A REVIEW OF ITS  

E-print Network

OPEN GROUND IN UPLAND FORESTS: A REVIEW OF ITS POTENTIAL AS WILDLIFE HABITAT AND APPROPRIATE. The requirements of various species and groups of plants and animals known to use forest open ground are reviewed

312

The geology, botany and chemistry of selected peat-forming environments from temperate and tropical latitudes  

USGS Publications Warehouse

Peat has been studied in several geologic settings: (1) glaciated terrain in cold temperate Maine and Minnesota, U.S.A.; (2) an island in the Atlantic Ocean off the coast of Maine, where sea level is rising; (3) the warm temperate U.S. Atlantic and Gulf Coastal Plains, where sea level has changed often; and (4) the tropical coast of Sarawak, Malaysia, and the tropical delta of the Batang Hari River, Sumatra, Indonesia. Most of these deposits are domed (ombrotrophic or partly ombrotrophic) bogs in which peat accumulation continued above the surface of the surrounding soil. However, the bogs of the U.S. Atlantic and Gulf Coastal Plains are comparatively not as domed, and many have almost level surfaces. In some bogs, aquatic or semi-aquatic plant materials accumulated, replaced water in the depressions, and formed a surface on which marsh or swamp vegetation could subsequently live, die, and accumulate. In others, the plant materials accumulated initially on level silt or sand surfaces supporting marshes or swamps. As the peat dome formed, plants growing on it changed from luxuriant ones near the base of the dome, where nutrients were brought into the bog by surface and ground water, to stunted ones at the top of the dome, where the raised bogs are fed by nutrient-poor precipitation. The physical and chemical changes that take place in the sequence of environments from the pond stage of deposit development, through the grassy marsh stage, through the forested swamp stage, and finally through the heath dome stage can be measured in terms of acidity and ash, volatile matter, carbon, hydrogen, nitrogen, sulfur and oxygen contents, as well as in the kind and distribution of trace elements. The organic and inorganic contents of the deposits relate to geomorphology, and geomorphology relates to their settings. As models of coal formation, some domed peat deposits may help in solving problems of distribution and character of ancient coal beds. But clearly not all peat deposits are precursors of coal. Most Holocene peat deposits are subject to destruction by erosion, fire and decomposition through microbial and chemical oxidation before burial. The best environments for coal precursors have biomass accumulation, a continuously rising water table within the mass, and minimum influx of clay and silt until preservation by burial. The most suitable settings for future economic coal deposits are domed bogs that accumulate thick, widespread peat having low ash and low sulfur contents. The ombrotrophic peat deposits of tropical Sarawak and Sumatra are thick and extensive, contain low-ash and low-sulfur peat, and have high heating values. They are considered to be the best tropical coal analogs because of their extent and chances of preservation; the base of the peat is below adjacent river levels, and chemical and structural conditions are favorable for accumulation. ?? 1989.

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

1989-01-01

313

Responses of Isolated Wetland Herpetofauna to Upland Forest Management  

SciTech Connect

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.

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

2002-01-02

314

Acaulospora brasiliensis comb. nov. and Acaulospora alpina ( Glomeromycota ) from upland Scotland: morphology, molecular phylogeny and DNA-based detection in roots  

Microsoft Academic Search

Spores of two supposedly arbuscular mycorrhizal fungal species, new to the United Kingdom and recently described as Acaulospora alpina and Ambispora brasiliensis (Glomeromycota), were discovered in soil samples from moorland in upland Scotland. Soil and plant trap pot cultures were established, but\\u000a attempts to establish these fungi in single-species pot cultures with Plantago lanceolata as host were unsuccessful. Nevertheless, based

Manuela Krüger; Christopher Walker; Arthur Schüßler

2011-01-01

315

Development of an alternative artificial soil for earthworm toxicity testing in tropical countries  

Microsoft Academic Search

The standard soil invertebrate toxicity tests developed by OECD and ISO use an artificial soil as the test substrate, which contains sphagnum peat as a component. This type of peat is not widely available. Investigation of possible alternative substrates using locally available materials therefore is vital for performing such ecotoxicity tests, particularly in the tropics. We studied the suitability of

Cornelis A. M. van Gestel

2009-01-01

316

Soil–Methanogen Interactions in Two Peatlands (Bog, Fen) in Central New York State  

Microsoft Academic Search

Rates of methanogenesis vary widely in peat soils, yet the reasons are poorly known. We examined rates of methanogenesis and methanogen diversity in relation to soil chemical and biological characteristics in 2 peatlands in New York State. One was an acidic (pH < 4.5) bog dominated by Sphagnummosses and ericaceous shrubs, although deeper peat was derived from sedges. The other

Mark D. Dettling; Joseph B. Yavitt; Hinsby Cadillo-Quiroz; Christine Sun; Stephen H. Zinder

2007-01-01

317

Peat decomposition in a transitional mire in central Poland  

Microsoft Academic Search

The goal of our work was to estimate the rate of the peat formation and mineralization at two depths: 30 cm (the aerobic zone)\\u000a and 60 cm (the anaerobic zone). An experiment on peat incubation was performed for two years. In the first year, at the depth\\u000a of 30 cm, the peat lost about 14% of its mass in the

A. A. Titlyanova; S. V. Shibareva; P. Bienkowski

2011-01-01

318

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

USGS Publications Warehouse

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.

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

1987-01-01

319

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

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

320

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

E-print Network

in a subtropical wetland: Water Conservation Area-2A, the Florida Everglades, U.S. Soil series were collected wetlands have shown high variability due to their complex composition of water, soil, floc in upland systems Jongsung Kim Sabine Grunwald* Univ. of Florida Soil and Water Science Dep. 2169 Mc

Grunwald, Sabine

321

The adsorption of basic dyes from aqueous solution on modified peat–resin particle  

Microsoft Academic Search

Modified peat was prepared by mixing thoroughly raw peat with sulfuric acid, and modified peat–resin particle was obtained, by mixing modified peat with solutions of polyvinylalcohol (PVA) and formaldehyde. In this paper, the adsorption of Basic Magenta and Basic Brilliant Green onto modified peat–resin particle is examined. The adsorption isotherm showed that the adsorption of basic dyes on modified peat–resin

Qingye Sun; Linzhang Yang

2003-01-01

322

Spatial Distribution of Soil Nutrients in a Northern Everglades Marsh: Water Conservation Area 2A  

E-print Network

Spatial Distribution of Soil Nutrients in a Northern Everglades Marsh: Water Conservation Area 2A W of P, N, C, and related physico-chemical parameters in the peat soils (Histosols) of Water Conservation

Florida, University of

323

Acidophilic Methanotrophic Communities from Sphagnum Peat Bogs  

PubMed Central

Highly enriched methanotrophic communities (>25 serial transfers) were obtained from acidic ombrotrophic peat bogs from four boreal forest sites. The enrichment strategy involved using media conditions that were associated with the highest rates of methane uptake by the original peat samples, namely, the use of diluted mineral medium of low buffering capacity, moderate incubation temperature (20°C), and pH values of 3 to 6. Enriched communities contained a mixture of rod-shaped bacteria arranged in aggregates with a minor contribution of Hyphomicrobium-like cells. The growth stoichiometry of isolates was characteristic of methanotrophic bacteria (CH4/O2/CO2=1:1.1:0.59), with an average apparent yield of 0.41 ± 0.03 g of biomass C/g of CH4-C. DNA from each enrichment yielded a PCR product of the expected size with primers for both mmoX and mmoY genes of soluble methane monooxygenase. Two types of sequences were obtained for PCR-amplified fragments of mmoX. One of them exhibited high identity to the mmoX protein of the Methylocystis-Methylosinus group, whereas the other showed an equal level of divergence from both the Methylosinus-Methylocystis group and Methylococcus capsulatus (Bath) and formed a distinct branch. The pH optimum for growth and for CH4 uptake was 4.5 to 5.5, which is very similar to that for the optimum CH4 uptake observed in the original peat samples. These methanotrophs are moderate acidophiles rather than acidotolerant organisms, since their growth rate and methane uptake were much lower at neutral pH. The growth of the methanotrophic community was enhanced by using media with a very low salt content (20 to 200 mg/liter), more typical of their natural environment. All four enriched communities grew on N-free medium. PMID:9501432

Dedysh, Svetlana N.; Panikov, Nicolai S.; Tiedje, James M.

1998-01-01

324

Plant Species Anaerobiosis and DOC Dynamics in a Peat-Forming Wetland, New York State  

NASA Astrophysics Data System (ADS)

We quantified spatial and temporal patterns of dissolved organic carbon (DOC) concentrations in the shallow peat soil of a freshwater wetland (located in central New York State) and correlated the patterns with anaerobiosis in roots of the dominant plant species. Sampling was stratified in zones dominated by: lakebank sedge (Carex lacustris), common cattail (Typha latifolia), purple loosestrife (Lythrum salicaria) or soft rush (Juncus effusus). Concentrations of DOC peaked in late summer and were much greater in wet years (14.3 mg C/L) than during summer drought (5.3 mg C/L). DOC concentrations did not vary significantly as a function of plant species and were greater in subsurface peat (13.3 mg C/L at 20 cm depth) than in surface peat (8.6 mg C/L at 5 cm depth). Anaerobiosis was pronounced in cattail in the spring and autumn, in purple loosestrife in mid summer, but showed little seasonal pattern in rush and in sedge. Although recent ecological research has shown that plant species can control belowground processes, we found little evidence for plant species control of DOC dynamics in this wetland.

Yavitt, J. B.; Williams, C. J.

2004-05-01

325

Retention Time Effect on Metal Removal by Peat Columns (U).  

National Technical Information Service (NTIS)

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 ...

E. A. Nelson

2007-01-01

326

Biochar as a growing media additive and peat substitute  

NASA Astrophysics Data System (ADS)

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.

Steiner, C.; Harttung, T.

2014-09-01

327

Peat Resources of North Carolina. Quarterly Progress Report.  

National Technical Information Service (NTIS)

Although the work on North Carolina peat deposits is far from complete, a preliminary estimate of the amount of peat was made. Table 1 has the listing of all three types of deposits, Pocosin, River Flood Plain and Carolina Bays, and their description such...

R. L. Ingram, L. J. Otte

1980-01-01

328

Peat: A Natural Source for Dermatocosmetics and Dermatotherapeutics  

PubMed Central

In recent years the interest for natural substances in dermatotherapy and cosmetics has increased. Peat is a complex natural source of humic substances that are of potential interest in both dermatology and cosmetology. Humic substances in peat have been partially characterized and pharmacologic and biologic activities have been documented. Possible clinical applications are outlined. PMID:20300366

Wollina, Uwe

2009-01-01

329

Restoring peat-accumulating function on cutaway peatlands  

Microsoft Academic Search

Summary In order to focus restoration efforts towards specific vegetation groups in fen restoration, knowledge of the peat-accumulating potential of dominant fen species is critical. Historical information (macrofossil analyses) was examined and summarised to characterise fen peat of North American boreal peatlands. Cyperaceae and Sphagnum species were found to be important vegetation groups for accumulating organic matter. Addition - ally,

Martha Graf; Line Rochefort

330

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

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

331

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

NASA Astrophysics Data System (ADS)

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.

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

2009-12-01

332

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...

333

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

NASA Astrophysics Data System (ADS)

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

Kozan, O.

2011-12-01

334

Topsoil Removal in a Restored Peat Wetland: an Experimental Study  

NASA Astrophysics Data System (ADS)

Topsoil removal is a common practice in wetland restoration projects for eliminating the weed seed bank, any persistent herbicides or pesticides, as well as lowering the soil surface closer to the water table. In 2000, a peat wetland that was drained 85 years ago for agriculture was restored by removing 40-50 cm of topsoil, seeding wetland plants, and reestablishing wetland hydrology. In 2004, six 100m2 scraped plots and six adjacent 100m2 unscraped control plots were sampled in North and South fields. Plant percent cover and aboveground biomass was measured in each plot. Depth to the water table was greater in the North field because this field had a higher elevation than the South field, which was partially submerged. Total biomass was greater in the North field than in the South. In the North field, species diversity and richness were higher in treatment plots than control plots, but there was no difference in the South field. Dominant species were different between the control and treatment plots and between North and South fields. These results indicate that both water levels and topsoil removal have dramatic impacts on plant community establishment in restored wetlands.

Hausman, C. E.; Fraser, L.; de Szalay, F. A.

2005-05-01

335

Partitioning of ecosystem respiration in a paludified shallow-peat spruce forest in the southern taiga of European Russia  

NASA Astrophysics Data System (ADS)

Soil, tree stems, and ecosystem carbon dioxide fluxes were measured by chambers and eddy covariance methods in a paludified shallow-peat spruce forest in the southern taiga of European Russia (Tver region, 56° N 33° E) during the 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 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 the total ecosystem respiration (ER) in this paludified shallow-peat spruce forest. On average, 49% of the ER came from soil respiration. We found that the soil fluxes exhibited high seasonal variability, ranging from 0.7 to 10 ?mol m-2 s-1. Generally, the soil respiration depended on the soil temperature and ground water level. In drought conditions, the soil respiration was low and did not depend on temperature. The 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. The tree stem respiration in midsummer was about 3-5 ?mol m-2 s-1 for dominant trees and about 1-2 ?mol m-2 s-1 for subdominant trees. The respiration of living tree stems was about 10-20% of the ER.

Kurbatova, J.; Tatarinov, F.; Molchanov, A.; Varlagin, A.; Avilov, V.; Kozlov, D.; Ivanov, D.; Valentini, R.

2013-12-01

336

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

NASA Astrophysics Data System (ADS)

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.

Kurbatova, Juliya

2014-05-01

337

Decomposition of rice residue in tropical soils  

Microsoft Academic Search

The decomposition processes of intact rice residue (leaf blades) in Maahas soil of the Philippines were investigated by incubation experiments at 30°C. The experiments dealt with nitrogen immobilization by rice residue under lowland and upland conditions. Rice residue which is low in nitrogen. absorbed nitrogen from the soil and from the added fertilizer (ammonium sulfate) during its decomposition under both

Tadakatsu Yoneyama; Tomio Yoshida

1977-01-01

338

Development and status of the IGT PEATGAS Process for production of synthetic fuels from peat  

Microsoft Academic Search

US peat resources are the third largest in the world and are estimated to be about 1440 quads, equivalent to 240 billion barrels of crude oil. In the contiguous 48 states, peat deposits are generally located in areas with no other significant fossil fuel resources. Therefore, for those areas, peat represents an important source of energy. Peat conversion research at

D. V. Punwani; A. M. Rader; M. J. Kopstein

1979-01-01

339

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

NASA Astrophysics Data System (ADS)

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.

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

340

Destabilization of subarctic peat plateau-thermokarst lake complexes under warmer conditions  

NASA Astrophysics Data System (ADS)

Introduction Large quantities of soil organic carbon are stored in northern peatlands located in the southern continuous and discontinuous permafrost zones, where permafrost degradation can be expected to occur as a result of changes in climatic conditions (e.g. Tarnocai, 2006). In this region, peat plateaus dotted with thermokarst lakes and fens are common landscape features. Permafrost thawing caused by warming or increased precipitation can result in increased thermokarst lake formation, lateral expansion and/or drainage. A better understanding, and quantification, of spatio-temporal variations in these landforms in relation to climate change is important for predicting the future thawing permafrost carbon feedback. Aim, study area and methods The objective of this study has been to quantify dynamics in thermokarst lake extent in subarctic peat plateaus located along a climate/permafrost gradient during the last ~35-50 years (Sannel and Kuhry, in press). At three study sites; Hudson Bay Lowlands in west-central Canada, Rogovaya in east-European Russia and Tavvavuoma in northern Sweden, remote sensing time-series analysis of historical panchromatic aerial photographs and QuickBird/IKONOS scenes has been performed. For the land-water separation manual delineation in combination with binary encoding of transects perpendicular to the shoreline was used, as this method was identified to be most accurate for high spatial resolution mapping of thermokarst lakes (Sannel and Brown, 2010). Results and conclusions From the mid 1970s until the mid 2000s there has been an increase in mean annual air temperature (MAAT), winter precipitation and ground temperature in all three study areas. The two peat plateaus located in the southern continuous and the discontinuous permafrost zones, where MAATs are below -5°C and ground temperatures are -2°C or colder, have experienced small changes in thermokarst lake extent (<0.4% per decade). In the peat plateau located in the sporadic permafrost zone where the MAAT is around -3°C, and the ground temperature is close to 0°C, extensive lake drainage (~8% per decade) and infilling with fen vegetation has taken place and at the same time many new thermokarst lakes have formed. Our results suggest that warmer MAAT, and subsequent warmer ground temperatures, can cause rapid destabilization of peat plateau-thermokarst lake complexes, and that the critical threshold in MAAT is between -3°C and -5°C. In a future warmer climate, permafrost degradation can cause significant impacts on landscape patterns, hydrology and carbon exchange also in areas with extensive peat plateaus which at present experience stable permafrost conditions. References Sannel, A.B.K. and Brown, I.A. 2010. High resolution remote sensing identification of thermokarst lake dynamics in a subarctic peat plateau complex. Canadian Journal of Remote Sensing 36, S26-S40. Sannel, A.B.K. and Kuhry, P. in press. Warming-induced destabilization of peat plateau/thermokarst lake complexes. Journal of Geophysical Research - Biogeosciences. Tarnocai, C. 2006. The effect of climate change on carbon in Canadian peatlands. Global and Planetary Change 53, 222-232.

Sannel, B. A.; Kuhry, P.

2011-12-01

341

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

NASA Astrophysics Data System (ADS)

Nitrogen belongs to chemical elements whose biogeochemical cycles are most heavily disturbed by human activities, and large regions worlwide experience elevated depositions of reactive N (NO3-, NH4+). Peatlands contain as much as 15 % of the world's soil N. It it is unclear whether fertilizing by anthopogenic N will lead to higher storage of C in wetlands. Elevated N input may lead to both higher net primary productivity, but will also augment microbial decomposition. Here we discuss two aspects of N cycling in Sphagnum-dominated bogs in the Czech Republic, an area characterized by a steep north-south pollution gradient and high annual N deposition (60 kg ha-1). These two aspects are N inventory in 210Pb-dated peat cores, and post-depositional mobility of N in peat. We compared the N inventory in two Czech bogs, differing in pollution, with cumulative atmospheric N input. We hypothesized that the total amount of N in the peat cores would be smaller than the cumulative N input (leaching of excess N from the bog, denitrification). The two bogs were VJ (industrial north) and CB (rural south). The investigated period was 1885-2002. The total amount of N was 4020 kg ha-1 at VJ and 1530 kg ha-1 at CB. Peat in the north contained 2.6 times more N than in the south. Historical rates of N deposition in the Czech Republic are well known (numerous papers by Kopacek). To estimate cumulative N inputs into the bogs, we also used the monthly N depositions between 1994 and 2002, measured in two nearby catchments. The estimated cumulative atmospheric N input was 1350 kg ha-1 at VJ, and 530 kg ha-1 at CB. In both cases, the amount of N found in peat was 3 times higher than the estimated atmospheric N input. Such high storage of N in peat is surprising. Post-depositional mobility of N may help to explain the discrepancies between atmospheric N inputs and N storage in peat. We found two-fold evidence for post-depositional mobility of N. Maximum N concentrations at VJ were observed in layers dated at 1950, whereas pollution level increased up to 1980, and dropped thereafter. At the end of an 18-month reciprocal peat transplant experiment between VJ and CB, we found that N isotope ratios N converged to the host site. The magnitude of the isotope change was 3 per mil, the affected depth was 10 cm. Our results are consistent with the concept of Lamers et al. (2000) in that both ^15N and the found shift in N peaks downcore confirmed removal of N from surface moss under high N depositions. On the other hand, the excess of stored N relative to the cumulative N input remains unexplained, and merits further study.

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

2013-04-01

342

Single-stage fluidized-bed gasification. [Peat  

SciTech Connect

The single-stage fluidized-bed gasification process, in addition to being a simple system, maximizes gas production and allows the economic exploitation of small peat deposits. The objective of this gasification project is to conduct experiments in order to obtain data for designing a single-stage fluidized-bed gasifier, and to evaluate the economics of converting peat to synthesis gas and to SNG by this process. An existing high-temperature and high-pressure process development unit (PDU) was modified to permit the direct feeding of peat to the fluidized bed. Peat flows by gravity from the feed hopper through a 6-inch line to the screw-feeder conveyor. From there, it is fed to the bottom tee section of the reactor and transported into the gasification zone. Oxygen and steam are fed through a distributing ring into the reactor. Gasification reactions occur in the annulus formed by the reactor tube and a central standpipe. Peat ash is discharged from the reactor by overflowing into the standpipe and is collected in a solids receiver. All process steams are measured and sampled for data analysis. A total of 24 tests have been conducted in this unit; detailed results of all tests have been published. Peats from Minnesota, Maine, and North Carolina were tested. Tables 1 and 2 summarize the operating ranges used and the product yields achieved in these tests. A wide range of operating conditions was tested. The following discussion of results is directed toward the Minnesota peat tests. Several conclusions can be drawn: high peat conversions (> 90%) can be achieved under relatively mild conditions. Pressure has no apparent effect on conversion. Low oil yields, less than 1% of the feed carbon, were obtained as expected with the bottom feed configuration. External steam feed was not required to achieve high carbon conversions. Apparently, sufficient reaction steam is produced during peat devolatilization.

Lau, F.S.; Rue, D.M.; Weil, S.A.; Punwani, D.V.

1982-04-01

343

Peat pyrolysis and the analytical semi-empirical model  

SciTech Connect

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.

Feng, J.; Green, A.E.S. [University of Florida, Gainesville, FL (United States). Clean Combustion Technology Laboratory

2007-07-01

344

Physicochemical properties of carbon nanotubes obtained from peat moss  

NASA Astrophysics Data System (ADS)

It has been established that mechanochemical treatment of amorphous carbon synthesized by pyrolysis from brown peat moss leads to the formation of carbon nanotubes. Complex studies of the sorptive properties of pyrolytic amorphous carbon and multiwalled nanotubes obtained from peat moss have been made. It has been shown that the ability of carbon nanotubes for acidic modification depends on the technological parameters of their formation, and the efficiency of the sorptive capacity volume of such nanotubes depends on their storage time. The possibility of using carbon materials from peat moss as effective enterosorbents has been considered.

Onishchenko, D. V.; Reva, V. P.

2013-03-01

345

Strong Binding Environments for Mercury in Peat  

NASA Astrophysics Data System (ADS)

Mercury toxicity to humans and wildlife largely originates in bacterial generation of methylmercury in the aquatic environment. Methylmercury may be inhibited from forming if mercury(II) is bound to reduced sulfur in dissolved or solid natural organic matter. Mercury(II)-reduced sulfur bonds are the strongest type of binding between mercury and natural organic matter, but the molecular configurations and binding strengths have still not been fully characterized despite many recent investigations using synchrotron-based analytical capabilities and competitive ligand experimentation. Also, at the low but toxic concentration levels of mercury(II) in the environment, characterization with these approaches is difficult. Using Extended X-ray Absorption Fine Structure spectroscopy at liquid He temperature we have obtained new information on the binding environment of mercury(II) adsorbed to peat obtained from the Florida Everglades at five mercury concentrations ranging from 60 to 99,000 ppm. These data were complemented with X-ray Absorption Near Edge Structure spectroscopy for the speciation of reduced sulfur. At mercury(II) concentrations of 60 and 350 ppm the dominant binding occurred in structures similar to those observed for some metallothioneins. At concentrations of 4000 ppm, mercury(II) occurred mainly in a linear arrangement bonded to two sulfurs. At higher concentrations, mercury(II) was bound to two oxygens in a five-membered chelate ring structure. The new binding configuration observed at 60 and 350 ppm is likely more stable than any reported previously, suggesting that peat may be a good material to apply in remediating environments contaminated with mercury.

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

2008-12-01

346

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

NASA Astrophysics Data System (ADS)

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).

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

2014-05-01

347

Integrating parsimonious models of hydrological connectivity and soil biogeochemistry to simulate stream DOC dynamics  

NASA Astrophysics Data System (ADS)

improve understanding and prediction of dissolved organic carbon (DOC) sources and fluxes in northern peat-dominated catchments, we present the development and application of a parsimonious tracer-aided rainfall-runoff model coupled with a biogeochemistry subroutine able to concurrently simulate streamflow and DOC dynamics. The modeling approach which included quantitative assessment of associated uncertainties was conditioned by geochemical tracers which discriminate dominant water sources. Integration of DOC was predicated on statistical time series models which identified air temperature and streamflow as the key proxies that capture DOC supply and transport processes in two upland catchments in Scotland, UK. Conceptualizing the nonlinear partitioning of quick near-surface and slower groundwater runoff sources in combination with a DOC mass balance resulted in a coupled, low-parameter mechanistic model. Model tests showed mostly sensitive parameters and reasonable simulation results with seasonally controlled DOC supply and event-based DOC transport. Transport is facilitated even for smaller events by overland flow from saturated histosols connected to the stream network. However, during prolonged dry periods, near-surface runoff "switches off" and stream DOC is dominated by low concentration groundwaters. Furthermore, the model was able to explain subtle differences in DOC dynamics between the two catchments mainly reflecting the distribution of saturated soils and available storage. We conclude that tracers and statistical time series models can successfully guide the development of parsimonious yet structurally consistent water quality models. Parsimonious models provide tools for estimating DOC dynamics and loads with reduced uncertainty and potentially greater transferability.

Birkel, Christian; Soulsby, Chris; Tetzlaff, Doerthe

2014-05-01

348

Organic carbon export from upland and forested wetland watersheds  

Microsoft Academic Search

Export of organic carbon per unit runoff from five small, eastern North Carolina watersheds with considerable swamp drainage was severalfold higher than the export rates from upland watersheds reported in the literature. This reflects the higher concentrations of organic carbon, especially dissolved forms, in swamp waters and is probably attributable to increased contact time between water and organic debris as

PATRICK J. MULHOLLAND; EDWARD J. KUENZLER

1979-01-01

349

Chloroplast Genome Variation in Upland and Lowland Switchgrass  

PubMed Central

Switchgrass (Panicum virgatum L.) exists at multiple ploidies and two phenotypically distinct ecotypes. To facilitate interploidal comparisons and to understand the extent of sequence variation within existing breeding pools, two complete switchgrass chloroplast genomes were sequenced from individuals representative of the upland and lowland ecotypes. The results demonstrated a very high degree of conservation in gene content and order with other sequenced plastid genomes. The lowland ecotype reference sequence (Kanlow Lin1) was 139,677 base pairs while the upland sequence (Summer Lin2) was 139,619 base pairs. Alignments between the lowland reference sequence and short-read sequence data from existing sequence datasets identified as either upland or lowland confirmed known polymorphisms and indicated the presence of other differences. Insertions and deletions principally occurred near stretches of homopolymer simple sequence repeats in intergenic regions while most Single Nucleotide Polymorphisms (SNPs) occurred in intergenic regions and introns within the single copy portions of the genome. The polymorphism rate between upland and lowland switchgrass ecotypes was found to be similar to rates reported between chloroplast genomes of indica and japonica subspecies of rice which were believed to have diverged 0.2–0.4 million years ago. PMID:21887356

Young, Hugh A.; Lanzatella, Christina L.; Sarath, Gautam; Tobias, Christian M.

2011-01-01

350

Bird populations in upland spruce plantations in northern Britain  

Microsoft Academic Search

The aim of this study was to measure bird numbers and species richness in upland spruce forests in relation to forest habitat variables, as a basis for a computer model to predict how bird populations were likely to change under different forest management regimes.In each of the two study areas, at Cowal, Argyll and Kielder, Northumberland, 88 study plots were

I. J. Patterson; J. G. Ollason; P. Doyle

1995-01-01

351

Historical land use evolution in a tropical acid upland agroecosystem  

Microsoft Academic Search

Understanding the historical evolution of land use in humid tropical agroecosystems may assist in developing more appropriate farming systems better able to sustain dense human populations, alleviate deforestation and regenerate degraded land resources. We analyzed land use change over a 40 year period for a key acid upland farming systems research site (8 km × 10 km) undergoing rapid transformation

Dennis P. Garrity; Patricio C. Agustin

1995-01-01

352

Isotopic Characterization of Lead in the Scottish Upland Environment  

Microsoft Academic Search

Experimental plots have been set up at two Research Stations in upland areas of Scotland with the intention of characterising environmental samples using lead isotopic composition which varies according to the original source of the lead. Thermal ionisation mass spectrometry (TIMS) was used to measure lead isotope ratios with high precision. The Pb\\/Pb ratios in rainwater were in the range

J. R. Bacon; M. L. Berrow; C. A. Shand

1995-01-01

353

Prescribed burning effects on upland Quercus forest structure and function  

Microsoft Academic Search

The effects of prescribed burning, herbicide application, and thinning treatments were examined in upland Quercus stands with a replicate block field study. Two site types were analyzed: (1) nonsuccessional with a Quercus overstory and Quercus understory, and (2) successional with a Quercus overstory and an Acer saccharum understory. Treatments were examined for their effects on vegetation structure and composition, especially

Scott B. Franklin; Philip A. Robertson; James S. Fralish

2003-01-01

354

Nitrogen Components in Coal Peat and Petroleum. Literature Study.  

National Technical Information Service (NTIS)

Nitrogen compounds in living organic tissues mainly appear in proteins. Protein derived amino acids can still be identified in peat. Besides also amino acids from bacteriological activities (fixation of nitrogen from the air) are found. Nitrogen content o...

M. Bengtsson

1988-01-01

355

Some fundamental aspects of the dewatering of peat.  

National Technical Information Service (NTIS)

The purpose of this work has been to study possible dewatering systems and methods which allows a fuel peat production independent of climate and weather conditions with a special emphasise on the influence of the mechanical dewatering operation. The dry ...

M. Muenter

1991-01-01

356

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

SciTech Connect

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.

Armentano, T. V.

1982-01-01

357

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

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.

Jafarov, Elchin E.; Romanovsky, Vladimir E.; Genet, Helene; McGuire, Anthony D.; Marchenko, Sergey S.

2013-01-01

358

0038-075X/06/17102-152-166 Soil Science  

E-print Network

" with the zonal soils of the region. The typical upland soils in this part of the Pictured Rocks National0038-075X/06/17102-152-166 Soil Science Copyright 0 2006 by Lippincott Williams & Wilkins, Inc. AN APPLICATION OF THE RUNGE "ENERGY MODEL" OF SOIL DEVELOPMENT IN MICHIGAN'S UPPER PENINSULA Randall J. Schaetzl1

Schaetzl, Randall

359

Secondary Mineral Genesis from Chlorite and Serpentine in an Ultramafic Soil Toposequence  

Microsoft Academic Search

synthesis of smectite in poorly drained soils. For exam- ple, Istok and Harward (1982) found smectite, chlorite, The origin of secondary phyllosilicates in serpentinitic soils of dif- and serpentine within poorly drained soils, but found fering moisture regimes is incompletely understood. The objective of only serpentine and chlorite in well-drained upland soils. this study was to determine the genesis of

B. D. Lee; S. K. Sears; R. C. Graham; C. Amrhein; H. Vali

2003-01-01

360

Soil texture and nitrogen mineralization potential across a riparian toposequence in a semi-arid savanna  

Microsoft Academic Search

Soil texture is an important influence on nutrient cycling in upland soils, with documented relationships between mineral particle size distribution and organic matter retention, nitrogen (N) mineralization, microbial biomass and other soil properties. However, little is known of the role of mineral particle size in riparian soils, where fluvial sorting creates strong spatial contrasts in the size distribution of sediments

J. Scott Bechtold; Robert J. Naiman

2006-01-01

361

Effect of peat on physicomechanical properties of cemented brick.  

PubMed

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

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

2014-01-01

362

Atmospheric nitrogen deposition promotes carbon loss from peat bogs.  

PubMed

Peat bogs have historically represented exceptional carbon (C) sinks because of their extremely low decomposition rates and consequent accumulation of plant remnants as peat. Among the factors favoring that peat accumulation, a major role is played by the chemical quality of plant litter itself, which is poor in nutrients and characterized by polyphenols with a strong inhibitory effect on microbial breakdown. Because bogs receive their nutrient supply solely from atmospheric deposition, the global increase of atmospheric nitrogen (N) inputs as a consequence of human activities could potentially alter the litter chemistry with important, but still unknown, effects on their C balance. Here we present data showing the decomposition rates of recently formed litter peat samples collected in nine European countries under a natural gradient of atmospheric N deposition from approximately 0.2 to 2 g.m(-2).yr(-1). We found that enhanced decomposition rates for material accumulated under higher atmospheric N supplies resulted in higher carbon dioxide (CO2) emissions and dissolved organic carbon release. The increased N availability favored microbial decomposition (i) by removing N constraints on microbial metabolism and (ii) through a chemical amelioration of litter peat quality with a positive feedback on microbial enzymatic activity. Although some uncertainty remains about whether decay-resistant Sphagnum will continue to dominate litter peat, our data indicate that, even without such changes, increased N deposition poses a serious risk to our valuable peatland C sinks. PMID:17151199

Bragazza, Luca; Freeman, Chris; Jones, Timothy; Rydin, Håkan; Limpens, Juul; Fenner, Nathalie; Ellis, Tim; Gerdol, Renato; Hájek, Michal; Hájek, Tomás; Iacumin, Paola; Kutnar, Lado; Tahvanainen, Teemu; Toberman, Hannah

2006-12-19

363

Evaluation of the VIIRS Land Algorithms at Land PEATE  

NASA Technical Reports Server (NTRS)

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

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

2010-01-01

364

Soil organic carbon stocks in soil aggregates under different land use systems in Nepal  

Microsoft Academic Search

We investigated the soil organic carbon (SOC) associated with various aggregate size fractions in soil profiles under different land uses. Bulk soil samples were collected from incremental soil depths (0–10, 10–20, 20–40, 40–60, 60–80 and 80–100 cm) from sites with the four dominant land use types [forest, grazing land, irrigated rice in level terraces (Khet) and upland maize-millet in sloping

B. M. Shrestha; B. K. Sitaula; B. R. Singh; R. M. Bajracharya

2004-01-01

365

SOIL COLLOIDS AS A FACTOR IN THE UPTAKE OF COBALT, CESIUM, AND STRONTIUM BY PLANTS  

Microsoft Academic Search

A study of the uptake of Co, Cs, and Sr by rye. garden peas, and ; soybeans showed that the amount of these elements harvested, as well as the ; concentration in the plants, varied with the nature of the soil colloid on which ; they were grown. Illite, kaolinite, montmorillonite, peat (fibrous), peat ; (sedimentary), and Putnam clay were

E. R. Graham; D. D. Killion

1962-01-01

366

Hydrology and seasonality determine distinct DOC export mechanisms in contrasting upland catchments in Scotland  

NASA Astrophysics Data System (ADS)

How climate variability influences soil processes, production and export of DOC are important in understanding hydrologically mediated carbon losses from soils and its affect on stream and river water quality. This necessitates understanding both biogeochemical and hydrological factors that control the quantity and timing of carbon availability for export from soils to the drainage network. Long-term records of DOC concentrations at upland catchments with contrasting climatic characteristics in Scotland were investigated for intra-annual relationships to evaluate potential long-term seasonal as well as inter-annual patterns. Catchments in West-Central Scotland (>2000 mm/yr rainfall) with high rainfall-runoff ratios, short transit times and well-connected responsive soils show a distinct annual periodicity in DOC concentrations throughout the long-term datasets. Increased DOC concentrations occurred between June and November with correspondingly lower DOC concentrations from December to May. This appears unrelated to discharge, and is dependent mainly on higher temperatures driving biological activity, increasing decomposition of available organic matter for rapid export. Relatively drier catchments (ca. 1000 mm/yr) have lower rainfall-runoff ratios, longer transit times and annual drying-wetting regimes linked to changing connectivity of soils. These are characterised by seasonal DOC concentration-discharge relationships with an autumnal flush of DOC. Temperature influences the availability of organic matter for eventual DOC transport producing a high DOC concentration-discharge relationship in summer/autumn and low DOC concentration-discharge relationship in winter/spring. These two distinct modes of seasonal DOC transport have important implications for understanding changes in DOC concentrations and export brought about by climate changes (temperature, rainfall and deposition patterns) and modeling of aquatic carbon losses from soil-types under different hydrological regimes.

Dawson, J. J. C.; Soulsby, C.; Tetzlaff, D.; Hrachowitz, M.; Dunn, S. M.; Malcolm, I. A.

2009-04-01

367

Intensive flux measurements and analysis of greenhouse gases from an upland cabbage field at Kunsan, Korea  

NASA Astrophysics Data System (ADS)

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.

Kim, D.; Na, U.

2010-12-01

368

Influence of acetamiprid on soil enzymatic activities and respiration  

Microsoft Academic Search

The effect of a new pesticide, acetamiprid, applied at normal field concentration (0.5 mg kg?1 dried soil) and at high concentration (5 and 50 mg kg?1 dried soil), on soil enzyme activities and soil respiration in upland soil was studied. The results showed that acetamiprid had a strong negative influence on soil respiration and phosphatase activity, and the enzyme activities in soil treated with

Xiao-hua Yao; Hang Min; Zhen-hua Lü; Hai-ping Yuan

2006-01-01

369

Sulfur in the Changuinola peat deposit, Panama, as an indicator of the environments of deposition of peat and coal  

SciTech Connect

The sulfur (S) content of coal is often used to infer aspects of paleoclimate, trophic state, and proximity to marine influence, of the mire in which it was deposited. In this study, the S content of peat in a large back-barrier mire complex on the Caribbean coast of Panama is related to climatic, biological, and tectonic factors of the depositional environment. The S content is in proportion to the degree of humidification of the peat, and both are independent of the pH of the groundwater. The distribution of forms of organic and inorganic sulfur in the tropical peats are found to be comparable to published values for temperate and subtropical peats, despite differences in vegetation and climate.The distribution of high-sulfur peats in the eastern part of the deposit and low-sulfur peats in the western part, and the SE-NW transgression parallel to the trend of the coastline, reflects the regional structural trend of coseismic subsidence greatest to the southeast.

Phillips, S.; Bustin, R.M. [Univ. of British Columbia, Vancouver, British Columbia (Canada). Dept. of Geological Sciences

1996-01-01

370

Bacterial populations and environmental factors controlling cellulose degradation in an acidic Sphagnum peat.  

PubMed

Northern peatlands represent a major global carbon store harbouring approximately one-third of the global reserves of soil organic carbon. A large proportion of these peatlands consists of acidic Sphagnum-dominated ombrotrophic bogs, which are characterized by extremely low rates of plant debris decomposition. The degradation of cellulose, the major component of Sphagnum-derived litter, was monitored in long-term incubation experiments with acidic (pH 4.0) peat extracts. This process was almost undetectable at 10°C and occurred at low rates at 20°C, while it was significantly accelerated at both temperature regimes by the addition of available nitrogen. Cellulose breakdown was only partially inhibited in the presence of cycloheximide, suggesting that bacteria participated in this process. We aimed to identify these bacteria by a combination of molecular and cultivation approaches and to determine the factors that limit their activity in situ. The indigenous bacterial community in peat was dominated by Alphaproteobacteria and Acidobacteria. The addition of cellulose induced a clear shift in the community structure towards an increase in the relative abundance of the Bacteroidetes. Increasing temperature and nitrogen availability resulted in a selective development of bacteria phylogenetically related to Cytophaga hutchinsonii (94-95% 16S rRNA gene sequence similarity), which densely colonized microfibrils of cellulose. Among isolates obtained from this community only some subdivision 1 Acidobacteria were capable of degrading cellulose, albeit at a very slow rate. These Acidobacteria represent indigenous cellulolytic members of the microbial community in acidic peat and are easily out-competed by Cytophaga-like bacteria under conditions of increased nitrogen availability. Members of the phylum Firmicutes, known to be key players in cellulose degradation in neutral habitats, were not detected in the cellulolytic community enriched at low pH. PMID:21564458

Pankratov, Timofey A; Ivanova, Anastasia O; Dedysh, Svetlana N; Liesack, Werner

2011-07-01

371

Integrated monitoring of ecological conditions in wetland-upland landscapes  

USGS Publications Warehouse

Landscapes of interwoven wetlands and uplands offer a rich set of ecosystem goods and services. Managing lands to maximize ecosystem services requires information that distinguishes change caused by local actions from broader-scale shifts in climate, land use, and other forms of global change. Satellite and airborne sensors collect valuable data for this purpose, especially when the data are analyzed along with data collected from ground-based sensors. The U.S. Geological Survey (USGS) is using remote sensing technology in this way as part of the Terrestrial Wetland Global Change Research Network to assess effects of climate change interacting with land-use change and other potential stressors along environmental gradients of wetland-upland landscapes in the United States and Canada.

Gallant, Alisa; Sadinski, Walt

2012-01-01

372

Pre-coagulation for microfiltration of an upland surface water  

Microsoft Academic Search

The effect of different coagulants on cake formation and hydraulic resistance in membrane filtration of strongly coloured (SUVA?4.8) upland surface water has been studied at bench-scale under constant pressure conditions. Coagulants used were aluminium sulphate, polyaluminium chloride, ferric chloride and ferric sulphate. Optimisation of coagulation parameters was carried by conventional jar testing. The R?c (specific cake resistance in m?2) values

A. T. Pikkarainen; S. J. Judd; J. Jokela; L. Gillberg

2004-01-01

373

The role of igneous sills in shaping the Martian uplands  

NASA Technical Reports Server (NTRS)

Relations among geologic units and landforms suggest that igneous sills lie beneath much of the intercrater and intracrater terrain of the Martian uplands. The igneous rocks crop out along the upland-lowland front and in crater floors and other depressions that are low enough to intersect the sill's intrusion horizons. It is suggested that heat from the cooling sills melted some of the ice contained in overlying fragmental deposits, creating valley networks by subsurface flow of the meltwater. Terrains with undulatory, smooth surfaces and softened traces of valleys were created by more direct contact with the sills. Widespread subsidence following emplacement of the sills deformed both them and the nonvolcanic deposits that overlie them, accounting for the many structures that continue from ridged plains into the hilly uplands. Crater counts show that the deposit that became valleyed, softened, and ridged probably began to form (and to acquire interstitial ice) during or shortly after the Middle Noachian Epoch, and continued to form as late as the Early Hesperian Epoch. The upper layers of this deposit, many of the visible valleys, and the ridged plains and postulated sills all have similar Early Hesperian ages. Continued formation of valleys is indicated by their incision of fresh-appearing crater ejecta. The dependence of valley formation on internal processes implies that Mars did not necessarily have a dense early atmosphere or warm climate.

Wilhelms, D. E.; Baldwin, R. J.

1989-01-01

374

RETENTION TIME EFFECT ON METAL REMOVAL BY PEAT COLUMNS  

SciTech Connect

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.

Nelson, E

2007-02-28

375

Effects of Atmospheric Nitrate on an Upland Stream of the Northeastern USA  

NASA Astrophysics Data System (ADS)

Excess nitrogen cascades through terrestrial biogeochemical cycles and affects stream nitrate concentrations in upland forests where atmospheric deposition is an important source of anthropogenic nitrogen. We will discuss approaches including high-frequency sampling, isotopic tracers, and end-member mixing analysis that can be used to decipher the sources, transformations, and hydrological processes that affect nitrate transport through forested upland catchments to streams. We present results of studies at the Sleepers River Research Watershed in Vermont, USA, a site where we have intensively measured stream nitrate concentrations during baseflow and stormflow. Stream nitrate concentrations are typically low and nearly 75% of annual inorganic N inputs from atmospheric deposition are retained within the catchment. However, high concentrations and stream loadings of nitrate occur during storm events due to source variation and hydrological flushing of nitrate from catchment soils. Using isotopic tracers and end-member mixing analysis, we have quantified source inputs of unprocessed atmospheric nitrate and show that this stream is directly affected by nitrogen pollution. Using a long-term record of stream hydrochemistry and our findings on event- scale nitrate flushing dynamics, we then explore how stream nitrate loading may respond to anthropogenic climate forcing during the next century. Results suggest that stream runoff and nitrate loadings will change during future emission scenarios (i.e. longer growing seasons and higher winter precipitation rates). Understanding the timing and magnitude of hydrological and hydrochemical responses is important because climate change effects on catchment hydrology may alter how nitrate is retained, produced, and hydrologically flushed in headwater ecosystems with implications for aquatic metabolism, nutrient export from catchments, and downstream eutrophication.

Sebestyen, S. D.; Shanley, J. B.; Boyer, E. W.; Kendall, C.

2009-05-01

376