bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biosolids Effects on Phosphorus Retention and Release in Some Sandy Florida Soils
Authors: Lu Peng , O'Connor George A. 
Published: June 2010

ABSTRACTThe soil solid phase components most responsible for P sorption in Florida soils are Fe and Al oxides. Thus, we hypothesized that land application of biosolids would significantly increase a soil's P retention by increasing its content of P‐sorbing solids, especially when biosolids with high Fe and Al concentrations are applied to soils that sorb P poorly. Biosolids effects were quantified by a series of single‐point isotherms on soils from two field studies sampled for up to 4 yr after initial biosolids application. Biosolids additions had little effect on P retention in a soil with abundant oxalate‐extractable Fe and Al and a correspondingly large native P‐sorbing capacity. However, biosolids significantly increased P retention in a soil with low oxalate‐extractable Fe and Al content and low native P‐sorbing capacity. Biosolids effects on P retention lasted 1 to 3 yr after application, depending on biosolids source and rate of application, and generally mimicked persistence of increased extractable Fe and Al concentrations in the poorly P‐sorbing soil. Disappearance of added Fe and Al (and, hence, P retention capacity) from the surface horizons over time was relatively rapid, perhaps due to abundant organic acid production associated with biosolids degradation. Phosphorus in biosolids containing (or tailored to contain) abundant Fe and/or Al can be expected to behave as aslowly availableP source, and to be less subject to leaching losses than completely soluble P sources.
Tree Species for Recovering Nitrogen from Dairy‐Farm Effluent in New Zealand
Authors: Roygard Jon K.F. , Clothier Brent E. , Green Steve R. , Bolan Nanthi S. 
Published: June 2010

ABSTRACTLand treatment of dairy‐farm effluent is being widely adopted as an alternative to disposal into surface waters in New Zealand. This study investigated water balances and associated N leaching from short‐rotation forest (SRF) species irrigated with dairy‐farm effluent. Single trees were grown in lysimeters filled with Manawatu fine sandy loam (mixed mesic Dystric Eutrochrept). Dairy‐farm effluent was applied during two irrigation periods at 21.5 mm wk−1with a total loading equivalent to 870 kg N ha−1occurring over 17 mo. Following tree harvest in April 1997, measurements continued until August 1997 to monitor tree reestablishment. Cumulative N leached did not differ between lysimeters in which evergreen Sydney blue gum (Eucalyptus salignaSm.) and shining gum [Eucalyptus nitens(H. Deane & Maiden) Maiden] and deciduous kinu‐yanagi (Salix kinuyanagiKimura) were grown. Leachate N concentrations of all treatments were on average higher than the New Zealand drinking water standard of 11.3 mg N L−1TheE. nitensandS. kinuyanagitreatments leached 33 and 35 kg N ha−1yr−1in 1996 following application of 236 kg N ha−1during the first irrigation season. Leaf area was strongly correlated to evapotranspiration, drainage volume, and nitrogen leached. The majority of leaching in the tree treatments occurred after harvest. Reducing the leaching in the regrowth phase may be achieved through timing harvest in the spring when growth rates are higher and leaching potential is lower. Based on N uptake rates observed in this study and average pond discharge, a plantation of 5.4 ha would be required for N recovery on a typical dairy farm in New Zealand.
Effect of Flue Gas Desulfurization Residue on Plant Establishment and Soil and Leachate Quality
Authors: Punshon Tracy , Adriano Domy C. , Weber John T. 
Published: June 2010

ABSTRACTEffects on soil quality and crop establishment after incorporation of flue gas desulfurization by‐product (FGD) into soil as an amendment was assessed in a mesocosm study. Mesocosm units received applications equivalent to 0, 2.5, 5.0, 7.5, and 10% FGD residue [0, 25, 50, 75, and 100 tons acre−1]. Germination, biomass production, and elemental composition of corn (Zea mays L. var. Dekalb DK‐683), soybean [Glycine max (L.) Merr. var. Haskell Pupa 94], radish (Raphanus sativus L. var. Sparkler), and cotton (Gossypius hirsutus L. var. Deltapine 51) were determined. The quality of leachates and soil were also determined periodically. Flue gas desulfurization residue did not affect germination and all application rates stimulated aboveground biomass. Plants grown in FGD‐amended soil contained significantly elevated tissue concentrations of As, B, Se, and Mo. The FGD residue elevated surface soil pH from 5.5 (Control) to 8.1 (at 10% FGD). Leachate pH was unaffected by FGD, but salinity rose sharply with increasing application rates of FGD. Leachates contained higher concentrations of B, with small increases in Se and As. Flue gas desulfurization residue application caused an increase in total B, As, Mo, Se, and extractable Ca in the soil, but decreased Mn and Zn. Using FGD residues could have beneficial effects on crop establishment without detrimental effects on soil or leachate quality, at an optimum rate of approximately 2.5%. This material could alleviate surface acidity, and B and Mo deficiencies in plants.
Atmospheric Movements of Lindane (γ‐Hexachlorocyclohexane) from Canola Fields Planted with Treated Seed
Authors: Waite D.T. , Gurprasad N.P. , Sproull J.F. , Quiring D.V. , Kotylak M.W. 
Published: June 2010

ABSTRACTLindane (γ‐hexachlorocyclohexane [γ‐HCH]) is used as an insecticide in many countries. Concentrations of γ‐HCH have been found in air, water, soil, snow, and tissue samples throughout the world and concerns have been raised for its potential effects on human and ecosystem health. In Canada, γ‐HCH is primarily used as a treatment on canola (Brassica napus L) seed with an estimated 455.3 Mg applied in 1997 and 510.4 Mg in 1998. The purpose of this study was to measure γ‐HCH volatilization from fields planted with treated canola seed. Atmospheric dry and wet deposition and soil samples were collected for two growing seasons (1997 and 1998) from a canola field planted with treated seed. Atmospheric concentrations as high as 16.1 and 7.4 ng m−3 were measured at 1 m above the canola field compared with maximum concentrations of 2.9 and 2.7 ng m−3 measured above a grass field located 2 km away (1997 and 1998, respectively). On the basis of measurements made in this study it was estimated that between 12 and 30% of the γ‐HCH applied as canola seed treatment may volatilize and be released to the atmosphere. This would create an atmospheric loading of 66.4 to 188.8 Mg for the 6‐wk period following planting, estimated from the quantity of seed sown on the Canadian prairies in 1998. Dry deposition rates and rain concentrations as high as 2203 ng m−2 d−1 and 170 ng L−1 were measured adjacent to the canola field.
Major Herbicides in Ground Water: Results from the National Water‐Quality Assessment
Authors: Barbash Jack E. , Thelin Gail P. , Kolpin Dana W. , Gilliom Robert J. 
Published: June 2010

ABSTRACTTo improve understanding of the factors affecting pesticide occurrence in ground water, patterns of detection were examined for selected herbicides, based primarily on results from the National Water‐Quality Assessment (NAWQA) program. The NAWQA data were derived from 2227 sites (wells and springs) sampled in 20 major hydrologic basins across the USA from 1993 to 1995. Results are presented for six high‐use herbicides—atrazine (2‐chloro‐4‐ethylamino‐6‐isopropylamino‐s‐triazine), cyanazine (2‐[4‐chloro‐6‐ethylamino‐1,3,5‐triazin‐2‐yl]amino]‐2‐methylpropionitrile), simazine (2‐chloro‐4,6‐bis[ethylamino]‐s‐triazine), alachlor (2‐chloro‐N‐[2,6‐diethylphenyl]‐N‐[methoxymethyl]acetamide), acetochlor (2‐chloro‐N‐[ethoxymethyl]‐ N‐[2‐ethyl‐6‐methylphenyl]acetamide), and metolachlor (2‐chloro‐N‐[2‐ethyl‐6‐methylphenyl]‐N‐[2‐methoxy‐1‐methylethyl]acetamide)— as well as for prometon (2,4‐bis[isopropylamino]‐6‐methoxy‐s‐triazine), a nonagricultural herbicide detected frequently during the study. Concentrations were <1 μg L−1 at 98% of the sites with detections, but exceeded drinking‐water criteria (for atrazine) at two sites. In urban areas, frequencies of detection (at or above 0.01 μg L−1) of atrazine, cyanazine, simazine, alachlor, and metolachlor in shallow ground water were positively correlated with their nonagricultural use nationwide (P < 0.05). Among different agricultural areas, frequencies of detection were positively correlated with nearby agricultural use for atrazine, cyanazine, alachlor, and metolachlor, but not simazine. Multivariate analysis demonstrated that for these five herbicides, frequencies of detection beneath agricultural areas were positively correlated with their agricultural use and persistence in aerobic soil. Acetochlor, an agricultural herbicide first registered in 1994 for use in the USA, was detected in shallow ground water by 1995, consistent with previous field‐scale studies indicating that some pesticides may be detected in ground water within 1 yr following application. The NAWQA results agreed closely with those from other multistate studies with similar designs.
Using Rank‐Order Geostatistics for Spatial Interpolation of Highly Skewed Data in a Heavy‐Metal Contaminated Site
Authors: Juang Kai‐Wei , Lee Dar‐Yuan , Ellsworth Timothy R. 
Published: June 2010

ABSTRACTThe spatial distribution of a pollutant in contaminated soils is usually highly skewed. As a result, the sample variogram often differs considerably from its regional counterpart and the geostatistical interpolation is hindered. In this study, rank‐order geostatistics with standardized rank transformation was used for the spatial interpolation of pollutants with a highly skewed distribution in contaminated soils when commonly used nonlinear methods, such as logarithmic and normal‐scored transformations, are not suitable. A real data set of soil Cd concentrations with great variation and high skewness in a contaminated site of Taiwan was used for illustration. The spatial dependence of ranks transformed from Cd concentrations was identified and kriging estimation was readily performed in the standardized‐rank space. The estimated standardized rank was back‐transformed into the concentration space using the middle point model within a standardized‐rank interval of the empirical distribution function (EDF). The spatial distribution of Cd concentrations was then obtained. The probability of Cd concentration being higher than a given cutoff value also can be estimated by using the estimated distribution of standardized ranks. The contour maps of Cd concentrations and the probabilities of Cd concentrations being higher than the cutoff value can be simultaneously used for delineation of hazardous areas of contaminated soils.
Accumulation, Distribution, and Toxicity of Copper in Sediments of Catfish Ponds Receiving Periodic Copper Sulfate Applications
Authors: Han F.X. , Hargreaves John A. , Kingery William L. , Huggett Duane B. , Schlenk Daniel K. 
Published: June 2010

ABSTRACTCopper sulfate (CuSO4) is applied periodically to commercial channel catfish (Ictalurus punctatus) ponds as an algicide or parasiticide. Current understanding of the chemistry of copper in soil–water systems suggests that copper may accumulate in pond sediments, although the forms and potential bioavailability of copper in catfish pond sediments are not known. This study investigated the accumulation and distribution of copper in the sediment of catfish ponds receiving periodic additions of CuSO4 · 5H2O. All ponds were constructed in Sharkey (very‐fine, smectitic, thermic Chromic Epiaquert) soil. Nine 0.40‐ha ponds received 59 applications of 2.27 kg CuSO4 · 5H2O per application per pond over 3 yr; no CuSO4 · 5H2O applications were made to nine additional ponds. Total Cu concentration in the sediments of CuSO4 · 5H2O‐amended catfish ponds (172.5 mg kg−1) was four to five times higher than that in the sediments of nonamended ponds (36.1 mg kg−1). Copper accumulated in catfish pond sediments at a rate of 41 μg kg−1 dry sediment for each 1 kg ha−1 of CuSO4 · 5H2O applied to ponds. Copper in the sediments of amended ponds was mainly in the organic matter–bound (30.7%), carbonate‐bound (31.8%), and amorphous iron oxide–bound (22.1%) fractions with a considerable fraction (3.4%; 3 to 8 mg kg−1) in soluble and exchangeable fractions. This indicates that Cu accumulates differentially in various fractions, with proportionally greater initial accumulation in potentially bioavailable forms. However, toxicity bioassays with amphipods (Hyallela azteca) and common cattail (Typha latifolia L.) indicated that the effect of exposure to amended or nonamended pond sediments was not different.
Elevated Lead and Zinc Contents in Remote Alpine Soils of the Swiss National Park
Authors: Nowack Bernd , Obrecht Jean‐Marc , Schluep Mathias , Schulin Rainer , Hansmann Werner , Köppel Victor 
Published: June 2010

ABSTRACTWeathering of bedrock and pedogenic processes can result in elevated heavy metal concentrations in the soil. Small‐scale variations in bedrock composition can therefore cause local variations in the metal content of the soil. Such a case was found in the remote alpine area of the Swiss National Park. Soil profiles were sampled at an altitude of about 2400 m, representing soils developed above different bedrocks. The concentration of lead in the profiles was found to be strongly dependent on the metal content in the bedrock underlying the soil and was strongly enriched in the top 10 cm. The dolomitic bedrock in the study area contains elevated lead concentrations compared with other dolomites. Dissolution of dolomite and accumulation of weathering residues during soil formation resulted in high lead concentrations throughout the soil profile. The enrichment of lead in the topsoil, however, is largely attributed to atmospheric input. The isotopic signature of the lead clearly indicates that it is mainly of natural origin and that atmospheric deposition of anthropogenic lead contributed to about 20 to 40% to the lead concentration in the topsoil on the bedrock with elevated lead concentrations. In the soils on bedrock with normal lead concentrations, the anthropogenic contribution is estimated to be about 75%. Also, zinc was very strongly enriched in the topsoil. This enrichment was closely correlated with the organic matter distribution in the profiles, suggesting that recycling through plant uptake and litter deposition was a dominant process in the long‐term retention of this metal in the soil.
Assessment of the Risk of Phosphorus Loading Due to Resuspended Sediment
Authors: Koski‐Vähälä J. , Hartikainen H. 
Published: June 2010

ABSTRACTResuspension is a multiphase phenomenon where suspended solids encounter water layers differing in physico–chemical properties that affect the reactions of phosphorus (P). The role of resuspended sediment as a sink or source of dissolved P was determined in a laboratory study of P desorption–sorption equilibria. Gradual mixing was simulated using decreasing solid concentrations and varying environmental conditions (pH, redox, ionic strength). To describe the P exchange when the particles encounter dissimilar water layers, the extent of P sorption to or desorption from solids was expressed as a function of P concentration in the bath solutions. The equilibrium phosphorus concentration (EPC), at which there is no net P release from or retention to the particles, proved to be a suitable parameter for assessment of P load risk. Under oxic conditions at pH 7, commonly prevailing in lakes, the EPC values ranged from 11 to 27 μg P L−1 The larger the water volume the suspended material was mixed with, the higher the P concentration, allowing desorption to occur. As for chemical factors affecting P mobilization, EPC followed the order: pH 7 < pH 7 anoxic < pH 9. A separate extraction experiment revealed that elevated pH enhanced P mobilization more as the concentration of solids decresed. The results demonstrate that high pH (a common characteristic in eutrophic lakes during summer), when linked with intensive resuspension, may markedly increase the internal P loading risk. As for the risk assessment, the quantification of the internal P loading would be improved by isotherm studies combined with field observations.
Precipitation and River Water Chemistry of the Piracicaba River Basin, Southeast Brazil
Authors: Williams Michael R. , Filoso Solange , Martinelli Luiz A. , Lara Luciene B. , Camargo Plínio B. 
Published: June 2010

ABSTRACTAnnual precipitation and river water volumes and chemistry were measured from 1995 to 1998 in a mesoscale agricultural area of southeast Brazil. Precipitation was mildly acidic and solute concentrations were higher in the west than in the east of the basin. Combustion products from biomass burning, automobile exhaust, and industry typically accumulate in the atmosphere from March until October and are responsible for seasonal differences observed in precipitation chemistry. In river waters, the volume‐weighted mean (VWM) concentrations of major solutes at 10 sites across the basin were generally lower at upriver than at downriver sampling sites for most solutes. Mass balances for major solutes indicate that, as a regional entity, the Piracicaba River basin was a net sink of H+, PO3−4, and NH+4, and a net source of other solutes. The main stem of the Piracicaba River had a general increase in solute concentrations from upriver to downriver sampling sites. In contrast, NO−3 and NH+4 concentrations increased in the mid‐reach sampling sites and decreased due to immobilization or utilization in the mid‐reach reservoir, and there was denitrification immediately downriver of this reservoir. Compared with tributaries of the Chesapeake Bay estuary, the Piracicaba River is affected more by point‐source inputs of raw sewage and industrial wastes than nonpoint agricultural runoff high in N and P. Inputs of N and C are responsible for a degradation of water quality at downriver sampling sites of the Piracicaba River drainage, and water quality could be considerably improved by augmenting sewage treatment.
Herbicide Transport to Surface Waters at Field and Watershed Scales in a Mediterranean Vineyard Area
Authors: Louchart Xavier , Voltz Marc , Andrieux Patrick , Moussa Roger 
Published: June 2010

ABSTRACTThe contamination of soil and runoff water by two herbicides, diuron [N′‐(3,4‐dichlorphenyl)‐N,N‐dimethylurea] and simazine (6‐chloro‐N,N′‐diethyl‐1,3,5‐triazine‐2,4‐diamine), were monitored on two fields, one no‐till and one tilled. Experiments were carried out in a 91.4‐ha watershed in southern France during the 1997 growing season in order to understand the patterns of pesticide transport from field to watershed. The persistence of the herbicides in soil was prolonged due to the climatic conditions. At the field scale, annual herbicide loads were due to overland flow and amounted to 65.6 and 6.3 g ha−1 of diuron for the no‐till and tilled field, respectively, and to 29.6 and 1.83 g ha−1 of simazine. Maximum herbicide concentrations exceeded 580 μg L−1 during the first storm event after application and decreased thereafter but remained for 8 mo above 0.1 μg L−1 At the watershed outlet, estimated annual loads amounted to 4.12 g ha−1 of diuron and 0.56 g ha−1 of simazine. Among them, 96% of the losses in diuron and 83% of those in simazine were caused by the fast transmission through the network of ditches of the overland flow exiting the fields. For diuron, which was sprayed over most of the vineyards, its in‐stream concentrations during storm flow were close to those at the outlet of the fields. The herbicide loads in baseflow were smaller than 0.2 g ha−1 The patterns of the loads at the field and watershed scales suggested that a major part of the herbicides leaving the fields reinfiltrated to the ground water by seepage through the ditches, and was there degraded or adsorbed.
Factors Affecting the Ratio of Cation Exchange Capacity to Clay Content in Lignite Overburden
Authors: Stewart W.M. , Hossner L.R. 
Published: June 2010

ABSTRACTUnusually high cation exchange capacity (CEC) values relative to clay content are frequently reported for lignite overburden and minesoils. The CEC to percent clay ratio is commonly greater than one and would require that the average charge of the clay fraction be greater than 100 cmolckg−1A comparison of methods for particle‐size distribution suggests that the major reason lignite overburden samples have CEC to percent clay ratios greater than one is incomplete dispersion of aggregates of clay minerals or shale fragments. Preliminary investigations revealed the presence of shale fragments, smectite, and partially weathered mica in the silt fraction. Methods commonly used in soil textural analysis underestimated clay content by approximately 24%. The silt fraction may, therefore, provide a “hidden” source of CEC. Another important factor influencing the CEC to percent clay ratio was the presence of organic materials (lignite) in the samples. Lignite may make a significant contribution to CEC in overburden materials. In a study designed to estimate the pH‐dependent charge of both the mineral and organic fractions, the CEC of overburden organic constituents was determined to be approximately 158 cmolckg−1at pH 8.2. The high CEC to percent clay ratio in lignite overburden and minesoils may be resolved by adjusting methods for clay determination to optimize dispersion and by accounting for CEC due to organic materials. An alternative approach is to use existing methodology and use correction factors to account for incomplete dispersion of clay minerals and the charge contributions of organic materials.
Tracing Nitrate Transport and Environmental Impact from Intensive Swine Farming using Delta Nitrogen‐15
Authors: Karr Jonathan D. , Showers William J. , Gilliam J.Wendell , Andres A.Scott 
Published: June 2010

ABSTRACTNatural‐abundance δ15N showed that nitrate generated from commercial land application of swine (Sus scrofa domesticus) waste within a North Carolina Coastal Plain catchment was being discharged to surface waters by ground water passing beneath the sprayfields and adjacent riparian buffers. This was significant because intensive swine farms in North Carolina are considered non‐discharge operations, and riparian buffers with minimum widths of 7.6 m (25 ft) are the primary regulatory control on ground water export of nitrate from these operations. This study shows that such buffers are not always adequate to prevent discharge of concentrated nitrate in ground water from commercial swine farms in the Mid‐Atlantic Coastal Plain, and that additional measures are required to ensure non‐discharge conditions. The median δ15N‐total N of liquids in site swine waste lagoons was +15.4 ± 0.2‰ vs. atmospheric nitrogen. The median δ15N‐NO3 values of shallow ground water beneath and adjacent to site sprayfields, a stream draining sprayfields, and waters up to 1.5 km downstream were +15.3 ± 0.2 to +15.4 ± 0.2‰. Seasonal and spatial isotopic variations in lagoons and well waters were greatly homogenized during ground water transport and discharge to streams. Neither denitrification nor losses of ammonia during spraying significantly altered the bulk ground water δ15N signal being delivered to streams. The lagoons were sources of chloride and potassium enrichment, and shallow ground water showed strong correlation between nitrate N, potassium, and chloride. The 15N‐enriched nitrate in ground water beneath swine waste sprayfields can thus be successfully traced during transport and discharge into nearby surface waters.