bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sources and Transformations of Nitrogen Compounds along the Lower Jordan River
Authors: Segal‐Rozenhaimer Michal , Shavit Uri , Vengosh Avner , Gavrieli Ittai , Farber Efrat , Holtzman Ran , Mayer Bernhard , Shaviv Avi 
Published: June 2010

ABSTRACTThe Lower Jordan River is located in the semiarid area of the Jordan Valley, along the border between Israel and Jordan. The implementation of the water sections of the peace treaty between Israel and Jordan and the countries' commitment to improve the ecological sustainability of the river system require a better understanding of the riverine environment. This paper investigates the sources and transformations of nitrogen compounds in the Lower Jordan River by applying a combination of physical, chemical, isotopic, and mathematical techniques. The source waters of the Lower Jordan River contain sewage, which contributes high ammonium loads to the river. Ammonium concentrations decrease from 20 to 0–5 mg N L−1along the first 20 km of the Lower Jordan River, while nitrate concentrations increase from nearly zero to 10–15 mg N L−1, and δ15N (NO3) values increase from less than 5‰ to 15–20‰. Our data analysis indicates that intensive nitrification occurs along the river, between 5 and 12 km from the Sea of Galilee, while further downstream nitrate concentration increases mostly due to an external subsurface water source that enters the river.
Nutrient Input and Removal Trends for Agricultural Soils in Nine Geographic Regions in Arkansas
Authors: Slaton Nathan A. , Brye Kristofor R. , Daniels Mike B. , Daniel Tommy C. , Norman Richard J. , Miller David M. 
Published: June 2010

ABSTRACTKnowledge of the balance between nutrient inputs and removals is required for identifying regions that possess an excess or deficit of nutrients. This assessment describes the balance between the agricultural nutrient inputs and removals for nine geographical districts within Arkansas from 1997 to 2001. The total N, P, and K inputs were summed for each district and included inorganic fertilizer and collectable nutrients excreted as poultry, turkey, dairy, and hog manures. Nutrients removed by harvested crops were summed and subtracted from total nutrient inputs to calculate the net nutrient balance. The net balances for N, P, and K were distributed across the hectarage used for row crop, hay, pasture, or combinations of these land uses. Row‐crop agriculture predominates in the eastern one‐third and animal agriculture predominates in the western two‐thirds of Arkansas. Nutrients derived from poultry litter accounted for >92% of the total transportable manure N, P, and K. The three districts in the eastern one‐third of Arkansas contained 95% of the row‐crop hectarage and had net N and P balances that were near zero or negative. The six districts in the western two‐thirds of Arkansas accounted for 89 to 100% of the animal populations, had positive net balances for N and P, and excess P ranged from 1 to 9 kg P ha−1 when distributed across row‐crop, hay, and pasture hectarage. Transport of excess nutrients, primarily in poultry litter, outside of the districts in western Arkansas is needed to achieve a balance between soil inputs and removals of P and N.
Phosphorus in Surface Runoff from Calcareous Arable Soils of the Semiarid Western United States
Authors: Turner Benjamin L. , Kay Mary A. , Westermann Dale T. 
Published: June 2010

ABSTRACTManagement strategies that minimize P transfer from agricultural land to water bodies are based on relationships between P concentrations in soil and runoff. This study evaluated such relationships for surface runoff generated by simulated sprinkler irrigation onto calcareous arable soils of the semiarid western United States. Irrigation was applied at 70 mm h−1to plots on four soils containing a wide range of extractable P concentrations. Two irrigation events were conducted on each plot, first onto dry soil and then after 24 h onto wet soil. Particulate P (>0.45 μm) was the dominant fraction in surface runoff from all soils and was strongly correlated with suspended sediment concentration. For individual soil types, filterable reactive P (<0.45 μm) concentrations were strongly correlated with all soil‐test P methods, including environmental tests involving extraction with water (1:10 and 1:200 soil to solution ratio), 0.01MCaCl2, and iron strips. However, only the Olsen‐P agronomic soil‐test procedure gave models that were not significantly different among soils. Soil chemical differences, including lower CaCO3and water‐extractable Ca, higher water‐extractable Fe, and higher pH, appeared to account for differences in filterable reactive P concentrations in runoff from soils with similar extractable P concentrations. It may therefore be possible to use a single agronomic test to predict filterable reactive P concentrations in surface runoff from calcareous soils, but inherent dangers exist in assuming a consistent response, even for one soil within a single field.
Effect of Poultry Diet on Phosphorus in Runoff from Soils Amended with Poultry Manure and Compost
Authors: Vadas P. A. , Meisinger J. J. , Sikora L. J. , McMurtry J. P. , Sefton A. E. 
Published: June 2010

ABSTRACTPhosphorus in runoff from fields where poultry litter is surface‐applied is an environmental concern. We investigated the effect of adding phytase and reducing supplemental P in poultry diets and composting poultry manures, with and without Fe and Al amendments, on P in manures, composts, and runoff. We used four diets: normal (no phytase) with 0.4% supplemental P, normal + phytase, phytase + 0.3% P, and phytase + 0.2% P. Adding phytase and decreasing supplemental P in diets reduced total P but increased water‐extractable P in manure. Compared with manures, composting reduced both total P, due to dilution of manure with woodchips and straw, and water‐extractable P, but beyond a dilution effect so that the ratio of water‐extractable P to total P was less in compost than manure. Adding Fe and Al during composting did not consistently change total P or water‐extractable P. Manures and composts were surface‐applied to soil boxes at a rate of 50 kg total P ha−1 and subjected to simulated rainfall, with runoff collected for 30 min. For manures, phytase and decreased P in diets had no significant effect on total P or molybdate‐reactive P loads (kg ha−1) in runoff. Composting reduced total P and molybdate‐reactive P loads in runoff, and adding Fe and Al to compost reduced total P but not molybdate‐reactive P loads in runoff. Molybdate‐reactive P in runoff (mg box−1) was well correlated to water‐extractable P applied to boxes (mg box−1) in manures and composts. Therefore, the final environmental impact of dietary phytase will depend on the management of poultry diets, manure, and farm‐scale P balances.
Nitrogen, Phosphorus, and Potassium Uptake by Wheat and Their Distribution in Soil following Successive, Annual Compost Applications
Authors: Bar‐Tal A. , Yermiyahu U. , Beraud J. , Keinan M. , Rosenberg R. , Zohar D. , Rosen V. , Fine P. 
Published: June 2010

ABSTRACTThe overall objective of the present study was to determine the loading limits of composts that should be applied annually to irrigated wheat. We conducted a container experiment in a greenhouse during four years. It included eight treatments: sewage sludge compost (SSC) and cattle manure compost (CMC), each applied annually to a sandy soil, at rates equivalent to 3, 6, and 12 kg m−2, and two controls, one fertilized and one unfertilized. Total dry matter (DM), grain production, and the amount of N, P, and K taken up by plants increased with increasing compost rate. Nitrogen uptake by the plants of the fertilized control was much higher than by the plants of the highest compost rate. Phosphorus and K uptake by the plants amended with the highest compost rate was much higher than by the fertilized control plants. Inorganic N quantity in the soil increased with increasing compost rate and with successive applications. The net N mineralization during the first year of wheat growth was very low, less than 3.5% of the applied organic N under all compost application rates. The contribution of the organic N mineralization increased during the second and third years. Most of the N increase in the compost treatment was found in the upper layer of 0 to 15 cm, whereas in the fertilized treatment N accumulated from the surface to the bottom of the container, 0 to 55 cm. The successive application of high rates of composts resulted in P and K accumulation in the soil profile.
Estimating Bulk Density in Vertically Exposed Stoney Alluvium Using a Modified Excavation Method
Authors: Brye K. R. , Morris T. L. , Miller D. M. , Formica S. J. , Van Eps M. A. 
Published: June 2010

ABSTRACTDespite many decades of education and refining land‐use practices, accelerated stream bank erosion is still prevalent in the United States. Eroding stream banks produce a sediment load to the riverine system and can cause reduced water quality as a result of increased suspended sediment. As total maximum daily loads (TMDLs) for water bodies impaired by turbidity or suspended sediments become more numerous, a simple, in situ field technique will be needed to estimate the bulk density of readily erodible stream bank material so that reasonably accurate sediment loading rates can be estimated. In this study, the excavation/polyurethane‐foam technique for estimating total bulk density was applied to vertically exposed alluvium with high coarse‐fragment content. Though not previously attempted in vertically exposed alluvium with high coarse‐fragment content, the excavation/polyurethane‐foam technique appears to provide a reasonably accurate estimate of the total and soil (<2‐mm size fraction) bulk density from vertically exposed, alluvial deposits with high coarse‐fragment content (i.e., >70%) along eroding stream banks. Obtaining bulk density estimates using this method would facilitate calculation of sediment loading rates to riverine systems with actual field data.
Adsorption of Trace Metals on Glass Fiber Filters
Authors: Fuhrmann Mark , Fitts Jeffrey P. 
Published: June 2010

ABSTRACTFilters, containing glass‐fiber (GF) filter material, are commonly used as the primary filter or as the prefilter in sampling natural waters and laboratory experiments with high concentrations of suspended solids. We observed that GF filter material removed substantial quantities of trace metals from solutions of low ionic strength at near neutral and slightly acidic pH. The GF material sorbed essentially all Pb and Ag from 5‐mL aliquots of solutions containing 0.054 and 0.093 mM, respectively. Somewhat less Ni was sorbed from a 0.099 mM solution. This material retained about 43 μmol of Ag per gram of GF material (4600 μg/g). The Ag and Ni sorption was highest at low KNO3 concentrations (as background electrolyte) and decreased to a constant concentration of sorbed metal at approximately 10 mM KNO3 Glass‐fiber filter material should only be used with careful testing for the elements of concern under conditions that closely match expected environmental or experimental conditions.
An Economic Evaluation of Livestock Odor Regulation Distances
Authors: Bazen Ernest F. , Fleming Ronald A. 
Published: June 2010

ABSTRACTSetback regulations—legislated distances that livestock production facilities must be removed from surrounding properties—are meant to mitigate odor impacts. If the setback length is too short, then there is evidence that surrounding properties and people suffer uncompensated damages. If, on the other hand, setback lengths are too long, then livestock producers may be paying more than that required to compensate for odor‐related environmental damages. The purpose of this study is to assess the impact of Kentucky's livestock production facility setbacks on the value of surrounding properties and farm financial management decisions. This paper develops a model of the benefits of livestock odor reduction and the livestock odor abatement cost associated with setback lengths paid by producers. The results of this investigation indicate that the mandated setback lengths for Kentucky are too short. Livestock production firms are worse off under longer setback lengths, but the losses to surrounding home owners far exceed the firm gains at the mandated setbacks. A finding of this study is that the firm has no incentive to completely protect the legislated setback length. Livestock producers in compliance with the relevant setback length may feel protected from odor lawsuits despite damage being done to surrounding property. This suggests that the perceived threat of lawsuit is currently low in the state of Kentucky. Both industry and public goals could be met from further research including location and economic impact of livestock production.
Monitoring Nitrogen Deposition in Throughfall Using Ion Exchange Resin Columns: A Field Test in the San Bernardino Mountains
Authors: Fenn Mark E. , Poth Mark A. 
Published: June 2010

ABSTRACTConventional throughfall collection methods are labor intensive and analytically expensive to implement at broad scales. This study was conducted to test an alternative approach requiring infrequent sample collection and a greatly reduced number of chemical analyses. The major objective of the study was to determine the feasibility of using ion exchange resin (IER) to measure N deposition in throughfall with field deployment periods of 3 to 12 mo. Nitrogen deposition measurements in bulk throughfall collected under pine (Pinus sp.) canopies and in forest clearings were compared between co‐located conventional throughfall solution collectors and IER throughfall collectors using mixed bed IER columns. Deposition data were collected for 1 yr at a high deposition site (Camp Paivika, CP) and a relatively low one (Barton Flats, BF) in the San Bernardino Mountains in southern California: Annual throughfall deposition values (kg ha−1 of NH4–N + NO3–N) under large ponderosa pine trees (Pinus ponderosa Laws.) were 145.8 and 143.9 at CP and 17.0 and 15.0 at BF according to the IER and conventional methods, respectively. Analogous values for bulk deposition in forest clearings were 15.6 and 12.3 at CP and 4.0 and 3.3 at BF. It was concluded that the IER collectors can be used for routine monitoring of deposition in throughfall and bulk deposition, provided that field blanks are used to account for background levels of N in the IER columns, which at times are slightly elevated, possibly from slow release of amine groups from the anion exchange resin during field exposures.
Biological Reduction of Chlorate in a Gas‐Lift Reactor Using Hydrogen as an Energy Source
Authors: Kroon A. G. M. , van Ginkel C. G. 
Published: June 2010

ABSTRACTChlorate release into the environment occurs with its manufacture and use. Biological reduction of chlorate offers an attractive option to decrease this release. A hydrogen gas‐lift reactor with microorganisms attached to pumice particles was used for the treatment of wastewater containing high concentrations of chlorate. The microorganisms used chlorate as an electron acceptor and hydrogen gas as a reducing agent. After a start‐up period of only a few weeks, chlorate reduction rates of 3.2 mmol L−1 h−1 were achieved during continuous operation. During this period, a hydrogen consumption rate of 14.5 mmol L−1 h−1 was observed. Complete removal of chlorate was maintained at hydraulic retention times of 6 h. This study clearly demonstrates the potential of hydrogen gas‐lift bioreactors for the treatment of chlorate‐containing waste streams.
Mechanisms of Thorium Migration in a Semiarid Soil
Authors: Bednar A. J. , Gent D. B. , Gilmore J. R. , Sturgis T. C. , Larson S. L. 
Published: June 2010

ABSTRACTThorium concentrations at Kirtland Air Force Base training sites in Albuquerque, NM, have been previously described; however, the mechanisms of thorium migration were not fully understood. This work describes the processes affecting thorium mobility in this semiarid soil, which has implications for future remedial action. Aqueous extraction and filtration experiments have demonstrated the colloidal nature of thorium in the soil, due in part to the low solubility of thorium oxide. Colloidal material was defined as that removed by a 0.22‐μm or smaller filter after being filtered to nominally dissolved size (0.45 μm). Additionally, association of thorium with natural organic matter is suggested by micro‐ and ultrafiltration methods, and electrokinetic data, which indicate thorium migration as a negatively charged particle or anionic complex with organic matter. Soil fractionation and digestion experiments show a bimodal distribution of thorium in the largest and smallest size fractions, most likely associated with detrital plant material and inorganic oxide particles, respectively. Plant uptake studies suggest this could also be a mode of thorium migration as plants grown in thorium‐containing soil had a higher thorium concentration than those in control soils. Soil erosion laboratory experiments with wind and surface water overflow were performed to determine bulk soil material movement as a possible mechanism of mobility. Information from these experiments is being used to determine viable soil stabilization techniques at the site to maintain a usable training facility with minimal environmental impact.
Fluometuron and Pendimethalin Runoff from Strip and Conventionally Tilled Cotton in the Southern Atlantic Coastal Plain
Authors: Potter Thomas L. , Truman Clint C. , Bosch David D. , Bednarz Craig 
Published: June 2010

ABSTRACTIn the Atlantic Coastal Plain region of southern Georgia (USA), cotton (Gossypium hirsutum L.) acreage increased threefold in the past decade. To more effectively protect water quality in the region, best management practices are needed that reduce pesticide runoff from fields in cotton production. This study compared runoff of two herbicides, fluometuron [N,N‐dimethyl‐N′‐[3‐(trifluoromethyl)‐phenyl]‐urea] and pendimethalin [N‐(1‐ethylpropyl)‐3,4‐dimethyl‐2,6‐dinitro‐benzenamine], from plots in strip‐tillage (ST) and conventional‐tillage (CT) management near Tifton, GA. Rainfall simulations were conducted one day after preemergence herbicide applications to 0.0006‐ha plots and runoff from 0.15‐ha plots due to natural rainfall following preemergence pendimethalin and fluometuron and postemergence fluometuron use was monitored. Pendimethalin runoff was greater under CT than ST due to strong pendimethalin soil sorption and higher erosion and runoff under CT. The highest losses, 1.3% of applied in CT and 0.22% of applied in ST, were observed during rainfall simulations conducted 1 DAT. Fluometuron runoff from natural rainfall was substantially lower from ST than from CT plots but the trend was reversed in rainfall simulations. In all studies, fluometuron runoff was also relatively low (<1% of applied), and on plots under natural rainfall, desmethylfluometuron (DMF) represented about 50% of total fluometuron runoff. Fluometuron's relatively low runoff rate appeared linked to its rapid leaching, and high DMF detection rates in runoff support DMF inclusion in fluometuron risk assessments. Results showed that ST has the potential to reduce runoff of both herbicides, but fluometuron leaching may be a ground water quality concern.
Evaluation of the Phosphorus Source Component in the Phosphorus Index for Pastures
Authors: DeLaune P. B. , Moore P. A. , Carman D. K. , Sharpley A. N. , Haggard B. E. , Daniel T. C. 
Published: June 2010

ABSTRACTA phosphorus (P) index for pastures was developed to write nutrient management plans that determine how much P can be applied to a given field. The objectives of this study were to (i) evaluate and compare the P index for pastures, particularly the P source component, and an environmental threshold soil test P level by conducting rainfall simulations on contrasting soils under various management scenarios; and (ii) evaluate the P index for pastures on field‐scale watersheds. Poultry litter was applied to 12 small plots on each of six farms based on either an environmental threshold soil test P level or on the P index for pastures, and P runoff was evaluated using rainfall simulators. The P index was also evaluated from two small (0.405 ha) watersheds that had been fertilized annually with poultry litter since 1995. Results from the small plot study showed that soil test P alone was a poor predictor of P concentrations in runoff water following poultry litter applications. The relationship between P in runoff and the amount of soluble P applied was highly significant. Furthermore, P concentrations in runoff from plots with and without litter applications were significantly correlated to P index values. Studies on pastures receiving natural rainfall and annual poultry litter applications indicated that the P index for pastures predicted P loss accurately without calibration (y = 1.16x − 0.23, r2 = 0.83). These data indicate that the P index for pastures can accurately assess the risk of P loss from fields receiving poultry litter applications in Arkansas and provide a more realistic risk assessment than threshold soil test P levels.
Decreasing Phosphorus Runoff Losses from Land‐Applied Poultry Litter with Dietary Modifications and Alum Addition
Authors: Smith Douglas R. , Moore P. A. , Miles D. M. , Haggard B. E. , Daniel T. C. 
Published: June 2010

ABSTRACTPhosphorus (P) losses from pastures fertilized with poultry litter contribute to the degradation of surface water quality in the United States. Dietary modification and manure amendments may reduce potential P runoff losses from pastures. In the current study, broilers were fed a normal diet, phytase diet, high available phosphorus (HAP) corn diet, or HAP corn + phytase diet. Litter treatments were untreated control and alum added at 10% by weight between flocks. Phytase and HAP corn diets reduced litter dissolved P content in poultry litter by 10 and 35%, respectively, compared with the normal diet (789 mg P kg−1). Alum treatment of poultry litter reduced the amount of dissolved P by 47%, while a 74% reduction was noted after alum treatment of litter from the HAP corn + phytase diet. The P concentrations in runoff water were highest from plots receiving poultry litter from the normal diet, whereas plots receiving poultry litter from phytase and HAP corn diets had reduced P concentrations. The addition of alum to the various poultry litters reduced P runoff by 52 to 69%; the greatest reduction occurred when alum was used in conjunction with HAP corn and phytase. This study demonstrates the potential added benefits of using dietary modification in conjunction with manure amendments in poultry operations. Integrators and producers should consider the use of phytase, HAP corn, and alum to reduce potential P losses associated with poultry litter application to pastures.