bluuebunny/crossref_metadata_2025_split huggingface dataset:
Airborne Contamination of Forest Soils by Carbonaceous Particles from Industrial Coal Processing
Authors: Schmidt Michael W. I. , Knicker Heike , Hatcher Patrick G. , Kögel‐Knabner Ingrid 
Published: July 2010

AbstractIn the German Ruhr‐area industrial coal processing emitted large amounts of carbonaceous particles for a century until 1970. Our objectives were to detect the presence of airborne carbonaceous particles and assess their impact on the chemical structure of soil organic matter in two forest soils (Podzols) with potential sources of carbonaceous particles approximately 10 to 30 km away. Contamination was not visible macroscopicaily. Organic matter was characterized in bulk soils and in particle‐size separates by elemental analysis, magnetic susceptibility measurement, reflected light microscopy, and 13C solid‐state nuclear magnetic resonance (NMR) spectroscopy. Organic and mineral horizons contained carbonaceous particles including char, coke, and bituminous coal from coal combustion, coking, coal processing, and steel production. In the organic horizons of both soils we observed a material high in magnetic susceptibility (max. 109 × 10−8 m3 kg−1), whereas in the mineral horizons only the Podzol with an intense intermixing moder‐type humus had high magnetic susceptibly. This Aeh horizon was extremely rich in organic carbon (139.4 g organic C kg−1), concentrated in the 20 to 2000 µm size separates. In the second Podzol, like in many natural soils, C concentrations were largest in the <20 µm separates. Bloch decay 13C magic angle spinning (MAS) NMR spectroscopy revealed a highly aromatic structure of the carbonaceous particles. Airborne carbonaceous particles formed a macroscopically indistinguishable mixture with natural soil organic matter and could be present in many soils neighboring industrialized areas.
Kinetics of Trichloroethylene Cometabolism and Toluene Biodegradation: Model Application to Soil Batch Experiments
Authors: El‐Farhan Yassar H. , Scow Kate M. , Fan Shifang , Rolston Dennis E. 
Published: July 2010

AbstractTrichloroethylene (TCE) biodegradation in soil under aerobic conditions requires the presence of another compound, such as toluene, to support growth of microbial populations and enzyme induction. The biodegradation kinetics of TCE and toluene were examined by conducting three groups of experiments in soil: toluene only, toluene combined with low TCE concentrations, and toluene with TCE concentrations similar to or higher than toluene. The biodegradation of TCE and toluene and their interrelationships were modeled using a combination of several biodegradation functions. In the model, the pollutants were described as existing in the solid, liquid, and gas phases of soil, with biodegradation occurring only in the liquid phase. The distribution of the chemicals between the solid and liquid phase was described by a linear sorption isotherm, whereas liquid‐vapor partitioning was described by Henry's law. Results from 12 experiments with toluene only could be described by a single set of kinetic parameters. The same set of parameters could describe toluene degradation in 10 experiments where low TCE concentrations were present. From these 10 experiments a set of parameters describing TCE cometabolism induced by toluene also was obtained. The complete set of parameters was used to describe the biodegradation of both compounds in 15 additional experiments, where significant TCE toxicity and inhibition effects were expected. Toluene parameters were similar to values reported for pure culture systems. Parameters describing the interaction of TCE with toluene and biomass were different from reported values for pure cultures, suggesting that the presence of soil may have affected the cometabolic ability of the indigenous soil microbial populations.
Erodibility of Fly Ash Used as a Topsoil Substitute in Mineland Reclamation
Authors: Gorman James M. , Sencindiver John C. , Horvath Donald J. , Singh Rabindar N. , Keefer Robert F. 
Published: July 2010

AbstractFly ash, a by‐product of coal‐fired power plants, has been used successfully in reclaiming abandoned mine lands by improving mine‐soil chemical and physical properties. However, the fine sand‐silt particle size of fly ash may make it more susceptible than natural soils to detachment and transport by erosive processes. Furthermore, the high content of silt‐size particles in fly ash may make it more susceptible to surface crust formation, resulting in reduced infiltration and increased surface runoff and erosion. In the summer of 1989, fly ash‐wood waste mixtures, used as a topsoil substitute, were surface applied on two separate mine sites in Preston County, WV, one with 10% slope and the other 20% slope. Erosion rates were measured directly using the Linear Erosion/Elevation Measuring Instrument (LEMI). Erosion measurements were taken during the first two growing seasons on both sites. Erosion values were up to five times greater on the fly ash‐treated minesoil than on the untreated minesoil. Mulching with wood chips reduced fly ash erosion to about one‐half the loss of the unmulched plots. Erosion was related to both the amount and type of ground cover. Increased vegetative ground cover resulted in reduced erosion. Mosses and fungi appeared to provide better erosion protection than grass‐legume cover.
Effect of Nitrate on Uptake of Pertechnetate by Tomato Plants
Authors: Krijger G. C. , Kollöffel C. , Wolterbeek H. T. 
Published: July 2010

AbstractNitrate has been shown to affect the acquisition of the nuclear waste product technetium (Tc) by plants. The mechanism responsible for this phenomenon is unknown. The uptake of [99mTc]TcO−4, [35S] SO2−4 and H2[32P]PO−4 was studied in tomato plants (Lycopersicon esculentum Mill., cv. Tiny Tim) with different growth rates due to culture at 0.5, 4.0, or 30 mM NO−3. In experiments lasting 24 h, net TcO−4 uptake decreased at higher NO−3 supplies. The inhibitory effect of NO−3 on TcO−4 uptake also was shown in TcO−4 influx experiments (Ki = 3.3 mM), although about 30% of the TcO−4 influx is suggested to be insensitive to NO−3. In contrast, H2PO−4 (30 mM) did not inhibit TcO−4 influx, whereas SO2−4 (30 mM) tended to increase TcO−4 influx, probably due to the ionic strength of the uptake solution. Significant effects of the NO−3 supply on Tc efflux were not found. Overall, this leads to the conclusion that TcO−4 and NO−3 share at least one transporter.
Imazaquin Sorption in Highly Weathered Tropical Soils
Authors: Regitano J. B. , Alleoni L. R. F. , Vidal‐Torrado P. , Casagrande J. C. , Tornisielo V. L. 
Published: July 2010

AbstractImazaqnin is a herbicide used intensively in Brazil to control a large number of weeds associated with soybean [Glycine max (L.) Merr.]. Most of the Brazilian soils are highly weathered (50–60% are Oxisols). The extent of sorption and desorption of imazaquin in these soils will dictate its mobility and environmental fate once microbial degradation is negligible. Sorption and desorption of imazaquin were studied in nine samples (seven surface and two subsurface) from highly weathered soils and in two other soils. Sorption of imazaquin was low in all soils, except in the soil with high organic carbon content (OC) content and low soil‐solution pH (Typic Humaquept, GH soil). The OC and the soil‐solution pH were the soil attributes that correlated better with the amount of sorbed imazaquin in the studied highly weathered soils [r = 0.91 (significant at the 0.01 probability level) and −0.62 (significant at the 0.05 probability level), respectively]. The Fe oxide content was an important soil attribute affecting sorption of imazaquin when OC was low. In general, a model based on hydrophobic interactions was capable of predicting sorption of imazaquin. However, this model and others based on multivariate regression were not capable of predicting sorption of imazaquin on highly weathered soils with pH‐dependent charges and low OC, such as the subsurface acric soils. Low sorption implies a high potential for mobility and, therefore, imazaquin may reach important sources of drinking water. This potential for mobility may be diminished in highly weathered soils due to their acidic nature and high Fe and Al oxide contents.
Phosphorus Solubility in Biosolids‐Amended Farm Soils in the Mid‐Atlantic Region of the USA
Authors: Maguire R. O. , Sims J. T. , Coale F. J. 
Published: July 2010

AbstractThere have been increased environmental concerns about agricultural P management, including land application of biosolids (municipal sewage sludge). This study investigated the influence of current N‐based land application practices for biosolids on soil P. We collected soil samples from 11 biosolids application sites and from adjacent setback areas that had never received biosolids. These samples were analyzed for oxalate‐extractable phosphorus (Pox), aluminum (Alox, and iron (Feox); degree of phosphorus saturation (DPS = (Pox/0.61[Alox + Feox]) × 100), Mehlich‐1 P; iron‐oxide strip extractable phosphorus (FeO‐P); and water‐soluble phosphorus (WSP). In many cases Mehlich‐1 P was excessive (>50 mg kg−1), but this occurred in both application sites and setback areas. Biosolids application sites had significantly greater Pox in the topsoils (0 to 20 cm) when averaged for all sites, with means of 589 and 296 mg kg−1 in the application sites and setback areas, respectively. However, biosolids applications also increased [Feox + Alox], which meant that the DPS was not always increased. There was a trend for higher Pox and FeO‐P in the biosolids‐amended soil profiles (60‐cm depth) and highest P concentrations were consistently found at the 0‐ to 5‐cm depth. The net effect of biosolids applications on Pox, relative to [Feox + Alox], was related to FeO‐P. Our data suggest that adding biosolids according to current N‐based guidelines will lead to an accumulation of P in soils, but the release of this P may be mitigated by the associated increases in soil [Feox + Alox].
Volatilization of Nitrogen from Dewatered Biosolids
Authors: Robinson M. B. , Polglase P. J. 
Published: July 2010

AbstractVolatilization of N from biosolids applied to land lessens the risk of ground water contamination and reduces the amount available for plant uptake. This study determined rates of volatilization of NH+4−N from biosolids after surface‐application. Biosolids from three sewage treatment plants (Cronulla, Liverpool, and Quakers Hill) in Sydney, Australia, were applied under controlled conditions to exclude leaching and plant uptake, and volatilization was calculated using a mass balance approach. Application rates supplied 100 to 168 g m−2 of total N including 20 to 67 g m−2 of NH+4‐N. Most loss of N occurred within 1 wk of application; within 3 wk 71 to 81% of the NH+4−N applied had been lost. Subsequent changes in NH+4−N were small and there was little loss of organic N. The rapidity and magnitude of loss in both NH+4−N and total N suggests that N was primarily lost by volatilization, and that denitrification losses, involving slower biological processes, were minimal. Amounts of NH+4−N volatilized were proportional to amounts applied. Loss of applied NH+4−N did not increase with regular re‐wetting, although loss of total N was increased, suggesting mineralization of organic N followed by gaseous loss. Volatilization, an important pathway for loss of N applied in biosolids, needs to be considered when calculating rates of biosolids application to protect ground water while providing nutritional benefit.
Radiocesium Uptake by One‐Year‐Old Willows Planted as Short Rotation Coppice
Authors: Gommers A. , Thiry Y. , Vandenhove H. , Vandecasteele C. M. , Smolders E. , Merckx R. 
Published: July 2010

AbstractHigh radioactivity concentrations in foodcrops grown in areas contaminated by the Chernobyl accident continue to justify the consideration of a change in land use. Production of biofuel may be one of the alternatives to food production. However, present knowledge about radionuclide cycling in such systems is limited. In the present study, radiocesium uptake and distribution were measured in a willow (Salix viminalis L. var. Orm) short rotation coppice (SRC) stand. This system allows production of energy from the harvested biomass. Experimental plots were established on two soil types of contrasting texture (loamy versus sandy), and contaminated with 8 × 106 Bq 134Cs m−2. Concentrations of 134Cs were measured in wood, litter, roots, and cuttings after 1 yr of growth. At the end of the growing season, only 0.0012% (loamy soil) and 0.0065% (sandy soil) of the initial radiocesium was transferred to the plant biomass (including belowground plant parts). Stem wood contained the lowest concentration of 134Cs among all plant parts analyzed. Wood radiocesium concentrations were 82 Bq kg−1 for the loamy soil and 192 Bq kg−1 for the sandy soil. These values are well below the exemption limit for fuel wood put forward in the Commonwealth of Independent States (CIS) (740 Bq kg−1). Even at this high soil contamination level, radiocesium concentrations in wood do not exceed appreciably the naturally occuring 40K content in the wood (135 Bq kg−1).
Degradation and Volatilization of the Fumigant Chloropicrin after Soil Treatment
Authors: Gan J. , Yates S. R. , Ernst F. F. , Jury W. A. 
Published: July 2010

AbstractChloropicrin (CP) is used in fumigation of soil‐borne pests. Because of its high volatility and toxicity, atmospheric emission of CP during soil application may become a source of air pollution. We investigated degradation of CP in three different soils as a function of soil temperature and moisture conditions, and evaluated its volatilization against methyl bromide (MeBr) from packed soil columns. Chloropicrin degraded much faster than MeBr in the same soil, mainly via microbial degradation. Degradation of CP accelerated as soil temperature increased, but was relatively independent of changes in soil moisture. When the soil surface was uncovered, overall volatilization loss of CP was similar to that of MeBr. Covering the soil surface with a polyethylene or high‐barrier film was much more effective in reducing volatilization of CP than MeBr. Therefore, surface covers may be used in sensitive areas to reduce human exposure to CP.
Groundwater Quality Beneath Irrigated Vegetable Fields in a North‐Central U.S. Sand Plain
Authors: Stites Will , Kraft G. J. 
Published: July 2010

AbstractThe dramatic expansion of irrigated agriculture since about 1970 in the north‐central USA has been accompanied by NO3 and pesticide pollution of groundwater. The expansion has been concentrated in areas with sandy soils and shallow water tables, such as the Wisconsin central sand plain. In some parts of this sand plain, most wells contain detectable pesticide residues and NO3‐N concentrations that exceed the 10 mg L−1 U.S. drinking water maximum contaminant level (MCL). To evaluate the effects on groundwater quality of this agricultural system, we monitored solutes 23 times during a 2‐yr period in the upper 3 m of the aquifer beneath and immediately upgradient of four irrigated vegetable fields. Groundwater beneath fields had significantly greater concentrations of most solutes and lower pH than upgradient groundwater. Especially pronounced were Ca, Cl, K, Mg, and NO3 differences, with concentrations 5 to 26 times greater under fields. Nitrate N concentrations averaged 21 mg L−1 under fields, compared with 1 mg L−1 upgradient. Pesticide residues were ubiquitous beneath fields, and generally persisted for many months after application. Pesticide concentrations often exceeded Wisconsin preventive‐action limits (PALs), but seldom exceeded federal MCLs. Even when agricultural management approximated best management practice (BMP) recommendations, the NO3 concentration beneath these fields approached double the MCL, indicating a need for new approaches to control agricultural groundwater pollution.
Modeling Nitrate Nitrogen Leaching in Response to Nitrogen Fertilizer Rate and Tile Drain Depth or Spacing for Southern Minnesota, USA
Authors: Davis D. M. , Gowda P. H. , Mulla D. J. , Randall G. W. 
Published: July 2010

AbstractThe Agricultural Drainage and Pesticide Transport (ADAPT) simulation model was used to evaluate the relative effects of nitrogen application rate, tile‐drain spacing, and tile‐drain depth on NO3‐N losses through tile drains for conditions that are typical of the Upper Midwestern USA. The ADAPT model, a daily time‐step continuous water table management model, was calibrated and validated for tile drainage and associated NO3‐N losses using long‐term monitoring data measured on three experimental plots of a Webster clay loam (fine‐loamy, mixed, superactive, mesic Typic Endoaquoll) under continuous corn (Zea mays L.) with conventional tillage treatment. For the calibration period, the model predicted mean monthly tile drainage and NO3‐N losses of 4.6 cm and 6.7 kg ha−1, respectively, against measured tile drainage and NO3‐N losses of 4.6 cm and 6.9 kg ha−1, respectively. For the validation period, the predicted mean monthly tile drainage and NO3‐N losses were 4.0 cm and 6.1 kg ha−1, respectively, against measured tile drainage and NO3‐N losses of 3.7 cm and 6.5 kg ha−1, respectively. Long‐term simulations were made for a wide range of climatic conditions between 1915 and 1996 to evaluate the effect of drain spacing, drain depth, and N application rates on tile drainage and NO3‐N losses. Simulation results indicate that much greater reductions in NO3‐N losses occur with reduced N application rates than with increases in drain spacing or decreases in drain depth.
Recovery of Giardia and Cryptosporidium from Water by Various Concentration, Elution, and Purification Techniques
Authors: Hsu Bing‐Mu , Huang Chihpin 
Published: July 2010

AbstractThe performances of different concentration and elution techniques, as well as two purification methods, were evaluated in terms of their recovery efficiencies of Giardia cysts and Cryptosporidium oocysts from seeded deionized water, treated water, and raw water samples. Out of the three concentration techniques, the Envirochek capsule filtration followed by the membrane filtration consistently gave the highest recovery efficiencies for both protozoan parasites. Although the cartridge filtration is the most suitable technique for handling large quantities of water, it also brought the greatest loss of protozoan parasites. For elution and centrifugation, both the membrane filter with hand‐kneading and Envirochek capsule with wrist‐action shaking attained higher recovery efficiencies for cysts and oocysts, Immunomagnetic separation (IMS), the purification procedure in Method 1623, had a much higher recovery efficiency for both Giardia and Cryptosporidium than the Percoll‐sucrose density gradient purification, which was the flotation procedure of the Information Collection Requirements Rule (ICR) protozoan method. Recovery efficiencies of IMS were 78.6% (SD = 13.7%) and 69.3% (SD = 13.3%) for cysts and oocysts, respectively, in contrast to the 22.7% (SD = 14.5%) for cysts and 29.9% (SD = 20.3%) for oocysts by using Percoll‐sucrose density gradient purification. In general, Giardia cysts attained a higher recovery efficiency. The recovery efficiencies of Method 1623, due to the use of Envirochek capsule filtration combined with the IMS, were 48.0% and 37.2% higher for Giardia and Cryptosporidium, respectively, than the ICR protozoan method for the three types of water.
Effects of Soil Amendments on the Bioavailability of Lead, Zinc, and Cadmium to Earthworms
Authors: Pearson Mark S. , Maenpaa Kimmo , Pierzynski Gary M. , Lydy Michael J. 
Published: July 2010

AbstractThis research investigated the effectiveness of phosphorus (P) and organic matter (OM) as possible in situ remediation techniques for metal contaminated soils. The study was designed to determine the bioavailability of Pb, Zn, and Cd individually and in combination to the earthworm Eisenia fetida in an artificial soil amended with varying levels of P and OM. A toxicokinetic approach using bioaccumulation factors and uptake rate coefficients was used to assess the bioavailability of the heavy metals. Overall, earthworms in P‐amended soils showed significantly reduced Pb levels in the individual and mixture experiments, while Zn and Cd bioavailability was not reduced. X‐ray diffraction analyses indicated that pyromorphites were formed with P amendment, thereby reducing the solubility and bioavailability of Pb within the soil. In contrast, the OM soil amendments increased bioavailability of Pb in the individual experiment and decreased it in the mixture experiment. The results of this study suggest that P amendments may be a viable technique to remediate Pb contaminated residential soils and that earthworm bioassays represent a biologically relevant measure of metal availability in soil.
Mobility of Soil Nitrogen and Microbial Responses following the Sudden Death of Established Turf
Authors: Jiang Zhongchun , Bushoven John T. , Ford Heather J. , Sawyer Carl D. , Amador José A. , Hull Richard J. 
Published: July 2010

AbstractThe stability of nitrogen within a turf‐soil ecosystem is important both for efficient turf management and preventing the contamination of ground water by nitrate. The objective of this study was to quantify responses of the microbial community and the mobility of soil nitrogen following the sudden death of established turf. Twelve‐year‐old turf plots comprising four cool‐season turfgrass species fertilized with five N sources were maintained on an Enfield silt loam (coarse‐silty over sandy or sandy‐skeletal, mixed, active, mesic Typic Dystrudept) at Kingston, RI. Half of the plots were killed with glyphosate in early September and any regrowth was removed mechanically. Measurements of soil physical, chemical, and microbiological properties and nitrate leaching in killed and healthy plots were compared for 12 mo. Turf death did not alter soil moisture, temperature, pH, or extractable ammonium. Nitrate levels were higher in both the root zone and at 60 cm following turf death and this difference persisted for the sampling year. Carbon mineralization and microbial biomass C were not different between soils from healthy and killed plots. Killed plots leached three times more nitrate than healthy plots but this amounted to less than 10% of total soil N present. Retention of nitrate in a turf‐soil system depends on absorption by living grass roots, although reasonable N stability is also provided by N cycling within the soil microbiota. Protecting ground water from nitrate contamination is optimized by maintaining a vigorous turfgrass cover.