bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of pH on the Distribution and Occurrence of Aquatic Fungi in Six West Virginia Mountain Streams
Authors: Dubey Tara , Stephenson Steven L. , Edwards Pamela J. 
Published: July 2010

AbstractAquatic fungi in six streams located on or near the Fernow Experimental Forest in Tucker County, West Virginia, were studied during the 1991 and 1992 growing seasons. Water pH was >5.9 in three of the streams, while the others were more acidic, with average pH = 4.2, 3.9, and 3.2. Sampling methods included (i) isolating conidia from stream water using membrane filtration, (ii) placing bags containing leaves of four tree species in the streams for periods ranging from 2 to 16 wk, and (iii) baiting the streams with various types of other organic material. The stream mycoflora included 156 taxa (47 zoosporic fungi [chytridiaceous fungi and water molds] and 109 hyphomycetes [60 Ingoldian and 49 non‐Ingoldian forms]). Twenty‐seven taxa of zoosporic fungi were recorded from the stream with the highest pH (7.9); only 15 to 18 taxa were collected from other streams. Based on conidia filtered from water samples, the number of taxa of hyphomycetes generally was lower in streams with low pH; however, fewest conidia were recorded at the two extremes of the pH gradient. Northern red oak (Quercus rubra L.) leaves were colonized by an average of 16.0 hyphomycete taxa in the six streams, sugar maple (Acer saccharum Marsh.) by 15.3 taxa, and mixed red maple (A. rubrum L.), and American beech (Fagus grandifolia Ehrh.) by 15.2 taxa. For all three types of leaves, more taxa generally were present in the less acidic streams and fewer in the more acidic streams.
Uptake of Cesium‐137 by Crops from Contaminated Soils
Authors: Demirel H. , Özer I. , Çelenk I. , Halitligil M. B. , Özmen A. 
Published: July 2010

AbstractThe Turkish tea crop was contaminated following the Chernobyl nuclear accident. Finding ways to dispose of the contaminated tea (Camellia sinensis L.) without damaging the environment was the goal of this research conducted at the Turkish Atomic Energy Authority (TAEA). In this study, an investigation was made of 137Cs activities of the plants and the ratios of transfer of 137Cs activity to plants when the contaminated tea was applied to the soil. Experiments were conducted in the field and in pots under greenhouse conditions. The activities of the tea applied in the field ranged from 12 500 to 72 800 Bq/m2, whereas this activity was constant at 8000 Bq/pot in the greenhouse experiment. The transfer of 137Cs from soil to the plants was between 0.037 and 1.057% for wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), corn (Zea mays indentata Sturt), bean (Phaseolus vulgaris L.), lettuce (Lactuca sativa L.), and grass (Lolium perenne L.). The ratio of the transfer of 137Cs activity to plants increased as the activity 137Cs in tea applied to soil was increased. The activity in the plants increased due to increased uptake of 137Cs by plants.
Radionuclide Transport above a Near‐Surface Water Table: I. An Automated Lysimeter Facility for Near‐Surface Contaminant Transport Studies
Authors: Burne S. , Wheater H. S. , Butler A. P. , Johnston P. M. , Wadey P. , Shaw G. , Bell J. N. B. 
Published: July 2010

AbstractThe design and operation is described of a field lysimeter experimental facility to investigate the migration in vegetated soils of contaminants from near‐surface groundwater. Automatic control systems in auxiliary buffer tanks were used to maintain fixed water table depths of 35 and 65 cm, respectively. A cocktail of radionuclides, consisting of 137Cs, 109Cd, 60Co, 22Na, 36Cl, and 99Tc, was introduced to an inert substrate below the water table and recirculated to provide uniform groundwater concentrations. Continuous monitoring was undertaken of water imports/exports, the vertical distribution of soil water potential and soil temperature, and climatological variables. Regular measurements were made of soil moisture content, crop root distribution, crop height and leaf area index, as well as radiochemical concentrations in groundwater and the control system. Intensive radiochemical analyses were made on soil cores and crop. Hydrological results for 1990 and 1991 show a strong contrast in climatic conditions between the 2 yr. Radiochemical data are presented in an accompanying paper.
Radionuclide Transport above a Near‐Surface Water Table: II. Vertical Distribution of Gamma Activities within Soil Profiles in Relation to Wheat Rooting Density and Soil‐to‐Plant Transfers
Authors: Wadey P. , Shaw G. , Bell J. N. , Minski M. J. 
Published: July 2010

AbstractRadiochemical results are described from a replicated field lysimeter experiment to investigate the upward migration of radionuclides in vegetated soils above near‐surface contaminated groundwater. Water tables were maintained at depths of 35 cm (shallow) and 65 cm (deep), below which a cocktail of radionuclides including 137Cs, 109Cd, 60Co, and 22Na was introduced. Results of the vertical migration and plant uptake are presented from the first 2 yr of an ongoing experiment with winter wheat (Triticum aestivum L.). As expected, 137Cs, 60Co, and 109Cd proved to be highly sorbed to the soil solid phase in the regions of the water table and exhibited a lesser degree of up‐profile transport than 22Na in shallow lysimeters. However, in deep lysimeters, 137Cs and 60Cs appeared to be preferentially accumulated at the soil surface; a biological translocation mechanism is postulated to account for this observation. It was clear from a statistical analysis of vertical radionuclide distributions that, in physicochemical terms, 22Na was the most mobile of the radionuclides studied. The distribution of this radionuclide within the soil profiles showed a significant shift between the two growth seasons examined, whereas the distributions of the other radionuclides remained static between 1990 and 1991. Each radionuclide showed a distinct and consistent distribution pattern throughout the crop tissues, although the differences in tissue specific activities for individual radionuclides were found to be nonsignificant with the exception of 22Na. Soil‐to‐plant transfer factors (TFw) were calculated using mean soil specific activities weighted according to the fractional abundance of roots and measured soil specific activities in discrete soil layers. The TFw values were significantly lower in 1991 than in 1990 in both shallow and deep lysimeters; it is postulated that this was due to a much greater fiux of water through the crop in 1990, which was characterized by high evapotranspiration rates and a substantial negative water budget. In both years, TFw values were, in general, significantly higher for deep lysimeters than for shallow lysimeters. This is thought to provide evidence of enhanced radionuclide absorption by the relatively small fraction of roots in the vicinity of the deeper water table.
Usefulness of Selenium for the Reduction of Mercury Emmission from Crematoria
Authors: Hogland William K. H. 
Published: July 2010

AbstractIn Sweden there are no legislative regulations regarding mercury in fluegas emission from crematoria. The crematoria do not have treatment facilities to reduce mercury emissions, although they are the third highest emission source of mercury in Sweden. Included in this paper are the data on mercury emission during cremations with and without the addition of selenium for the reduction of mercury emission. Tests were carried out during 22 cremations. The use of selenium gave emission reductions of 80 to 85% in stack gases, and 20 to 50% in the emission peaks.
Fluometuron Sorption and Transport in Dundee Soil
Authors: Gaston L. A. , Locke M. A. 
Published: July 2010

AbstractThe mobility of a synthetic organic compound in soil is affected by degradation and sorption reactions. Sorption is often a nonequilibrium process, leading to greater mobility and increased potential for contamination of shallow groundwater. Accordingly, this study was undertaken to examine sorption kinetics of the herbicide fluometuron [N,N‐dimethyl‐N′‐[3‐(trifluoromethyl)‐phenyl]urea] in Dundee silty clay loam (fine‐silty, mixed, thermic Aeric Ochraqualfs), a common soil in the Mississippi Delta. Batch experiments indicated sorption equilibrium was achieved by 72 h contact time. Other data suggested little degradation of fluometuron within this time. The approach to equilibrium was characterized by an initially very rapid reaction, followed by a slower rate of sorption. This behavior could be equally well described by either a nonlinear two‐site equilibrium/kinetic or equilibrium/diffusion model. Reaction parameters determined from the batch experiments were further validated by use in a transport model to predict fluometuron movement in this soil. Within parameter uncertainty, the two‐site equilibrium/kinetic model gave accurate predictions of fluometuron mobility. Explicitly modeling time‐dependent sorption as a diffusion process offered minor improvement in transport predictions.
Sewage Sludge Application Effects on Runoff Water Quality in a Semiarid Grassland
Authors: Harris‐Pierce R. L. , Redente E. F. , Barbarick K. A. 
Published: July 2010

AbstractOne of the concerns of land application of sewage sludge (also referred to as biosolids) to rangeland is its effect on the amount and quality of runoff water. In this study, we applied three treatments consisting of 0, 22, and 41 Mg ha−1 of municipal sewage sludge to Larim gravelly sandy loam (Ustollic Arginstoll) and Altvan sandy loam (Aridic Argiustoll) soils in paired plots on two slope gradients (8 and 15%). We used a one‐time application of simulated rainfall for 30 rain at a rate of 100 mm h−1 and collected and analyzed the runoff. We found greater sediment loads in the runoff on 8% slopes due to the larger amount of line soil particles (<2‐mm diam.) in the soil compared with 15% slopes. As sludge rate increased from 0 to 41 Mg ha−1, decreasing concentrations (P < 0.05) of Al (0.55–0.26 mg L−1) and Fe (0.29–0.15 mg L−1) in unfiltered samples of runoff water resulted. Increasing sludge rate from 0 to 41 Mg ha−1 increased (P ≤ 0.05) sediment (0.5–1.0 g L−1), organic N (0.5–25 mg L−1), NH4‐N (0.5–76 mg L−1), and total Na (6.6–10.4 mg L−1), K (4.8–24.8 mg L−1), B (0.016–0.70 mg L−1), P (0.4–15.8 mg L−1), Cu (0.007–0.62 mg L−1), Ni (0.006–0.50 mg L−1), and Mo (0.005–0.52 mg L−1). Concentrations of all measured constituents in the runoff water were less than USEPA standards for drinking water and recommended levels for livestock water.
Effects of Acidification on Bryophyte Communities in West Virginia Mountain Streams
Authors: Stephenson Steven L. , Studlar Susan Moyle , McQuattie Carolyn J. , Edwards Pamela J. 
Published: July 2010

AbstractBryophytes (mosses and liverworts) are often more responsive to water chemistry changes than are vascular plants. In this study, the relationships of bryophyte communities to stream pH and water chemistry were studied, using six streams on or near the Fernow Experimental Forest in Tucker County, West Virginia. Streams were surveyed with line transects using stratified random sampling. Bryophyte communities, based on species composition and structure, fell into three groups, corresponding to basic, moderately acidic, and very acidic stream water. For streams with sandstone beds, species diversity declined with decreasing pH, and no bryophytes were present at pH 3.15. The dominant species in moderately acidic to highly acidic streams is Scapania undulata, a species found to have exceptional tolerance to high acidity and toxic metal levels in Europe and Japan. Scapania undulata was transplanted from a stream with a pH of 5.97 to one with a pH of 3.15. In 3 mo, ultrastructural damage was observed. Acidity (pH) probably was not the only factor involved in controlling species composition and cell ultrastructure, since the two most acidic streams are subject to acid mine drainage and have very high concentrations of dissolved solids, particularly SO4 and Al. Other trace metals commonly associated with acidic surface waters also may have contributed to the differences in species composition.
Soil Phosphorus as a Potential Nonpoint Source for Elevated Stream Phosphorus Levels
Authors: Abrams M. M. , Jarrell W. M. 
Published: July 2010

AbstractEroded soils, as a potential nonpoint P source, have come under scrutiny, particularly in agricultural watersheds. Surface water and groundwater in the Tualatin River Basin (TRB) of Northwestern Oregon have maximum concentrations of 2.1 and 2.6 mg P/L, respectively. We hypothesized that TRB soils are a major P source in the basin because of their high native soil P concentrations and soil P adsorption characteristics. We sampled eight soil series from both lowland and upland positions in the TRB, with both andic and nonandic mineralogy. All soils sampled had high total P concentrations (660–2304 mg P/kg soil). High average extractable P (Bray P1, 74 mg P/kg soil, and ammonium bicarbonate, 35.7 mg P/kg soil) concentrations were found primarily in lowland, nonandic soils. There was no significant difference between P sorption maxima; however, P affinity was significantly higher in upland soils (0.19 L/mg P) than in lowland soils (0.04 L/mg P). Upland, andic soils, due to their erosion potential and high TP levels (average of 1889 mg P/kg soil), could be a P source for surface waters. Lowland, nonandic soils, due to their high extractable P concentrations and lower P sorption affinity, could be a source for both surface and groundwater. Thus, all soils studied, comprising approximately 50% of TRB soils, are potential nonpoint P sources in this watershed, indicating that native soil P is a potential source of nonpoint P pollution.
Precipitation Chemistry along an Inland Transect on the Olympic Peninsula, Washington
Authors: Blew Roger D. , Edmonds Robert L. 
Published: July 2010

AbstractThe objective of this study was to examine oceanic influences, seasonal variation, and effect of distance from the ocean on the chemistry of bulk precipitation falling on the Pacific coast of Washington State. Bulk precipitation was collected at Sites 4, 13, 24, and 31 km inland from the Pacific Ocean. Mean electrical conductivity of precipitation ranged from 0.47 to 1.02 mS m−1 and mean pH ranged from 5.3 to 5.6. Annual precipitation increased from 2780 mm at 4 km to approximately 3500 mm at 13 km from the coast and remained constant through 31 km inland. Precipitation was highest in the late fall and winter months and lowest during the summer. Rates of ion deposition had a similar seasonal pattern to that of precipitation. Concentrations of Cl, SO4, Mg, Na, and excess Ca (Ca in excess of expected sea salt levels) were highest nearest to the coast and were reflected in higher electrical conductivity in precipitation falling closest to the coast. Much of the change in precipitation chemistry occurred between 4 and 13 km from the coast. This corresponds to the change in precipitation and suggests that the changes in chemistry are dilution effects due to increased rainfall. Annual deposition of Na, K, Mg, Ca, excess Ca, NO3, and Cl were lower at the collection site farthest from the ocean. Sulfate deposition remained relatively unchanged with increased distance from the ocean; however, excess SO4 (SO4 in excess of expected sea salt levels) deposition increased and deposition of SO4 from sea salt (total minus excess) decreased with increasing distance from the ocean.
Utility and Railway Rights‐of‐Way Contaminants: Dioxins and Furans
Authors: Wan Michael T. , Van Oostdam J. 
Published: July 2010

AbstractUtility and railway right‐of‐way (ROW) ditches flowing into salmon (Oncorhynchus spp.) streams in the Lower Mainland of British Columbia were sampled in 1990 and 1991 to determine the occurrence and concentrations of selected chlorinated dibenzo‐p‐dioxins (CD) and chlorinated dibenzofurans (CF). Parkland and farmland ditches were also sampled to establish the background concentrations of these chemicals. As well, treated wood utility pole and railway tie samples were collected to confirm the source of CD and CF. Treated wood utility poles contained about 76 700 µg/kg CD and 18 700 µg/kg CF. In railway ties, 13 500 µg/kg CD and 2290 µg/kg CF were found. Although CD and CF were not found in parkland waterways, they were detected in farmland, utility, and railway ROW ditches. Varying mean concentrations of CD (2.2–13 100 ng/L) and CF (0.40–3180 ng/L) were detected in ditch water. In ditch sediments of the same sites, the average CD and CF concentrations ranged from 3.7 to 2580 µg/kg and 0.7 to 1280 µg/kg, respectively. Representative tetra‐, penta‐, hexa‐, hepta‐, and octa‐CD and CF homologs were also detected in ditch water and sediments. Tetra‐CD and tetra‐CF levels found in ditch water adjacent to treated poles did not exceed the 96‐h LC50 (lethal concentration of a chemical to 50% of test organisms) of salmonids and aquatic invertebrate. The biological/toxicological implications to these organisms of high levels of dioxins and furans other than tetra‐CD/CF in sediments and water are discussed.
Plant Litter Decomposition in Wetlands Receiving Acid Mine Drainage
Authors: Kittle D. L. , McGraw J. B. , Garbutt K. 
Published: July 2010

AbstractThe impact of acid mine drainage on the decomposition of wetland plant species of northern West Virginia was studied to determine if the potential exists for nutrient cycling to be altered in systems used to treat this drainage. There were two objectives of this study. First, decomposition of aboveground plant material was measured to determine species decomposition patterns as a function of pH. Second, decomposition of litter from various pH environments was compared to assess whether litter origin affects decomposition rates. Species differences were detected throughout the study. Decomposition rates of woolgrass [Scirpus cyperinus (L.) Kunth] and common rush (Juncus effusus L.) were significantly lower than those of calamus (Acorus calamus L.) and rice cutgrass (Leersia oryzoides L.). Differences among species explained a large proportion of the variation in percentage of biomass remaining. Thus, differences in litter quality among species was important in determining the rate of decomposition. In general, significantly more decomposition occurred for all species in high pH environments, indicating impeded decomposition at low pH. While decomposition of some species litter differed depending on its origin, other species showed no effect. Cattail (Typha latifolia L.), in particular, was found to have lower decomposition rates occurring with material grown at low pH. Lower decomposition rates could result in lower nutrient availability leading to further reduction of productivity under low pH conditions.
Contemporary Groundwater Methane Production from Pleistocene Carbon
Authors: Parkin T. B. , Simpkins W. W. 
Published: July 2010

AbstractRelative to surface systems, microbial activities in groundwater have been poorly studied, especially with regard to methanogenesis. Past studies have reported high concentrations of CH4 in groundwater in the late Wisconsinan till and Wisconsinan loess of central Iowa. The objectives of this work were to assess whether CH4 is presently produced in the till and loess, and, if so, to characterize the spatial variability of CH4 production rates. Groundwater and sediment sampies were collected at several locations within the Des Moines Lobe in central Iowa. Methane concentrations in groundwater ranged from 0.04 µmol L−1 at 1 m to 2600 µmol L−1 at 7 m. Incubations of deep sediment obtained from core samples revealed active CH4 production was occurring, although high variability was observed. Highest specific CH4 production rates were associated with buried particulate C fragments of Wisconsinan age. Results of our study indicate methanogenesis is an active process in the sediments beneath the Des Moines Lobe, that the substrate for methanogenesis is of late Wisconsinan age, and that the high spatial variability of CH4 production is controlled by the heterogeneous distribution of particulate organic C fragments in the glacial sediments.
Fecal Bacteria in Agricultural Waters of the Bluegrass Region of Kentucky
Authors: Howell J. M. , Coyne M. S. , Cornelius P. 
Published: July 2010

AbstractAgricultural runoff influenced by nonpoint pollution frequently exceeds the USEPA standards for bacterial contamination of primary contact water (200 fecal coliforms/100 mL). Few studies have evaluated the effect of cattle (Bos taurus) grazing on fecal contamination of ground water in the karst topography of central Kentucky. Our objectives were to: (i) observe the extent and pattern of fecal bacteria in agricultural waters from two central Kentucky watersheds; (ii) determine if monthly sampling accurately assessed the extent and variability of fecal contamination; and (iii) assess the fecal coliform/fecal streptococci ratio (FC/FS) as an indicator of fecal bacteria source. Springs, streams, and wells in two agricultural watersheds typical of central Kentucky were monitored for fecal coliform and fecal streptococci from December 1991 to January 1993. Springs and wells exceeded primary contact water standards, between 28 and 74% of the time; streams exceeded water quality standards between 87 and 100% of the time. When fecal bacteria were present, rainfall rapidly moved them from the soil surface into spring and well water. At two springs in Fleming county, only 29% of samples exceeded primary contact standards before cattle were present; 80% exceeded standards after cattle began grazing the surrounding pasture. Monthly sampling adequately reflected the extent of fecal contamination in our study, which had relatively continuous cattle grazing. Although the FC/FS ratio identified domestic animal contamination sources, it did not distinguish between domestic animal and human sources of contamination.
Environmental Impacts of Dryland Residue Management Systems in the Southern High Plains
Authors: Jones O. R. , Smith S. J. , Southwick L. M. , Sharpley A. N. 
Published: July 2010

AbstractIncreased use of agricultural chemicals with no‐tillage (NT) may negatively impact the environment through chemical or nutrient loss in runoff or by leaching below the root zone. We compared environmental impacts of NT and the lower chemical input stubble mulch (SM) management methods for dryland crop production on a clay loam soil in a semiarid environment. We measured runoff volume and sediment, nutrient, and triazine concentrations in runoff for 9 yr from seven field‐sized watersheds (2‐5 ha each) cropped in a dryland winter wheat (Triticum aestivum L.)‐grain sorghum [Sorghum bicolor (L.) Moench]‐fallow sequence with SM or NT management with no N or P fertilizer added. We analyzed soil cores to a 6‐m depth for NO−3‐N and to a 3‐m depth for atrazine and propazine content. Adoption of NT management reduced sediment loss by 54% compared with SM, although annual runoff was 15 mm yr−1 greater from NT. Nutrient concentrations and losses (NO−3‐N, NH+4‐N, TN, soluble P, biologically available P, TP) in runoff were extremely small from both tillage systems (losses <3 kg N and <1 kg P ha−1 yr−1) on these unfertilized watersheds. Atrazine [6‐chloro‐N‐ethyl‐N′‐(1methylethyl)‐1,3,5‐triazine‐2,4‐diamine] did not accumulate in the soil or leach below the root zone. Maximal losses of atrazine and propazine in runoff were 0.26 and 1.5% of total application, respectively. Propazine [6‐chloro‐N,N′‐bis(1‐methylethyl)‐1,3,5‐triazine‐2,4‐diamine], applied to both NT and SM sorghum when runoff is probable, appears to have a greater potential for negatively impacting the environment under semiarid conditions than does atrazine, which is applied when runoff probability is small. Propazine accumulated in the soil profile but was undetected below 0.6 m. Perhaps the most detrimental impact of adopting NT management was increased leaching of NO−3‐N to depths below the plant root zone as a result of wetter soil and improved water conservation with NT in the semiarid environment.