bluuebunny/crossref_metadata_2025_split huggingface dataset:
Persistence and Factors Affecting Dissipation of Molinate under Flooded Rice Culture
Authors: Deuel L. E. , Turner F. T. , Brown K. W. , Price J. D. 
Published: July 2010

AbstractPesticides, essential for the economical production of rice (Oryza sativa L.), could pose a serious problem if transported to surface impoundments and estuaries along the Gulf Coast via the return flow associated with flooded rice culture.Field experiments were conducted under flooded rice cultivation to determine persistence and half‐life of molinate (S‐ethyl‐hexahydro‐1‐H‐azepine 1‐1carbothioate). Persistence and half‐life were evaluated with respect to intermittent and continuous flow irrigation schemes at normal and excessive application rates of 3.4 and 11.2 kg/ha molinate, respectively. Persistence at statistically significant levels ranged from 96 to 384 hours following the application, and generally was more a function of the application rate than irrigation scheme. Half‐life values averaged 96 ± 22 hours in intermittent flow plots, and 54 ± 17 hours in continuous flow plots over the 3‐year experiment. Application rate had little effect on half‐life.Best fit analysis of field data to the first order biological decay equation and laboratory studies under flooded soil conditions suggested that biological degradation was the principle mode by which molinate was dissipated in the field experiment.
Heterotrophic Utilization of Organic Carbon in Aquatic Environments
Authors: Sayler Gary S. , Gilmour C. M. 
Published: July 2010

AbstractField and laboratory investigations were performed to determine the contribution of dissolved organic carbon (DOC) to the eutrophication process and its effect on heterotrophic bacterial activity. Organic carbon concentrations of selected waters and waste waters from northern Idaho were determined by a modified persulfate wet combustion method. Electrolytic respirometry was employed to assess heterotrophic respiration responses to DOC in natural and enriched water samples. Concentration ranges of dissolved organic carbon furnished by sewage and glucose supplemented with micronutrients were incorporated into natural water samples taken from two experimental reservoirs. The heterotrophic bacterial response to simulated DOC enrichment was measured in terms of oxygen uptake and CO2 evolution, substrate utilization, and biomass production. Oxygen uptake was found to be the most sensitive parameter for response measurement. Results indicated growth factors or vitamin limitations occurred in some aquatic samples. Significant responses to heterogenous carbon substrates were detected at substrate concentrations commonly occurring in pristine, low DOC waters. A direct linear relationship existed between heterotrophic activity and the concentration of available DOC. Assuming no deficiency in other essential nutrients, the DOC concentration was shown to regulate the rate and net response of heterotrophic bacterial growth and activity in aquatic environments. DOC levels were found to reflect net trophic conditions unique to individual sampling locations, thereby lending itself to assays for eutrophication assessment and pollution.
Variability of Annual Nutrient and Sediment Discharges in Runoff from Oklahoma Cropland and Rangeland
Authors: Menzel R. G. , Rhoades E. D. , Olness A. E. , Smith S. J. 
Published: July 2010

AbstractNitrogen and phosphorus discharges in runoff from nearly level cropland and 3% sloping rangeland were measured from July 1972, to June 1976. Sediment discharges and runoff amounts from these 5‐ to 18‐ha watersheds were measured from July 1966, to June 1976. Sediment and nutrient discharges varied greatly from year to year and between different land uses. We concluded that long records are needed to compare discharges from different management practices. The average and maximum annual sediment discharges, respectively, were 3,600 and 8,900 kg/ha from irrigated cotton (Gossypium hirsutum), 900 and 3,900 kg/ha from dryland wheat (Triticum aestivum), 400 and 1,800 kg/ha from range with limited grazing, and 9,000 and 23,000 kg/ha from overgrazed range. Maximum annual sediment discharges occurred during the period in which nutrient discharges were measured. Maximum annual nutrient discharges were 13 kg/ha total N, 4 kg/ha nitrate N, 11 kg/ha total P, and 2 kg/ha soluble P. The average annual discharge for each nutrient form and land use was about half of its maximum value. Nitrate accounted for 10 to 30% of the total N discharged. Soluble phosphate accounted for about 20% of the total P discharged from cropland, and <10% of that discharged from rangeland. Annual deposition in rainfall averaged 5 kg/ha N and 0.15 kg/ha P.
Plutonium and Americium Contamination near a Transuranic Storage Area in Southeastern Idaho
Authors: Markham O. D. , Puphal K. W. , Filer T. D. 
Published: July 2010

AbstractFrom 1954 through 1970, transuranic waste from the Rocky Flats facility near Golden, Colorado, was shipped to the Idaho National Engineering Laboratory and buried in the Subsurface Disposal Area (SDA) at the Radioactive Waste Management Complex. Soil samples collected near the SDA indicate that this storage has resulted in transuranic contamination outside the SDA perimeter. Maximum concentrations in surface soils (0–4 cm) occurred in the drainage depression near the perimeter of the SDA and were 2,048 nCI 241Am/m2, 1,377 nCi 239Pu/m2, and 32 nCi 238Pu/m2. Contamination outside this drainage channel was lower and has primarily spread in the northeast‐southwest directions. The maximum distances from the SDA perimeter that above background concentrations of 241Am, 239Pu, and 238Pu could be detected were approximately 2,500, 2,400, and 1,000 m, respectively. Surface water runoff in 1962 and 1969 and wind transport appear to be the primary mechanisms which transported these nuclides out of the SDA. The vertical soil migration of 238Pu from 0–4 cm to the 4–8 cm depth was significantly greater than that for 239Pu (P = 0.001).Hides and gastrointestinal tracts of deer mice (Peromyscus maniculatus) had higher concentrations of transuranics than lungs or carcass. Ingestion appeared to be a more important mechanism than inhalation in the intake of transuranics into the deer mice. The 241AM/239Pu ratio in the carcass was significantly (P = 0.02) higher than the ratio in soil indicating a greater uptake of 241Am into deer mice.The data indicate that 238Pu, 239Pu, and 241Am may behave differently in the terrestrial environment.
Carbon Contents and Sources in Ground Waters of the Central Platte Region in Nebraska
Authors: Spalding R. F. , Gormly J. R. , Nash K. G. 
Published: July 2010

AbstractFifty‐one ground water samples collected in a losing reach of the Platte River were analyzed for alkalinity, dissolved oxygen (DO), dissolved organic carbon (DOC), and for the ∂13C values of DOC. Ranges in concentrations were 24.8 to 109 mg/liter, 0.0 to 5.5 mg/liter, 0.5 to 4.8 mg/liter, and −15.6 to −25.4 ‰ for inorganic carbon, DO, DOC, and ∂13C, respectively. The concentrations of these constituents are primarily associated with land use and well depth. Carbon isotope fractionation can be useful in determining sources of organic carbon to the ground water.
Cadmium Accumulation by Meadow Voles (Microtus Pennsylvanicus) from Crops Grown on Sludge‐treated Soil
Authors: Williams P. H. , Shenk J. S. , Baker D. E. 
Published: July 2010

AbstractThis investigation was conducted to measure the accumulation of cadmium (Cd), zinc (Zn), and copper (Cu) in the tissues of the meadow vole (Microtus pennsylvanicus) fed organic and inorganic cadmium. Corn (Zea mays L.) and sorghum (Sorghum bicolor L. Moench) plants were grown on soils fertilized with either inorganic or sludge fertilizer. Corn herbage fertilized with sludge was found to contain 1.82 ppm Cd and sorghum herbage contained 4.59 ppm Cd. Herbage from inorganic fertilized plots contained 0.17 ppm and 0.38 ppm Cd, respectively. Eight diets and a synthetic control diet were formulated to study these herbages. Cadmium sulfate was added to four of the diets to evaluate the effect of organic plant Cd and soluble Cd on accumulation in vole tissue. Each diet was fed to 10 animals for a period of 40 days and kidney, liver, and muscle tissue were analyzed for Cd, Zn, and Cu.Significant accumulation of Cd occurred in kidneys and livers, but not in muscles of voles fed sludge‐fertilized corn diets with 1.09 ppm Cd or sorghum diets with 2.76 ppm Cd. The form of Cd, whether organic or soluble, had little influence on tissue accumulation. Zinc and Cu accumulation in these tissues was, in most cases, nonsignificant and not associated with Cd accumulation. Weight gain, food intake, and diet digestibility were not influenced by Cd accumulation in the tissue, but the daily intake of Cd was a function of the concentration of Cd and fiber in the diet. It was concluded that diets containing 1.00 ppm Cd may cause significant accumulation of Cd in animal tissues.
Mineral Nutrition of Copper‐tolerant Browntop on Metal‐contaminated Mine Spoil
Authors: McNeilly T. , Johnson M. S. 
Published: July 2010

AbstractHeavy metal‐tolerant populations of browntop (Agrostis tenuis Sibth.) have been developed on a commercial scale in Britain for largescale restoration of abandoned metalliferous spoils. This study was carried out to clarify those aspects of the mineral nutrition of copper tolerant browntop which optimize its use in reclamation work.The effects of factorial combinations of 0, 50, and 100 kg/ha of nitrogen (N), phosphorus (P), potassium (K), and calcium (Ca as calcium carbonate) on shoot productivity of browntop on a copper‐contaminated mine spoil were examined in a glasshouse experiment. Shoots were harvested after 12 weeks and regrowth after a further 10 weeks.Significant responses at both harvests were obtained to Ca addition, and to 50 and 100 kg/ha N, whilst response to P was significant only up to 50 kg/ha. There was no response to added K.In the absence of P, N did not increase yield. Addition of 50 kg/ha P produced significantly increased yield in the 50 and 100 kg/ha N treatment at both harvests, whilst addition of 100 kg/ha P produced a further significant response at both harvests. Ca × P interaction was negative, but only significant at harvest 2.Addition of P and Ca reduced shoot metal concentrations at both harvests, whilst N addition did so only at harvest 1.The effects of nutrient addition and their differential effects at harvests 1 and 2 reflect the physical and chemical properties of the mine spoil, in particular leaching, heavy metal nutrient complexing, and its acid regeneration potential due to pyrite weathering.
Low‐Temperature Mineralization of Crude Oil in Soil
Authors: Loynachan T. E. 
Published: July 2010

AbstractPrudhoe Bay crude oil was added at 0,3, and 6% wt oil to wt of soil in a laboratory study designed to evaluate methods of enhancing crude oil mineralization at 10°C. Both mechanical stirring of the soil and fertilization were effective in enhancing mineralization. Under the most favorable conditions of the study at the 3 and 6% loading rates, respectively, only 18.9 and 11.9% of the added C was evolved as CO2. Nitrogen appeared to be the most stimulatory fertilizer; however, phosphorus in addition to nitrogen further enhanced C mineralization. Sulfur or a combined assortment of other macro‐ and micronutrients was not beneficial when added to nitrogen and phosphorus fertilizers. Sawdust was added to decrease the hydrophobic nature of oiled soils and to improve soil physical properties. Although added sawdust lessened aggregation of the stirred soil, degradation of the oil was not enhanced. Aerobic bacteria and actinomycetes were both initially active shortly after oil addition. This was followed somewhat later by population increases of bacteria growing anaerobically. Oil additions had no stimulatory effect on fungal populations. Doubling time of the net aerobic bacterial population was calculated to be 2.0 days in unfertilized soil receiving 6% oil. In fertilized soil receiving the same rate of oiling, the corresponding time was 1.2 days. Thus, fertilization decreased the doubling interval of indigenous bacteria by approximately 40% in this study conducted at 10°C.
Leaching of Cations and Chloride from Manure Applied to an Irrigated Soil
Authors: Pratt P. F. 
Published: July 2010

AbstractData for leached cations, (the sum of Ca2+, Mg2+, Na+, and K+), and leached Cl− and the ratio of cations to Cl− leached from the root zone during a 4‐year experiment with bovine manures on a Hartford soil are presented. Cation accumulation in the soil and the cations leached were linearly correlated with cation input. The removal of cations in harvested crops reached a maximum and then decreased as the input of cations increased. Leached Cl− increased at a ratio of 1:1 with the Cl− input in excess of removal in harvested crops, whereas leached cations increased with increase in inputs in excess of removal in crops and decreased with decrease in the volume of leachate. At low leachate volumes and with dry weights of liquid and solid manures at 21 and 40 metric tons/ha per year, respectively, the cations leached were less than in the check plots, indicating effective precipitation of the equivalent of the cations in the manure plus some of the cations in the irrigation water. At high leachate volumes manures increased the cations leached relative to the check treatment at all rates of manure. The dominant factor in cation leaching was volume of leachate. Carefully controlled irrigation to attain low leachate volumes combined with manure applications at reasonable rates could be used to reduce the overall effect of irrigation on the leaching of salts to ground waters.
Studies on the Uptake of Plutonium from Major Indian Soils and Its Distribution in Plants
Authors: Vyas B. N. , Mistry K. B. 
Published: July 2010

AbstractPot experiments were conducted to study the plant uptake of Pu from major Indian soil types and its distribution in plants.It was observed that, irrespective of plant species, highest amount of Pu was absorbed from acidic laterite soil baying predominantly kaolinite clay mineral and low cation exchange capacity followed by alluvial soil and was lowest in medium black alkaline soil with predominantly montmorillonite clay and high cation exchange capacity. ‘Plutonium Concentration Ratios’ for beans (Phaseolus vulgaris L.) and maize (Zea mays L.) ranged from 1.5 × 10−4 to 9.6 × 10−4 for the aerial tissues and from 13.9 × 10−4 to 15.3 × 10−4 for roots; the values for beans were higher than those for maize over identical durations of plant growth.The distribution pattern of Pu in bean plants grown to maturity in labelled nutrient solutions indicated maximum concentration of Pu in roots and a marked acropetal gradient in the aerial tissues. Further, split‐root studies indicated that Pu absorbed by roots from the soil was not subsequently released into the nutrient solution.Fractionation of Pu in freshly harvested bean pods indicated maximum amount of Pu (39.11%) to be associated with ionic forms extractable by HClO4. The levels of Pu associated with ethanol fraction (13.00%), HCl fraction (11.44%), acetone insoluble fraction (7.58%), soda fraction (11.39%), and lignin and cellulose fraction (12.24%) were next in significance. The nucleic acid fraction was found to contain the lowest levels (5.18%) of the radionuclide.
Nitrogen Inputs and Losses in Tobacco, Bean, and Potato Fields in a Sandy Loam Watershed
Authors: Cameron D. R. , De Jong R. , Chang C. 
Published: July 2010

AbstractResults from a 2‐year study concerned with additions and losses of N from cropped fields in an intensively farmed sandy loam watershed in southern Ontario indicated that heavily fertilized hurley tobacco (Nicotiana tabacum L. [Kentucky 2110]) (220 kg N/ha per year) potato (Solanum tuberosum L. [Superior]) (165 kg N/ha per year) fields can potentially lose up to 52 and 92 kg N/ha per year, respectively, from the 75‐cm profile by leaching and denitrification. Mineral N production rates calculated from results obtained in the field over the growing season varied from 0.0 to 0.73 kg N/ha per year. The lower rate resulted from leaching losses. The monitored NO3‐N profile distributions under fertilized hurley tobacco and potato crops showed definite leaching patterns. Soil water samples taken periodically from the potato field at 90 and 150 cm showed NO3‐N moving through the lower profile in response to rainfall events. A plot treated with Cl showed no significant Cl leaching losses until early fall when rains moved about 45% of the added Cl below 75 cm.
Design of an Air Pollution‐Monitoring Network for Tehran
Authors: Massoudi M. S. , Rashidi M. , Shadman F. 
Published: July 2010

AbstractTehran, like other large metropolitan areas throughout the world, is challenged by environmental problems associated with rapid growth and economic expansion. The severity of the problem in Tehran suggested that there was a need for an air‐monitoring program. It was proposed that the monitoring program be time phased. The first monitoring phase began 1 year ago and involved installation of a central station. The common pollutants that have been measured in this program are sulfur dioxide, carbon monoxide, oxides of nitrogen, ozone, methane, nonmethane hydrocarbons, and particulates. This station has mechanical weather instruments to measure wind speed, wind direction, and temperature to obtain some information about the micrometeorology of the Tehran Basin.The second phase will involve the installation of 10 small single stations. These stations are to be equipped with weather instruments and simple and reliable equipment for measuring NO2, SO2, CO, and particulates. The equipment selected includes high‐volume samplers and NO2 and SO2 bubblers. This phase will start shortly and last for a year.The last phase of the program will involve the design, fabrication, and installation of more sophisticated stations. The factors affecting the station siting have been studied. The information needed for the design of the equipment for any of the final stations has been investigated. The data on the trends of the ambient concentration of the main pollutants in Tehran was collected for a period of 4 mo from April through July 1976. Typical diurnal variations in the gaseous pollutant concentration and cumulative frequency distributions of these pollutants are presented in this paper.
Effect of Environmental Factors on Survival of Salmonella typhimurium in Soil
Authors: Zibilske L. M. , Weaver R. W. 
Published: July 2010

AbstractSalmonellae have a wide host range that includes cattle and humans. Appoximately 10% of the cattle excrete this microorganism in their manure. Most manure is ultimately disposed of on soil with little pretreatment. The survival times of salmonellae in soils varies greatly. This investigation was undertaken in the laboratory to determine how accurately salmonella survival can be predicted when environmental conditions are known. Salmonella typhimurium was inoculated into two Texas soils, a clay and a fine sandy loam, using cattle manure slurry and saline as inoculum carriers. Soil samples were incubated in the laboratory at three temperatures and moistures: 5, 22, and 39°C; and 0, 0.5, and >22 atm tension, respectively. Survival was monitored for 12 weeks by direct spread plating of soil dilutions onto dulcitol‐iron thiosulfate (DIT) medium developed for this experiment. The DIT medium restricted growth of normal soil microflora but allowed growth and differentiation of S. typhimurium. Statistical evaluation of treatment effects was complex because of three factor interactions. Soil moisture and temperature interacted as did soil moisture and inoculation method. Time as a factor strongly interacted with moisture, soil, and temperature. S. typhimurium died within 1 week in dry soil incubated at 39°C. For some treatment combinations incubated at 39°C, interactions occurred that resulted in survival to 42 days. Survival at 5 and 22°C was comparable and usually longer than at 39°C. Salmonella populations increased in some samples at 3 days but declined afterward.
Residual Effects of Irrigating Corn with Digested Sewage Sludge
Authors: Hinesly T. D. , Ziegler E. L. , Barrett G. L. 
Published: July 2010

AbstractThe same corn hybrid (Zea mays L.) was grown during the last 3 years that Blount silt loam plots were irrigated with liquid, municipal sewage sludge and for the next succeeding 4 years after termination of applications. During the last year in which sludge was applied, leaves from maximum sludge‐treated plots contained 112 mg Zn/kg and 7.1 mg Cd/kg. Four years after sludge applications were terminated, leaves from these plots contained 45 mg Zn/kg and 2.1 mg Cd/kg. Grain‐Zn concentrations decreased from 45 mg Zn/kg during the last year of sludge applications to 27 mg/kg in the 4th year after termination of applications. In a similar manner, grain‐Cd concentrations decreased from 0.44 to 0.07 mg/kg. During the 3rd and 4th years after terminating sludge applications, grain from sludge‐treated and control plots could not be distinguished by differences in Zn and Cd concentrations. Soil pH was near neutral throughout the study and was not affected by treatments. Except for the decrease during the first year after which sludge applications were terminated, total N and organic‐C concentrations in previously sludge‐amended soil remained fairly constant at levels markedly higher than in control plots. The cation exchange capacity of the soil was increased in proportion to the amount of organic‐C remaining in the soil after termination of sludge applications.
Contribution of Nitrogen and Phosphorus to Subsurface Drainage Water from Intensively Cropped Mineral and Organic Soils in Ontario
Authors: Miller M. H. 
Published: July 2010

AbstractNutrient content of tile drainage water was measured continuously from six mineral soil sites during 1972 and 1973 and from three organic soil sites during 1972 to 1975. The sites ranged in size from 5 to 113 ha and varied in cropping and fertilization practices.Average weekly concentrations of NO3‐N in drainage water from mineral soils which were fertilized at or below recommended rates seldom exceeded 10 mg/liter, whereas those from sites fertilized at rates greater than recommended were seldom below 10 mg/liter. Annual NO3‐N contribution ranged from 4 to 64 kg/ha with the larger amounts associated with those sites fertilized at rates greater than recommended.Average annual concentrations of NO3‐N in drainage water from organic soils ranged from 14.8 to 42.7 mg/liter and the average annual contribution ranged from 37 to 245 kg/ha. The PO4‐P concentrations in drainage water from the organic sites increased markedly during the course of the study and averaged 18.2 mg/liter on one site for the 1974/1975 drainage period. Laboratory leaching studies indicated that the high PO4‐P concentrations could be attributed to fertilizer use. Laboratory studies also indicated that the P‐adsorption capacity of organic soils in southern Ontario varied widely depending on the total Fe and Al contents of the samples. It is suggested that the P‐adsorption capacity should be considered before organic soil areas are developed for crop production.