bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reevaluation of Partitioning as a Mechanism of Nonionic Chemicals Adsorption in Soils
Authors: Mingelgrin U. , Gerstl Z. 
Published: July 2010

AbstractA critical evaluation of recent suggestions that the adsorption of nonionic organic compounds by soils can be well‐correlated with the partition of the compounds between an aqueous and a nonpolar phase (usually 1‐octanol), or with water solubility is presented. The physical basis proposed for these assumptions is that adsorption of nonionic organic compounds on soil organic matter is a “partition” process between the aqueous phase and a hydrophobic surface phase. The evidence presented in the literature for the dominance of a partition mechanism is insufficient to prove its general applicability. For example, systems in which a distinct hydrophobic phase at the solid surface does not exist are shown to exhibit the uptake behavior presumed to characterize partition. Theoretically, as well as practically, surface uptake cannot be simply defined as “adsorption” or “partition”, but rather there is a continuum of possible interactions starting with fixed site adsorption and ending with true partition between three‐dimensional phases.
Seasonal Disappearance and Volatilization of Toxaphene and DDT from a Cotton Field
Authors: Willis G. H. , Mc Dowell L. L. , Harper L. A. , Southwick L. M. , Smith S. 
Published: July 2010

AbstractVolatilization and subsequent aerial transport is thought to be a major pathway of pesticide disappearance from application sites. Corroborative evidence obtained for agricultural pesticides under field conditions is scarce. The contribution of volatilization to the overall disappearance of toxaphene (chlorinated camphene) and DDT [1,1,1‐trichloro‐2,2‐bis(p‐chlorophenyl)ethane] from cotton (Gossypium hirsutum L.) was studied under field conditions in the “Delta” section of Mississippi. Drought conditions prevailed throughout most of the study. Measurements were made during two periods: (i) a 10.7‐d period after toxaphene was applied by ground equipment to 50‐cm‐tall cotton plants, and (ii) a 32.7‐d period after a similar application of a mixture of toxaphene and DDT to the same plants. Variable amounts of pesticide were unaccounted for (toxaphene, 17% first application, 54% second application; DDT, 72%) and were apparently lost during application and the following 3‐h period before sampling of air, soil, and plants was begun. The calculated 50% disappearance times of toxaphene (4.7 d, first application; and 10.8 d second application) and DDT (10.3 d) on plants agreed reasonably well with previously reported values. Pesticide disappearance rates were linear functions of the pesticide loads on the plants. The volatile loss of toxaphene (as quantified by the last four chromatographic peaks) during the 10.7‐d test period after the first application was 17% of the amount intercepted by the plants. The comparable volatile loss during the first 10.7 d after the second application (32.7‐d test period) was 33% of the amount on the plants. Total toxaphene and DDT volatile losses during the complete 32.7‐d test period were 53 and 58% of the amounts on the plants, respectively. Because of dry weather, no measurable pesticide volatilization occurred from soil. Disappearance rate changes, as well as volatilization rate changes, for toxaphene and DDT applied at the same time were approximately equal. The study provides additional evidence that post‐application volatilization from plants is a major pathway of pesticide transport.
Chemistry of Water‐Soluble, Metal‐Complexing Ligands Extracted from an Anaerobically‐Digested Sewage Sludge
Authors: Baham John , Sposito Garrison 
Published: July 2010

AbstractOrganic ligands extracted with deionized water from a representative municipal sewage sludge were studied by a variety of chemical techniques. The use of deionized water as an extractant of soluble organic matter from sewage sludge offered two advantages over NaOH: (i) the water soluble extract (WSE) represents an environmentally significant fraction, and (ii) counterion and inorganic ligand levels are comparable to those in FA extracts that have undergone tedious, extensive purification steps. Approximately 8% of the total sludge C was extracted with H2O. A charge balance calculation, including the major inorganic components of the WSE, yielded a value of 5 molc kg−1, for the cation exchange capacity (CEC) of the extracted organic matter. The molar organic C/N ratio for the WSE was found to be 6, indicating that the mixture is rich in polypeptide, amino sugar, and/or nitrogeneous base‐containing compounds. The presence of amino groups and carbohydrates was confirmed both by infrared (IR) identification and by direct chemical analysis. Amino acids accounted for 25% of the WSE organic carbon (CTS), with polysaccharides, hexosamines, and a steam‐volatile component accounting for 12, 9, 8.5% of the CTS, respectively. In total, 55% of the CTS in the WSE was identified as organic compounds that can form soluble complexes with transition metals. Gel filtration experiments suggested that approximately one‐half of the organic compounds in the WSE have relative molecular masses of < 1,500 daltons. The low molecular mass fraction of the WSE is composed primarily of aliphatic organic acids.
Effects of Surface Treatment and Interplanting of Shrub Alder on Growth of Douglas‐fir on Coal Spoils
Authors: Heilman Paul 
Published: July 2010

AbstractAnnual growth of Douglas‐fir (Pseudotsuga menziesii (Mirb.) Franco) planted on topsoiled spoils at a coal mine near Centralia, Wash., was monitored for the first 5 y after planting. Treatments were contour bedding, contour bedding plus interplanted Sitka alder (Alnus sinuata (Reg.) Rydb.), and unbedded control. The bedding significantly increased growth of Douglas‐fir in all 5 y of the study. Total height growth after 5 y was 35% greater than control on the bedding only plots, and 43% greater on the bedding plus Sitka alder plots. Height growth of Douglas‐fir in the mixed stand was significantly greater during the 2nd and 3rd y of the study, but after 5 y, no significant difference was evident in total height between the mixed and pure Douglas‐fir plots. Concentration of N in Douglas‐fir foliage was significantly increased by bedding in the fifth but not in the fourth year. Interplanting with Sitka alder had no significant effect on N in Douglas‐fir foliage.The top 0.3 m of soil in the ridged portion of the bedded area contained significantly less moisture over a summer than did the top 0.3 m of the unbedded soil. At deeper depths, however, soil moisture was not significantly affected by bedding.Wind damage caused by a severe storm that occurred after 5 y was very much greater on the unbedded plots (49% wind‐thrown vs. 9 to 15% wind‐thrown on the bedded plots) despite the smaller size of the trees on unbedded plots.
Response of Maryland Tobacco to Saline Aerosol Emissions From Brackish Water Cooling Towers
Authors: Mulchi Charles L. , Armbruster J. A. 
Published: July 2010

AbstractField studies were conducted on Maryland tobacco (Nicotiana tabacum L.) for 8 weeks during each summer from 1973 to 1977, to acquire information on the response of tobacco to simulated saline aerosol deposition from brackish water cooling towers. The studies involved two sources of salts (NaCl and brackish water from the Unit 3 cooling tower at Chalk Point, Md.), and various salt deposition rates (0.97 to 22.24 kg ha−1 week−1). Results obtained from these simulated drift studies were compared with results obtained from 12 monitoring sites located at 1.6‐, 4.8‐, and 9.6‐km distances from an operating natural‐draft cooling tower at Chalk Point, Md. over the period 1975 to 1978.No foliar injury symptoms associated with salt deposition were observed in either the simulation drift studies or cooling tower monitoring program during the investigation.In the simulated drift studies, regardless of salt sources or deposition rates, yield, average price, value, quality index, total alkaloid, and total N contents were found to be highly variable and generally non‐significant (p ≤0.05). However, trends for positive increases in yields were observed in four of the five studies at salt deposition rates ≤4.0 kg ha−1 week−1. No yield reductions were observed, even at salt deposition rates equal to 22.24 kg ha−1 week−1.Statistically significant (p ≤0.05) increases in leaf Na and Cl contents, and decreases in metabolic index [MI = (% P + % K + % Ca + % Mg)/(% Na + % Cl)] values and leaf burn duration were observed with increased salt deposition rates in all five studies.In the cooling tower monitoring program, no significant (p ≤0.05) differences were observed for yield, quality, burn, Cl contents or metabollic index value with respect to distances or years × distance interaction; however, year‐to‐year variation was significant. These resuits suggest that the operation of the Unit 3 cooling tower using brackish water was not having a significant impact on tobacco grown in the region.
Boron in Mine Soils and Rehabilitation Plant Species at Selected Surface Coal Mines in Western United States
Authors: Severson R. C. , Gough L. P. 
Published: July 2010

AbstractBoron (B) content in mine soils and plants was assessed at 11 strip mines in the northern Great Plains, Powder River basin, and Green River coal regions. Except for unusually high B levels at one Wyoming mine, B levels in both mine soils and plants indicate that deficiency or toxicity conditions are minimal over this large geographic area. Relationships among mine‐soil pH, organic‐matter content, and hotwater soluble B, and B in plants are typical of those commonly reported in the literature. In addition, electrical conductivity (EC) of a water saturation extract of mine soil was positively correlated with B in mine soils. Regulations that suggest routine analysis for B to determine allowable levels in mine soils and rehabilitation plant species may be simplified. The more common measurements of pH and EC of mine soils should provide sufficient information to indicate potential B problem areas, where plant and mine soil analyses for B could then be performed.
Chemical Elements in Soils Under Cattle Pens
Authors: Dantzman C. L. , Richter M. F. , Martin F. G. 
Published: July 2010

AbstractIn cattle feedlots, the manure builds up and to some extent becomes incorporated into the soil profile through downward leaching and the stirring action created by the cattle. The object of this study was to measure the extent of build‐up of certain chemical elements resulting from the cattle wastes within the soil profile (Felda fine sand) in a cattle feedlot after 10 and 15 y. Soil samples were taken at 15‐cm increments from the soil surface to a depth of 137‐cm. Results indicated most of the increase of elements occurred near the soil surface. Within the soil profiles, the magnitude of increase of the chemical measurements compared with the control profile after 10 and 15 y were as follows, respectively: Mg, 23 and 39 times the amount in the control profile; P, 50 and 95; Ca, 11 and 29; K, 133 and 85; Mn, 4.4 and 9.5; Fe, 1.4 and 1.3; Cu, 2.5 and 4.2; soluble salts, 5.9 and 8.6; and percent organic matter, 1.6 and 5.1 times the amount in the control profile. The range of soil pH values increased from 3.6 to 4.7 for the control; from 7.8 to 9.1 after 10 y, and from 8.3 to 8.7 after 15 y.
Adsorption of Diuron and 2,4,5‐T on Soil Particle‐Size Separates
Authors: Nkedi‐Kizza P. , Rao P. S. C. , Johnson Jennifer W. 
Published: July 2010

AbstractEquilibrium isotherms for the adsorption of herbicides, diuron, and 2,4,5‐T on whole soil and various‐size separates of Webster soil (Typic Haplaquolls) were measured. The Freundlich adsorption coefficient, K, for diuron varied by a factor of about 7 among the different particle‐size fractions. However, the sorption coefficient, K, normalized with respect to soil organic carbon (OC) content, denoted as Koc = (K/OC), varied only within a factor of 1.5. For 2,4,5‐T herbicide, the Koc values for the silt and clay‐size fractions, as well as the whole soil, were essentially identical and about 3 times larger than that for the sand‐size fraction. The results suggested that the soil particle‐size separates may be grouped into two size classes: “fine” (≤ 50 µm) and “coarse” (2,000‐50 µm). For a given pesticide, a specific Koc value may be assigned to each class.
Effects of Dried Sewage Sludge on Barley Genotypes
Authors: Day A. D. , Thompson R. K. , Tucker T. C. 
Published: July 2010

AbstractAn experiment was conducted at Mesa, Ariz. in 1976 and 1977 to compare the growth and grain yield of 16 barley (Hordeum vulgare L.) genotypes when grown with dried sewage sludge and inorganic fertilizers from commercial sources.The genotypes were grown on a Laveen loam soil, which is a member of the coarse‐loamy, mixed, hyperthermic Typic Calciorthids. At planting in December of each year, three fertilizer treatments were applied: (i) recommended rates of N, P, and K for barley in Arizona, (ii) 10 t/ha of dried sewage sludge, and (iii) inorganic fertilizers to provide N, P, and K in amounts equal to those applied in the sewage sludge.Barley genotypes evaluated for vegetative growth and grain yield responded similarly when fertilized with dried sewage sludge and inorganic fertilizers from commercial sources. Regardless of the fertilizer treatments, analysis of variance showed highly significant differences between genotypes. Fertilizer‐genotype interactions did not follow a uniform pattern to make a conclusive ranking of means. Results indicate that dried sewage sludge may be as valuable a fertilizer source as commercial fertilizers. Additional research using various sludge rates may be necessary to investigate the maximum fertilizer response potential of specific barley genotypes for the efficient use of sewage sludge in commercial barley production.
Alfalfa, Sweetcorn, and Wheat Responses to Long‐Term Application of Municipal Waste Water to Cropland
Authors: Campbell W. F. , Miller R. W. , Reynolds J. H. , Schreeg T. M. 
Published: July 2010

AbstractThe objective of this study was to assess, over two growing seasons, the long‐term effects of applying municipal waste water on agricultural land under semi‐arid conditions on selected crops. Alfalfa (Medicago sativa L.) cv Ranger, sweetcorn (Zea mays L.) cv Jubilee, and wheat (Triticum vulgare L.) cv Fremont, were grown on land to which waste water had been applied for > 15 y. Plants grown on effluent‐irrigated sites had greater growth rates, dry weights, and yields than did plants grown on irrigated control sites. Chemical analyses for metals in plant parts showed that Na was higher in plants growing on the waste water site, whereas Cu, Fe, and Zn were much higher in plants harvested on control sites. Metal concentrations observed in plant materials were below hazardous levels reported in the literature. In general, no significant, detrimental, long‐term effects of applying municipal waste water on land under semi‐arid conditions were detected. In fact, available P levels increased in effluent‐irrigated soils.
Elemental Contents of Plants Growing on Soil‐Covered Retorted Shale
Authors: Schwab A. P. , Lindsay W. L. , Smith P. J. 
Published: July 2010

AbstractThe concentrations of several potentially toxic elements (F, B, Mo, Pb, Ni, Co, Cd, Cr, Hg, Se, and As) were determined in plants growing on various depths of soil covering retorted (Paraho) shale. The plants that were sampled include: Indian ricegrass (Oryzopsis hymenoides), fourwing saltbush (Atriplex canescens), western wheatgrass (Agropyron smithii), Sherman's big bluegrass (Poa ampla), Utah sweetvetch (Hedysarum boreale), and winterfat (Ceratoides lanata). The F levels were elevated in some of the plants growing on 30 cm of soil over shale. The concentrations of Mo and the Cu/Mo ratios in the plants indicate that molybdenosis could be expected with livestock grazing on revegetated plants. Increasing the depth of soil cover reduced the Mo levels, but the second year's data indicate that increasing the soil depth may only temporarily reduce the potential molybdenosis problem. The plant levels of Pb, Co, Cd, and Hg were below analytical detection limits. The plant concentrations of Ni, As, Se, B, and Cd were too low to be of environmental concern.
Heavy Metals and Persistent Organics at a Sewage Sludge Disposal Site
Authors: Baxter J. C. , Aguilar M. , Brown K. 
Published: July 2010

AbstractThere are problems associated with the utilization of sewage sludge as an agricultural fertilizer. One of the more pressing problems is the question of heavy metals and persistent organics. There is concern that indiscriminate disposal of sewage sludges on agricultural lands may lead to decreased crop yields, and/or may endanger the human food chain through excessive accumulation of some of these metals in edible portions of crops.The effects of sewage sludge disposal on agricultural land, and possible transmission of sludge contaminants into the food chain is a possible environmental problem. Soils, plants, and sewage sludge from the Metro Denver sewage sludge disposal site were examined for trace elements and persistent organics content. Concentrations of Zn, Cu, Ni, Cd, Pb, and Hg in soils increased when sludge was applied, whereas concentrations of As, Se, Mo, and 22 refractory organics were unaffected. Forage crops grown on these soils showed increased concentrations of Zn, Cu, Cd, and Ni; however, these metals were not elevated to a phytotoxic level or above ranges that would be considered normal for forage tissues. Concentrations of As, Se, and Hg in forage tissues were unchanged, while Pb concentrations decreased as a result of sludge applications. None of the forage tissues examined contained detectable levels of any of the 22 organics that they were analyzed for.Soil metals (Zn, Cu, Ni, Cd, and Pb) extracted with DTPA (diethylenetriaminepentaacetic acid) did not correlate with plant concentrations of these metals. Results indicated that the DTPA soil test could be used as a reliable index as to the total metal concentration of a soil, but not as an indication of heavy metal availability for crop uptake.Heavy metals and P remained within the depth of sludge incorporation. Nitrate concentrations, while decreasing with soil depth, showed that substantial amounts had leached to a 91‐cm depth.
Heavy Metals and Persistent Organics Content in Cattle Exposed to Sewage Sludge
Authors: Baxter J. C. , Johnson D. E. , Kienholz E. W. 
Published: July 2010

AbstractCattle grazing a sewage sludge disposal site were examined to determine whether, and to what extent, contamination of tissues had occurred as a result of exposure to sewage sludge. The heavy metal and persistent organics content of kidney, liver, muscle, and bone tissues from cattle grazing a sewage sludge disposal site were compared with tissues of cattle from a nearby control ranch. Tissues were analyzed for As, Cd, Cu, Hg, Mo, Ni, Pb, Se, Zn, and 22 persistent organics.The sludge‐exposed cattle had an average kidney‐Cd content of 16 mg/kg (dry weight), which was significantly higher than the 4 mg/kg found in the control herd, but was not above a range that would be expected from older range cattle. There were no other tissue differences between the two groups with respect to Cd.The average liver‐Cu concentration (4.6 mg/kg) of the sludge‐exposed cattle was significantly lower than that of the controls (19 mg/kg); however, both groups of animals displayed liver‐Cu concentrations that were considerably lower than levels previously considered normal. Mean kidney‐Hg and liver‐Se concentrations were significantly higher in the control cattle than in the sludge‐exposed cows. Kidney‐Zn concentrations of the sludge‐exposed cattle were significantly higher than those of the controls, but the magnitude of the differences was small. Differences between the two groups of animals in relation to Hg and Se were small, and it is doubtful that any real biological significance can be assigned to these differences.Fat was the only tissue that contained detectable levels of 22 persistent organics. The only significant difference observed was alpha‐BHC (hexachlorocylohexane, alpha); the control herd averaged 30 µg/kg (wet weight), whereas the sludge‐exposed cattle averaged 10 µg/kg.
Hydrology and Soil Loss From a High‐Fertility, Rotational Pasture Program
Authors: Owens L. B. , Van Keuren R. W. , Edwards W. M. 
Published: July 2010

AbstractFive small watersheds (0.25–3.1 ha) on sloping uplands in eastern Ohio were used to evaluate environmental effects of a beef management program of rotational summer grazing on one area, and rotational winter grazing/feeding with stored hay on another area. During the 5‐y study, annual precipitation was 1080 mm, which was 8–15% greater than the long‐term average. The surface runoff was measured by precalibrated H‐flumes, and automatically sampled using Coshocton wheels. Surface runoff from watersheds with beef cattle management increased, compared with the long‐term averages when hay was grown on the watersheds. Greater precipitation was the primary factor causing more runoff during the growing season (May–October), and the cattle management was a major contributing influence on the runoff increase during the dormant season (November–April). Maintenance of good vegetative cover on the study areas was a major factor in limiting annual average surface runoff to < 110 mm, which was a relatively small amount. The large runoff events, although a small percentage of the total number of events, produced most of the runoff volume. Soil loss from these pastures was minimal.
Plant Availability of Heavy Metals in a Sludge‐Treated Soil: I. Effect of Sewage Sludge and Soil pH on the Yield and Chemical Composition of Rape
Authors: Narwal R. P. , Singh B. R. , Panhwar A. R. 
Published: July 2010

AbstractThis study investigated the effects of sewage sludge and soil pH on yield and chemical composition, and heavy metal uptake of fodder rape (Brassica napus L. ‘Kenton’). Plants were grown in the greenhouse on a sandy soil amended with an anaerobically stabilized sewage sludge. Lime needs of the soil to attain pH levels of 5.6, 6.0, and 7.5 were determined in a separate incubation study. The rates of sewage sludge applied were 0, 50, and 100 t/ha on a dry weight basis. Application of sewage sludge in the incubation study decreased the soil pH, and consequently increased the lime needs of the soil. The soil pH also decreased with increasing period of incubation. Plants were harvested 5 weeks after germination, and again 5 weeks after the first harvest. For each harvest, the application of sludge increased the total dry matter yield of rape significantly at all pH levels. Maximum yields were obtained at pH 6.0. The concentrations of all measured macro‐nutrients generally increased with increased rate of sludge, but the concentrations were invariably lowest at pH 6.0.The concentrations of Zn, Cd, and Ni in fodder rape generally increased, and those of Mn, Cu, and Co generally decreased with increased rate of sludge application. The pH level influenced the concentrations of the heavy metals studied, with the exception of Pb. The concentrations generally decreased when the pH increased. Although concentration of heavy metals was higher in the second harvest, in general, total amounts recovered were higher in the first harvest. The recovery of metals in rape, calculated as a percentage of 0.2N HCl‐extractable metals from the soil, decreased as the levels of sludge and soil pH increased.