bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

AbstractSoil 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

AbstractSelective 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

AbstractDewatered 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

AbstractA 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

AbstractPicloram (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

AbstractThe 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

AbstractExperiments 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

AbstractCurrent 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

AbstractChanges 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

AbstractAn 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

AbstractThe 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

AbstractDairy 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

AbstractSusceptibility 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

AbstractThis 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

AbstractThe 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.