bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sludge Application to Land Compared with a Pasture and a Hayfield: Reduction of Biological Health Hazard Over Time
Authors: Wallis P. M. , Lehmann D. L. , Mac Millan D. A. , Buchanan‐Mappin J. M. 
Published: July 2010

AbstractEconomic and environmental pressures favor the disposal of sewage sludge on agricultural land. In order to assess this hazard, this study investigated the occurrence and survival of primary and secondary bacterial pathogens, parasite eggs, and enteroviruses in sludge injected by machine into a fallow field, sludge spread on a grass plot (Poa spp. and Fescue spp.), a pasture grazed by cows (Bos taurus), and on soil taken from a control hayfield (dominated by Bromus spp.). It was assumed that the unsludged hayfield represented an acceptable level of “risk.”The sludged plots compared favorably with the control hayfield with respect to the occurrence and survival of nematode parasites, enteroviruses, and primary bacterial pathogens. Secondary bacterial pathogens persisted on all fields throughout the study, but levels declined more slowly on the sludged grass plot than the injected sludge field, the pasture, or the control hayfield. Despite the persistence of secondary pathogens (which are normally present on grazed fields), the health hazards to humans and animals were judged to be comparable to those on a hayfield and a pasture that had not been sludged.
Research on the Response of Vegetation to Elevated Atmospheric Carbon Dioxide
Authors: Dahlman Roger C. , Strain Boyd R. , Rogers Hugo H. 
Published: July 2010

AbstractThe global rise in atmospheric CO2 is an established phenomenon. Irrespective of whether a CO2‐induced climate change occurs, it is abundantly clear that the earth's mantle of vegetation will be directly affected by increased CO2 levels. Carbon dioxide is essential for plant growth (plants obtain C from CO2 in the atmosphere); a higher level of CO2 will increase the rate of photosynthesis. Quantitative information on the CO2‐induced growth response for field situations is needed for assessments of (i) possible benefits to agriculture, (ii) the amount of fossil C that can be sequestered by CO2‐accelerated growth of the biosphere, and (iii) unknown or unidentified effects of CO2 on the physiology, structure, and function of plants and ecosystems. Along with knowledge of CO2 effects on climate and other factors, information on direct plant effects will be used in comprehensive evaluations of policy options related to increasing atmospheric CO2. Herein, a discussion of the plan by the U.S. Department of Energy (DOE) to address the CO2 problem is presented along with research results from two programs, one agricultural and the other ecological.
Swine Lagoon Effluent Applied to ‘Coastal’ Bermudagrass: III. Irrigation and Rainfall Runoff
Authors: Westerman P. W. , Overcash M. R. , Evans R. O. , King L. D. , Burns J. C. , Cummings G. A. 
Published: July 2010

AbstractIn moisture excess regions, irrigation of lagoon effluent to land is generally required to prevent water pollution from lagoon overflow. However, the land area receiving lagoon effluent then becomes a potential nonpoint source of pollution, especially if effluent is applied at high rates.The quantity and quality of rainfall runoff were determined for 6 yr from plots of ‘Coastal’ bermudagrass [Cynodon dactylon (L.) Pers.] on typical Coastal Plains soils that received weekly irrigations of swine (Sus scrofa domesticus) lagoon effluent during the growing season. Three application rates supplied an average of 335, 670, and 1340 kg N ha−1 yr−1; 90, 180, and 360 kg P ha−1 yr−1; and 200, 400, and 800 kg Cl− ha−1 yr−1.The soil‐crop characteristics promoted high infiltration of rainfall and the plots were not irrigated during the nongrowing season, when runoff is usually highest. Thus, both runoff volume and nutrient mass transport were low, but nutrient concentrations were relatively high compared with typical concentrations in cropland runoff. Average annual arithmetic mean concentrations ranged from 7 to 13 mg L−1 for total N and from 3 to 6 mg L−1 for total P for the three treatments. Treatment differences were usually significant for the high‐rate treatment, but not significant between the low‐ and medium‐rate treatments. For this soil‐crop system, NO3−‐N movement to groundwater and P accumulation in the soil for the high‐ and medium‐rate treatments would likely be of more concern than the pollution of rainfall runoff.
Nodule Activity in Soybean Cultivars Exposed to Ozone and Sulfur Dioxide
Authors: Jones A. W. , Mulchi C. L. , Kenworthy W. J. 
Published: July 2010

AbstractIn an effort to obtain a greater understanding of the mechanisms of action for air pollutants on yield‐limiting processes in crop plants, studies were conducted in the field and greenhouse in 1979 to investigate the effects of O3 and SO2 exposures on nodule activities in roots and chlorophylls a and b contents in leaves of soybeans [Glycine max (L.) Merr.]. Six cultivars of soybeans were exposed 4 h d−1 for 5 successive days during flowering and pod development to the combination of 6.7 µmol m−3 O3 and 11.1 µmol m−3 SO2 in activated charcoal‐filtered air. Acetylene reduction procedures were used to assay nodule activities.Significant differences (P < 0.1) were observed in total nodule activity (TNA) per plant for treatments and cultivars in combined analysis of variance (ANOVAs) for two greenhouse studies and two exposure dates in the field; however, treatment × cultivar interactions were nonsignificant in all cases. Compared with filtered air controls, the air pollution treatment reduced TNA by an average of 16.4 and 27.4% in the greenhouse and field studies, respectively. Specific nodule activities (SNA) were unaffected by the treatments in both studies. In the greenhouse studies, the O4 and SO2 treatment lowered the chlorophyll a content by 14.1%, but no significant differences were observed in the field study. Chlorophyll b contents were unaffected by treatments in both investigations. In these studies, the sensitivity of changes in chlorophyll contents in soybean leaves following exposures to O3 and SO2 at concentrations found in the atmosphere were found to be too low to be of practical value for screening plants for tolerance to air pollutants.
Effect of Acid Precipitation on Soil Microbial Activity: II. Field Studies
Authors: Bitton G. , Volk B. G. , Graetz D. A. , Bossart J. M. , Boylan R. A. , Byers G. E. 
Published: July 2010

AbstractThe effects of acid precipitation on selected microbiological processes were investigated under field conditions. The study site, near Lake McCloud, FL, was composed of three transects, each including three plots. Each transect was spray‐irrigated with lake water at various levels of acidity. Acid rain did not significantly reduce dehydrogenase, phosphatase, or urease activity; protease activity was decreased. Similarly, soil respiration was not altered by acid rain of pH 3.7 or 3.0. It was, however, observed that acid rain significantly reduced nitrification at both pH levels. Laboratory and field data were compared and discussed.
Butanol Degradation and Volatilization in Soils Amended with Spent Acid or Sulfuric Acid
Authors: Fairbanks B. C. , Schmidt N. E. , O'Connor G. A. 
Published: July 2010

AbstractButanol persistence may be an important consideration in determining the phytotoxic effects of alkylation spent acid added to soils. The degradation and volatilization of n(1‐14C)butanol were thus monitored in two calcareous soils from New Mexico amended or unamended with spent or reagent grade sulfuric acids. Degradation of butanol to CO2 was rapid and was the primary mechanism of loss from these soils. After 20 d, 14CO2 evolution averaged 58 and 51% of the added 14C for Glendale clay (Typic Torrifluvents) and Lea sandy loam (Petrocalcic Paleustolls), respectively; a majority of this loss occurred within 2 d. Acid type (spent or reagent grade) did not affect degradation, but 14CO2 production increased with acid rate. Volatilization was essentially complete within 1 d and averaged 8 and 16% of the added 14C for the Glendale clay and Lea sandy loam soils, respectively. Acid rate, but not acid type, affected volatilization loss. The summation of degradation and volatilization losses was similar for both soils and averaged 67% after 20 d, a majority of which was lost within 2 d.
Rates of Iron Sulfide Oxidation in Coal Spoil Suspensions
Authors: Evangelou V. P. , Grove J. H. , Rawlings F. D. 
Published: July 2010

AbstractRates of pyritic coal spoil oxidation were studied in water suspensions of each of two particle‐size fractions (< 0.5 mm and 0.5–2 mm). The treatments on each of the size fractions included liming with reagent grade CaCO3 at rates of 0, 14.4, and 28.8 g kg−1. In another treatment, toluene was added to unlimed suspensions to inhibit microbial growth.The greatest rate of salt formation (taken as a measure of pyrite oxidation) was associated with the larger size fraction. Toluene suppressed the oxidation‐dissolution rate, suggesting a microbial role in pyrite oxidation in these systems. The application of CaCO3 at 14.4 g kg−1 spoil to the 0.5‐ to 2.0‐mm size fraction enhanced the oxidation‐dissolution process during the initial phase of the reaction (0–100 min). When the larger size fraction was amended with CaCO3 at a rate of 28.8 g kg−1, three rates of oxidation‐dissolution were apparent. The first rate was attributed to dissolution of indigenous sulfate salts. The second rate was attributed to oxidation of a more reactive pyrite fraction than that described by the third rate (slowest rate). This last rate was attributed to a nonmicrobial oxidation pathway due to the higher pH values observed in the suspension.
Nitrogen Availability and Uptake from Field Soils Five Years after Addition of Sewage Sludge
Authors: Harding S. A. , Clapp C. E. , Larson W. E. 
Published: July 2010

AbstractNitrogen availability and uptake from sewage sludge were studied in a field experiment during 1979 on a Hubbard sandy loam soil (Entic Haploboroll). Treatments of anaerobically digested (low, 6370; medium, 12 770; and high, 25 200 kg N ha−1), aerobically digested (12 540 kg N ha−1) and waste‐activated (24 500 kg N ha−1) sludge were applied between 1972 and 1974. By 1975, 50% more total N remained in plots receiving anaerobic sludge than in plots receiving equivalent N rates of waste‐activated or aerobic sludge. By 1979, only 12% of the 1975 level of potentially mineralizable N (N0) remained in the waste‐activated sludge plots, followed by anaerobic sludge (3, 11, and 9% in the low, medium, and high levels, respectively) and aerobic sludge (2%). In 1979, N uptake by maize (Zea mays L.) ranged from 67 kg N ha−1 to 184 kg N ha−1 on sludge‐treated plots and was 158 kg N ha−1 on fertilized controls [250 kg N ha−1 as (NH4)2SO4; 0 sludge]. Due to early depletion of N0 in aerobic sludge and slow current rate of mineralization of N0 in waste‐activated sludge, N uptake in 1979 from those sludge treatments was 51 and 58%, respectively, as high as from equivalent N application rates of anaerobic sludge. Maize grain and fodder yields reflected the uptake differences. In the 0‐ to 15‐cm soil depth, mineral N at planting time ranged from 23 kg N ha−1 in aerobic and low anaerobic treatment plots to 31 kg N ha−1 in medium and high anaerobic treatment plots. Multiple regression analysis indicated the effect of residual mineral N at planting time was more important than N mineralized during the season for both amount and efficiency of N uptake. Low residual NO3−‐N in the 0‐ to 15‐cm depth limited maize uptake of N mineralized during the season and of previously mineralized N present below the 45‐cm depth. The relative influence of residual mineral N on N uptake changed after sludge application. Therefore, combined N indexes and decay series should be used when estimating long‐term N supplying power of high sludge applications.
Effects of Anaerobically Digested Poultry Manure on Soil Phosphorus Adsorption and Extractability
Authors: Field J. A. , Reneau R. B. , Kroontje W. 
Published: July 2010

AbstractResearch in the past has indicated that large additions of animal manures to soil can reduce soil P adsorption and increase P extractability. However, application rates used in many studies are unrealistic with respect to crop fertilization and land disposal due to the excessive quantities of N applied with the manures. The objective of this study was to evaluate effluent from a poultry manure anaerobic digester applied to a Hayesville loam soil (clayey, oxic, mesic, Typic Hapludult) on soil P adsorption and extractability after three incubation periods (0, 30, and 90 d). Effluent solids were applied at rates corresponding to 753 through 7530 mg N kg−1 soil.Langmuir equation parameters (from least square fitted data; R2 > 0.98) were used as a basis to compare the influence of treatments on P adsorption properties of the soil. The P adsorption maxima parameter was not influenced by any of the effluent treatments. The parameter related to P bonding energy of the soil was reduced 33 and 41%, respectively, by mid and high rate effluent applications. A similar reduction was not observed for the low rate treatment, which corresponded to fertilizer application of 100 mg N kg−1 soil.Extractable soil P increased in a predictable manner with increased effluent solids application for all three incubation periods. These increases in extractable P could be described by linear regression equations. The slopes of these lines indicate that a 1‐g addition of effluent solids to 1‐kg soil accounts for increases in extractable P of 3 to 6 mg kg−1.
Irrigation of Forages with Rendering Plant Wastewater: Forage Yield and Nitrogen Dynamics
Authors: Bole J. B. , Gould W. D. 
Published: July 2010

AbstractWastewater from an animal by‐product rendering plant containing N, P, and biochemical oxygen demand (BOD) at greater than 500, 60, and 500 mg L−1, respectively, was applied to irrigated forages to study the suitability of forage species and the fate of applied nutrients. Applications of 10 and 20 cm yr−1 supplied the nutrients at rates in excess of crop requirements. The treatments were compared with irrigation water and with water supplemented with either fertilizer N and P or C as sugar at rates similar to those in the wastewater. Reed canarygrass (Phalaris arundinacea L.) yields were doubled by the application of 10 cm yr−1 of wastewater as compared with irrigation water treatments, but alfalfa (Medicago sativa L.) yields were not significantly affected. Doubling the wastewater application rate or adding comparable rates of N and P fertilizer did not further increase yields. The wastewater‐irrigated alfalfa contained NO3−‐N levels of 1500 to 1600 mg kg−1 plant material, while reed canarygrass contained about 3000 to 3400. Both these levels would be considered potentially unsafe for livestock feed. There was an accumulation of soil NO3−‐N levels of up to 30 to 40 mg kg−1 soil throughout the surface 120 cm of soil after 5 yr of irrigation with 10 cm yr−1 of wastewater and two to three times this level with 20 cm yr−1 of wastewater. Higher levels of NO3−‐N were observed in the soil when N was applied as fertilizer. Soil NH4+‐N levels were not greatly affected. A nitrogen balance over 6 yr at the high application rate suggested plant uptake, soil NO3−‐N, and losses accounted for 30, 25, and 45% of wastewater N and 29, 39, and 32% of fertilizer N. A 1‐yr 15N balance after 3 yr of irrigation indicated uptake, soil NO3−‐N, and unaccounted‐for N was about 10, 19, and 71% for wastewater and 15, 33, and 52% for fertilizer N. The greater losses of wastewater N compared with fertilizer N were attributed to enhanced denitrification due to oxidizable C in the wastewater. Attempts to simulate this effect with C as sugar were not effective.
Adsorption and Desorption of Hexavalent Chromium in an Alluvial Aquifer Near Telluride, Colorado
Authors: Stollenwerk K. G. , Grove D. B. 
Published: July 2010

AbstractA laboratory investigation of reactions between hexavalent chromium [Cr(VI)] and alluvium was conducted to evaluate reactions of Cr(VI) contaminating an alluvial aquifer near Telluride, CO and to determine the mechanisms responsible for these reactions. Uncontaminated alluvium and groundwater (spiked with CrO42−) from the study site were used in batch and column experiments. Results of these experiments show that Cr(VI) was adsorbed by the alluvium. Distribution coefficients from batch experiments ranged from 52 L/kg at an equilibrium CrO42− concentration of 0.4 µmol/L to 1.7 L/kg at an equilibrium concentration of 1400 µmol/L. The zero point of charge for the alluvium was approximately 8.3, and the alluvium had a positive net charge at the groundwater pH of 6.8. Visual and chemical evidence indicated that Fe oxide and hydroxide coatings on the alluvial particles principally were responsible for the adsorption of Cr(VI). During column experiments, Cr(VI) initially was desorbed easily from the alluvium by Cr‐free groundwater; however, the rate of desorption decreased rapidly, and > 60 pore volumes of groundwater were required to decrease the effluent concentration of Cr(VI) to 3 µmol/L [drinking water standard for Cr(VI) = 1 µmol/L]. The quantity of Cr(VI) adsorbed varied with the type and concentration of other anions in solution.
Effect of Sludge Application on Physical Properties of a Silty Clay Loam Soil
Authors: Wei Q. F. , Lowery B. , Peterson A. E. 
Published: July 2010

AbstractThis study was conducted to elucidate the long‐term effect of dewatered sludge application on a silty clay loam soil, which possesses poor permeability and other undesirable physical properties. A Zimpro®‐processed dewatered sludge was applied in early 1977 at treatment rates of 0, 11.2, 22.4, 44.8, and 112.0 Mg ha−1 (dry solids basis) to a Kewaunee silty clay loam soil (Typic Hapludalf). A sixth treatment was an annual application of 22.4 Mg ha−1 from 1977 to 1982, resulting in a total input of 134.4 Mg ha−1.Bulk density, infiltration, hydraulic conductivity, and aggregate stability were measured $ yr after application (note: fifth year of annual sludge application at 22.4 Mg ha−1). The bulk density decreased by 0, 0.7, 3.5, 8.3, and 6.3% over the control for the 11.2, 22.4, 44.8, 112.0, and 134.4 Mg ha−1 of sludge treatment, respectively. The hydraulic conductivities of saturated soil cores were 0, 4.2, 45.4, 70.2, and 70.6% higher for the 11.2, 22.4, 44.8, 112.0, and 134.4 Mg ha−1 sludge treatment, respectively, over the control. The improved soil permeability was due to the enhancement of aggregate stability, which increased relative to the control by 3.3, 9.4, and 11.9% with the 44.8, 112.0, and 134.4 Mg ha−1 treatment, respectively. The in situ volumetric moisture content of the sludge‐treated soils was always higher than the control, especially after a prolonged period of evaporation. At 33.3 kPa or less, more water was released from soils treated with high rates of sludges. This indicated an increase in the volume of larger pores, which resulted in the higher hydraulic conductivities.Lower rates of sludge treatments (11.2 and 22.4 Mg ha−1) had no effects on the soil physical properties after 5 yr. Small yearly applications improved the soil physical properties equally as well as a single large application.
Percolation Tests, Soil Texture, and Saturated Hydraulic Conductivity in Lacustrine Soils in North Dakota
Authors: Conta J. F. , Richardson J. L. , Prunty Lyle 
Published: July 2010

AbstractPercolation tests were unreliable estimators of in situ saturated hydraulic conductivity (Ksat) if the data were to be used to predict soil permeability for on‐site septic disposal systems in soils with > 0.35 kg/kg clay (r = −0.38 [nonsignificant], p = 0.01). The wide variations in percolation rates (10.5–135.9 min/cm) measured on similar pedons with silty clay or clay textures were attributed to the pedal nature and vertic properties that exist in high clay content soils of the area. Percolation rates yielded good estimates of Ksat in soils with < 0.35 kg/kg clay (r = −0.79**, p = 0.01) (** indicates significance at the 1% level). The soil clay content and Ksat rate correlated with sufficient precision over a wide range of soil textures for clay content to be used in predicting permeability and to permit using permeability to interpret the soil suitability for septic absorption fields. This research showed that clay content could reliably form the basis of a sanitary code.A comparison of in situ Ksat rates and estimated permeability ranges used by the Soil Conservation Service revealed that many fine‐textured soils have permeabilities greater than the Soil Conservation Service ranges indicate. The ranges of permeability should be expanded for these fine‐textured soils to include more rapid permeabilities.
Laboratory Investigation of Leachate Chemistry from Six Appalachian Forest Floor Types Subjected to Simulated Acid Rain
Authors: De Walle D. R. , Ribblett G. C. , Helvey J. D. , Kochenderfer J. 
Published: July 2010

AbstractIn order to determine the role of the forest floor in neutralization of strong acidity in acid rain, simulated acid rain at pH 4.0 was applied under laboratory conditions to forest floor samples from six Appalachian forest types. Effects of forest type, storm size, and repeated storm applications on leachate chemistry were investigated. Forest floor leachate from a hemlock forest [Tsuga canadensis (L.) Carr.] showed significantly lower pH (mean pH 3.9) than other leachate types due to high concentrations of organic acids. Cove hardwood forest found in an area with calcareous soil parent material produced forest floor leachate with a significantly higher pH (mean pH 6.5) than other forest types. Forest floor leachates from mixed oak (Quercus spp.), northern hardwood, red pine (Pinus resinosa Ait.), and white pine (P. strobus L.) forests were intermediate in pH (mean pH 4.1–4.4) due to the acidifying influence of organic acid leaching balanced against the neutralizing effect of H+ exchange for Ca2+ in the forest floor. Weak acidity concentrations obtained by Gran plots were well correlated with 400‐nm wavelength transmittance and anion deficits in the leachates. Organic anions dominated leachates from hemlock and mixed oak forest types. Increasing storm sizes caused reduced ionic concentrations, especially of H+, Mg2+, and Ca2+, but three repeated storms produced no consistent significant reductions in loads or concentrations.
Long‐Term Phosphorus Sorption in a Brunisol in Response to Dosed‐Effluent Loading
Authors: Nagpal N. K. 
Published: July 2010

AbstractPhosphorus sorption characteristics of a major soil in the Shawnigan Lake area of Vancouver Island were studied in response to periodic secondary effluent loading. Five soil columns 0.60 m long and 0.139 m in diam were prepared from the B horizon of the Shawnigan gravelly silt loam (classified as a Dystric Brunisol and Typic Dystrochrept according to the Canadian and U.S. Systems of soil classification, respectively). Water table level was maintained at the base of the two partially saturated columns (PSC). The other three columns (USC) remained unsaturated at all times and were subjected to a tension of 6.0 kPa. A single, daily dose of 1 L (∼6.6 cm) of secondary effluent was applied to all columns except on weekends and holidays.The effluent P was retained effectively by the USC columns initially, but broke through with time as in case of the PSC columns. The leachate P concentration reached an equilibrium value (EPC) after about 70 pore volumes of effluent had passed through the columns. The EPC changed only slightly beyond 70 pore volumes, but was a function of effluent P concentration and percolation rate. About 60 to 90% of added P was retained by the columns, even after 2.7 yr of leaching. Surface layers were the most effective renovators of effluent P; however, the total amount of P retained by the soil was dependent more on effluent percolation rate and leaching period, and less on water table level.