bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Sulfur Dioxide on Algae
Authors: Wodzinski Richard S. , Alexander Martin
Published: July 2010

Photosynthetic activity in soil of pH 7.1 was unaffected by a 10‐day exposure to 0.5 ppm sulfur dioxide (SO2) in air. However, the photosynthetic activity of Anabaena flos‐aquae and Chlamydomonas reinhardtii suspended in a thin layer of medium at an initial pH of 6.0 was almost totally inhibited within 24 hours by treatment with 1.0 ppm SO2 in air. The pH of the medium decreased to 5.2 or below during this period. If the decrease in pH was prevented by the addition of soil or phosphate buffer, no inhibition of photosynthesis was observed. In contrast, addition of an acidic soil to a medium of pH 4.9 offered no protection from the adverse effects of SO2. The data indicate that the decrease in pH of samples exposed to SO2 was not the sole cause of the inhibition of photosynthetic activity.
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

Pesticides, 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

Field 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

Nitrogen 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

From 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

Fifty‐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

This 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

Heavy 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

Prudhoe 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

Data 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

Pot 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

Results 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

Tehran, 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

Salmonellae 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

The 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

Nutrient 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.
Nitrogen and Chloride Movement in Small Upland Piedmont Watersheds: I. Nitrate‐Nitrogen and Chloride Distribution in Soil Profiles
Authors: Langdale G. W. , Leonard R. A. , Fleming W. G. , Jackson W. A.
Published: July 2010

Soil profile characteristics of many soils are related to the partitioning of fertilizers for soil pool, plant uptake, overland transport, and deep seepage. Chloride and NO3‐N distribution patterns were studied on variable soil profiles of two small agricultural watersheds planted to corn (Zea mays L.). Management variables included grassed waterways, graded terraces, and winter rye (Secale cereale L.) cover crops. Landscape slope and soil characteristics of the surface and control section layers were inherent variables within and among watersheds. Average soil Cl concentrations decreased from 275 ppm to background levels (30 ppm) at the 0‐ to 8‐cm soil depth within 40 days after spring‐incorporated applications of Cl fertilizer (112 kg Cl/ha as KCl). Nitrogen fertilizers (∼140 kg N/ha per year) were applied in split applications to meet optimum corn‐growth demands. Average NO3‐N concentrations ranged from 20 to 40 ppm at the 0‐ to 8‐cm depth immediately after N‐fertilizer applications, but decreased rapidly because of biological assimilation. Nitrate‐N below 25‐cm soil depths were consistently ± 10 ppm and unrelated to watershed management or soil characteristics because of the low concentrations. Chloride distribution in soil profiles was significantly related to the depth of the B21t soil horizon below the soil surface and to surface soil texture only when the B21t horizon was uniformly located in the soil profile. Most anions available for leaching are below the B21t horizon following summer leaching, and move below the soil solum during winter leaching. A Cl balance suggests that most unaccounted for N (30 kg/ha) may be lost through winter leaching or denitrification. Recommended applications of applied N‐fertilizer for corn production provide little opportunity for overland transport and small increases in deep seepage during winter months to drainage waters. Heavy applications of Cl in April or May suggest that similar applications of commercial N‐fertilizers have little chance of overland transport because of rapid movement below the surface cm depths. The overland transport quantities may increase significantly on severely eroded Piedmont soils because of shallow B21t horizons and usually steep slopes associated with these lands.
Nitrogen and Chloride Movement in Small Upland Piedmont Watersheds: II. Nitrogen and Chloride Transport in Runoff
Authors: Langdale G. W. , Leonard R. A. , Fleming W. G. , Jackson W. A.
Published: July 2010

Selective management practices were used on two upland Southern Piedmont watersheds to assess their influence on overland transport of Cl, soluble‐N, and total Kjeldahl‐N (TKN). Ammonia‐N and TKN were measured in both runoff water and sediment phases and related to these transport modes. Chloride (112 kg Cl/ha) served as a tracer anion because of its inert biological activity. Optimum rates of N‐fertilizer (∼140 kg N/ha) were applied in recommended split‐applications for corn growth. Annual NH4‐N and TKN losses were 35 to 40% less when associated with terraces and double cropping of corn (Zea mays L.) and winter rye (Secale cereale L.) than from a watershed without conservation practices. This difference was related primarily to differences in sediment yield from the two watersheds. No real annual differences were detected for Cl and NO3‐N losses between watersheds. Total seasonal nutrient losses were strongly affected by the quantity of sediment transported during highly erosive periods of May, June, and July. Chloride and TKN concentrations in runoff were more constant among cropping seasons; therefore, individual storm yields were best related to runoff water volume. Nitrate‐N and NH4‐N concentrations in runoff decreased rapidly during corn canopy development causing the quantity of these N species to be best related to sediment transport. An inadequate number of runoff storms occurred during these short periods of high soil chemical concentrations, derived from Cl‐ and N‐fertilizer sources, in the surface depth (0 to 8 cm) to significantly develop a relation to runoff concentrations. Runoff water and sediment variation accounted for 82 to 93% of nutrient loss variation on the nonconservation watershed. The same variables accounted for as little as 61% of the nutrient variation on the conservation watershed. Runoff losses of plant nutrients may be reduced by shifting most of their application to periods of rapid plant canopy development and periods of less intense rainfall.
Effects of Sludge Applications on Soil Water Solution and Vegetation in a Northern Hardwood Stand
Authors: Koterba Michael T. , Hornbeck James W. , Pierce Robert S.
Published: July 2010

Dewatered and limed sludge from a primary treatment plant was applied at two rates, 25 and 125 wet metric tons/ha (5.8 and 28.0 dry metric tons/ha), on sandy loam soils in a northern hardwood forest in central New England. Changes in soil water solution were assessed from water samples collected with suction lysimeters at 20‐ and 45‐cm depths below the mineral surface. The light application of 25 metric/ha had little effect, but the heavy application of 125 metric tons/ha caused an increase in the concentration of most ions in soil water. At 20 cm, or just below the B21h horizon, Cl reached a mean maximum of 27.5 mg/liter after heavy application compared to control values of <0.4 mg/liter. Sulfate rose above mean background levels of 5.0 mg/liter to a maximum concentration of 13.5 mg/liter. Mean Ca values rose to over 13.5 mg/liter compared to background concentrations of about 2 mg/liter. Magnesium, Na, K, H, and NO3 indicated maximum increases in concentration that averaged two‐ to threefold greater than control values of <0.5 mg/liter. NH4 and TOTAL‐P were unchanged. At 45 cm or in the B23 horizon just above a fragipan, the increases in ionic concentrations following the heavy application were less than one‐half the increases that occurred at 20 cm. The concentrations of most ions returned to background levels within 1 year after sludge application. From the time sludge was applied in June 1975 until the end of the growing season in October 1976, leaching losses for calcium were estimated as 18 kg/ha for the control plots, compared to 39 kg/ha from plots receiving the heavy application. Comparable estimates for SO4 were 35 kg/ha for the control plots and 64 kg/ha for plots receiving the heavy sludge application.

There were no significant differences in basal‐area growth among control and treated plots for the first two growing seasons after sludge application. In the herb and shrub layer only 3 of the 31 commonly occurring species showed statistically significant changes in frequency. All three changes were on plots receiving the heavy application. Sugar maple (Acer saccharum F.) seedlings declined from an average of 22/m2 before application to 17/m2 in the second summer after application. The shrub Viburnum alnifolium Marsh, increased from an average of 5/m2 before application to 11/m2 after and the herb Viola pallens Brainerd increased from 15/m2 before to 21/m2 after.
Decomposition of Sewage Sludge Compost in Soil: III. Carbon, Nitrogen, and Phosphorus Transformations in Different Sized Fractions
Authors: Tester C. F. , Sikora L. J. , Taylor J. M. , Parr J. F.
Published: July 2010

A laboratory incubation study was conducted to determine the rate and extent of decomposition of sewage sludge compost in soil amended with compost fractions of various particle sizes. Cured compost was passed through a 6‐mm screen and further fractionated with a 1‐mm sieve. The three fractions of compost (<6 mm, 1 to 6 mm, and <1 mm) were mixed with a loamy sand at a rate of 89.6 metric tons/ha (dry wt) and incubated at 25°C. Rates of mineralization and decomposition were determined by monitoring CO2 and NH3 evolution and measuring changes in the organic and inorganic fractions of C, N, and P with time. A lime‐treated soil was included as an appropriate control because the compost was produced from a lime‐stabilized undigested (raw) sewage sludge.

Decomposition of the three compost fractions, as determined by CO2 evolution, was directly related to the amount of carbon in the compost‐soil mixtures. Cumulative CO2 evolution was lowest from the compost that passed the 1‐mm sieve and had the lowest C/N ratio. Approximately 8% of the compost C from all fractions evolved as CO2 in 45 days of incubation. The quantity of N mineralized ranged from 3 to 13% for the different fractions, and the extent of N mineralization was inversely related to the C/N ratio. Ammonia evolution paralleled N mineralization in these mixtures. The amount of extractable P was nearly the same for all fractions and did not change during incubation. Although the <1‐mm fraction contained a greater amount of total P than the other two fractions, it contained a smaller amount of extractable P. When the pH was adjusted to 6.6, decomposition of the native soil C increased 82%, but neither soil N mineralization nor the amount of extractable P was affected.
Long‐Term Persistence of Picloram in a Sandy Loam Soil
Authors: Fryer J. D. , Smith P. D. , Ludwig J. W.
Published: July 2010

Picloram (4‐amino‐3,5,6‐trichoropicolinic acid) was applied to a ryegrass (Lolium perenne L. cv S23) sward at 0.05, 0.28, and 1.68 kg ai (active ingredient)/ha in June 1967 and again in August of 1969 and 1970. Small amounts of residue were found in soil samples 1 year after application of the low and medium doses. On the highest dose plots 5 to 6% of the amount applied was usually recovered 1 year after spraying. Following the final application this residue degraded slowly over the following 3 years. Analyses of the final samples (taken 222 weeks after spraying) indicated that the residue had declined to about 0.5% of the total amount applied. In stratified soil samples, residues were found to the maximum sample depth of 90 cm 1 year after the initial application, but 69 weeks after the final application no residue was found below 30 cm.

Crops grown across all plots in 1974 did not differ in yield. However, on the plots that had received the highest dose, leaf abnormalities were noted in beans and potatoes and color differences were observed in kale.
Denitrifying Bacteria Populations and Nitrogen Removal in Soil Columns Intermittently Flooded with Secondary Sewage Effluent
Authors: Gilbert R. G. , Lance J. C. , Miller J. B.
Published: July 2010

The effects of infiltration rates and carbon treatments on denitrifying bacteria populations and N‐removal in soil columns intermittently flooded with secondary sewage effluent (SSE) were determined. At low infiltration rates of 10 to 15 cm/day, N‐removal by denitrification was >80% and enrichment of the SSE with organic carbon did not further enhance N loss, even though the denitrifying bacteria populations were increased. However, at higher infiltration rates (15 to 40 cm/day), the physiologically active denitrifying bacteria populations were effective in net N‐removal, and carbon enrichment of the SSE was essential for maintaining >80% N‐removal. Continuous carbon treatments were more effective than 2‐day pulse treatments for increasing the numbers of denitrifying bacteria and N‐removal. With continuous carbon treatments of 200 mg/liter, >80% N‐removal was obtained at infiltration rates of 40 cm/day. These results indicated that the activity of denitrifying bacteria and the N‐removal capacity of high‐rate land treatment systems could be enhanced by the timely additions of organic carbon to the SSE applied to the soil infiltration basins.
Emergence and Growth of Plant Species in Coal Mine Soil
Authors: Day A. D. , Mitchell G. F. , Tucker T. C. , Thames J. L.
Published: July 2010

Experiments were conducted in the laboratory and greenhouse in Arizona with the following objectives: (i) to evaluate the chemical properties of undisturbed soil, surface‐mined coal land (coal mine soil) on the Black Mesa Coal Mine, and Gila loam soil; and (ii) to study the emergence of seven plant species in the greenhouse in Gila loam soil and coal mine soil. The pH of coal mine soil (6.2) was lower than the pH of undisturbed soil (7.5) or Gila loam (7.6). The total soluble salts in coal mine soil (3,241) and undisturbed soil (4,592) were much higher than in Gila loam (378); however, coal mine soil was lower in total soluble salts than undisturbed soil. The nitrogen content of coal mine soil was higher than the nitrogen content of undisturbed soil or Gila loam. Emergence percentages for seven plant species grown in coal mine soil were similar to emergence percentages for the same species grown in Gila loam. Alfalfa (Medicago sativa L.), barley (Hordeum vulgare L.), and wheat (Triticum aestivum L. em Thell.) had from 84 to 93% emergence in coal mine soil. Indian ricegrass (Oryzopsis hymenoides Roem. & Shult.), fourwing saltbush (Atriplex canescens Pursh.), yellow sweetclover (Melilotus officinalis Lam.), and winterfat (Euroti lanata Pursh.) emerged <35% in coal mine soil and Gila loam. Plant growth data from forage species grown in the greenhouse indicate that coal mine soil has a lower fertility level than does Gila loam soil. When supplied with optimum soil moisture and plant nutrients, coal mine soil produced approximately the same yields of forage from alfalfa, barley, and wheat as were produced in Gila loam under the same soil‐moisture and fertility conditions.
Consequences of Water Movement in Macropores
Authors: Thomas Grant W. , Phillips Ronald E.
Published: July 2010

Current views of infiltration of water into soils are based on nearly complete displacement of soil water by incoming water. In general, rapid flow down macropores and its effect on water and solute distribution have not been considered very important by the majority of researchers. We present evidence to show that flow of water through macropores is important in soil and ground water recharge and in salt movement through soils.
Changes in Concentrations of Selected Chemical Pollutants in Wet, Tile‐drained Soil Systems as Influenced by Disposal of Septic Tank Effluents
Authors: Reneau R. B.
Published: July 2010

Changes in P, MBAS, NH4, NO3, NO2, Cl, pH, and Eh from septic effluent disposal were monitored in shallow ground waters between septic effluent disposal fields and an agricultural tile drainage system in an area composed of Typic and Aeric Ochraquults.

As effluent moved through the soil system toward the agricultural tile, P and MBAS decreased logarithmically with distance. As much as 87% of the observed variation could be attributed to distance for both P and MBAS. Phosphorus and MBAS in ground waters intercepted by the tile drainage system at two of the sites had been reduced to acceptable levels. At location 1 (Typic Ochraquult), P and MBAS moved further (12 m) than might be predicted and were present in ground waters intercepted by the agricultural tile. These concentrations of P and MBAS in waters intercepted by the tile at location 1 resulted from rapid movement of effluent via saturated flow through the larger soil pores and from an inadequate soil volume for effluent purification.

The concentrations of inorganic nitrogenous components in relation to the disposal area were similar at all three locations. The NH4‐N concentration was highest adjacent to the drainfield (20–30 µg/ml) and decreased logarithmically with distance. A maximum of 83% of the observed decrease in NH4 could be attributed to distance. The NO3 concentration increased to a maximum at approximately 5 m and then decreased with increased distance. This was substantiated by the NO3/Cl ratios which indicated that NH4 was nitrified and the NO3 produced was subsequently denitrified to a large degree. The NO3 accumulation was seasonal with the highest concentrations present during periods of rising water tables.
Effects of Liming an Acid Soil Amended with Sewage Sludge Enriched with Cd, Cu, Ni, and Zn on Yield and Cd Content of Wheat Grain
Authors: Bingham F. T. , Page A. L. , Mitchell G. A. , Strong J. E.
Published: July 2010

An acid soil (pH 5.2) was treated ± lime and 1% sewage sludge enriched with three concentrations each of Cd, Zn, Cu, and Ni in a 34 complete factorial design experiment (81 treatments ± lime). These treated soils were placed in pots and cropped with wheat (Triticum aestivum L.). Analysis of variance revealed significant main effects on grain yield from all metal additions to the acid soil and from Cd and Cu only in the limed soil. Significant main effects on the concentration of Cd in grain occurred with all metals added in the limed soil, but only from Cd, Zn, and Ni on the acid soil. Significant multiple metal interactions occurred in all cases. Multiple regression equations were developed for estimating grain yield and Cd content from soil metal additions and saturation extract metal content. Grain Cd concentrations were highly correlated with soil metal additions (R2 = 0.978 and 0.988 for limed and unlimed soils, respectively) and saturation extract metals (R2 = 0.879 and 0.950 for limed and unlimed soils). The best fit equations were used to calculate metal equivalent values for soil metals added (SME) which were then used to develop regression equations and graphs relating grain yield to SME.
Soil Temperature Effects on Uptake of Cadmium and Zinc by Vegetables Grown on Sludge‐amended Soil
Authors: Giordano P. M. , Mays D. A. , Behel A. D.
Published: July 2010

The effects of soil temperature on the uptake of heavy metals by plants grown on sludge‐amended soil has not been established. A field experiment was initiated in 1975 to determine uptake of Cd and Zn by several vegetables from Sango sil amended with 224 metric tons/ha of an anaerobically digested sewage sludge. A variety of commonly grown garden vegetables was selected since many home gardeners have been utilizing digested sewage for its nutrient and soil conditioning value. Soils were heated to approximately 27°C using thermostatically controlled resistance cables placed 30 cm deep and 30 cm apart in the soil. Crops were grown in 1975, 1976, and 1977 to measure Immediate and residual uptake of heavy metals in edible plant parts.

Concentrations of DTPA‐extractable metals in soil increased from 1975 to 1977, but these increases were not reflected in higher plant concentrations. Soil heating significantly increased Cd and Zn concentrations in broccoli and potato; concentrations of Cd and Zn were higher in several other vegetables with heating but differences were not statistically significant. Liming reduced the concentration of Zn and Cd in the crops, but dilution due to better growth may have accounted for a part of the reduction. Analyses of soil cores taken after cropping in 1977 indicated movement of Zn and Cd to a maximum depth of 20 to 30 cm.
Residual Effects of Dairy Cattle Manure on Millet and Rye Forage and Soil Properties
Authors: Mugwira L. M.
Published: July 2010

Dairy cattle manure was applied to plots on Decatur silty clay loam (Thermic Rhodic Paleudults) in 1971, 1972, and 1973. The manure rates were 0, 22.5, 45, 90, 180, and 270 metric tons/ha (dry wt). Pearl millet (Pennisetum americanum, L. K. Schum) was grown in summer and clipped twice and ‘Wrens Abruzzi’ rye (Secale cereale L.) was grown in winter. The residual effects of the manure treatments on forage yields and mineral composition evaluated in 1974, 1975, and 1976 are reported in this study.

The residuals of three annual applications of 180 and 270 metric tons/ha of manure were more effective than the lower rates in increasing millet and rye forage yields in 1974 to 1976 and total N and NO3‐N in 1974 and 1975. Phosphorus and, to some extent, Zn levels in millet were increased by the 22.5‐ and 45‐metric ton rates, leveling or decreasing at higher manure rates. The manure residuals also increased the levels of K in 1974 and, generally, Mg in millet and K and Ca in rye and decreased Mn in millet and rye.

Plant and soil data suggested that N limited plant growth in manured plots except at the 180‐ and 270.metric ton rates. At the higher rates there was significantly higher nitrate movement down the profile than the NPK check. The NO3‐N and total N levels in forage also suggested that N mineralization from three consecutive annual manure applications of 22.5 metric tons/ha was largely completed within the following 3 years.
Age‐dependent Growth and Injury Responses of Pinto Bean Leaves to Gaseous Hydrogen Chloride
Authors: Endress A. G. , Oshima R. J. , Taylor O. C.
Published: July 2010

Susceptibility of unifoliate leaves of Phaseolus vulgaris L. to visible injury following acute exposures to anhydrous hydrogen chloride gas (HCl) and the relationship of susceptibility to leaf age and subsequent growth were examined. Plants varying in age from 6 to 12 days postseeding were treated with 25.6 ± 3.3 mg HCl m−3 for 20 min. Foliar injury consisted primarily of abaxial glazing and bifacial interveinal necrosis. Plants that were 6 days old at the time of exposure were uninjured; the percent of injured unifoliate leaves increased with tissue age at the time of HCl treatment. The relationship was sigmoidal and probit analysis indicated that the estimated stage of maturity at which 50% of the unifoliate leaves became injured (EM90) was 9 days. The rate of leaf expansion between control and fumigated leaves did not differ significantly, but expansion of the fumigated leaves was significantly delayed. The delay was apparently not directly related to visible foliar injury, nor were any differences in the relationship of leaf fresh weight to dry weight noted between control and HCl‐treated leaves.
Tritium in Plants
Authors: Mc Farlane James C. , Beckert Werner F. , Brown Kenneth W.
Published: July 2010

This is a review of literature regarding the fate and consequence of tritium in plants. Concepts and terminologies commonly used in plant‐water relations are generally adequate to describe tritium kinetics in plants. Isotopic fractionation between tritium and stable hydrogen occurs in many plant‐mediated processes and may result in about a 20% depletion in plant organics. Possible errors in tritium studies result from hydrogen exchange and fractionation during sample collection, storage, preparation, and analysis. Potential pitfalls encountered in laboratory and field studies are pointed out and illustrated. Original research data are used to illustrate specific processes.
Atrazine Metabolism in Box Crabs
Authors: Pillai P. , Weete J. D. , Diner A. M. , Davis D. E.
Published: July 2010

The metabolism of atrazine [2‐chloro‐4‐(ethylamino)‐6‐(isopropylamino)‐s‐triazine] in box crabs (Sesarma cinereum) was determined. Leaves of smooth cordgrass (Spartina alterniflora Loisel) collected from plants grown for 2 days in nutrient solution containing [14Cl atrazine, followed by 3 days in an atrazine‐free nutrient solution, were fed to box crabs for 10 days. No significant effects of atrazine on the behavior or survival of crabs were found. At the end of the 10‐day feeding period, crabs and their feces were extracted with 80% methanol, and the extracts were concentrated and partitioned with chloroform. Radioactivities in the chloroform, aqueous, and 80% methanol‐insoluble fractions (remaining crab material) of the extract were 7, 86, and 7% for crabs and 25, 51, and 24% for feces, respectively. Only 1.2 and 0.5% of the total radioactivity in the crab and feces, respectively, was atrazine, compared to the S. alterniflora used as a food source that contained 24% atrazine. This indicates that atrazine is metabolized in the crab. The accumulation of water‐soluble metabolites in the crab suggests that, as in other animals, glutathione conjugation or a comparable pathway is responsible for the almost complete degradation and detoxification of atrazine in these organisms.