bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nitrous Oxide Emissions from Fertilized Soils: Summary of Available Data
Authors: Eichner Melissa J. 
Published: July 2010

AbstractDirect measurements of fertilizer‐derived N2O emission data from 104 field experiments reported in agriculture and soil science literature that were obtained between 1979 and 1987 were summarized and used to estimate worldwide fertilizer‐derived N2O emissions. Although without statistical determination, there appears to be a trend between emissions and type and quantity of fertilizer applied; the available data does not indicate a trend between emissions and a particular soil type or agriculture system. Using the fraction of the N fertilizer evolved as N2O and fertilizer consumption estimates for five fertilizer types, 0.1 to 1.0 Tg N2O‐N (avg. 0.3; median 0.2) were estimated to be released during the “sampling period.” If these estimates are doubled to account for emissions after the sampling period and emissions from fertilizer lost in drainage water and ground‐water, the expected range would be 0.2 to 2.1 Tg N2O‐N (avg. 0.7; median 0.5) emitted into the atmosphere in 1984. The magnitude of this estimate is in agreement with recent global estimates. If 100 Tg N fertilizer are consumed worldwide in the year 2000, the global release of fertilizer‐derived emissions into the atmosphere will probably not exceed 3 Tg N2O‐N in the year 2000. It is estimated that 23 to 315 Gg N2O‐N were emitted into the atmosphere from fields of cultivated leguminous crops in 1986. Future research needs were suggested.
One‐Time Dormant Season Application of Gas Well Brine on Forest Land
Authors: DeWalle David R. , Galeone Daniel G. 
Published: July 2010

AbstractGas well brine was applied to forest land at loading rates of 1.52, 0.69, and 0.17 kg Cl m−2 of ground surface in November 1985 to test the feasibility of one‐time, dormant season brine applications on forest land. The number and species of woody and herbaceous plants on the treated plots and adjacent control plot were measured in July 1985 and July 1986. Both pan and suction lysimeters were used to follow changes in macro‐ and micropore soil water chemistry, respectively, at 70‐cm soil depths. Little mortality of overstory trees occurred in any of the treatments, but the number of understory red maple (Acer rubrum L.) and flowering dogwood (Cornus florida L.) saplings was reduced 30 to 40% on the plot receiving 1.52 kg Cl m−2. Several species of herbaceous plants were also eliminated from all treated plots; however, the majority of understory woody and herbaceous plants survived. Chloride, Ba, Pb, As, Se, and Cd were found in soil water at 70‐cm depths at concentrations exceeding Safe Drinking Water Act limits immediately after brine application. Concentrations of elements in macropore soil water declined to safe levels within 3 mo of treatment, except for Se. Micropore soil water, extracted under negative pressures, remained at or slightly above Safe Drinking Water Act limits for As, Se, Ba, and Cd 8 mo after treatment. Mobility of Pb and Cd in the soil appeared to be enhanced by complexation of these metals with Cl in the brine.
Streams in the New Jersey Pinelands Directly Reflect Changes in Atmospheric Deposition Chemistry
Authors: Morgan Mark D. 
Published: July 2010

AbstractThe major ion chemistry of precipitation and four undisturbed streams was measured in the New Jersey Pinelands (Pine Barrens) in 1970–1972 and 1984–1988. Over the interval, the sea salt corrected concentration of Ca and SO4 significantly declined in precipitation and all streams. Analytical problems prevented analysis of the change in precipitation H, but H significantly declined in all streams. The change in precipitation and stream water Mg and K was less consistent, but was generally toward lower concentrations in 1984–1988. After examining the potential contribution of analytical artifacts and changes in watershed characteristics and hydrology to these results, it was concluded that the changes in precipitation chemistry was real and resulted in direct changes in stream chemistry between 1970–1972 and 1984–1988. The direct effect of precipitation on stream water chemistry in the New Jersey Pinelands suggests that this region is an ideal locality to investigate future long‐term linkages between precipitation and surface water.
Content and Fractionation of Heavy Metals in Water Treatment Sludges
Authors: Elliott H. A. , Dempsey B. A. , Maille P. J. 
Published: July 2010

AbstractThe composition and distribution of Cd, Cu, Cr, Ni, Pb, and Zn in eight alum and FeCl3 coagulation sludges were investigated using a five‐step chemical fractionation procedure to assess potential impacts following soil incorporation. The mean total metal levels (mg kg−1 dry wt.) for these sludges were Cd (<2), Cu (234), Cr (187), Ni (102), Pb (230), and Zn (557), which are well below maximum allowable levels for land‐applied wastes. Two individual FeCl3 sludges had Ni levels slightly above maximum allowable concentrations. Mean total Cr and Ni concentrations in the FeCl3 sludges were, respectively, 5.4 and 3.1 times the corresponding alum sludge levels, reflecting elevated concentrations in the FeCl3 coagulant. The Cu, Cr, Ni, Pb, and Zn in sludges were predominantly bound within the oxide or silicate components. A small portion of the sludge Cd was in a readily exchangeable form, whereas the dilute acid extractable and organically bound fractions contained the majority of non‐residual Cd. Fractionation results suggest sludge Cd would potentially be mobile under acidic soil conditions, but the total Cd levels were very low (1–2 mg kg−1 compared with an allowable maximum of 25 mg kg−1). Although fractionation data must be interpreted cautiously, the results suggest most metals in water treatment sludges occur predominantly in weakly mobile, nonbioavailable forms.
Treatment of Chlordane‐Contaminated Water by the Activated Rotating Biological Contactor
Authors: Sabatini David A. , Smith John W. , Moore Larry W. 
Published: July 2010

AbstractThe insecticide chlordane (1,2,4,5,6,7,8,8‐octachloro‐2,3,3a,4,7,7a‐hexahydro‐4,7‐methanoindene) has been detected as a contaminant in groundwaters and surface waters. This study investigated the removal characteristics of chlordane using the activated rotating biological contactor (ARBC). Chlordane concentrations ranged from 0.1 to 4.6 mg/L with organic supplement levels of 500 and 175 mg/L of BOD5. The chlordane removal efficiencies ranged from 75 to 96% and the organic removal efficiencies (BOD5) ranged from 95 to 99%. Shock loadings of chlordane did not significantly hinder chlordane or organic removal efficiencies. Mass balances of the chlordane throughout the study showed 58 to 89% of the influent chlordane was not accounted for in the effluent, the system or waste solids. The relatively low volatility of chlordane and the low adsorption of the chlordane to the biomass indicates biological transformation as the primary removal mechanism in this study.
Sensitivity of Twenty Soybean Cultivars to Simulated Acid Rain
Authors: Banwart W. L. , Finke R. L. , Porter P. M. , Hassett J. J. 
Published: July 2010

AbstractEfforts to assess the effect of acid rain on soybean [Glycine max (L.) Merr.] have shown variable results. Simulated acid rain has been reported to cause increases, decreases, and no significant effect on yield. Although few parameters were identical among the diverse studies reported in the literature, one common difference was the choice of cultivar. In this study, 20 soybean cultivars were screened to determine their relative sensitivity to simulated acid rain. Soybean was grown in 1984, 1985, and 1986 in field plots in east central Illinois. Plots were protected from ambient rain and treated twice weekly with simulated rain of pH 5.6 (control) or pH 3.0. Early in each growing season visible leaf injury was noted for all 20 cultivars, and level of injury was significantly higher for plants receiving the more acidic treatment (pH 3.0). Average yield for the 20 cultivars was approximately the same when plants were treated with simulated rain of pH 3.0 as when plants were treated with stimulated rain of pH 5.6. Over all 3 yr, the group V cultivars Essex and Forrest yielded more grain and had more chaff dry matter, pods per hectare, and pods per plant with the more acidic pH treatment than with the control treatment. Only ‘Williams 82’ yielded significantly less with the more acidic pH treatment than with the control treatment. The results suggest soybean cultivars may respond differently to applications of highly acidified rainfall, but none of the cultivars tested were extremely sensitive to growth and yield reduction.
Temporal Solubility Trends of Aluminum and Iron Leached from Coal Spoils and Contaminated Soil Materials
Authors: Karathanasis A. D. , Thompson Y. L. , Evangelou V. P. 
Published: July 2010

AbstractColumn leaching experiments were conducted over a period of 5 mo on selected spoil, soil, and sediment samples collected from acid mine watersheds with low buffering capacity in Kentucky. Evaluation of effluent compositions over time suggested that at different stages of leaching these samples may release different levels of Al and Fe. These levels appeared to be controlled by the solubility of characteristic sequences of basic Al‐sulfate, Al‐hydroxide, and alumino‐silicate minerals, or Fe‐sulfate and Fe‐hydroxide minerals, which are sample specific. Jurbanite‐jurbanite, jurbanite‐alunite, and jurbanite‐alunite‐microcrystalline gibbsite appeared to be the dominant mineral sequences controlling the solubility of Al. Similarly, the jarosite‐amorphous Fe(OH)3 and amorphous Fe(OH)3‐goethite sequences appeared to control the solubility of Fe. Alternating water saturation and desaturation cycles appeared to cause more drastic changes in the above relationships than different flow rates simulating rain events of different intensity. The findings suggest that understanding temporal relationships among the sequence of mineral phases controlling Al and Fe solubility is essential for realistic modeling of Al and Fe release into aquifers.
Batch Leaching Studies of Rundle Oil Shale
Authors: Jones David R. 
Published: July 2010

AbstractThe leaching of Fe, Mn, Al, Zn, Cd, Pb, Ni, Cn, As, and Se from samples of raw and retorted Kerosene Creek seam oil shale and Telegraph Creek seam claystone from the Rundle oil shale deposit, Australia, was studied over the pH range 2 to 9.5. Low pH values were used to simulate the effects of possible acidification that might occur by oxidation of pyrite contained in the solids. The variation in leachate composition with pH highlighted the shortcomings of any batch test that seeks to categorize the behavior of a waste material solely on the basis of extraction at a single pH value. In this context, the results provided by the Resource Conservation and Recovery Act (RCRA) toxicity and American Society for Testing and Materials (ASTM) leach tests were compared. The RCRA test would not have identified As as being a potential problem in leachate from the retorted shale because, at pH 5, this element (in the form of arsenate) is strongly adsorbed to the shale matrix. The natural pH of a slurry of this waste is, however, greater than 9. Under these conditions, As is the trace element present in the highest concentrations in the leachate.
Modeling Linked Watershed and Lake Processes for Water Quality Management Decisions
Authors: Summer R. M. , Alonso C. V. , Young R. A. 
Published: July 2010

AbstractA physically based modeling approach is used to link watershed with lake processes and to simulate their responses to land management and weather conditions. Components of the watershed model, AGNPS (agricultural nonpoint‐source model), are hydrology, erosion, sediment transport, transport of nitrogen and phosphorus, and chemical oxygen demand. Using a cellular structure, runoff, sediment, and chemical variables from the watershed provide input to a lake model. This one‐dimensional model of water bodies simulates temperature stratification, mixing by wind, sedimentation, inflow density current, and algal growth. Unsteady advection‐diffusion equations characterize the dynamics of suspended sediment, soluble and sediment‐attached N and P, and chlorophyll. This model, AGNPS‐LAKE, is driven by random generation of weather conditions on a daily basis. Resulting impacts of alternative management plans are simulated by changing agricultural practices and land use, thereby modifying inflow characteristics to a lake. Modeling capabilities are being tested on eutrophic lakes in Minnesota for the purpose of simulating long‐term trends and impacts of best management practices.
Nitrate Leaching from Systematically Tiled Potato Fields in New Brunswick, Canada
Authors: Milburn P. , Richards J. E. , Gartley C. , Pollock T. , O'Neill H. , Bailey H. 
Published: July 2010

AbstractFlow volumes and NO3‐N concentrations of drain discharge from five systematically tiled, commercial potato (Solatium tuberosum L.) fields were measured from April to December, 1987 and 1988, to assess the potential for NO3‐N leaching associated with current production practices. The sites, located in New Brunswick, Canada, ranged from 3 to 10 ha and varied in fertilizer application rate, cropping practices, rainfall, and duration of data collection (the latter due to site access difficulties in the spring). Three of the five sites were representative of intense potato rotations, whereas the remaining two were representative of land conversions into potato production from more passive, low input production systems. Ten site‐years of data were collected. Drain outflow volumes averaged 75 and 115 mm per unit area in 1987 and 1988, respectively. Considerable drain flow occurred during snowmelt each year before data collection began. Measured NO3‐N concentrations ranged from 1 to 65 mg L−1 and there were substantial changes in NO3‐N concentrations within flow events. The flow‐weighted average annual nitrate concentrations of the drainage effluent, , were ≥ 10 mg L−1 for potato site‐years, regardless of whether the sites were established potato rotation fields or not. The concentrations of the established potato rotation sites also remained > 10 mg L−1 for the first non‐potato year following potato. The concentration of one potato rotation site was more than double that of the other two potato rotation sites. Incubation studies showed the soil at this site had considerably more potential to mineralize N than the other two sites. Total NO3‐N leaching for the potato site‐years for the measured April to December periods ranged from 5 to 33 kg N ha−1. More work, under controlled conditions, is required to determine both dormant and growing season NO3‐N leaching associated with various potato production systems.
Aluminum‐ and Calcium‐Binding Affinities of Some Organic Ligands in Acidic Conditions
Authors: Tam Shuk‐Ching , McColl John G. 
Published: July 2010

AbstractThe Al‐ and Ca‐binding affinities of organic ligands containing carboxylic and/or phenolic groups were studied at pH 4.5, using an ion‐pairing chromatographic technique. The ligands were loaded individually in an anion exchange column and were eluted with a solution containing the pairing ion (Al or Ca). Retention data thus obtained were normalized using data from a NaCl elution (i.e., without the pairing ion) and were used as a measure of binding affinity. At pH 4.5, the Al‐binding affinity of the following combinations of α, β‐ substituent groups was found to decrease in the order: . The Ca‐binding affinity, on the other hand, showed a different order: . The binding of Al to ligands containing the important group combinations is responsible for the more effective Al mobilization in the environment, the extent of Al availability in biological systems and the interference of Al on Fe and Ca.
Aerobic and Anaerobic Degradation of Alachlor in Samples from a Surface‐to‐Groundwater Profile
Authors: Pothuluri J. V. , Moorman T. B. , Obenhuber D. C. , Wauchope R. D. 
Published: July 2010

AbstractEstimates of pesticide degradation rates in subsoils are needed to improve models predicting pesticide movement to groundwater. Biodegradation rates of the herbicide alachlor [2‐chloro‐(2,6‐diethylphenyl)‐N‐(methoxymethyl)acetamide] in surface soil, vadose zone, and aquifer samples collected from a single site near Plains, GA were determined in the laboratory under aerobic and anaerobic conditions. Degradation was described by first‐order kinetics during 126 d of incubation. Under aerobic conditions the halflife (t1/2) of alachlor in the surface soil (t1/2 = 23 d) was less than in the vadose zone (t1/2 = 73 to 285 d) and aquifer samples (t1/2 = 320 to 324 d). Alachlor in anaerobic samples degraded less rapidly in the surface (0 to 0.6 m) and the next deepest (0.6 to 2.4 m) subsoil than under aerobic conditions (t1/2 = 100 and 144 d, respectively). Degradation in anaerobic aquifer samples was very slow (t1/2 = 337 to 553 d). Addition of organic nutrients enhanced aerobic degradation in subsurface soils and one aquifer sample, indicating that nutrient availability limits biodegradation. Total aerobic microbial populations ranged from 6.6 × 103 to 2.5 × 106 cells per gram of soil in the subsoils and aquifer samples, but were not correlated with aerobic or anaerobic degradation rates. The lower degradation rates in vadose zone and aquifer materials may be due to less microbial activity or the absence of alachlor degraders.
Atrazine and Bromide Movement through a Silt Loam Soil
Authors: Starr J. L. , Glotfelty D. E. 
Published: July 2010

AbstractThe movement of agrochemicals through soil to groundwater is affected by soil properties, soil management, timing of leaching events, and kinetics of the transformation processes. This study was conducted to determine the pattern(s) of movement of Br and atrazine (2‐chloro‐4‐ethylamino‐6‐isopropylamino‐1,3,5‐triazine) through a field soil as affected by plow‐ and conservation‐till corn (Zea mays L.), under severe leaching conditions. The soil surface inside double‐ring infiltrometers was sprayed with chemicals, 1 wk later 10 cm of solution was applied under ponded flow conditions, and soll cores removed the next day for chemical analysis. The distribution patterns of Br and atrazine with soil depth were quite similar, with the largest proportion of the chemicals observed in the surface horizon, yet all cores showed some movement of chemicals to the deepest sampling depth (90 cm). However, on average <50% of the applied water, Br, and atrazine could be found. Two quite different processes seem to be involved in the movement of these chemicals through this soil: one‐dimensional movement through the soil matrix and rapid downward movement through macropores—bypassing most of the soil matrix. These and other findings have major implications regarding the potential for contamination of groundwater by agrochemicals.
Behavior of Toluene Added to Sludge‐Amended Soils
Authors: Jin Y. , O'Connor G. A. 
Published: July 2010

AbstractToluene is a priority pollutant that can be introduced to soils in a variety of wastes, including some municipal sludges. Laboratory experiments were conducted to study the behavior of toluene in two soils in the presence and absence of municipal sludge. Sludge additions increased toluene adsorption in two soils because of increased organic C content. The source of organic C (soil or sludge) and soil clay content also influenced toluene adsorption. Toluene adsorption‐desorption was reversible in one soil, but slightly hysteretic in the other soil. An air‐flow incubation system was used to evaluate toluene volatilization and degradation. The primary fate of surface‐applied toluene in both soils was volatilization. Toluene volatilization rates were independent of sludge treatments. Toluene degradation was negligible in all treatments because of rapid volatilization losses. Despite increased toluene adsorption in the presence of sludge and reduced volatilization in saturated soils, gaseous transfer dominated all soils and treatments so that no toluene remained after 10 d.
Precipitation Nutrient Inputs in Semiarid Environments
Authors: Emmerich William E. 
Published: July 2010

AbstractSeasonal and spatial variations in precipitation nutrient inputs were suggested by differences in storm type and air mass origin into southeastern Arizona. Wet precipitation NO3‐N, NH4‐N, PO4‐P, and K inputs were collected at seven sites to determine seasonal and spatial variations in nutrient inputs. Total nutrient inputs and concentrations in summer precipitation were significantly greater than in winter precipitation. Higher summer total inputs and concentrations were attributed to storm type and air mass origin rather than precipitation amount, as summer precipitation accounted for 56% of the precipitation and 79, 69, 66, and 73% of the NO3‐N, NH4‐N, PO4‐P, and K, respectively. Spatial variability in nutrient inputs was limited to specific nutrients, seasons, and sites and attributed to precipitation variability and localized sources. Generally, the air masses and storm types that produced seasonal differences in nutrient inputs and concentrations affected all sites uniformly.
Biodegradation of Land‐Applied Sludge
Authors: Boyle Michael 
Published: July 2010

AbstractThe economic and environmental costs of sludge disposal are escalating rapidly. There is a need to increase the rate of decomposition during and after sludge formation. Sludge formation often determines which environmental factors and enzymatic reactions are effective in further degrading this complex substrate. From activated waste treatment through anaerobic digestion to land application, there is a decrease in the volume but an increase in the stabilization of the remaining organic material. Before we can design better methods for land disposal or “engineer” better microbial decomposers, the limitations of sludge decay must first be addressed.
Nature of Dissolved Organic Matter in the Drainage Basin of a Boreal Humic River in Northern Finland
Authors: Heikkinen Kaisa 
Published: July 2010

AbstractThe nature of dissolved organic matter in river, brook, and peat mining water in the drainage basin of the humic Kiiminkijoki River, located in an area of minerotrophic peatlands in northern Finland in the boreal region, was studied by gel filtration. Special emphasis was paid to changes in the nature of high molecular weight organic Fe‐P colloids that result from peat mining. The river water is organically colored, with high organic matter and Fe concentrations. High apparent molecular weight (HAMW) organic colloids are important for the transport of Fe and P in the basin. The gel filtration data suggest that the DOM in the water consist mainly of fulvic acids (FA), although humic acids (HA) are also important. The proportion of dissolved organic C (DOC) and Fe in the HAMW organic colloids increases with increasing DOC and iron concentrations in the river water. The apparent molecular weight of the DOM is higher than in the lakes in the area of ombrotrophic peatlands in southern Finland. Color in this humic water increases with DOC and Fe concentrations. The effect of Fe on color values can be seen in filtered (<1.2 µm) river water and in all the gel filtration fractions. The results indicate an increase in the mobilization of HAMW organic Fe‐P colloids in the peatlands of the area following drainage and peat mining. The average ratio of Fe to DOC in the HAMW organic fraction is higher in the peat mining water than in the Keihäsoja brook in a natural peaty urea. It is possible that the Fe to DOC ratio in these colloids transported in the river increases following drainage and peat mining, especially under low flow conditions in summer. This may lead to gradual changes in the detritus food webs of the river ecosystem.