bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Sewage Sludge Cadmium Concentration on Chemical Extractability and Plant Uptake
Authors: Jing Jung , Logan Terry J. 
Published: July 2010

AbstractSeventeen anaerobically digested sludges of widely varying total Cd contents were used to test the hypothesis that, at a fixed Cd application rate, plant uptake of the metal is proportional to Cd concentration in the sludge. Proof of this hypothesis would support the concept of a “clean” sludge as a mechanism for reducing risk of food‐chain contamination by sludge Cd. The sludges varied in total Cd content from 0.07 to 2.02 mmol/kg. The sludges were extracted with: (i) 0.05 M Ca(NO3)2: (ii) 0.05 M Ca(NO3)2 plus 50 µM Na‐EDTA (ethylene diamine tetraacetate); and (iii) Chelex 100 resin. Total concentrations of Cd and major cations and anions were determined in the equilibrium salt solutions, and the chemical speciation program GEOCHEM was used to calculate Cd2+ activities. Uptake of Cd by sudax [Sorghum bicolor (L.) Moench], a hybrid of sorghum [Sorghum vulgare (L.) Moench] and sudangrass (Sorghum vulgare var. sudanense), was measured in a pot study at constant Cd application rates of 11 and 22 µmol/kg soil. Sudax was seeded into acid‐washed sand in paper pots with bottoms removed and the sand held in place with cheesecloth. After full root development, the pots were placed on similar containers containing 500 g (oven‐dry basis) of Spinks loamy sand (Typic Udipsamment) and grown for 6 wk. The aboveground biomass was weighed and analyzed for Cd. Total Cd (CdT) and Cd2+ in Ca(NO3)2 and Ca(NO3)/EDTA, and resin‐extractable Cd were all correlated positively with each other and with sludge CdT. Plant uptake of Cd was positively correlated with sludge CdT (R2 = 0.33), Ca(NO3)2‐CdT (R2 = 0.91), Ca(NO3)2‐Cd2+ (0.89), Ca(NO3)/EDTA‐CdT (R2 = 0.94), Ca(NO3)/EDTA‐Cd2+ (0.90), and resin‐Cd (R2 = 0.92) Uptake was better correlated with Cd/P ratios in sludge than with Cd content alone. The results of this study support the hypothesis that plant uptake is controlled, in part, by sludge Cd chemistry, specifically sludge Cd content, and suggests that “clean” sludges pose less of a risk to the food chain than more contaminated sludges at equal sludge application rates.
Lead, Cadmium, and Zinc Contamination of Aspen Garden Soils and Vegetation
Authors: Boon D.Y. , Soltanpour P.N. 
Published: July 2010

AbstractSamples of old silver mine dump materials, garden soils contaminated with mine dump materials, noncontaminated garden soils, and vegetation grown in these gardens were collected to determine the extent of Pb, Cd, and Zn contamination in Aspen, CO. Total HNO3‐HCIO4‐HF‐soluble and NH4HCO3‐DTPA (AB‐DTPA)‐extractable metals in mine dump materials and soils, respectively, were determined by inductively coupled plasma atomic emission spectrometry (ICPS). Plant samples were diegested with HNO3 and analyzed by ICPS. Total metals ranged from 135 to 21 700 mg kg−1 Pb, from 13.3 to 223 mg kg−1 Cd, and from 144 to 20 000 mg kg−1 Zn in mine dump materials. The AB‐DTPA‐extractable metals ranged from 9.2 to 808 mg kg−1 Pb, from 0.2 to 14.2 mg kg−1 Cd, and from 8.4 to 484 mg kg−1 Zn in garden soils. Many of the mine dump materials and soils contained sufficient quantities of Pb and Cd to pose potential health risks if the contaminated materials were ingested. Plant tissues were sampled from the above gardens. In general, leafy tissue concentrations of Pb, Cd, and Zn were highest. Root and other tuber crops were intermediate, lower than leaves, but higher than fruits. The range of concentrations of metals in the leafy tissues were from <5.0 to 45 mg kg−1 for Pb, from 0.6 to 11.9 mg kg−1 Cd, and from 16 to 444 mg kg−1 for Zn. In the roots, metals ranged from <5.0 to 12 mg kg−1 Pb, from 0.5 to 3.6 mg kg−1 Cd, and from 19 to 150 mg kg−1 Zn. Vegetable fruits contained <5.0 mg kg−1 Pb, from <0.5 to 2.7 mg kg−1 Cd, and from 46 to 107 mg kg−1 Zn. Members of the species Brassica oleracea did not accumulate Pb in leaves, even when grown on highly contaminated soils, but accumated Cd and Zn. It was concluded that old mine dump materials have contaminated garden soils placed on them with Pb, Cd, and Zn. The contaminated material poses a health hazard, especially for children. These potential health risks caused the USEPA to list the site on the National Priority List (Superfund sites). The USEPAh as completed its REMEDIAL INVESTIGATION/FEASIBILITY STUDY of Aspen mine dumps and has scheduled implementation of remedial action (clean up) to begin in 1991.
Remediation of Gasoline‐Contaminated Soil by Passive Volatilization
Authors: Donaldson Susan G. , Miller Glenn C. , Miller W. W. 
Published: July 2010

AbstractLoss of 10 hydrocarbons characteristic of those found in gasoline (benzene; n‐heptane; toluene; m‐xylene; n‐nonane; n‐propylbenzene; 1,2,4‐trimethylbenzene; n‐butylbenzene; 1,2,4,5‐tetramethylbenzene; and n‐dodecane) from 20‐cm soil layers was investigated in several field experiments. Soil was spiked with 50 mg kg−1 of each compound, placed in pans outdoors, and subjected to one of five treatments: dry, unmixed soil; dry soil mixed weekly; soil watered once only; soil watered periodically; and soil watered and mixed periodically. Significantly greater rates of loss occurred from wet soils, with an average of 5.7% remaining in wet and mixed treatments at the 18‐ to 20‐cm depth on Day 32 of the spring experiment, compared with 61% remaining in dry, unmixed soils. Following wetting of the soil by rain, less than 8% overall remained in any soil layer by Day 64. Loss was greatest during the summer experiment. By Day 32, only tetramethylbenzene and dodecane were measurable for the wet treatments, with totals below 5% at the 18‐ to 20‐cm depth. An average of 48.6% remained in the dry soils. The final experiment during fall 1989 demonstrated loss of 500 mg kg−1 of unleaded gasoline from spiked soil. No measurable amounts remained after 8 d in wet and mixed treatments and 16 d in wet, unmixed treatments, but 3.5% remained after 32 d in initially dry soil. These findings indicate that removal of gasoline from contaminated soils can be significantly accelerated by the addition of water.
Nitrate‐Nitrogen and Phosphate‐Phosphorus in Seven Kentucky Streams Draining Small Agricultural Watersheds: Eighteen Years Later
Authors: Thomas Grant W. , Haszler Gerald R. , Crutchfield James D. 
Published: July 2010

AbstractSeven streams draining agricultural watersheds and representing the agriculturally important physiographic regions of Kentucky were resampled during the months of December 1989 through June 1990. These streams had previously been sampled in 1971–1972. During the intervening 18 yr, the use of fertilizer N in Kentucky has nearly doubled and fertilizer phosphate use has increased slightly. Nevertheless, phosphate contents of these streams averaged somewhat lower than they did 18 yr ago and NO3‐N was almost exactly the same. Only one watershed had changed appreciably in land use; a subdivision had been built and equipped with a sewage plant that drains into one of the creeks. Samples taken above and below the sewage effluent demonstrated the strong effect of the subdivision on both NO3 and PO4 in the water. As indicated 18 yr ago, parent rock of the soils continues to have a greater effect on NO3‐N and PO4 content of streams than does agricultural use.
The Environmental Impact of Bovine Somatotropin Use in Dairy Cattle
Authors: Johnson Donald E. , Ward Gerald M. , Torrent Joan 
Published: July 2010

AbstractThe environmental impact of bovine somatotropin (bST) use in dairy cattle (Bos taurus) was analyzed with the following assumptions: base herd (1989) of 10.1 × 106 cows, milk production 6475 kg of 3.5% fat per 305 d; bST herd of 8.96 × 106 cows, 3.8 kg/d increase during 215 d treatment period; 100% adoption rate, 60 d dry period, 40% replacement rate; all formulated diets from: alfalfa (Medicago sativa L.) hay, corn (Zea mays L.) silage, cracked corn, soybean [Glycine max (L.) Merr.] meal, and supplement to satisfy level of production. Using these assumptions, the analysis indicates that the current U.S. milk supply could be produced by 11% fewer cows fed 9% less feed produced on 6% less land, and soil loss would be 5% less. Fossil fuel requirements would be 6% less and irrigation water use would be reduced by 9%. Output of the greenhouse gas methane would be decreased 9%; manure production and outputs of N and P declined by 10, 8, and 10%, respectively.
Utility and Railway Right‐of‐Way Contaminants in British Columbia: Chlorophenols
Authors: Wan Michael T. 
Published: July 2010

AbstractUtility and railway right‐of‐way ditches flowing to salmon (Oncorhynchus spp.) streams in the Lower Mainland of British Columbia, Canada, were sampled in 1990 to determine the occurrence and levels of chlorophenols (CP). Ditches of pristine watershed areas, parklands, and agricultural lands were also sampled to establish background/reference levels of CP. While CP were not detected in ditches of pristine watershed areas and parklands, they were found in farmland, utility, and railway right‐of‐way ditches. In utility right‐of‐way ditches, CP in water adjacent to treated poles averaged 1408 µg/L, compared to a mean level of 13.6 µg/L 4 m downstream; in sediments collected from the same sites, the mean concentration of CP was respectively 139 mg/kg and 0.3 mg/kg. For railway right‐of‐way ditches, the mean level of CP in water adjacent to treated poles was 225 µg/L, in contrast to 3.8 µg/L 4 m downstream. Chlorophenol levels in ditch sediments of railway right‐of‐way with treated poles averaged 49.7 mg/kg, compared to 0.4 mg/kg in sediments of railway right‐of‐way ditches without treated poles. Soils at the base of utility poles registered a mean CP concentration of 2168 mg/kg, whereas those from railway ties averaged 38.6 mg/kg of CP. Low CP levels were found only in ditch sediments of farmlands. Although the biological implications of CP‐contaminated ditch sediments are not well known, CP levels found in ditch water adjacent to treated poles exceeded the 96‐h LC50 (lethal concentration of a chemical to 50% of the test fish population) of salmonids, while those found downstream were within the range reported harmful to the fish and aquatic invertebrates.
Leaching, Dissipation, and Efficacy of Metolachlor Applied by Chemigation or Conventional Methods
Authors: Barnes C.J. , Lavy T.L. , Talbert R.E. 
Published: July 2010

AbstractField leaching, dissipation, and efficacy of metolachlor (2‐chloro‐N(2‐ethyl‐6‐methylphenyl)‐N‐(methoxy‐1‐methylethyl)acetamide) were evaluated for 8 wk when the herbicide was applied by conventional and chemigation methods to a Taloka silt loam soil (coarse‐silty, mixed, nonacid, thermic Mollic Albaqualf). Laboratory studies were conducted to evaluate adsorption and mobility of the herbicide in five soil depths ranging from 0 to 38 cm. Metolachlor leaching below 30 cm was not observed in either year, regardless of application method. Dissipation rates of metolachlor were not influenced by application method either year. Efficacy of the herbicide was not affected by method of application. Metolachlor sorption was highest in the 0‐ to 8‐cm soil depth of the Taloka silt loam with an organic matter content of 1.1%.
Riparian Afforestation Effects on Water Yields and Water Quality in Pasture Catchments
Authors: Smith Christine M. 
Published: July 2010

AbstractThe flow records for two pasture headwater catchments for 9 yr before, and 9 yr after riparian afforestation in one catchment were compared. Average rainfall was 1021 mm yr−1. Riparian afforestation reduced water yields by 68 to 104 mm (21–55%) when the Pinus radiata stand was 8 to 10 yr old. Delayed runoff declined by 52 to 93 mm yr−1 (27–63%). Afforestation reduced the quickflow yield in 1 yr (22 mm or 40%). Peak flows declined in small events, were not affected in medium‐sized events, and may have increased in large events. The large reductions in yield indicate that the riparian zone had a disproportionately important influence on catchment hydrology. They are attributed to high transpiration losses from the riparian pine in seasons with water deficits, and higher than usual forest interception losses because of the small‐scale planting. Streamwater sediment, total and dissolved N and P concentrations in these two catchments and another riparian afforested catchment were monitored for 2 yr. Concentrations were generally lower in the completely pastured catchment. Estimated annual sediment, total P, Kjeldahl N, and nitrate exports from the pasture catchment were 31 to 60%, 70%, 61 to 64% and 58 to 74% of those from the riparian afforested catchments in spite of a higher water yield. Possible explanations for the poor water quality in riparian afforested catchments are described including the lack of riparian wetlands, in‐stream vegetation, and close riparian ground cover. The consequences of riparian afforestation in pasture catchments may not readily be predicted from the impacts of complete catchment afforestation.
Selenium in Kesterson Reservoir Ephemeral Pools Formed by Groundwater Rise: I. A Field Study
Authors: Tokunaga Tetsu K. , Benson Sally M. 
Published: July 2010

AbstractOne of the principal initial plans for managing Se contamination at Kesterson Reservoir (Merced County, California) entailed excavation to a depth of at least 0.15 m in order to remove soils with Se concentrations higher than 4 mg kg−1. Prior to implementing this plan, surface waters were collected from numerous shallow ephemeral pools that formed during the winters of 1986 to 1988. Elevated concentrations of Se were measured in all of these pools. Pools formed during this period from a combination of overland flow from adjacent nonseleniferous pond waters, rainfall ponding, and emergence of the fluctuating shallow water table above the soil surface. Selenium in these ephemeral pool waters originated primarily from dissolution of surface salt crusts and from displacement of seleniferous soil solutions up to the surface. Through the monitoring of a test plot where 0.30 m of the surface soil had been removed, the potential was demonstrated for shallow water table rise to displace seleniferous soil solutions to the surface, resulting in highly seleniferous ephemeral pools. In the test plot, ephemeral pool Se concentrations often exceeded 103µg L−1. This study clearly demonstrated (i) that pools formed over soils with total Se concentrations in the range of 0.5 to 1.7 mg kg−1 could still provide a highly seleniferous aquatic environment, (ii) that the total Se concentration in a soil can be a misleading parameter to use in determining target goals for remediation, and (iii) that the excavation strategy was inappropriate for the Kesterson Reservoir setting.
Sampling Unsaturated‐Zone Water for Trichloroethene at Picatinny Arsenal, New Jersey
Authors: Smith James A. , Cho H. Jean , Jaffé Peter R. , MacLeod Cecilia L. , Koehnlein Susan A. 
Published: July 2010

AbstractA new method of collecting samples of unsaturated‐zone water for quantitative analysis for a volatile organic compound, trichloroethene (TCE), was compared to three other, previously described sampling methodologies in the laboratory and in the field. In the laboratory, prepared water samples containing TCE in a known concentration (20 µg/L) were sampled repeatedly by using each of the four methods to quantify method precision and accuracy. To compare the four methods in the field, unsaturated‐zone water above a TCE‐contaminated water‐table aquifer was transferred from a depth of 2 m to land surface with 0.15‐m‐long suction lysimeters attached to 1.85‐m lengths of stainless‐steel tubing. Statistical analyses of the laboratory and field data indicate that the new method, which involves collecting the water samples in gas‐tight glass syringes, is superior to the other three methods for the quantitative sampling and analysis of TCE on the basis of its high precision and accuracy and ease of use. This method was used to collect additional samples from the field site to quantify the spatial variability of TCE concentrations in the unsaturated‐zone water. Results of analysis of variance of the data indicate that the spatial concentration variability is important, and that differences in TCE concentration are statistically significant for horizontal distances less than 3.6 m.
Sludge‐Borne Salt Effects on Survival of Bradyrhizobium japonicum
Authors: Madariaga G. M. , Angle J. S. 
Published: July 2010

AbstractThe soil population of Bradyrhizobium japonicum, the microsymbiont of soybean [Glycine max (L.) Merr.], is reduced following land application of sewage sludge. Previous research on the ability of B. japonicum to survive in soil recently amended with sewage sludge has been conflicting as to whether sludge‐borne salts or heavy metals inhibit survival. To examine this question, sewage sludge compost was added to a rhizobia‐free, Sassafras sandy loam soil (Typic Hapludult, fine loamy mixed mesic) amended with various rates of sludge compost, inoculated with B. japonicum USDA 110 ARS and the mixture was incubated for 42 d. The population of B. japonicum was reduced to nearly undetectable levels when inoculated into soil amended with sludge compost at a rate of 25%. The sludge compost was subsequently leached with 3‐, 6‐, 9‐ and 12‐column void volumes of distilled water resulting in sludge compost samples with equal concentrations of heavy metals but decreasing concentrations of soluble salts. Leached and unleached compost samples were added to soil at a rate of 25% and the mixture inoculated with B. japonicum. Soil amended with sludge compost leached with six void volumes water exhibited the highest rhizobial population, while soil amended with unleached sludge compost contained the lowest rhizobial population. In soil amended with sludge compost leached with 3‐, 9‐, and 12‐void volumes water, populations were not significantly different. Results demonstrate that sludge‐borne soluble salts, and not heavy metals, are primarily responsible for short‐term reductions in bradyrhizobial populations following the application of very high rates of sludge to soil.
Aluminum in Soil Solutions from a Subalpine Spruce‐Fir Forest at Whiteface Mountain, New York
Authors: Miller E.K. , Huntington T.G. , Johnson A.H. , Friedland A.J. 
Published: July 2010

AbstractDirect or indirect Al toxicity has been suggested as a principal factor in forest tree declines. We monitored ambient soil solutions in undisturbed and experimentally manipulated soils from a fir [Abies balsamea (L.) Mill.]‐spruce forest on Whiteface Mountain, NY, in order to characterize soil solution Al concentrations over a range of acid anion loadings. Under both natural and experimental conditions total Al and labile Al concentrations rarely exceeded values (180–250 µmol L−1) associated with reduced root growth in red spruce (Picea rubens Sarg.). Over a 2‐yr period ambient soil solutions averaged 76 and 46 µmol L−1 total Al in the organic and mineral horizons, respectively. The highest monthly mean concentrations occurred in winter. Disturbance‐induced NO3 accumulation and simulated acid rain applications produced higher peak Al values in experimental plots than were observed in undisturbed and untreated plots. Although soils of the fir‐spruce zone exhibited the potential to yield solutions with phytotoxic Al concentrations, it appears that such concentrations are both spatially and temporally limited and infrequently present a direct stress to root growth in red spruce.
Dissolved Organic Matter and Adsorption‐Desorption of Dimefuron, Atrazine, and Carbetamide by Soils
Authors: Barriuso E. , Baer U. , Calvet R. 
Published: July 2010

AbstractDissolved organic matter (DOM) from several sources influenced the adsorption and the desorption by soil of three herbicides: dimefuron {4‐[2‐chloro‐4‐(3,3‐dimethylureido) phenyl]‐2‐t‐butyl‐1,3,4‐oxadiazolin‐5‐one},atrazine (2‐chloro‐4‐ethylamino‐6‐isopropyl‐amino‐striazine), and carbetamide [D‐N‐ethyl‐2‐(phenyl‐carbamoyloxy)propioamide)]. The DOM was endogenous (water soluble and humic compounds directly extracted from soil) or exogenous (water soluble organic matter from compounds applied to soils through agricultural practices: sewage sludge, fermented straw, and farmyard slurry; and two model compounds—tannic acid and an anionic surface active agent). Experiments were conducted to quantify the importance of herbicide sorption in three separate systems: DOM‐soil, DOM‐herbicide in solution, and DOM‐adsorbed herbicide. Herbicide adsorption strongly increased in the presence of water soluble materials from fermented straw, which explained the lowest desorption obtained with this DOM. On the other hand, the water soluble extracts of liquid or solid sludge favored herbicide desorption. Generally, adsorption of the less soluble herbicides (dimefuron and atrazine) was favored when soil was pretreated with DOM, and their adsorption generally decreased when DOM was preincubated with herbicides before soil contact. Opposite effects were generally noted for the most soluble herbicide (carbetamide). A new empirical, two‐compartment model provided a good description of desorption isotherms. The first compartment (a linear desorption) was similar for most DOM types. The differences in desorption isotherms were mainly related to the different behavior of the second compartment (an exponential desorption), in which the molecules were more strongly adsorbed.
Dependence of Aldicarb Residue Degradation Rates on Groundwater Chemistry in the Wisconsin Central Sands
Authors: Kraft George J. , Helmke Philip A. 
Published: July 2010

AbstractAldicarb sulfoxide (ASO) (2‐methyl‐2‐(methylsulfinyl)propanal O‐[(methylamino)carbonyl]oxime) and aldicarb sulfone (ASO2) (2‐methyl‐2‐(methylsulfonyl)propanal O‐[(methylamino)carbonyl]oxime) degradation rates were measured in incubations simulating three depths (0.5, 5, and 10 m) of Wisconsin central sand plain (WCSP) aquifer. The incubations differed mainly in pH (5.8, 6.5, and 7.2, respectively, for the three depths) and pO2 (20 kPa [0.2 atm] for the 0.5‐ and 5‐m depths, 1.5 kPa [0.015 atm] for the 10‐m depth). Degradation rates corresponded to half‐lives ranging from years to less than a month. Aldicarb sulfone (ASO2) degraded faster than ASO at the same depth. No ASO degradation was measured under aerobic, pH 5.8 conditions; no ASO oxidation was observed in any incubation. The shortest half‐lives, 19 and 32 d for ASO and ASO2, respectively, were obtained under the low pO2 conditions. The results of this and a previous experiment provide degradation rates for a cross‐section of WCSP groundwater chemistries. Thus, with knowledge of the groundwater chemistry at a given WCSP location, degradation rates can be estimated. Degradation rates of common groundwater contaminants as functions of chemical and physical controlling factors could prove valuable to groundwater managers for endeavors such as wellhead protection.