bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Predictive Model for the Accumulation of Cadmium by Container‐Grown Plants
Authors: Browne C. L. , Wong Y.‐M. , Buhler D. R. 
Published: July 2010

AbstractResearch into the dietary availability of Cd, a toxic heavy metal, called for prediction of Cd accumulation by edible crop species to be grown to maturity under greenhouse conditions. Examination of the literature revealed that Cd accumulation in plants grown under greenhouse and oxic conditions could be generally described, with high correlation, by the equation:
urn:x-wiley:15391663:jeq2jeq198400472425001300020002x:equation:jeq2jeq198400472425001300020002x-math-0001 where P is plant Cd (µg Cd/g dry wt), CdDTPA is the DTPA (diethylenetriaminepentaacetic acid) extract estimate of available soil Cd (µg Cd/g soil), and α and β are linear regression coefficients. Published data were fitted to the above equation to determine whether the model coefficients exhibited consistent relationships that would predictably account for the potential effect of soil type, species, and experimental conditions on the accumulation of Cd by plants. For a given experimental situation, β was found to be principally a function of soil pH and cation exchange capacity (CEC), and a single mean value was deemed appropriate for all species. The coefficient α was mainly a characteristic of plant species, and the relative magnitude of the difference among species in the value of α tended to remain constant for differing experimental conditions. Assuming that such a relationship was common to greenhouse crops, estimates of α for several species to be grown under our conditions were derived from the literature. This was accomplished by comparison with values of µ for test crops of spinach (Spinacia oleracea L.) and lettuce (Lactuca sativa L.) grown under our conditions. Substitution of estimated values of α and β into the above equation permitted the successful prediction of soil Cd additions (0.5–15 µg Cd/g) necessary to achieve a specified level Cd in the range of crop species subsequently grown to maturity.
The Relationship Between Adsorption of Trace Metals, Organic Matter, and pH in Temperate Soils
Authors: Gerritse R. G. , van Driel W. 
Published: July 2010

AbstractDistribution constants for Cd and Pb were measured for 33 temperate soils. The distribution constants were related to soil organic matter and pH at three different ionic strengths of soil extractants. The soil extractants consisted of solutions of CaCl2, NaCl, and KCl and were taken to be representative of the composition of the soil solution phases. For each ionic strength a significant log‐log correlation was found between the distribution constants, related to organic matter content of the soil and the hydrogen ion concentrations of the soil extracts. Exchangeable or mobile fractions of Cd and Pb in the soil were calculated from the product of distribution constant and concentration in a soil extract. With the aid of adsorption data of previous work with other soils, assuming a similar relationship as found for Cd and Pb, comparable results were obtained for Cu and Zn. Exchangeable fractions were found to lie in a range of about 1 to 5% of total metal in the soils for Pb and about 10 to 50% for Cd, Zn, and Cu.
Responses of Soil Biota to Organic Amendments in Stripmine Spoils in Northwestern New Mexico
Authors: Elkins Ned Z. , Parker Lawrence W. , Aldon Earl , Whitford W. G. 
Published: July 2010

AbstractWe examined the effects of organic amendments and topsoiling on the soil biota and decomposition in order to evaluate the relative efficacy of the amendments in restarting soil processes. We studied decomposition of barley straw (Hordeum vulgare) and populations of soil biota on strip coal‐mine spoils in northwestern New Mexico. The spoils had been amended with straw mulch, bark, topsoil, or no organic additives. Decomposition rates were highest in the unmined area and the bark, amended spoils (K = 0.64 yr−1) (K = first‐order rate constant), and lowest on the topsoil amendment and unamended spoil (K = 0.34 yr−1). Few differences were observed in the populations of soil microflora. Where differences were observed, the bark‐amended spoils had the highest populations and biomass. Soil microflora activity, as indicated by decomposition rates, was enhanced by bark amendment. Soil microfaunal populations were highest on the bark‐amended spoils and unmined soil. Important soil mites (soil Acari), the oribatids, were found only in the bark‐amended spoils and the unmined soils. These studies suggest that addition of selected organic amendments (bark) to mine spoils may be as effective in developing a soil as the more expensive topsoil/mulch procedures currently used in reclamation procedures.
Potential Aquifer Pollution from Nitrate Leaching Following the Plowing of Temporary Grassland
Authors: Cameron K. C. , Wild A. 
Published: July 2010

AbstractAn investigation of the amounts and concentrations of nitrate released following the plowing of temporary grassland confirmed that, potentially at least, this practice forms a major source of NO3‐N pollution of aquifers. Direct measurements of changes in profile NO3‐N distributions at two sites show that a total of up to about 100 kg N ha−1 was leached over two winters after fall mineralization following plowing. Solution nitrate concentrations were in excess of the World Health Organization limits for drinking water. The amount of N mineralized was related to the total soil N. The average rate of leaching through the Chalk soils studied in southern England was about 1 m/yr.
Nutrient Trapping by Sediment Deposition in a Seasonally Flooded Lakeside Wetland
Authors: Johnston C. A. , Bubenzer G. D. , Lee G. B. , Madison F. W. , Mc Henry J. R. 
Published: July 2010

AbstractSediment and nutrient retention was studied in a seasonally flooded lakeside wetland as a natural mechanism for preventing water quality deterioration. Both wetland and upland soils in the watershed had comparable concentrations of inorganic P on a per‐volume basis, while NH4+‐N and organic forms of N and P were much higher in the wetland soils. Nitrate concentrations expressed in a per‐volume basis were lower in the wetland soils than in the upland soils.The distribution of sediment and nutrients in the wetland was correlated with distance from a small stream flowing through the wetland. Deposition patterns were affected by recent stream channel migrations.The accumulation of nutrients and sediment delivered from the upland to wetland soils was estimated in two ways: (i) by calculating the volume of alluvium deposited in low natural levees adjacent to the stream; and (ii) by estimating nutrient and ash enrichment of histic surface soils farther away from the stream. Although the levees constituted only about 20% of the wetland surface area, they accounted for 81% of the sediment, 84% of the N, and 67% of the P retained by the wetland.The depth of Cs‐137 in the soil was used to estimate net sedimentation rates. Average annual accumulations over the wetland as a whole were: 2.0 kg sediment m−2 yr−1, 2.6 g P m−2 yr−1, and 12.8 N g m−2 yr−1. Since these values exceed those published for average annual storage by wetland plants, soil mechanisms are more important than vegetative uptake for long‐term nutrient and sediment retention in the White Clay Lake wetland.
Prediction of Phosphate Movement Through Some Selected Soils
Authors: Stuanes Arne O. , Enfield Carl G. 
Published: July 2010

AbstractThe P sorption capacity of soils must be evaluated at land application wastewater sites when water quality criteria control the design of the treatment system. The soil's capacity to react with P is often underestimated when equilibrium isotherms are used to describe P sorption. An analytical one‐dimensional convective dispersive solute transport model, assuming linear sorption and first‐order irreversible precipitation, was evaluated to describe the movement of P in small laboratory columns. The model was calibrated to experimental data using nonlinear least squares analysis. The length of the column did not make a significant difference in the model coefficients. This finding suggests that the approximation of a linear sorption isotherm with first‐order irreversible precipitation is adequate for making environmental assessments at land‐treatment systems. Application of the model to the design of a land‐treatment system would permit approximating a system life considering wastewater application rate, concentration of P in the applied water, and travel distance through the soil profile prior to discharge. Experimental data fit to a Langmuir equation using the same soils were found to seriously underestimate the capacity of soil to react with P. The same data fit to a Freundlich or other equilibrium isotherm would yield similar results. It was concluded that use of equilibrium isotherms without considering the kinetics of the reactions will lead to overly conservative designs of land application of wastewater treatment systems.
Elements Associated with the Cadmium Phase in a Harbor Sediment as Determined with the Electron Beam Microprobe
Authors: Lee F. Y. , Kittrick J. A. 
Published: July 2010

AbstractA heavy metal‐contaminated harbor sediment was examined with the electron beam microprobe in order to obtain specific information with regard to the elements associated with the Cd phase(s). Approximately 4.4 × 104 particles were scanned in order to locate 18 that produced > 100 counts/s Cd Kα X‐radiation. Of these Cd‐rich particles, 72% were < 10 µm in diameter. For these particles, Cd was most frequently associated with S (in ca. 89% of the particles, presumably as S2−), rather than with the carbonate indicated by a chemical extraction method on the whole soil. Zinc was also significantly associated with Cd (in ca. 72% of the particles). Cadmium appeared to be precipitated with the associated elements rather than being adsorbed on the surfaces of the selected 18 particles. The formation of Cd sulfides in the sediment can be predicted from thermodynamic calculations, combined with a few reasonable assumptions.
Organic Pollutants in Leachates from Landfill Sites
Authors: Sawhney B. L. , Kozloski R. P. 
Published: July 2010

AbstractGrowing concern for groundwater pollution with potentially hazardous organic chemicals from waste disposal sites prompted this investigation of determining organic pollutants in leachates from a number of municipal landfill sites. Identification of the various compounds was attained using multicolumn GC and GC/MS (gas chromatography/mass spectrometry) techniques. Volatile compounds were concentrated using purge and trap technique and nonvolatile compounds were fractionated into the alkali and acid extracts. Quantitative determinations were made by comparing heights or areas of the GC peaks obtained from the test samples to the corresponding peaks from the standard compounds. Different volatile compounds identified in leachates from landfill sites varied over a wide concentration range. Determinations of volatile compounds in leachates from the Southington, CT landfill site showed large concentrations of some common industrial solvents such as acetone and methyl ethyl ketone. Presence of as high as 4 mg/L of phenols which are readily sorbed and transformed by soils and clays under laboratory conditions suggest that anaerobic landfill conditions may facilitate the movement of phenols and other organic compounds.
Uptake by Plants and Migration of Uranium and Chromium in Field Lysimeters
Authors: Sheppard Marsha I. , Sheppard S. C. , Thibault D. H. 
Published: July 2010

AbstractPlant growth, plant uptake, and the redistribution in soil of U and Cr were studied in field lysimeters. The objective of the experiment was to characterize the plant uptake and migration in the soil of U and Cr when placed at different depths in the unsaturated soil zone within the influence of a water table. Lysimeters with and without vegetation were studied and two soils, and two plant species were investigated.Total uptake of Cr by the plants was directly proportional to Cr concentration in the soil, over eight orders of magnitude. Thus, independent of the amount of Cr applied, the plant took up a similar fraction, about 0.007. Chromium placement depth in the soil did not influence Cr uptake by the plants although the Cr was relatively immobile in both soils.Plant uptake of U was independent of plant species and U placement depth for loam soil, but highly dependent on placement depth in sandy soil. In the latter, much more U was taken up by the plants when it ws placed near the soil surface, implying that uptake was dependent upon root activity. Migration of U from the contaminant band was substantial only in the sandy soil.
Molybdenum Enrichment of Plants Grown on Fly Ash‐Treated Soils
Authors: Elseewi A. A. , Page A. L. 
Published: July 2010

AbstractAlfalfa, bermudagrass, white clover, barley, and Swiss chard (Medicago sativa L., Cynodon dactylon L., Trifolium repens L., Hordeum vulgare L., and Beta vulgaris L., respectively) were grown on calcareous and acid soils treated with fly ash at rates ranging up to 80 g kg−1. The objectives were to investigate the availability of Mo to crops in relation to rate of fly ash application, type of recipient soil, and time of harvest. Application of fly ash to soil resulted in marked enrichment in plant Mo, especially at rates ≥ 40 g kg−1. Except for white clover, Mo concentrations in plants grown on the calcareous soil were greater than those in plants grown on the acid soil. Comparison between Mo concentration in early‐ and late‐season clippings of alfalfa and white clover and in plants grown sequentially indicated the presence of a relatively long‐term supply of Mo in fly ash. It is concluded that in situations where soils are deficient in Mo, plants may benefit from small applications of fly ash to soils, but Mo concentrations in plants grown on fly ash‐treated soils should always be carefully monitored.
Power Plant Influences on Bulk Precipitation, Throughfall, and Stemflow Nutrient Inputs
Authors: Kelly J. M. 
Published: July 2010

AbstractInputs of SO42−, total N, PO43−, K, Ca, and Mg via bulk precipitation, throughfall, and stemflow have been investigated over a 3‐yr period at two forest study sites on the Cumberland Plateau of Tennessee. The Cross Creek Watershed located 19 km from the Widows Creek coal‐fired power plant was used to represent inputs to a forest site in the immediate vicinity of a large emissions source. The Camp Branch Watershed having similar forest cover and soil types, but located in an area 99 and 76 km from the nearest major point sources, was used to represent inputs as a function of regional conditions. Location exhibited its greatest influence on stemflow inputs, with only PO43− and K failing to exhibit a statistically significant (P = 0.05) increase in stemflow input at Cross Creek relative to Camp Branch. Although throughfall SO42−, K, Ca, and Mg input values were higher at Cross Creek, they were not significantly higher than the Camp Branch values. Nitrogen and phosphate throughfall input values were lower at Cross Creek than Camp Branch, but again lacked statistical significance. Nitrogen and phosphate in bulk precipitation were significantly elevated at Cross Creek while other elements and compounds did not respond to location. Based on this evaluation most atmospheric contributions to bulk precipitation, throughfall, and stemflow elemental inputs appear to be of regional rather than local origin.
Mined Land Reclamation Using Polluted Urban Navigable Waterway Sediments: I. Trace Metals
Authors: Van Luik A. 
Published: July 2010

AbstractAs part of a study assessing the suitability of sediments from the Calumet‐Sag Channel, Illinois (Cal‐Sag), for use as a mined land reclamation medium, the concentrations of 11 trace metals were determined in 34 sediment samples representing 10 cores. The cores were taken at 2.4‐km intervals along the length of the Cal‐Sag using a gravity corer. The cores (107 to 173 cm in length) were divided into sections representing approximately 30 to 50 cm of core depth each. Each of these sections was sampled by compositing a sample from along its length. Silt and clay content were determined in addition to the concentrations of the 11 trace metals. Trends in the metal concentration data suggested that As and Hg had a different source and/or history in the Cal‐Sag sediments than Ba, Cd, Cr, Cu, Pb, and Zn. Nickel, selenium, and silver levels were determined for 10 of the samples. Implications of trace metal levels in terms of using Cal‐Sag sediments as a plant‐growth medium in mined land reclamation are discussed. Zinc levels may preclude use of Cal‐Sag sediments for the production of some specific Zn‐sensitive agronomic crops and may require longterm monitoring after placement in productive use to allow management of potential Zn phytotoxicity. Mean total trace metal concentration values for this Cal‐Sag sediment sampling were (mg/kg): As, 19; Ba, 320; Cd, 9.4; Cr, 110; Cu, 120; Pb, 510; Hg, < 0.42; Ni, 38; Se, 0.10; Ag, 4.9; and Zn, 2580.
Mined Land Reclamation Using Polluted Urban Navigable Waterway Sediments: II. Organics
Authors: Van Luik A. 
Published: July 2010

AbstractMaintenance dredging potentially produces an estimated 15 000 m3 of sedimentary material from the Calumet‐Sag Channel (Cal‐Sag) annually. To determine the suitability of this dredged material for use in the reclamation of abandoned mined lands, 10 sediment samples were taken at 2.4‐km intervals along the length of the Cal‐Sag using a gravity corer. Sediment cores (107 to 173 cm in length) were subdivided to represent 40‐ to 50‐cm depth increments, and composite samples were taken along the length of each subsample. Organic pollutant concentrations as well as silt and clay contents were determined. No significant correlations existed between each organic pollutant concentration and sediment sample depths, locations, or sediment silt or clay content. This result suggested that the mean and the mean plus twice the standard deviation offered good approximations of the expected mean value and the expected (95%) maximum value for these pollutants in Cal‐Sag dredged material (volatile solids: 9.85 and 13.1 mg/kg; oil and grease: 11.9 and 22.7 g/kg; total phenols: < 2.4 and < 4.8 mg/kg; and total polychlorinated biphenyls (PCB's): 7.0 and 17 mg/kg). Polycyclic aromatic hydrocarbon (PAH) levels were determined for nine selected Cal‐Sag sediment samples. Measured parent PAH compound levels (46 compounds) exceeded 80 mg/kg in only one sample. Alkyl‐substituted PAH compound concentrations were measured for three parent compounds in three sediment samples and found to be highly variable in concentration (∼ 1 – ∼ 500 mg/kg).
Leaching of Atrazine in the Root Zone of an Alluvial Soil in Nebraska
Authors: Wehtje G. , Mielke L. N. , Leavitt J. R. C. , Schepers J. S. 
Published: July 2010

AbstractLeaching of atrazine [2‐chloro‐4‐(ethylamino)‐6 (isopropylamino‐s‐triazine] was measured from the soil surface to below the root zone in an irrigated field under continuous corn (Zea mays L.). The field was located in the Platte River Valley of central Nebraska in the central Great Plains area of the USA. This nearly level site is typical of the Platte River Valley with a coarse‐ to medium‐textured soil of alluvial origin that contains low levels of organic matter, and with a water table at a 5‐m depth. Vacuum soil water extractors located 1.5 m below the soil surface recovered an average of 0.072% of the atrazine applied to the surface during 1979 and 1980. Analysis of groundwater recovered from wells on opposite ends of the experimental field indicated enrichment with atrazine in the direction of the hydraulic gradient. Results support direct downward leaching as largely responsible for the low‐level atrazine contamination detected in groundwater throughout the irrigated corn production areas of the valley.
Atrazine Dissipation in Conventional‐Till and No‐Till Sorghum
Authors: Ghadiri Hossein , Shea Patrick J. , Wicks Gail A. , Haderlie Lloyd C. 
Published: July 2010

AbstractAtrazine (2‐chloro‐4‐ethylamino‐6‐isopropyl amino‐s‐triazine) dissipation was compared in conventional‐till and no‐till Holdredge loam soil (fine‐silty, mixed, mesic Typic Argiustolls) during the sorghum phase of a 3‐yr winter wheat (Triticum aestivum L.)‐sorghum [Sorghum bicolor (L.) Moench]‐fallow rotation. Dissipation was similar in both tillage treatments and the half‐life of atrazine in the surface 10 cm of soil was estimated by linear regression to be approximately 42 and 50 d in conventional‐till and no‐till plots, respectively. Movement of the herbicide below the upper 10 cm of soil was not significant during the 105‐d sampling period and only traces of atrazine (< 0.05 mg/kg) were found at the 40‐cm depth. Rectangular hyperbola equations were fit to quantitative data and could be used to estimate atrazine levels in the soil profile. Laboratory incubation suggested nonbiological hydrolysis to be the primary means of degradation. Similar atrazine dissipation in conventional‐till and no‐till plots was attributed to the relatively uniform acidity of the soil, which catalyzed atrazine hydrolysis. Long‐term application of NH4NO3 to all plots may have contributed to surface soil acidity and minimized the effect of tillage on atrazine dissipation.
Extractability and Plant Uptake of Trace Elements from Drilling Fluids
Authors: Nelson Darrell W. , Liu Shyilon L. , Sommers Lee E. 
Published: July 2010

AbstractLand disposal of drilling fluids is a common practice following completion of an oil or gas well. Drilling fluids are formulated from components containing a variety of trace elements, but little is known about the bioavailability of these elements following application to soil. A greenhouse study was conducted to determine the yield and trace element content of Swiss chard (Beta vulgaris L.) and ryegrass (Lolium perenne L.) grown in two soils containing 0, 200, or 500 g kg−1 of three water‐based drilling fluids. The drilling fluids differed only in the source of barite (density regulating component). The barites used varied in trace element content. Addition of all drilling fluids increased soil pH, electrical conductivity of saturation extracts (ECsat), and concentrations of total and extractable trace elements. Growth of chard was only depressed by amending soil with the drilling fluid containing high levels of trace elements, while ryegrass growth was reduced with the 500 g kg−1 application rate of all drilling fluids and the 200 g kg−1 application rate of the drilling fluid with high levels of trace elements. Soil analyses suggested that chard and ryegrass yields were likely reduced by high Zn and ECsat, respectively, in drilling fluid‐treated soils. The concentrations of Zn, Cu, Cd, Pb, and As in chard and ryegrass tissues were directly related to total, DTPA‐extractable, and acetic acid‐soluble forms of these elements in soil. The application to soils of drilling fluids prepared from barite containing low concentrations of trace elements resulted in lower levels of trace elements in plant tissues than was obtained with control soils, because drilling fluid additions, increased soil pH and, thereby, decreased metal availability. Similar concentrations of Ba, Hg, and Cr were found in plant tissues grown in control soils and soil‐drilling fluid mixtures. This finding suggests that Ba, Hg, and Cr in drilling fluids are not plant‐available. Trace element availability to plants was similar for the three types of barites studied. Thus, the concentration in plants was a direct function of the amount of trace elements added to soil in the drilling fluids.