Journal of Environmental Quality 30:677-682 (2001)
© 2001 American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America
EXECUTIVE SUMMARIES
This Issue in Journal of Environmental Quality
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Reducing Agricultural Pesticide Risk
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The Province of Ontario, Canada, has a goal reducing pesticide use to 50% of the amount of active ingredient used in 1983. However, concerns have been voiced that the reduction in use is occurring because low-use, high-risk compounds are replacing high-use, low-risk compounds. Gallivan et al. show that pesticide use declined 40% from 1983 to 1998, primarily because of reduced pesticide use on corn and tobacco. Pesticide risk also declined by 40%, with the greatest decline in the risk to farm workers. Even though many high-risk pesticides were no longer used, the risk per kg of pesticide did not change. Pesticide risk was calculated using the Environmental Impact Quotient, a scoring system for potential pesticide risk to farm workers, consumers, and the environment. The changing patterns in pesticide use and risk over time allow us to better understand the factors influencing pesticide use and highlight areas for future action.
G.A. Surgeoner (oaft@sentex.net)
Pesticide Risk Reduction on Crops in the Province of Ontario. J. Environ. Qual.30:798–813.
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Monitoring Nitrate Leaching from Submerged Drains
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Monitoring nitrate nitrogen (NO3–N) leaching is important to judge the effect that agricultural practices have on the quality of ground water and surface water. De Vos describes a new flow-proportional drainage water sampling method for submerged drains to monitor NO3–N leaching. Low and high discharge rates can be measured accurately, and are automatically compensated for fluctuations in ditch-water levels. Errors of up to 43% may occur when NO3–N concentrations in the drainage water are only measured at intervals of 30 days and when the precipitation excess is used to estimate cumulative NO3–N leaching. Measurements of NO3–N concentrations in ground water cannot be used to accurately estimate NO3–N leaching in drained soils.
J.A. de Vos
(j.a.devos@alterra.wag-ur.nl)
Monitoring Nitrate Leaching from Submerged Drains. J. Environ. Qual. 30:1092–1096
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Plant Uptake of Cadmium-109 and Zinc-65 from Soil
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The uptake of trace elements by plants is not only controlled by the plant itself but also by soil and environmental conditions. Almås and Singh now report that the addition of organic matter and the increasing temperature separately result in higher uptake of metals by ryegrass. They monitored uptake of 109Cd and 65Zn and their stable isotopes from soil by ryegrass at two temperatures and additions of organic matter. The organic matter may have increased the metal carrying capacity for soil solution by formation of dissolved metal organic complexes. However, the effect of temperature was more important because increasing temperature improved the conditions for plant growth. Since there was good consistency between the observed plat uptake and the presumably plant-available physico–chemical forms of cadmium and zinc in soil and soil solution, solid phase fractionation and speciation of metals in soil solution can provide valuable information about their bioavailability.
Å. R. Almås (asgeir.almas@ijvf.nlh.no)
Plant Uptake of Cadmium-109 and Zinc-65 at Different Temperature and Organic Matter Levels. J. Environ. Qual. 30:869–877
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Minimizing Endosulfan Transport
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Endosulfan, a pesticide that is widely used in Australia's cotton industry, is a risk to the downstream riverine environment, where it is highly toxic to aquatic organisms. Connolly and coworkers used the GLEAMS model used to evaluate management scenarios aimed at minimizing endosulfan transport from cotton fields in Queensland and New South Wales. They conclude that endosulfan transport from cotton farms can be minimized with a combination of field management that reduces excess irrigation and concentration of pesticide on the soil. However, discharges will still occur in storm events, with endosulfan concentrations exceeding guideline values.
R. Connolly (connolr@dnr.qld.gov.au)
Simulating Endosulfan Transport in Runoff from Cotton Fields in Australia with the GLEAMS Model. J. Environ. Qual. 30:702–713
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Spray, Vapor, and Runoff Transport Endosulfan from Farms to Rivers
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Endosulfan has been detected in significant concentrations in rivers in the irrigated cotton-growing areas of northern New South Wales, Australia. This has been attributed to a variety of airborne and waterborne transport pathways. Raupach et al. describe an integrated modeling approach to assess the absolute and relative contributions to riverine endosulfan concentrations of three airborne pathways (spray drift, vapor transport, and dust transport) and a waterborne pathway (surface runoff). They used an averaging process to calculate regional-scale effects. Results show that spray drift, vapor transport, and runoff are all significant pathways, but dust transport is insignificant. Spray drift and vapor transport both contribute low-level but nearly continuous inputs to the riverine endosulfan load during spraying season, whereas runoff provides occasional but higher inputs. A companion paper shows that the model findings are in broad agreement with typical riverine endosulfan concentrations in two rivers, and are further supported by process tests with field and laboratory data.
M.R. Raupach
(Michael.Raupach@cbr.clw.csiro.au)
Endosulfan Transport: I. Integrative Assessment of Airborne and Waterborne Pathways. J Environ. Qual. 30:714–728
Endosulfan Transport: II. Modeling Airborne Dispersal and Deposition by Spray and Vapor. J. Environ. Qual. 30:729–740
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Endosulfan Toxicity in Water and Sediment
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In the cotton-growing regions of Australia, concentrations of the pesticide endosulfan in river water have been correlated with decreases in population densities of mayfly nymphs and caddisfly larvae. Sorption onto and from sediment particle surfaces could influence the bioavailability of endosulfan entering rivers during storm runoff events. Leonard et al. now describe the chemical fate and toxicity of endosulfan isomers and their sulfate metabolite toward the burrowing mayfly nymph (Jappa kutera). The results suggest that endosulfan sulfate in water is more acutely toxic to riverine biota than either the parent endosulfan isomers or endosulfan compounds in contaminated sediment. Aqueous concentrations of endosulfan sulfate were relatively high and persistent.
R.V. Hyne (Hyner@epa.nsw.gov.au)
Fate and Toxicity of Endosulfan in Namoi River Water and Bottom Sediment. J. Environ. Qual. 30:750–759
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Mineral Surfaces Adsorb Pesticides
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Pesticide adsorption has primarily been investigated in soils where the organic carbon content is the main factor controlling sorption. However, adsorption of pesticides to aquifer sediments with low organic carbon content is controlled also by mineralogy, pH, cation exchange capacity, ionic strength, and surface area. Clausen et al. have determined the adsorption of pesticides to pure minerals to quantify the contributions to sorption of different constituents of aquifer solids. Detectable adsorption of anionic pesticides was only measured at pH values where positive sites were present on the mineral. Adsorption of nonionic pesticides was only measured on the investigated clay mineral. The results illustrate that the magnitude of adsorption depends on the type of pesticide, the type of mineral, and pH.
L. Clausen (igglc@pop.dtu.dk)
Adsorption of Pesticides onto Quartz, Calcite, Kaolinite, and 
-Alumina. J. Environ. Qual. 30:846–857
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Pros and Cons of Recycling FGD Residue as a Soil Amendment
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Abundant residues from coal combustion can have beneficial effects on crop growth. Flue gas desulfurization (FGD) residue, resulting from the removal of sulfur dioxide from waste gases, contains calcium sulfite and gypsum, and can be used to enhance water holding capacity and ameliorate surface acidity. Punshon et al. report a threefold increase in biomass of corn, soybean, cotton, and radish where FGD reside was applied at rates from 0 to 224 Mg/ha (0–100 tons/acre) on weathered Southeastern Atlantic Coastal Plain soils. Surface soil pH increased from 5 to 8, and leachate salinity rose from 0.05 to 3.5 dS m-1. Negative effects included an increase in heavy metal content (especially boron, arsenic, and selenium) of soil, plants, and leachate. These concentrations remained below maximum critical limits, but can be used to establish guidelines for safe application of this residue in the field. Results suggest moderate application rates will stimulate biomass and avoid excessive metal enrichment.
T. Punshon (punshon@srel.edu)
Effect of Flue Gas Desulfurization Residue on Plant Establishment and Soil and Leachate Quality. J. Environ. Qual. 30:1071–1080
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Sludge Dissolved Organic Matter Increases Copper Leaching Loss
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Addition of organic wastes to soil will increase dissolved organic matter content (DOM), which may affect the sorption of copper (Cu) in soils. Zhou and Wong report results of a batch equilibrium study showing that DOM of both sludge and sludge compost reduced Cu sorption markedly for a calcareous soil and to a lesser extent for acidic soil. The decrease in Cu sorption was consistently higher for DOM derived from sludge than sludge compost because of the higher hydrophobic fraction in the latter. At a pH > 6.8, the sorption of Cu decreased with the presence of DOM. Results suggest that application of C enriched organic wastes to calcareous soils contaminated with Cu might facilitate the leaching loss of Cu to surface and ground water.
J. Wong (jwcwong@hkbu.edu.hk)
Effect of Dissolved Organic Matter from Sludge and Sludge Compost on Soil Copper Sorption. J. Environ. Qual. 30:878–883
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Major Herbicides in Ground Water of the United States
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Results from sampling 2227 wells and springs in 20 major hydrologic basins across the United States from 1993 to 1995 during the National Water-Quality Assessment (NAWQA) Program provide clues regarding the factors that control the likelihood of detecting pesticides in ground water. Barash and coworkers report that in urban areas, detections at or above 0.01 µg/L in shallow ground water were significantly more frequent for herbicides with higher nonagricultural use nationwide. Frequencies of detection in agricultural areas were significantly higher for herbicides with greater agricultural use near the sampled sites, and greater persistence in aerobic soil. Acetochlor, an agricultural herbicide first registered for use in 1994, was detected in shallow ground water by 1995. Comparisons with results from other large-scale investigations demonstrated some of the ways in which study design may affect the frequencies of pesticide detection in ground water.
J. Barbash (jbarbash@usgs.gov)
Major Herbicides in Ground Water: Results from the National Water-Quality Assessment. J. Environ. Qual. 30:831–845
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Particulate Selenium Fluxes Dominate in Intertidal Wetlands
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Releases of refinery effluent to the San Francisco Bay have caused selenium accumulation in the estuary, including adjacent intertidal wetlands. Zawislanski et al. report that, despite elevated dissolved selenium concentrations in San Francisco Bay water, suspended particulate matter is the primary source of selenium to the wetlands. Detailed mapping of sediment selenium in two intertidal wetlands and direct measurements of deposition using sediment traps revealed an additional 20 to 25% selenium enrichment in the thickly vegetated marsh plain, probably due to in situ adsorption from overlying water and chemical reduction. In the barren tidal flat, sediment profiles indicate a minor net selenium loss at the sediment–water interface, likely due to exchange between porewater and tidal waters. These findings highlight the need for more intensive monitoring of selenium in suspended particulate matter in San Francisco Bay water and additional studies of selenium exchange in tidal flats.
P. Zawislanski
(PTZawislanski@lbl.gov)
Selenium Distribution and Fluxes in Intertidal Wetlands, San Francisco Bay, California. J. Environ. Qual. 30:1080–1091
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Pesticides Adsorbed onto Iron Oxides
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In aquifer sediments, where the organic carbon content is low, pesticides may become associated with mineral surfaces. Of the various inorganic aquifer components, clay minerals and iron oxides have the greatest potential for pesticide adsorption due to the large surface area and the functional groups of these constituents. Clausen and Fabricius report that adsorption of several nonionic pesticides on common iron oxides in aquifer sediments was insignificant, whereas adsorption of acidic pesticides was significant on all iron oxides investigated. Adsorption of the acidic pesticides was strongly dependent on pH, the electrolyte used, and the site density on the iron oxides.
L. Clausen (igglc@pop.dtu.dk)
Atrazine, Isoproturon, Mecoprop, 2,4-D, and Bentazone Adsorption onto Iron Oxides. J. Environ. Qual. 30:858–869
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Atmospheric Lindane: The Canola Connection
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Waite et al. report that as much as 30% of the lindane applied to Canadian prairie canola fields enters the atmosphere by volatilization. Volatilization of lindane from canola fields may contribute significantly to global atmospheric concentrations of this chemical. Lindane, an insecticide, is extensively used in many countries and residues have been found all over the world, including the Arctic and the Antarctic. Lindane application in Canada is primarily for the treatment of agricultural seeds before planting. Approximately 95% of the canola seed planted on 5.5 million hectares of Canadian prairie fields is treated with lindane, an estimated application of 510.4 tonnes. The authors conclude that seed treatments should be considered potential sources of atmospheric contaminants.
D. Waite (Don.Waite@ec.gc.ca)
Atmospheric Movements of Lindane (
-Hexachlorocyclohexane) from Canola Fields Planted with Treated Seed. J. Environ. Qual. 30:768–775
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Herbicide Transport from Field to Watershed
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Pesticides that are widely used in vineyards in the Mediterranean region contaminate many surface and ground water bodies. Louchart et al. now show that herbicide loads decreased largely between field and watershed scales and that herbicide transport patterns from field to watershed were mainly influenced by the network of ditches. These results were obtained by monitoring the contamination of soil and runoff water by two herbicides on two fields and at the outlet of a vineyard watershed in southern France. Therefore, retarding field to stream transmission of the contaminated overland flow by encouraging infiltration in the ditches appears to be a possible way for minimizing herbicide movement to surface water.
X. Louchart
(xavier.louchart@ensam.inra.fr)
Herbicide Transport to Surface Waters at Field and Watershed Scales in a Mediterranean Vineyard Area. J. Environ. Qual. 30:982–991
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High Iron and Aluminum Biosolids Minimize Surface Water Eutrophication Risk
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Land applications of biosolids can be significant sources of phosphorus (P) to a watershed and sensitive water bodies therein. Concerns over eutrophication of surface waters in Florida threaten continued recycling of biosolids to land. However, Lu and O'Conner report that not all biosolids and soils have the same risk of P contamination because some biosolids improve P retention by augmenting the P-sorbing solids content of amended soils. Biosolids containing abundant iron (Fe) and aluminum (Al) improved P retention in a poorly P-adsorbing sand, but had little effect on P sorption in a sand that already contained abundant P-sorbing solids. Increased P retention lasted 2 to 3 years in the poorly P-adsorbing sand before disappearing, and the effect was well correlated with initial increases and subsequent decreases in extractable Fe and Al concentrations in the various treatments over time. Phosphorus in biosolids containing abundant Fe and/or Al can be expected to behave as slowly available P sources and to be less subject to leaching losses than fertilizer P sources.
G.A. O'Connor (gao@ufl.edu)
Biosolids Effects on Phosphorus Retention and Release in Some Sandy Florida Soils. J. Environ. Qual. 30:1059–1063
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Rank Order Geostatistics Delineates Contaminated Soils
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The spatial interpolation of pollutants is essential for delineating hazardous areas in contaminated soils. Juang et al. report that rank order geostatistics with standardized rank transformation is useful for the spatial interpolation of pollutants with a highly skewed distribution in contaminated soils. The method is valuable when commonly used nonlinear methods, such as logarithmic and normal scored transformation, are not suitable. Contour maps of pollutant concentrations and the probabilities of pollutant concentrations being higher than a cutoff value can be obtained using the rank order geostatistical approach. A data set of soil cadmium concentrations with great variation and high skewness in a contaminated site of Taiwan is used for illustration.
Dar-Yuan Lee
(dylee@ccms.ntu.edu.tw)
Using Rank-Order Geostatistics for Spatial Interpolation of Highly Skewed Data in a Heavy-Metal Contaminated Site. J. Environ. Qual. 30:894–903
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Management Affects Denitrification from Outdoor Pig Production
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Animal welfare considerations have stimulated the development of outdoor pig production systems. Such systems have a high potential for atmospheric losses of nitrogen in animal excreta, which are deposited at the soil surface under a wide range of climatic conditions. Petersen et al. report that denitrification accounted for 69 kg nitrogen per hectare per year, or 11% of the nitrogen surplus in the piglet production system. Along with denitrification, soil concentrations of inorganic nitrogen and dissolved organic carbon were elevated around feeding sites and huts. Nitrogen use efficiency of pig production could be increased by management changes to optimize feeding, and relocation of huts and feeders to obtain a more uniform distribution of nutrients.
S.O. Petersen
(soren.o.petersen@agrsci.dk)
Denitrification Losses from Outdoor Piglet Production: Spatial and Temporal Variability. J. Environ. Qual. 30:1051–1058
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Sulfides Predict Composting Odors
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Odor pollution is a major problem facing mushroom compost production, and techniques are needed for evaluating the effectiveness of odor control measures. Noble et al. show that the combined concentration of hydrogen sulfide and dimethyl sulfide of mushroom composting air samples is closely correlated with their odor concentration determined by an odor panel. This relationship will enable objective, rapid, and low-cost identification of odor sources on mushroom composting sites, since the concentrations of the two sulfides can be determined with gas detector tubes. The authors also show that aeration of composting heaps and windrows reduces the odor and sulfide concentrations of the air by 87 and 92%.
R. Noble (ralph.noble@hri.ac.uk)
Olfactory Response to Mushroom Composting Emissions as a Function of Chemical Concentration. J. Environ. Qual. 30:760–767
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Landfarm Emissions Monitor Developed
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Landfarming is the practice of mixing organic, heavy metal, or other inorganic materials into surface soil where they are converted to constituents that are not hazardous to human health or the environment. The release of trace gases such as hydrocarbons from landfarming facilities could impair regional air quality or pose health risks to on-site workers. Hydrocarbon volatilization during landfarming is frequently assumed negligible, but few studies have directly measured volatilization. Ausma et al. have developed a novel flux gradient micrometeorological technique to monitor total hydrocarbon emissions from active refinery and bioremediation landfarms. High-resolution gradient measurements and maximized sensitivity were accomplished through design features in the sampling system and through high-frequency instrument sampling. Results from three field studies at active facilities were used to illustrate the technique.
S. Ausma (sausma@uoguelph.ca)
A Micrometeorological Technique to Monitor Total Hydrocarbon Emissions from Landfarms to the Atmosphere. J. Environ. Qual. 30:776–785
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Biosolids-Amended Soils Adsorb Cadmium
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In development of the regulations for land application of biosolids, the USEPA relied on the reduction in plant-available Cd in soils amended with biosolids compared with soils amended with inorganic salts. This resulted in debates over the biosolids phase (organic or inorganic) responsible, and its long-term efficacy. Li et al. evaluated Cd adsorption by biosolids-amended soils and now report that adsorption is greater in the biosolids-amended soil than in control soils. The removal of organic carbon from the samples reduced Cd adsorption, but the difference between biosolids-amended and their control soil was still apparent, suggesting that the increased retention of Cd on biosolids-amended soils is independent of the added organic matter and thus, of a persistent nature.
J. Ryan (Ryan.Jim@epamail.epa.gov)
Adsorption of Cadmium on Biosolids-Amended Soils. J. Environ. Qual. 30:903–911
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Copper a Chemical Time-Bomb?
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Copper (Cu) is a contaminant in many soils due to intensified use of fungicides, and application of sewage sludge, waste from timber preservation industry, and acid mines. Copper accumulating in the soil surface will slowly move to the ground water, becoming a contaminant. But this can take decades. To better understand the mechanisms involved in copper transport, Vogeler studied Cu and calcium (Ca) movement and exchange through a repacked soil column of Manawatu fine sandy loam. Copper and Ca behavior was simulated using the convection–dispersion equation linked with cation exchange theory. The results indicate that exchange between Ca and Cu is the main process of Cu retardation in the Manawatu soil.
I. Vogeler (ivogeler@hort.cri.nz)
Copper and Calcium Transport through an Unsaturated Soil Column. J. Environ. Qual. 30:927–933
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To Reduce Sediment Losses Versus Soluble Nutrient Losses
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Poor water quality of the Minnesota River, the upper Mississippi River, and the Gulf of Mexico has been blamed in part on intensive cultivation in southern Minnesota where surface and subsurface drainage are common. Zhao et al. describe the effects of ridge tillage (RT) and moldboard plowing (MP) on sediment and nutrient losses in surface runoff and subsurface tile drainage from a clay loam soil. Ridge tillage, which did not incorporate surface residue and amendments, lost more soluble nutrients than MP. Although MP thoroughly mixed residue and amendments in surface soil, soil disturbance caused more sediment and sediment-associated nutrient losses than RT. If these trends are consistent on an annual basis, these opposing impacts could pose a dilemma when considering high residue tillage system alternatives for artificially drained soils.
S.C. Gupta (sgupta@soils.umn.edu)
Tillage and Nutrient Source Effects on Surface and Subsurface Water Quality at Corn Planting. J. Environ. Qual. 30:998–1008
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Acid Mine Drainage Evaluation
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Inconsistent performance has hampered widespread use of successive alkalinity producing systems (SAPS) for treating acidic mine drainage. Jage et al. used data from 13 operating SAPS cells to construct a statistical model describing SAPS performance. Results show that three factors accounted for 68% of the variability in net alkalinity generation by the operating SAPS. The response of alkalinity generation to limestone-layer residence time appears logarithmic, representing the decreasing rate of limestone dissolution as calcite saturation is approached. Two acidity-related influent water-chemistry parameters also appear to affect SAPS performance due to their effect on calcite solubility.
C.E. Zipper (czip@vt.edu)
Factors Affecting Alkalinity Generation by Successive Alkalinity-Producing Systems: Regression Analysis. J. Environ. Qual. 30:1015–1022
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Spray Drift Causes Contamination Downstream
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During spray application, wind may cause pesticides to be transported to adjacent nontarget areas. However, the importance of these processes for the contamination of surface water ecosystems has rarely been studied. Schulz et al. now show that orchard insecticides transported via spray drift to small streams contaminate subsequent river stretches a few kilometers downstream of the sprayed plots. The deposition of azinphos-methyl and endosulfan in containers of water and the contamination of drift-receiving side streams as well as the Lourens River in the Western Cape of South Africa were investigated under usual farming conditions. Results suggest a link between spray deposition, surface water toxicity, and decreased downstream water quality.
R. Schulz (R.Schulz@tu-bs.de)
Spray Deposition of Two Insecticides into Surface Waters in a South African Orchard Area. J. Environ. Qual. 30:814–822
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Biosolids Treatment Affects Soil Phosphorus Availability
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Biosolids (municipal sewage sludge) have long been applied to agricultural land on the basis of plant-available nitrogen, also taking into account trace metal content and loading rates. In the U.S. mid-Atlantic states, regulations mandating phosphorus (P)-based nutrient management plans are becoming more common, indicating that future biosolids application rates may be limited by P. Maguire et al. report that P availability and potential mobility in biosolids-amended soils depended on the wastewater treatment process (e.g., lime stabilization, metal salt addition) used to produce the biosolids. Results suggest that testing biosolids for Mehlich-3 P or the P/(Al+Fe) ratio, rather than total P, was most useful at predicting the effect of biosolids application on the availability and potential mobility of P in biosolids-amended soils.
R.O. Maguire (rmaguire@udel.edu)
Relationship between Biosolids Treatment Process and Soil Phosphorus Availability. J. Environ. Qual. 30:1023–1033
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Pollutants have Half Lives, Too
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Thortensen and Lode report that propiconazole and bentazone are potential pollutants to the environment due to their persistence with half-lives longer than 84 days, whereas dichlorprop and MCPA were degraded within 7 to 38 days. Results are based on laboratory degradation studies where a combination of bentazone, dichlorprop, MCPA, or propiconazole alone were applied to representative Norwegian soils.
C.W. Thorstensen
(christian.thorstensen@planteforsk.no)
Laboratory Degradation Studies of Bentazone, Dichlorprop, MCPA, and Propiconazole in Norwegian Soils. J. Environ. Qual. 30:947–953
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Aging Does Not Affect Cadmium Transport
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Transport of cadmium (Cd) in acid sandy soils is governed by a mixture of physical and chemical processes. Seuntjens et al. now show that the contact time of Cd between soil solution and solid soil phase does not affect the Cd transport processes. The results are based on displacement experiments with a stable 111Cd isotope in undisturbed Cd-contaminated soil cores. The simultaneous analysis of 111Cd isotope and indigenous Cd in the soil column's effluent could not indicate a difference in transport behavior between the two Cd species. This means Cd that is present for a period of several decades in soil will remain available for uptake by plants and soil organisms and for leaching to ground water.
Piet Seuntjens
(piet.seuntjens@vito.be)
Aging Effects on Cadmium Transport in Undisturbed Contaminated Sandy Soil Columns. J. Environ. Qual. 30:1040–1050
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Agriculture Alters Methane Consumption Capacity of Soil
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Methane is a potent greenhouse gas, and soil microorganisms play an active role in both the consumption and production of atmospheric methane. Land use may selectively impact consumption and production of methane. Chan and Parkin report that although forest and prairie systems are net consumers of atmospheric methane, in agricultural soils methane consumption is diminished. Agricultural systems receiving swine manure applications are net producers of methane. The authors suggest that in the manured systems high methane fluxes might be due to out-gassing of dissolved methane from the manure slurry. It appears that municipal landfills, despite the relatively small proportion of land they represent, may have a large effect on land-based methane emissions.
T. Parkin (parkin@nstl.gov)
Effect of Land Use on Methane Flux from Soil. J. Environ. Qual. 30:786–797
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Pesticide Runoff from Turfgrass Modeled
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Pesticides applied to turfgrass on golf courses, parks, and lawns can be washed by rain and irrigation to contaminate streams and lakes. It is difficult to measure the extent of such pollution, but mathematical models could be used to provide this information. Unfortunately, existing models were developed for agricultural crops and do not work well for turfgrass. Haith now describes a new model, TurfPQ, that was developed specifically for turfgrass. The model is simple to use and provides reliable pesticide runoff estimates for a wide variety of chemicals, sites, and weather conditions.
D.A. Haith (dah13@cornell.edu)
TurfPQ, A Pesticide Runoff Model for Turf. J. Environ. Qual. 30:1033–1039
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Furrow Irrigation Runoff Contains Phosphorus
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Phosphorus applications to agricultural land may be restricted if runoff losses are related to soil phosphorus availability. Losses from agricultural land can cause eutrophication by accelerating algae and aquatic plant growth in lakes, rivers, and streams. Westermann et al. report that soluble phosphorus concentrations increased in irrigation runoff as soil phosphorus availability increased. Total phosphorous concentration was related to runoff sediment and extractable soil organic phosphorus concentrations. Results were based on runoff data from established field plots with a wide range of soil phosphorous availability from manure, whey, and commercial fertilizer applications. The potential for soluble phosphorus losses increases as soil phosphorus availability increases. Organic phosphorus sources, such as manure, appear to contribute more to runoff losses than inorganic phosphorus fertilizer materials. Total phosphorus losses from surface-irrigated land will be significantly reduced if soil erosion is controlled.
D.T. Westermann
(dtw@kimberly.ars.pn.usbr.gov)
Phosphorus Losses in Furrow Irrigation Runoff. J. Environ. Qual. 30:1009–1015
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Forests for Effluent Treatment in New Zealand
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Land treatment of dairy farm effluent is being widely adopted as an alternative to direct disposal into surface waters in New Zealand. Roygard et al. report results from a lysimeter study showing that short rotation forests are a viable option for nitrogen recovery on a typical dairy farm. Cumulative nitrogen leached did not differ among treatments of evergreen Eucalyptus saligna, E. nitens, and the deciduous Salix kinuyanagi. Most nitrogen leaching occurred after harvests as trees reestablished.
J. Roygard (jroygard@vt.edu)
Tree Species for Recovering Nitrogen from Dairy-Farm Effluent in New Zealand. J. Environ. Qual. 30:1064–1070
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Lead and Zinc Naturally Enriched in Alpine Soils
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Weathering of bedrock and pedogenic processes can result in elevated heavy metal concentrations in the soil. Nowack et al. describe such a case in the Swiss National Park at an altitude of about 2400 m. The concentration of lead in six soil profiles was found to be strongly dependent on the metal content in the bedrock underlying the soil. The isotopic signature of the lead clearly indicates that it is mainly of natural origin and not caused by atmospheric deposition of anthropogenic lead. In addition, zinc was very strongly enriched in the topsoil, suggesting that recycling through plant uptake and litter deposition was a dominant process in the long-term retention of this metal in the soil.
Bernd Nowack
(nowack@ito.umnw.ethz.ch)
Elevated Lead and Zinc Contents in Remote Alpine Soils of the Swiss National Park. J. Environ. Qual. 30:919–926
Related articles in JEQ:
- Phosphorus Losses in Furrow Irrigation Runoff
- D.T. Westermann, D.L. Bjorneberg, J.K. Aase, and C.W. Robbins
JEQ 2001 30: 1009-1015.
[Abstract]
[Full Text]
- Factors Affecting Alkalinity Generation by Successive Alkalinity-Producing Systems: Regression Analysis
- C.R. Jage, C.E. Zipper, and R. Noble
JEQ 2001 30: 1015-1022.
[Abstract]
[Full Text]
- Relationships between Biosolids Treatment Process and Soil Phosphorus Availability
- R.O. Maguire, J.T. Sims, S.K. Dentel, F.J. Coale, and J.T. Mah
JEQ 2001 30: 1023-1033.
[Abstract]
[Full Text]
- TurfPQ, A Pesticide Runoff Model for Turf
- Douglas A. Haith
JEQ 2001 30: 1033-1039.
[Abstract]
[Full Text]
- Aging Effects on Cadmium Transport in Undisturbed Contaminated Sandy Soil Columns
- P. Seuntjens, K. Tirez, J. Simunek, M.Th. van Genuchten, C. Cornelis, and P. Geuzens
JEQ 2001 30: 1040-1050.
[Abstract]
[Full Text]
- Biosolids Effects on Phosphorus Retention and Release in Some Sandy Florida Soils
- Peng Lu and George A. O'Connor
JEQ 2001 30: 1059-1063.
[Abstract]
[Full Text]
- Tree Species for Recovering Nitrogen from Dairy-Farm Effluent in New Zealand
- Jon K.F. Roygard, Brent E. Clothier, Steve R. Green, and Nanthi S. Bolan
JEQ 2001 30: 1064-1070.
[Abstract]
[Full Text]
- Effect of Flue Gas Desulfurization Residue on Plant Establishment and Soil and Leachate Quality
- Tracy Punshon, Domy C. Adriano, and John T. Weber
JEQ 2001 30: 1071-1080.
[Abstract]
[Full Text]
- Selenium Distribution and Fluxes in Intertidal Wetlands, San Francisco Bay, California
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JEQ 2001 30: 1080-1091.
[Abstract]
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- Monitoring Nitrate Leaching from Submerged Drains
- J.A. de Vos
JEQ 2001 30: 1092-1096.
[Abstract]
[Full Text]
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Monitoring Nitrate Leaching from...