bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differing Sensitivity of Corn and Soybean Photosynthesis and Transpiration to Lead Contamination
Authors: Bazzaz F. A. , Rolfe G. L. , Windle P. 
Published: July 2010

AbstractCorn (Zea mays L.) and soybean (Glycine max L.) plants grown in media containing a range of Pb concentrations, supplied as PbCl2, showed decreased net photosynthesis and transpiration with increasing Pb treatment levels. At lower Pb treatment levels, corn appears to be more sensitive than soybeans. However, at high treatment levels (62.5–250 mg/plant) soybeans are more sensitive than corn. At 250 mg Pb/plant in the medium, photosynthesis is only 10% of maximum in soybeans but 47% in corn, even though corn Pb tissue content is much higher than that of soybeans. Transpiration exhibited similar trends to photosynthesis suggesting that, especially in corn, an appreciable part of the inhibition of the two processes is related to increased stomatal resistances with increased Pb concentrations.Lead accumulation trends were similar at treatment levels of 0 to 62.5 mg/plant but were slightly different at higher levels. The total amount of Pb accumulated was higher in corn than in soybeans. Maximum accumulation in both species occurred at 62.5 mg Pb/plant.
Land Disposal of Waste Gases III. Sorption Patterns from Buried Gas Injection Pipes
Authors: Miyamoto S. , Warrick A. W. , Prather R. J. 
Published: July 2010

AbstractThe advancement of sorption fronts resulting from the injection of reactive gases into soils through buried porous pipes is analyzed mathematically and verified experimentally with small scale laboratory models. The sorption front advances in ellipsoidal patterns with faster rates above the pipes for a homogeneous profile. The reacted portion of soil when the front first intersects the ground surfaces is larger for corrugated surfaces than for plane surfaces. The corrugated surface is chosen with the “highest” elevation point directly over the injection pipe, the “lowest” point midway between. When a shallow sorptive layer overlies a nonreactive material, the shape of the front is not circular but extends towards the midpoint between parallel pipes where the most water would infiltrate. The concentration of reactants in the outflow increases sharply as the front passes a part of the ground surfaces. The sorption fronts determined experimentally by injecting a dry air and nitrogen dioxide mixture into a small soil tank agreed well with the predicted positions based on an instantaneous reaction.
Water Quality After Clearcutting a Small Watershed in West Virginia
Authors: Aubertin G. M. , Patric J. H. 
Published: July 2010

AbstractA 34‐ha (85‐acre) gaged watershed on the Fernow Experimental Forest, Parsons, West Virginia, was conventionally clearcut in 1969. Streamflow increased 20 cm (8 inches) during the first year after cutting, but rapid and luxuriant revegetation reduced the flow increase to only 6.4 cm (2.5 inches) during the second year. Water quality remained high. Clearcutting had a negligible effect on the stream's temperature, pH, nonstorm turbidity, and concentrations of dissolved solids, Ca, Mg, Na, K, Fe, Cu, Zn, Mn, and NH4+‐N. Storm‐period turbidity, nitrate‐nitrogen, and phosphate concentrations showed slight increases, while the sulfate concentration decreased. Maximum nitrate‐nitrogen concentration of 1.42 ppm was recorded during a 6.4‐cm (2.5‐inch) rainfall. Success in avoiding damage to water quality was attributed to careful road management, retention of a forest strip along the stream, and rapid, lush vegetative regrowth after clearcutting.
Diurnal Fluctuation and Movement of Atmospheric Ammonia and Related Gases from Dairies
Authors: Luebs R. E. , Davis K. R. , Laag A. E. 
Published: July 2010

AbstractSimultaneous 24‐hour air sampling, 0.8 km upwind from the nearest cows in a large dairy area (145,000 cows) and 11.2 km upwind from the dairy area, showed distillable N (mostly NH3) concentrations of 190 and 6 µg/m3, respectively. An average distillable‐N concentration of 540 µg/m3 was measured during a 24‐hour sampling at the downwind corral fence of an isolated 600‐cow dairy. These data indicate significant N loss from dairy waste by NH3 volatilization. The significance of the effects of these higher atmospheric concentrations on NH3 absorption by soils, surface waters, and crops remains to be fully evaluated. Meteorological factors, particularly temperature inversions in the atmosphere and wind, along with proximity to the waste, greatly affected atmospheric concentrations of distillable N. A marked diurnal fluctuation with low concentrations in the afternoon and high concentrations at night were frequently recorded in the large dairy area. Higher nighttime values were related to temperature inversions in the atmosphere. A reversed diurnal pattern with the high afternoon and low nighttime concentrations were recorded at the isolated‐dairy site. Close proximity to the source and a high horizontal flux of distillable N with afternoon winds were important factors in this diurnal pattern. Winds averaging 9.3 km/hour transported distillable N 500 m from the isolated dairy at a height of 1.2 m.
Nitrate and Chloride Movement in the Plainfield Loamy Sand Under Intensive Irrigation
Authors: Endelman F. J. , Keeney D. R. , Gilmour J. T. , Saffigna P. G. 
Published: July 2010

AbstractA field experiment to evaluate leaching under intensive irrigation was conducted over an 11‐day period on a Plainfield loamy sand fertilized with KNO3 and KCl. The NO3‐N and Cl concentration in soil profile and lysimeter leachate samples collected daily were determined. Under the conditions of this experiment 2.5 cm of water moved about 19 cm in the surface and 28 cm in the subsurface soil. Chloride concentrations in the profiles were similar to those of NO3‐N. Movement of NO3‐N and Cl was 15 to 20 cm/day under 2.5 cm daily water application. The results show that rainfall and/or irrigation, can rapidly move NO3‐N beyond the rooting zone of this soil.
Effect of Summer Use of a Mountain Watershed on Bacterial Water Quality
Authors: Skinner Quentin D. , Adams John C. , Rechard Paul A. , Beetle Alan A. 
Published: July 2010

AbstractThe water quality of a mountain watershed during the summers of 1970, 1971, and 1972 is presented. Samples were collected at six sample sites in the watershed. The standard plate count at 20C and the aerobic bacteria enumerated on trypticase soy agar at 20C numbered about 5 × 103 cells/ml in July, and remained at this concentration for the rest of the summer. The standard plate count at 35C was generally constant at near 50 cells/ml each summer at all sample sites. The total coliforms in 9 out of 17 cases exhibited a tenfold increase in numbers in late July or August over the values of 10 or less per 100 ml found in June. Fecal coliforms in 11 out of 17 cases increased 10 to 100‐fold in concentration in July or August over values obtained in June or September. Maximum numbers of fecal streptococci were usually seen at all sample sites in July or August except for 1972, when sheep (Ouis aries) were being grazed in September. A stream in a natural area of the watershed appeared to be less polluted than other streams in the watershed which were influenced by human use. The use of the fecal coliform to fecal streptococci ratio to determine the source of pollution appeared to be of questionable value in this study.
Effect of Flooding and Organic Matter Applications on DDT Residues in Soil
Authors: Farmer W. J. , Spencer W. F. , Shepherd R. A. , Cliath M. M. 
Published: July 2010

AbstractA field in Coachella Valley, California which had received repeated applications of technical DDT to sweet corn (Zea mays L.) for ear worm [Heliothis yea (Boddie)] control was flooded 48 days, with and without organic matter amendments, to determine whether DDT soil concentrations could be effectively reduced. Applications of 180 and 45 metric tons/ha of feedlot manure and 18 and 5.6 metric tons/ha of alfalfa (Medicago sativa L.) meal were disked to a depth of 15 cm. Redox potentials in all flooded plots rapidly dropped below −150 mV at both the 7.5‐ and 15‐cm soil depths. All flooded plots including control plots showed a rapid decrease in soil levels of DDT isomers accompanied by a rapid accumulation of the respective DDD isomers in the top 15 cm. Flooding had little effect on the DDE isomers. By the end of the flood period p,p′‐DDT had decreased from 8.1 µg/g to 0.5 to 1.6 µg in flooded plots receiving organic amendments while the p,p′‐DDD level increased from zero to 4.2 to 5.6 µg/g. The rates of disappearance of DDT and the formation of DDD were significantly lower in the flooded plots receiving no organic amendments. After 18 days flooding the rates of p,p′‐DDT losses and DDD gains were in the order of 180 metric tons/ha manure ≃ 18 metric tons/ha alfalfa > 5.8 metric tons/ha alfalfa ≃ 45 metric tons/ha manure > control. The transformation of DDT isomers to DDD isomers occurred to a lessor extent at 15–30, 30–45, and 45–50 cm soil depths. The data indicate that flooding organic matter‐amended soil effectively reduced DDT concentrations to very low levels. The fate of DDD in flooded soils is unknown. However, through the formation of DDD, the conversion of DDT to the potentially hazardous DDE is prevented.
Factors Affecting the Decomposition of an Anaerobically Digested Sewage Sludge in Soil
Authors: Miller R. H. 
Published: July 2010

AbstractCarbon dioxide evolution was used as a measure of the rate at which anaerobically digested sewage sludge is decomposed in soils. Variables included soil texture, moisture content (1/3 bar and saturated), loading rate (90 and 224/metric ton of dry sludge per ha), incubation time (1, 3, and 6 months), and temperature. Incubation temperatures were programmed to provide both diurnal and seasonal temperature variations. Sewage sludge was rather resistant to further decomposition with a maximum of 20% of the added carbon evolved as CO2 during a 6 months incubation. At the high rates employed, the rate of decomposition of sewage sludge was largely independent of differences in soil texture or chemical properties. Soil moisture content did not affect sludge decomposition in a sandy soil, but saturated conditions reduced it moderately in a silt loam soil and almost completely stopped decomposition in a clay soil. Soil temperature was the major factor influencing the rate of sewage sludge decomposition. A plot of the percentage sludge carbon evolved as CO2 vs monthly degree days was used to predict the amount of sewage sludge which would be decomposed per unit time at different soil temperatures.
Nitrogen‐15 Variations in Fertilizer Nitrogen
Authors: Freyer H. D. , Aly A. I. M. 
Published: July 2010

AbstractNitrogen‐15 concentrations of some commonly used nitrogen fertilizers are measured. Ammonium‐nitrogen has lower and nitrate‐nitrogen has higher 15N concentrations than atmospheric nitrogen. The mean difference between both is about 4 δ 15N.
Microbial Decomposition of Species of Freshwater Planktonic Algae
Authors: Mills A. L. , Alexander M. 
Published: July 2010

AbstractSuspensions of axenically grown algae underwent aerobic decomposition in a solution free of nitrogen, phosphorus, and organic carbon. The rate and extent of mineralization of algal cell carbon and nitrogen and the solubilization of algal cell phosphorus varied appreciably among the test organisms. Chlamydomonas oblonga underwent rapid decomposition; Chlorella sp. lost carbon, nitrogen, and phosphorus slowly; and Ankistrodesmus falcatus and Astemcoccus superbus lost their carbon, nitrogen, and phosphorus at intermediate rates. Microorganisms from sewage markedly influenced the rate of liberation of some of the elements contained in A. falcatus and A. superbus but had little or no effect on the mineralization of carbon and nitrogen or on the release of phosphorus from cells of C. oblonga and Chlorella sp. Cells from 14‐day cultures of C. oblonga and A. falcatus were more quickly decomposed than cells from 28‐day cultures.
The Needs for Water Quality Models on Agricultural Watersheds
Authors: Nicholson H. P. 
Published: July 2010

AbstractMan's agricultural activities contribute pollutants to surface and ground water. Preservation of water quality requires greater effort to control these pollutants including eroded soil, agricultural chemicals, oxygen‐demanding organic wastes, and sometimes heavy metals and pathogens.Management of nonpoint source agricultural pollutants will require the management of runoff or vertical movement from the source, the efficient selection and use of appropriate pesticides and fertilizers, and the retention of animal wastes and plant residues on the land. Management programs should be planned for complete drainage basins making use of existing conservation programs. Mathematical models now under development will augment current management practices and will enable the application of computer technology to prediction of the consequences of agronomic practices.
A Mathematical Model for Phosphorus Movement in Soils
Authors: Shah Dhananjai B. , Coulman George A. , Novak Lawrence T. , Ellis Boyd G. 
Published: July 2010

AbstractLand application of municipal and industrial wastes is increasingly being looked upon as an alternative for treatment of the effluent. Since phosphorus compounds constitute a major potential source of ground water contamination, it is important to study the movement of these compounds in the soil. In this paper, a model for the movement of P has been developed. Material balance equations for water in the soil pore spaces, P in the liquid phase, and adsorbed P on the soil have been formulated. These equations are solved numerically to simulate the P concentration profiles in the soil solution and in the soil as functions of depth for an operating waste disposal system. The results of the simulation show a good agreement with the field data. The model can be used to determine the response of the system for a given input of phosphates and thus is a useful tool in the design and management of such systems.
Phosphorus Movement in Soils: Theoretical Aspects
Authors: Novak L. T. , Adriano D. C. , Coulman G. A. , Shah D. B. 
Published: July 2010

AbstractThe renovation of waste water by land application shows promise because of the potential to use certain waste water nutrients to fertilize agricultural crops and to recycle these nutrients as agricultural products. In order to locate, design, and manage land treatment processes, quantitative descriptions of critical processes are required.The adsorption of P by soils is a critical process which needs to be considered. This paper compares a new model for P movement in soils with existing adsorption‐desorption models developed for chromatography and ion exchange processes. The effect of the model parameters on P movement in soils is also examined.From the new model considered here, it was found that under P adsorption, a P profile of fixed shape (shock layer) developed and moved through the soil at a speed which could be calculated from the P Langmuir adsorption isotherm, density of the soil, and the P rate of application to the soil.Model parameters have an effect on the shape of the P profile, but over the range of condition studied here, the S‐shape P front (shock layer) was less than 4 cm in thickness. The range of conditions were chosen to cover a range of soils and operating conditions which might be considered during the selection and design of a waste water land treatment process. It should not be construed from this study, that a small shock layer exists for all adsorption cases, or for the case of desorption of P from soils during leaching.
Nitrogen Conservation under Corn Planted in Quackgrass Sod
Authors: Bennett O. L. , Stanford G. , Mathias E. L. , Lundberg P. E. 
Published: July 2010

AbstractThe mechanics of growing corn (Zea mays L.) in a grass sod using the no‐tillage concept have recently been developed. However, little is known abouthe fate of fertilizers, especially nitrogen, or the potential uses of such plant species as quackgrass (Agropyron repens L.) in this management system. Silage yields of corn were determined from field studies in which corn sod‐planted in quackgrass, treated with six rates of atrazine, was compared to conventionally planted corn. The effects of no tillage and conventional tillage, using two rates of atrazine on total soil N, and N mineralization potential were compared. Yields of corn silage produced in herbicide‐treated quackgrass were significantly higher than yields from conventional tillage. In the first year, silage yields increased with rates of atrazine. Quackgrass persisted for a 2‐year period at the three lowest rates of atrazine but not at higher rates. After the first season, mineral N (largely NO3‐N) was significantly greater under untilled quackgrass than under plowed plots, However, by the following spring differences associated with tillage method had disappeared. Soil N mineralization potential, NO, and total N in the 0‐ to 15‐cm layer were considerably higher for untilled than for plowed soils. However, in untilled plots, these values were unaffected by rate of atrazine.
Fungicide Treatment of Wheat Seed: Is it Necessary?1,2
Authors: Mathre D. E. , Stewart V. R. , Johnston R. H. , Baldridge D. E. 
Published: July 2010

AbstractThe value of using nonmercury fungicide seed treatments to increase stand and yield of winter and spring wheat (Triticum aestivum L.), and to control common stinking smut (Tilletia caries [DC.] Tul.) was investigated. In a greenhouse test using soil from 38 locations in Montana, emergence from seed treated with mercury averaged 91.2% compared to 88.4% from untreated seed. Field tests using both winter and spring wheat which had been treated with various mercury or nonmercury based fungicides, failed to produce any significant increase in stand or yield.Control of common stinking smut in winter wheat with nonmercury seed treatments was accomplished, in some cases at rates lower than the label recommendation.The toxicity of the various nonmercury materials that will control common stinking smut indicates that these compounds should have less deleterious effects upon the environment than the mercury‐based seed treatments.
Trace Element Concentrations of Sewage Treatment Plant Effluents and Sludges; Their Interactions with Soils and Uptake by Plants
Authors: Bradford G. R. , Page A. L. , Lund L. J. , Olmstead W. 
Published: July 2010

AbstractMetropolitan sewage sludges and effluents were characterized in relation to their total and water extractable trace elements, their reactions with soils, and their effects on plants. The total concentrations of trace elements in sludges and effluents were highly variable depending on the source and were often much higher than concentrations found in soils. Concentrations of Cu, Zn, Ni, Co, and Cd were consistently greater in the saturation extracts obtained from sludges than those obtained from a large sampling of California soils. The effects of irrigating bean, barley, and tomato plants in a greenhouse sand culture experiment with diluted saturation extracts of sludges from different sources were all adverse but variable depending on the sludge source. Leaf samples from treated plants frequently contained toxic levels of B and excessive levels of one or more of the following elements: Cu, Mo, Ni, Co, Pb, and Cd.
Biological Denitrification and Its' Application in Treatment of High‐Nitrate Waste Water
Authors: Francis C. W. , Callahan M. W. 
Published: July 2010

AbstractOne method of removing nitrate nitrogen from waste water effluents appears to be biological denitrification. Considerable research regarding denitrification of municipal and agricultural waste water containing relatively low concentrations of nitrate (<50 ppm NO3‐N) has been conducted. However, very little research has been carried out on the feasibility of applying the process to waste water effluents which contain in excess of 1,000 ppm NO3‐N. Waste water effluents containing this magnitude of nitrates are generated in fertilizer and explosive manufacturing operations. Large quantities of nitrates are also expected to be produced at future nuclear fuel processing and uranium oxide fuel fabrication plants. This review comprehensively evaluates the various requirements for biological denitrification in respect to NO3‐N concentrations as well as quantity and type of carbon substrate and complementary cations. It also assesses which engineering design, e.g., modified activated sludge units, packed‐bed reactors, or anaerobic columns, may be most applicable in biological denitrification of waste streams containing concentrations > 1,000 ppm NO3‐N.
Influence of Treated Municipal Waste Water on Growth, Fiber, Acid‐soluble Nucleotides, Protein, and Amino Acid Content in Wheat Grain
Authors: Day A. D. , Taher F. A. , Katterman F. R. H. 
Published: July 2010

AbstractExperiments were conducted at Tucson, Arizona to study effects of treated municipal waste water on growth, fiber, acid‐soluble nucleotides, protein, and amino acid content in grain from wheat (Triticum aestivum L.). Wheat grain was grown in two soil types, (i) Comoro sandy loam, and (ii) Grabe silt loam. Three irrigation and fertilizer treatments were used: (i) well water plus suggested amounts of nitrogen, phosphorus, and potassium (112, 35, and 1 kg/ha of N, P, and K, respectively); (ii) well water plus N, P, and K from commercial sources in amounts equal to those found in waste water (224, 73, and 140 kg/ha of N, P, and K, respectively); and (iii) waste water from an activated sludge sewage plant (224, 73, and 140 kg/ha of N, P, and K, respectively).Average number of heads per unit area and grain yield were higher in wheat plots that received waste water than they were in plots that were grown with well water and suggested N, P, and K. Average days from planting to maturity, plant height, seeds per head, and seed weight were similar for the three irrigation and fertilizer treatments. Wheat grain grown with the three irrigation and fertilizer treatments contained similar amounts of total fiber and acid‐soluble nucleotides. Grain grown with waste water contained more total protein than did grain produced with well water plus suggested amounts of N, P, and K. Wheat grain that received only waste water contained more alanine, histidine, isoleucine, and proline than did grain produced with well water plus suggested N, P, and K or well water plus N, P, and K equal to waste water. Grain grown with the three treatments contained similar amounts of cystine, methionine, and threonine in all instances. High yields of high quality grain were obtained from wheat irrigated with treated municipal waste water in the southwestern United States.