bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cadmium and Lead Deposition around a Swedish Battery Plant as Recorded in Oak Tree Rings
Authors: Eklund Mats 
Published: July 2010

AbstractIn this study, results from the elemental analysis of Cd and Pb in oak (Quercus robur L.) tree rings are compared with emission estimations based on company and official statistics for the major producer of Ni‐Cd accumulators in Sweden, NIFE. The NIFE plant in Fliseryd was in operation from 1910 to 1974, handling and thereby emitting large quantities of Cd. In 1942, the company also took up recycling Pb from various sources. The Cd and Pb content in control trees, situated far from point sources, varied between 20 and 30 µg/kg without any obvious temporal trend for Cd and 20 to 200 μg/kg with an increasing temporal trend for Pb during the 20th century. These values represent regional background levels resulting from natural and diffuse sources. Cores from 18 trees, situated less than 2 km away from the factory were sampled. The variation in absolute figures between different trees was in some cases large, but the temporal trend within each tree showed a consistent similarity to the trend of the estimated emissions. The Cd values were up to one magnitude higher than in the reference trees, and the highest values were always found in the latest segment, formed from 1980 to 1990. A significant uptake through the roots from the polluted soil after the factory close down must therefore have taken place. The Pb content of the sampled trees in a few cases exceeded 3000 μg/kg, but the highest values were never found in the latest 10‐yr segment. Despite large intertree variation and difficult interpretations, the tree‐ring analysis seems to have great potential as a tool for the study of both temporal and spatial dimensions of historical Cd and Pb emissions.
Old and New Water in Subsurface Flow from a Forest Soil Block
Authors: Turton Donald J. , Barnes Donald R. , de Jesus Návar Jose 
Published: July 2010

AbstractIn order to understand how infiltrating water mixes with water and solutes already present in the soil, percentages of old and new water in subsurface flow from a forest soil block subjected to simulated rainfall were studied. A rainfall simulator was used to apply simulated rainfalls of four intensities 6.3, 4.3, 2.8, and 1.3 cm h−1. Each intensity was repeated four times. Sodium bromide was added to the first replicate, but not the two following replicates to insure that old and new water had different chemical signatures. Subsurface flow was measured at four depths, 14, 26, 44, and 64 cm using a system of collection troughs and tipping buckets. Discrete water samples for bromide analysis were taken at 1‐ to 10‐min intervals throughout each simulation. Old water percentages declined as the block was wetted and reached a minimum when peak subsurface flow was achieved. Minimum old water percentages during the simulations ranged from 0% for the 6.3 cm h−1 simulation to 28% for the 1.3 cm h−1 simulation. After rainfall stopped subsurface flow declined rapidly and old water percentages increased. Total subsurface flow was composed of 8.0, 3.7, 3.9, and 31% old water for simulated intensities of 6.3, 4.3, 2.8, and 1.3 cm h−1, respectively, indicating a trend of increasing old water with decreasing rainfall intensity. Rapid subsurface flow through soil macropores was the most likely mechanism of new water release.
Numerical and Field Evaluation of Soil Water Sampled by Suction Lysimeters
Authors: Wu L. , Baker J. M. , Allmaras R. R. 
Published: July 2010

AbstractPorous cup suction‐lysimeters are widely used for extracting soil water in solute transport monitoring, bat it is not clear how the sampled concentration can change with the ambient solute concentration, or with applied suction inside the lysimeter. This research was designed to numerically evaluate soil water sampled by suction lysimeters and to test simulation results with field observations. An axisymmetric three‐dimensional finite element model (SWMS_2D) was used to simulate soil water sampled by suction lysimeters in a Zimmerman fine sand (mixed, frigid Argic Udipsamments). To test the simulated results, KBr was uniformly spread on the soil surface. After 183 mm rainfall, suction was applied to the lysimeters (with ceramic cups at a depth of 0.8 m) to withdraw soil water; soil column samples were also removed from the surrounding soil and sectioned to determine solute concentration in situ using a bromide electrode. Simulation showed that when there is a concentrated solute band near a porous cup, as can occur with banded fertilizers, the concentration of sampled soil water in the lysimeter is considerably higher than the resident concentration in the soil at the same depth. The influence of a concentrated solute band on the concentration of sampled soil water decreased as the distance to the cup increased. Variations in applied suction (25, 35, and 45 kPa) appear to have little influence on the amount and concentration of field lysimeter extracted soil water. The measured amount of water in the lysimeter (78.4 mL) was comparatively more than the simulated amount (53.9 mL) when the mean water content of nine soil columns was used as an initial condition for the simulation, but was within the range of simulated amounts (32.5–91.5 mL) when the lower and upper 95% limits of the measured soil‐water content profiles were used as initial conditions for the simulations. Measured Br− concentration of the sampled water (3.13 × 10−4 M) was lower than the simulated concentration (4.66 × 10−4 M) when the geometric means of each layer from the nine soil column Br− concentrations were used as the initial conditions. The difference between measured and simulated concentration may have been due to variability in soil hydraulic properties.
Physical Characteristics of Alkaline Stabilized Sewage Sludge (N‐Viro Soil) and Their Effects on Soil Physical Properties
Authors: Logan T. J. , Harrison B. J. 
Published: July 2010

AbstractThe N‐Viro process for alkaline stabilization of municipal sewage sludge combines dewatered sludge with one or more alkaline industrial byproducts and destroys pathogens by a combination of high pH, heat, and drying. The final product, N‐Viro Soil, is a soil‐like material that is being used as an agricultural lime substitute, soil amendment, and soil substitute. Physical characteristics of 28 N‐Viro Soils were determined and compared to those of mineral soils. The N‐Viro Soils have an average solids content of 62%, particle density of 1.96 Mg/m3, bulk density of 0.59 Mg/m3, and total porosity of 70%. Mean moisture retention was 66, 58, 34, and 31% (v/v) at saturation, 5.9, 33, and 1.5 MPa, respectively. Available water content was 27% by volume (60 cm water tension, 1.5 MPa). Noncompacted and compacted saturated hydraulic conductivities were high, 3 × 10−2 and 9 × 10−4 cm/s, respectively. Mean weight diameter (MWD) of water stable aggregates was 2.0 mm. Fifty‐six percent of the materials were >2 mm in diam., almost all of this (88%) in sizes <16 mm. Of the <2‐mm fraction, 69% was >0.5 mm. The N‐Viro Soils have a shrinkage of 58%, and Atterberg liquid limit, plastic limit, and plasticity index of 76, 64, and 18% water (w/w), respectively. The N‐Viro Soils are similar in physical attributes to those of medium to fine textured, porous soils with granular, stable aggregates, and nonplastic consistency. The moisture retention characteristics are those of a fine textured soil dominated by fine pores and low to medium available water holding capacity, and these materials are highly permeable, even when compacted. N‐Viro Soil was applied to the Miamian silt loam (fine, mixed, mesic Typic Hapludalf) in the field at a rate of 500 Mg/ha (dry solids), and changes in physical properties were measured 1 yr after application. All effects of N‐Viro Soil were statistically significant (P = 0.01), except total porosity, 33 KPa moisture holding capacity, 0.5‐ to 0.25‐mm water stable aggregates, and pocket penetrometer measurements, and all of the effects were beneficial.
Minespoil Amendment with Dry Flue Gas Desulfurization By‐Products: Element Solubility and Mobility
Authors: Stehouwer R. C. , Sutton P. , Fowler R. K. , Dick W. A. 
Published: July 2010

AbstractGreenhouse column studies of 8 mo duration investigated the solubility and mobility of salts and trace elements in dry flue gas desulfurization (FGD) by‐products used for minespoil reclamation. Three minespoils were amended with two dry FGD by‐products (lime injection multistage burners ash, LIMB; and, pressurized fluidized bed combustion ash, PFBC) using amounts from 0 to 320 g k−1. Two of the minespoils also received sewage sludge amendment of 60 g kg−1. Columns were planted with ‘Kentucky 31’ tall fescue (Festuca arundinacea Schreber). Leachate analyses and pH determinations from column mixes were done at the beginning and the conclusion of the experiments. Both FGD by‐products were effective in raising pH of the spoil materials. The largest LIMB amendment raised pH to near 12 and resulted in the formation of ettringite [(Ca6Al2(SO4)3(OH)12·26 H20)]. Leachate pH, electrical conductivity, dissolved organic C, Ca, Mg, and S tended to increase with increased FGD amendment, while Al, Fe, Mn, and Zn decreased. Changes in leachate As, B, Cu, Ni, and Se depended on interactions among the type of FGD, the type of spoil, and the presence of sewage sludge, with pH being the most important variable. Overall, with FGD amendments of 120 g kg−1 or less, leachate concentrations of most elements of environmental concern were less than drinking water standards. The amount of FGD by‐product that can be applied to a minespoil is probably limited by soluble salts and initially high pH levels rather than by trace element loading of spoil or water.
Urban Waste Compost: Effects on Physical, Chemical, and Biochemical Soil Properties
Authors: Giusquiani P. L. , Pagliai M. , Gigliotti G. , Businelli D. , Benetti A. 
Published: July 2010

AbstractA long‐term field experiment was conducted to determine the effect of the additions of urban waste compost on the physical and chemical properties and enzymatic activities in a calcareous soil (Fluventic Xerochrept). Total porosity (pores >50 µm measured on thin soil sections from undisturbed samples by image analysis) was greater in the plots treated with compost than the control plots due to a larger amount of elongated pores. In the amended plots total and humified organic C, Pb, Cu, and Zn showed a significant increase compared with nonamended plots. Enzymatic activities (L‐asparaginase, arylsulphatase, dehydrogenase, phosphodiesterase, and alkaline phosphomonoesterase) were significantly enhanced by the compost addition thus indicating no inhibiting influence of the heavy metals present. The increased levels of the arylsulphatase, dehydrogenase, phosphodiesterase, and phosphomonoesterase activities were significantly correlated with total porosity: the first three with pores ranging from 50 to 1000 µm, mainly with pores 50 to 200 µm in size, and phosphomonoesterase only with pores whose size was <500 µm. L‐asparaginase activity was not correlated with porosity. Only arylsulphatase, dehydrogenase, and phosphodiesterase were negatively correlated with bulk density.
Model for Biomethylation and Volatilization of Selenium from Agricultural Evaporation Ponds
Authors: Gao Suduan , Tanji Kenneth K. 
Published: July 2010

AbstractSelenium has evapoconcentrated to hazardous levels in agricultural evaporation ponds in the San Joaquin Valley of California. Microbial methylation and volatilization is one of the pathways by which high Se concentrations may be dissipated from these ponds. To obtain a more complete understanding of this potential remediation process, kinetic models are developed to evaluate the factors affecting Se biomethylation such as temperature and organic C sources (carbohydrates and proteins) using experimental data from the literature. By assuming that dimethylselenide (DMSe, (CH3)2Se) formation is irreversible and follows first‐order kinetics, the experimental data are described reasonably well using temperature‐ and organic matter‐characteristics, except deviations occurred at a higher temperature (35°C). Proteins are known to stimulate Se volatilization dramatically as compared with carbohydrates as the energy source. This stimulatory property appears to depend on the ability of microorganisms to absorb protein hydrolysis products, a source of methyl groups. A coupled reaction mechanism is proposed in which proteins provide methyl groups for Se methylation to form volatile DMSe. The model fitted experimental data successfully. The volatility of DMSe through the air‐water interface was evaluated using a two‐layer film model. The predicted half‐life of DMSe in water ranged from 1 to 3 d when assuming that wind speed was <3 m s−1 and the water body was 1 m deep. An opportunity exists to enhance Se volatilization by fungi, bacteria, microalgae, and other indigenous microbes found in evaporation ponds as a remediation technique. Additional knowledge on the fate of DMSe both in the water and in the atmosphere, however, is needed to evaluate this dissipation strategy in high Se water bodies.
Persistence and Fate of Anthracene and Benzo(a)pyrene in Municipal Sludge Treated Soil
Authors: Goodin J. D. , Webber M. D. 
Published: July 2010

AbstractGreenhouse studies using pots and microcosms were conducted to investigate the persistence and fate of nonlabeled and 14C‐labeled anthracene (ANT) and benzo(a)pyrene (B(a)P) in sludge treated soil. Results indicated that ANT degraded rapidly (t1/2 ≈ 3 wk) from the experimental systems, but that B(a)P was persistent. Cropping did not affect the persistence of either compound. On completion of the experiments (≤21 wk), ≤ 10% of the ANT added to soil was recovered intact, whereas 78% of the B(a)P added to soil was recovered intact. Most (≥ 85%) of the 14C added to soil as labeled ANT and B(a)P was accounted for. Recoveries of 14CO2 indicated significant mineralization of ANT, but not of B(a)P. Trivial amounts (≤0.2%) of were recovered as volatile organics and in plant materials, but large amounts were recovered from soil. A considerable proportion of the ANT derived 14C in soil was not extracted with acetone/hexane, which indicated that it had been converted to bound residue. A much smaller proportion of B(a)P than of ANT derived 14C in soil was converted to bound residue. No evidence was obtained for uptake of intact ANT or B(a)P by ryegrass (Lolium multiflorum Lam.), soybean [Glycine max (L.) Merr.], and cabbage (Brassica oleracea var. capitata L.).
Cause and Remediation of Hydrogen Sulfide Emissions from a Sodium‐Based Flue Gas Desulfurization Sludge Disposal Pond
Authors: Ainsworth C. C. , Rai D. , Smith S. C. 
Published: July 2010

AbstractA flue gas desulfurization (FGD) sludge disposal pond with a history of H2S emissions to the atmosphere was studied to determine the cause of emissions and remediation strategies. The pond receives sludge and associated waters from a single‐pass Na2CO3 flue gas scrubber unit. The pond water is a sodic alkaline brine with large SO3 and S2O3 concentrations (>5000 mg L−1), and hence, an elevated chemical O2 demand. The pond water H2S concentrations are small as a result of periodic H2O2 additions. The sediments, however, have as much as 3500 mg L−1 H2S in the pore water. The production of H2S appeared to originate from the sediments and diffuses through the anoxic water column with little oxidation. Large concentrations of the reduced sulfur species SO3 and S2O3 were present as a result of the flue gas desulfurization process and incomplete oxidation of H2S. The pond was reconstructed to circulate the water through an air injection system that was designed to oxidize the SO3 and S2O3 to SO4, and thereby reduce the chemical O2 demand. After the installation of the air injection system, emissions of H2S ceased and the concentrations of SO3 and S2O3 were reduced by at least a factor of 10 within 3 to 4 wk. The production of H2S in the sediments, however, did not appear to be affected, nor did it appear that it will be reduced in the future by the air injection system.
Effect of Chemical Amendments on Ammonia Volatilization from Poultry Litter
Authors: Moore P. A. , Daniel T. C. , Edwards D. R. , Miller D. M. 
Published: July 2010

AbstractAmmonia (NH3) volatilization from poultry litter results in a buildup of atmospheric NH3 in chicken houses, which is detrimental to both farm laborers and birds. Ammonia loss from litter is detrimental to the external environment because it results in acid rain, as well as low N/P ratios in litter, which increase the likelihood of excessive P runoff into adjacent water bodies. The objectives of this study were to determine the effect of various chemical amendments on NH3 volatilization and selected litter characteristics after 42 d. A laboratory study was conducted using the following amendments: Ca(OH)2 (calcium hydroxide), Al2(SO4)3·18H2O (alum), alum + CaCO3, FeSO4·7H2O (ferrous sulfate), and MLT (Multi‐purpose Litter Treatment, commercial product). Ammonia‐free air was continuously passed through air‐tight chambers containing amended litter and any NH3 volatilized from the litter was trapped in boric acid solutions, which were titrated daily for NH3 content. The study was carried out for 42 d. At this time, the litter was analyzed for pH, electrical conductivity (EC), soluble, organic C (SOC), metals, and soluble and total forms of N and P. The results of this study indicated that the addition of alum to poultry litter dramatically reduces NH3 volatilization (up to 99% less volatilization than controls). Decreases in volatilization resulted in higher total and soluble N in litter, which increased N/P ratios. Several of the compounds studied (particularly alum) were effective in decreasing water‐soluble P levels in litter. Therefore, we are proposing the use of alum as a litter amendment in poultry houses.
Aerobic Acetate Degradation near the Capillary Fringe of Roadside Soil: Field Simulations from Soil Microcosms
Authors: Ostendorf D. W. , DeGroot D. J. , Pollock S. J. , Gagnon P. J. 
Published: July 2010

AbstractWe studied the aerobic degradation of acetate in a roadside soil to assess the reduction of O2 demand imposed by an alternative highway deicing agent on groundwater. Aseptic uniform sand samples adjacent to the capillary fringe of a state highway shoulder in southeastern Massachusetts were placed in sterile serum bottles at 5°C, forming a series of aerobic soil microcosms. The samples were dosed with a reagent‐grade glacial acetic acid solution, then sampled at various time intervals and analyzed by ion chromatography in a laboratory determination of the microbial degradation kinetics. The aerobic reaction rates were slower than those observed in loamy sand near the ground surface in an earlier study. A steady state transport model for the alternative highway deicing agent calcium magnesium acetate [CMA; Ca0.3 Mg0.7(C2H3O2)2] was derived, including infiltration and degradation. Simulations were run using the observed microcosm kinetics for a range of assumed snowmelt rates. The resulting profiles suggest that microbial activity within the uniform sand near the capillary fringe has the potential to reduce O2 demand by CMA on groundwater for slow (<5×10−7 m/s) snowmelt rates at 5°C under aerobic conditions. More rapid infiltration passes more CMA to the underlying aquifer.
Soil Water Balance Changes in Engineered Soil Surfaces
Authors: Sackschewsky M. R. , Kemp C. J. , Link S. O. , Waugh W. J. 
Published: July 2010

AbstractPermanent disposal of radioactive waste requires the construction of isolation barriers that minimize both recharge and erosion. Recharge can be prevented by storing precipitation near the surface so that it will be returned to the atmosphere via evapotranspiration. Erosion can be reduced with gravel mulch, but thick gravel layers may increase recharge. Gravel mixed into the surface soil may provide erosion protection without increasing recharge. To compare the effects that erosion control has on infiltration, two lysimeter experiments were conducted to examine the effects of sand and gravel mulches and gravel admixtures, using two precipitation regimens and with or without vegetation. Sand and gravel mulch increased soil‐column water storage and decreased evapotranspiration compared with a plain soil surface. Gravel admixtures did not significantly affect the soil water balance compared with plain soil surfaces. Vegetation increased evapotranspiration and decreased soil moisture storage compared with nonvegetated treatments. Irrigation greatly increased evapotranspiration but had little effect on soil water storage. Drainage was detected from sand and gravel‐mulch lysimeters, but not from lysimeters with a plain‐soil or gravel‐admixture surface. Results are significant for isolation barrier designs in arid sites: (i) a nonvegetated gravel‐mulch surface eventually will result in recharge, even under low precipitation (160 mm/yr); and (ii) a soil column with a plain‐soil or gravel‐admixture surface is capable of recycling all water back to the atmosphere, even under high‐precipitation (450 mm/yr).
Impact of Long‐Term Tillage Systems for Continuous Corn on Nitrate Leaching to Tile Drainage
Authors: Randall G. W. , Iragavarapu T. K. 
Published: July 2010

AbstractInformation is lacking on the long‐term impact of tillage systems on NO3 losses to surface and groundwater. An 11‐yr (1982–1992) study was conducted to assess NO3 losses to subsurface, tile drainage for corn (Zea mays L.) grown with continuous conventional tillage (CT) and no tillage (NT) on a poorly drained Webster clay loam soil (fine‐loamy, mixed, mesic Typic Haplaquoll) at Waseca, MN. Nitrogen was applied at an annual application rate of 200 kg ha−1. Mean annual subsurface drain flow during the 11‐yr period was 35 mm higher for NT (315 ram) compared with CT (280 mm). Flow‐weighted nitrate‐nitrogen (NO3‐N) concentrations increased dramatically in the wet years (1990 and 1991) following the dry period of 1987 to 1989. Flow‐weighted NO3‐N concentrations during the 11‐yr period averaged 13.4 and 12.0 mg L−1 for CT and NT, respectively. Although subsurface drain flow was 12% higher with NT, NO3‐N losses were about 5% higher with CT mainly due to higher NO3‐N concentrations with CT in the last 2 yr. Corn grain yields and N removal were significantly higher in 6 out of 11 yr with CT compared with NT with no difference between tillage systems in the other 5 yr. Grain yields averaged 8.6 Mg ha−1 with CT and 7.3 Mg ha−1 with NT during the 11‐yr period. Multiple regression equations showed that annual flow‐weighted NO3‐N concentration is best predicted from residual soil NO3 in the 0‐ to 1.2‐m profile and spring rainfall while NO3‐N flux can be predicted well from May and June rainfall. Results from this long‐term study indicate that on this poorly drained soil, CT had a positive effect on corn grain yield and N removal compared with NT, but tillage systems had minimal impact on NO3 losses to subsurface drain flow. Higher drain flow with NT does not necessarily result in higher NO3‐N fluxes lost via subsurface drainage.