bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacteriological Quality of Surface and Subsurface Runoff from Manured Sandy Clay Loam Soil
Authors: Culley J. L. B. , Phillips P. A. 
Published: July 2010

AbstractThe bacterial quality of surface waters determines their acceptability for both drinking and recreational uses. Since livestock activities have been implicated as sources of fecal contamination, information on the bacterial quality of runoff from manured cropland is required. Bacteriological parameters (total coliform [TC], fecal coliform [FC], and fecal streptococcus [FS]) were monitored in spring surface and subsurface discharge from continuously corn‐cropped sandy clay loam that was amended with either liquid dairy manure, chemical N‐P‐K fertilizer at about recommended rates, or no fertilizer. Liquid manure was applied for 6 years at three rates, which averaged 105, 263, and 420 m3 ha−1 year−1, plowed under after harvest, in spring prior to seeding, or split between spring and fall. Liquid manure was also applied directly to snow or frozen ground.With the exception of winter‐applied treatments, neither rate nor time of manure application significantly affected organism contents in spring surface or subsurface discharge. Winter manure applications resulted in significantly higher FC and FS counts in surface runoff and FS counts in subsurface discharge when compared with other application times. Fecal coliform and FS counts did not increase with increased winter application rates. Fecal streptococcus populations of winter‐applied manure changed little during the first 100 days after application, while both TC and FC counts declined in the manure to low levels 24–40 days after spreading.
Effects of Ammonium Sulfate and Urea on the Growth of Chlorophycean Algae From Rice Fields
Authors: Barrett Michael R. , Koch Arthur R. 
Published: July 2010

AbstractAlgal growth in rice (Oryza sativa L.) fields is often abundant, but the quantitative effect of fertilization on algae is not well‐understood. The growth of four unialgal isolates from fertilized rice floodwater, including Bracteacoccus minor, Scenedesmus sp., and two species of Chlamydomonas, was studied in soil water extract enriched with an inorganic algal medium and with N as either urea (CO(NH2)2) or ammonium sulfate ((NH4)2SO4). Except for one species of Chlamydomonas, isolates had higher cell counts in urea‐enriched cultures. There was no significant difference between the growth of cultures with 25 or 50 mg/liter N as urea added or between those with 25 or 50 mg/liter N as (NH4)2SO4. The maximum biomass of all N‐enriched cultures was significantly greater than that of cultures with no N added to the medium. Differences in final biomass among isolates were significant but were not proportional to that observed at earlier stages in the growth curve.
Chalk Point: A Case Study of the Impact of Brackish Water Cooling Towers on an Agricultural Environment
Authors: Mulchi Charles L. , Armbruster James A. , Wolf D. C. 
Published: July 2010

AbstractThe construction of two brackish water, natural‐draft cooling towers (Units 3 and 4) by the Potomac Electric Power Co. at their Chalk Point Generating Station, located in a major agricultural region in southern Maryland, aroused concern that saline aerosol emissions from the facility might significantly impact the crops and soils near the facility. Permanent research and monitoring sites were established at distances of 1.6, 4.8, and 9.6 km north, east, south, and west from the cooling towers. Over the period May 1973–May 1980, baseline and postoperational information was obtained on monthly Na and Cl deposition rates; foliar chemistry and yields of corn (Zea mays L.) and soybeans (Glycine max L. (Merr.)); soil pH and extractable P, K, Ca, Mg; Na; and electrical conductivity values on 0‐ to 15‐cm depth soil samples. Unit 3 began operations in July 1975.The quantities of saline aerosol emissions from Unit 3 were insufficient to cause detectable changes in the Na and Cl deposition rates above baseline values at or beyond the 1.6‐km sites, the closest agricultural areas to the power plant. Also, no significant changes were observed in Na and Cl levels in vegetative samples collected from corn and soybeans grown in the research sites after Unit 3 began operations. Significant reductions in corn yields that were more associated with rainfall patterns than to salt emissions were observed during post‐Unit 3 operations. Significant changes that, in most cases, could be closely associated with the general increases observed in soil acidity, were observed in each of the soil chemistry parameters with time.In conclusion, saline aerosol emissions from Chalk Point Unit 3 natural draft cooling tower did not have a detectable impact on the agricultural crops and soils adjacent to the emission source.
Environmental Effects of a Medium‐Fertility 12‐Month Pasture Program: I. Hydrology and Soil Loss
Authors: Owens L. B. , Van Keuren R. W. , Edwards W. M. 
Published: July 2010

AbstractFour small, sloping upland watersheds in Ohio (0.5–1.1 ha) were studied for 5 years to investigate hydrologic and soil erosion changes resulting from a beef cattle pasturing program. The cattle grazed all four pastures rotationally during the summer (May–October) and were wintered on hay (November–April) on the same pasture each year. The long‐term record for these pastures, which had been in meadow and light pasturing during the previous years, showed average annual surface runoff to be approximately 15 mm. During the 5 years of the grazing project, the three summer‐grazing‐only pastures showed a slight increase in surface runoff and a trace of soil loss. However, the winter‐feeding/summer‐grazing area showed a large increase in surface runoff (131 mm/year) and soil loss (1,355 kg/ha per year). Eighty‐one percent of the soil loss occurred during the dormant season. Large runoff events, although a small percentage of the total number of events, produced most of the runoff volume and most of the soil loss. Water balance studies indicated that subsurface flow was relatively unchanged by the grazing program. The increase in surface runoff was offset by a decrease in the evapotranspiration.
Chemical Properties and Mineralogical Characteristics of Selected Dredged Material
Authors: Combs S. M. , Dowdy R. H. , Gupta S. C. , Larson W. E. , Gast R. G. 
Published: July 2010

AbstractTransporting dredged spoils inland for use in reconditioning adjacent lands marginally suited for agricultural production may be an attractive alternative to other disposal practices. The objective of this study was to evaluate dredged materials (DM) by determining the elemental content and mineralogical characteristics of 10 freshwater and estuarine DM from eastern and central U.S. waterways.Dredged materials ranged from very acidic (pH ≤ 4.7) to alkaline (pH ≥ 7.4) in reaction. Acidity was attributed to S2− and/or Fe2+ oxidation resulting when initially reduced sediments were exposed to aerobic conditions. Dredged materials had cation exchange capacity values that ranged from 1.0 to 33.5 meq/100 g. Organic matter contents (5.9–22.5%) accounted for approximately 60% of the variation in the exchange capacity of fine‐textured DM. Total N was mainly in organic forms and C/N ratios ranged from 13:1 to 22:1.Dredged materials exhibited variable accumulations of nutrients and metals reflecting varying degrees of waterway contamination. The levels of Al, Ca, K, Mg, P, and S were generally higher in DM than in reference Minnesota soils. Cadmium, Cr, Ni, Pb, and Zn concentrations in DM were 2 to 6 times, and Cu 20 times, those observed in the reference soils. Manganese concentrations were substantially less in DM than in the soils.Mineralogy varied with geographical location, contributing watershed, and environmental conditions. All DM contained kaolinite and illite. Amounts of montmorillonite varied because of some conversion to pedogenic chlorite during rapid leaching conditions of sediment drainage. Crystalline Fe2O3 was associated with DM clay fractions, indicating precipitation of colloidal‐sized hydrous oxide particles and/or surface coatings on clay complexes.
Monitoring of a Municipal Sludge Entrenchment Site
Authors: Sikora L. J. , Burge W. D. , Jones J. E. 
Published: July 2010

AbstractRaw, highly limed, filter‐cake sludge (22% solid) was entrenched 18 ha of well‐drained, silt loam soil of the Manor (Typic Dystrochrept) and Glenelg (Typic Hapludalf) soil series in 1975 at a rate 2,200 wet metric tons/ha. As part of the overall evaluation of the environmental effects of sludge entrenchment, the USDA‐ARS, in cooperation with the Maryland Environmental Service, began to monitor the site in 1977 to determine the mineralization and movement of N, movement of heavy metals, and die‐off rate and movement of salmonellae, ascaris ova, and fecal indicators in the entrenched sludge and soil profile. Total N, NH4‐N, and Cl levels decreased in the entrenched sludge with time, and leached through the soil profile past the lowest sampling point, which was 100 cm below the trench bottom. Nitrate‐N was formed and migrated to the deepest sampling point, and direct evidence that denitrification occurred was lacking. Heavy metal losses from the entrenched sludge were negligible probably because the pH of the sludge after 45 months was above 7.0. A predictive equation based on decreases in sludge total N was developed for use as a tool for determining the age when the entrenched sludge was stablized. Fecal coliform concentrations were very low. Ascaris ova were not detected in the sludge prior to entrenchment or in samples taken during the monitoring period which, in part, may have been due to analytical limitations. Pathogen hazard associated with the entrenched, limed sludge appeared to be minimal. The major environmental effect of sludge entrenchment is possible contamination of ground water by N leached from the sludge.
An Analysis of Short‐ and Long‐Term Impacts of Several Soil‐Loss Control Measures
Authors: English Burton C. , Heady Earl O. 
Published: July 2010

AbstractTwo large‐scale interregional and national linear‐programming models are used to examine the impacts on agricultural production, resource use, and soil loss of several soil‐loss control measures. The short‐run model (1985) incorporates no productivity loss due to soil erosion, while the long‐run model (2000) does. Five short‐run and six long‐run alternatives are analyzed. These alternatives include reducing soil losses by fixed percentage values or to a fixed multiple of the soil‐loss tolerance levels (2T in the short‐run and T in the long‐run model).The base solutions with no targeted soil‐loss reductions project gross soil losses of 2.8 and 1.1 billion t for 1985 and 2000, respectively. By limiting soil losses to 2T and T, the soil losses are reduced to 1.4 and 0.6 million t, respectively.Many more hectares are placed in conservation practices and reduced‐tillage methods in the long‐run when compared with the short‐run model. Soil‐conserving practices such as contours, strip cropping, and terracing are not used in the short run, indicating that conservation practices will not be utilized under a short planning horizon and an objective of profit maximization. The private economic benefits for conserving soil in the short run are less than the costs in doing so. When yield impacts from soil erosion are considered as in the long‐term solution, it is profitable to use these conservation practices.
Residues of 4‐(2,4‐Dichlorophenoxy)butyric Acid in Winter Wheat
Authors: Leather G. R. , Forrence L. E. 
Published: July 2010

AbstractResidue data were collected during a 1‐year field investigation to support a label amendment for the use of 2,4‐DB (4‐[2,4‐dichlorophenoxy]butyric acid) in small grains. The 2,4‐DB was applied to ‘blue boy’ winter wheat (Triticum aestivum L.) at the “recommended” and “twice the recommended” rates as the dimethylamine salt (1.68 and 3.36 kg ai [active ingredient]/ha) and the isooctyl ester (1.12 and 2.24 kg ai/ha). Low levels of 2,4‐DB residues (4.9–7.4 ppmw) were found in wheat straw harvested 70 d after spraying with the isooctyl ester formulation, but no 2,4‐DB residues were found in wheat straw treated with the dimethylamine form. The grain did not contain detectable levels of 2,4‐DB or 2,4‐D [(2,4‐dichlorophenoxy] acetic acid) residues from any 2,4‐DB treatment. No difference in yield between the control and 2,4‐DB‐treated plots was obtained. Rainfall that occurred 4 h after application may have resulted in some loss of the herbicide and the data presented should be considered preliminary.
Radionuclide Concentrations in Vegetation at a Solid Radioactive Waste‐Disposal Area in Southeastern Idaho
Authors: Arthur W. J. 
Published: July 2010

AbstractConcentrations of 238Pu, 239,240Pu, and 241Am in crested wheatgrass (Agropyron cristatum (L.) Gaertn) and Russian thistle (Salsola kali L.) samples collected at a solid radioactive waste‐disposal area in southeastern Idaho were significantly (P ± 0.05) greater than concentrations in control vegetation. No significant differences were found for 90Sr or 137Cs concentrations between the waste‐disposal and control‐area vegetation. Russian thistle had more radionuclide contamination than crested wheatgrass, presumably because of its greater rooting depth and spreading growth. The total radionuclide inventory of 90Sr, 137Cs, 238Pu, 239,240Pu, and 241Am in vegetation at the 36‐ha waste‐disposal area (77 µCi) was not significantly (P > 0.05) greater than the 17 µCi in control‐area vegetation. Ninety percent of the radioactivity in waste‐disposal area vegetation and 99% in control‐area vegetation were attributed to 90Sr and 137Cs. The Pu inventory in Subsurface Disposal Area (SDA) vegetation was only 0.02% of the quantity of Pu estimated to occur in SDA surface soils in 1974. Accumulation of radionuclides by vegetation is not considered a major mode of radionuclide transport through the environment surrounding this radioactive‐waste‐disposal area.
A Comparison of Cadmium and Zinc Accumulation by Four Cultivars of Barley Grown in Sludge‐Amended Soils
Authors: Chang A. C. , Page A. L. , Foster K. W. , Jones T. E. 
Published: July 2010

AbstractA greenhouse experiment was conducted to compare the plant‐tissue accumulation of Cd and Zn by four cultivars of barley (Hordeum vulgare L.) grown on three soils amended with 20 and 100 t/ha dried Imhoff tank sludges. Results indicated that metal uptakes by four cultivars of barley (Barsoy, Briggs, Florida 103, and Larker) were not significantly different when they were grown on both sludge‐treated and non‐sludge‐treated (control) soils. The Cd and Zn concentrations of the plant tissue from sludge‐treated soils, however, were significantly influenced by the sludge application and the soil type. For four cultivars of barley grown on the Ramona sandy loam soil, the Cd content of grain averaged < 0.04 (< 0.04–0.03) µg/g at the control and increased to 0.38 (0.19–0.53) µg/g at the 100‐t/ha sludge treatment. Under the sameconditions, the average Zn concentrations of barley grain were 41, 67, and 92 µg/g for the control, 20‐t/ha, and 100‐t/ha treatments, respectively. Both soil texture and pH influenced Cd and Zn contents of barley. Crops grown on the Domino loam soil (fine, mixed, thermic Xerollic Calciorthid) accumulated the least amounts of Cd and Zn. At heavy sludge applications, higher levels of plant‐tissue Cd and Zn were often found in barley grown on soils of coarser texture (Ramona sandy loam [fine, mixed, thermic Typic Haploxeralf] and Greenfield sandy loam [coarse, mixed, thermic Typic Haploxeralf]) and lower pH (Ramona sandy loam, pH = 6.0).
Concentrations of Six Trace Metals in Some Major Minnesota Soil Series
Authors: Pierce F. J. , Dowdy R. H. , Grigal D. F. 
Published: July 2010

AbstractConcentrations of Cd, Cr, Cu, Ni, Pb, and Zn were determined in 16 soil series in Minnesota to establish baseline levels of these trace metals. These soils are representative of those formed on seven major parent materials in the state and comprise a broad range of soil properties. Extracts with 0.1M K4P2O7·3H2O, 1.0NW HNO3, and a concentrated HCl‐HNO3‐HF acid mixture were used to characterize the soils for organically bound, “biodiagenetically” available, and total metal content, respectively. Total metal contents were in the lower portion of ranges reported in the literature and represented levels naturally present in uncontaminated soils. Total Cd, Cr, Cu, Ni, Pb, and Zn averaged (± SD) 0.31 (±0.21), 43 (±28), 26 (±9), 21 (±14), <25, and 54 (±18) µg/g, respectively. The average extraction efficiency of HNO3 for total metals was highest for Cd (52 ± 19%) and the lowest for Cr (14 ± 7%). The predominate trend in both available and total metal content showed highest concentrations of Cd, Pb, and Zn in the surface soil and highest concentrations of Cr, Cu, and Ni in subsoil and parent materials. Cadmium was often higher in soils containing free carbonates. Concentrations of organically bound metals in soil were very low, and, with the exception of Cu, were usually negligible below the surface layer. Differences in metal content among soils were believed due to differences in the parent materials. Variations within soil series were low, with genetic horizons showing narrow ranges in HNO3‐extractable metals.
Selected Trace Elements in Plants Grown on Retorted Oil Shales
Authors: Kilkelly M. K. , Lindsay W. L. 
Published: July 2010

AbstractWestern wheatgrass (Agropyron smithii Rydb. ‘Arriba’) and fourwing saltbush (Atriplex canescens (Pursh) Nutt.) were sampled from oil shale revegetation plots in northwestern Colorado. Plants were growing on two types of retorted shales: TOSCO II, produced by the Tosco Corporation; and USBM, produced by the U.S. Bureau of Mines. Various treatments included leaching and different depths of soil covering over the retorted shales. Plant samples were analyzed for B, Mo, As, Se, and F on a dry‐weight basis. Plant samples with elevated Mo concentrations were also analyzed for Cu.Boron in western wheatgrass from the TOSCO retorted shale ranged from 85 to 202 ppm, compared with ranges of 4 to 15 ppm B in plants from the soil control. Analysis of variance indicated significant differences in B content due to site, aspect, type of retorted shale, and amount of soil cover over retorted shale. The concentration of B in western wheatgrass growing on retorted shales, especially TOSCO retorted shale, could affect plant growth. Fourwing saltbush samples, growing on USBM retorted shales, contained levels of Mo averaging 28 ppm, and low‐to‐moderate Cu content (4.8–6.8 ppm). This combination could make this species unacceptable as forage for ruminants. The concentrations of As (0.03–0.44 ppm), Se (0.02–0.94 ppm); and F (0.5–10.0 ppm) in the plant species investigated in this study were below limits usually set for either plant or animal toxicities and appear to be of little environmental significance.
Using EPA's Computerized Data Base (STORET) to Analyze for Agricultural Water Pollution
Authors: Reardon John C. , Hanson Lowell D. , Randolph John 
Published: July 2010

AbstractThe U.S. Environmental Protection Agency's computer data base (STORET) was employed to retrieve stream water quality data for a 9‐year period on an agricultural watershed in Maryland, 40 km northwest of Washington, D.C. Most of the farms in the area are large dairy operations that have waste management and storage facilities. During the study period, farmers increased their use of no‐till and minimum‐tillage corn (Zea mays L.) practices by as much as 90%, and several operators also installed animal waste‐control facilities.Total PO4, fecal coliform, and NO3 + NO2‐N data from four sampling stations in the watershed were retrieved from STORET and statistically analyzed using linear regression to relate concentration and time. The regressions indicated that concentrations of total PO4 and fecal coliform decreased with time. Total PO4 data from all four sampling stations showed a significant inverse relationship between time and concentration (5% probability or less). Of the four fecal coliform regressions, the furthest‐upstream sampling station was significant while the next one downstream approached significance (6% level). No statistical significance was evident in the NO3 + NO2‐N regression equations at any of the four stations during the 9‐year period.Results indicated that the time and costs for this type of analysis were reduced substantially by using the computer‐stored data base rather than direct sampling and laboratory analysis. A study similar to this one, but with in‐house data collection and analysis, would cost approximately 10 times more than the study reported herein.
Growth and Nutrition of White Pine and White Spruce Seedlings in Solutions of Various Nickel and Copper Concentrations
Authors: Lozano F. C. , Morrison I. K. 
Published: July 2010

AbstractAs part of an investigation of the ways in which supply is related to growth and foliage concentration, and as part of a larger problem of tree establishment on certain polluted soils, seedlings of white pine (Pinus strobus L.) and white spruce (Picea glauca (Moench) Voss) were grown from seed over a 20‐week period in nutrient solutions of various Ni and/or Cu concentrations in growth chambers. In one series, Ni was supplied during the latter part of the test period at 0, 0.01, 0.1, 1, and 10 ppm; in a second, Cu was supplied at 0, 0.01, 1, 10, and 100 ppm; and in a third, Ni and Cu were supplied together in factorial combination at 0, 1, and 10 ppm. At the end of each experiment the seedlings were harvested and growth and chemical composition were determined. In general, substantial reductions in growth occurred when concentrations of Ni and/or Cu in the nutrient solutions were ≥ 10 ppm. There was some suggestion that white spruce seedlings were more susceptible than white pine seedlings to elevated Ni levels, with the order being reversed for Cu. Foliage concentrations of Ni and/or Cu increased in relation to their concentrations in the external solutions. No definitive trends were evident in foliage concentrations of other dements except Fe and Zn, both of which decreased: Fe in relation to both Ni and Cu supply, Zn chiefly in relation to Ni supply.
Retention and Movement of Fluoride in Soils
Authors: Flühler H. , Polomski Janina , Blaser P. 
Published: July 2010

AbstractDisplacement and retention of fluoride in soils were studied in laboratory experiments. Fluoride adsorption and desorption isotherms were determined in the range of 0 to 5,000 µg mL−1 of dissolved F by shaking 1:10 soil/NaF solution suspensions. The observed relationship was nonlinear. Neither Langmuir nor Freundlich equations were unbiased predictors of the measured relationship.The experimental errors propagated in the computational analysis and made such adsorption data quite error‐prone. For soils with a low F retention the confidence interval was wide, and vice‐versa. In an acid clay soil an apparent adsorption equilibrium was attained within 3 h, but several days were required for the equilibration of the calcareous soils with the NaF solution. Adsorption and desorption of the calcareous soils exhibited a hysteretic behavior, but in the case of the acid soil no hysteresis was observed.The transport of F was studied by percolating soil columns at a constant flow rate. The F breakthrough depended primarily upon the F concentration in the infiltrating solution and soil type, whereas the ionic composition of the infiltrating solution had a less pronounced effect on the breakthrough behavior.The F retention within the soil columns and the adsorption estimates obtained from the isotherms agreed well in the case of the acid soil, but the calcareous soils retained one‐third to one‐half as much F during the percolation experiment.