bluuebunny/crossref_metadata_2025_split huggingface dataset:
Occurrence of Metals in Soil and Ground Water Near Chromated Copper Arsenate–Treated Utility Poles
Authors: Zagury Gérald J. , Samson Réjean , Deschênes Louise 
Published: August 2012

ABSTRACTTo thoroughly investigate the metal contamination around chromated copper arsenate (CCA)/polyethylene glycol (PEG)–treated utility poles, a total of 189 soil samples obtained from different depths and distances near six treated poles in the Montreal area (Canada) were analyzed for Cu, Cr, and As content. Various soil physicochemical properties were also determined. Ground water samples collected below the poles were analyzed for metals and bioassays with Daphnia magna were conducted. Generally, sandy soils had lower contaminant levels than clayey and organic soils. Copper concentrations in soil were highest followed by As and Cr. The highest Cu (1460 ± 677 mg kg−1), As (410 ± 150 mg kg−1), and Cr (287 ± 32 mg kg−1) concentrations were found at the ground line and immediately adjacent to the pole. Contaminant levels then decreased with distance, approaching background levels within 0.1 m from the pole for Cr and 0.5 m for Cu and As. Chromium and Cu levels generally approached background levels at a depth of 0.5 m. Average As content near the pole on all study sites was three to eight times higher than Quebec's Level C criterion (50 mg kg−1), although it dropped to 31 mg kg−1 at 0.1 m. Results also showed that As persisted up to 1 m in soil depth (17–54 mg kg−1). Copper and Cr concentrations in ground water samples were always <1.000 mg L−1 and <0.05 mg L−1, respectively and Cr(VI) was <0.02 mg L−1 One sample contained an As concentration > 0.025 mg L−1 but bioassays showed that, overall, ground water had a low ecotoxic potential.
Weathering of Lead Bullets and Their Environmental Effects at Outdoor Shooting Ranges
Authors: Cao Xinde , Ma Lena Q. , Chen Ming , Hardison Donald W. , Harris Willie G. 
Published: August 2012

ABSTRACTLead contamination at shooting range soils is of great environmental concern. This study focused on weathering of lead bullets and its effect on the environment at five outdoor shooting ranges in Florida, USA. Soil, plant, and water samples were collected from the ranges and analyzed for total Pb and/or toxicity characteristic leaching procedure (TCLP) Pb. Selected bullet and berm soil samples were mineralogically analyzed with X‐ray diffraction and scanning electron microscopy. Hydrocerussite [Pb3(CO3)2(OH)2] was found in both the weathered crusts and berm soils in the shooting ranges with alkaline soil pH. For those shooting ranges with acidic soil pH, hydrocerussite, cerussite (PbCO3), and small amount of massicot (PbO) were predominantly present in the weathered crusts, but no lead carbonate mineral was found in the soils. However, hydroxypyromorphite [(Pb10(PO4)6(OH)2] was formed in a P‐rich acidic soil, indicating that hydroxypyromorphite can be a stable mineral in P‐rich shooting range soil. Total Pb and TCLP Pb in the soils from all five shooting ranges were significantly elevated with the highest total Pb concentration of 1.27 to 4.84% (w/w) in berm soils. Lead concentrations in most sampled soils exceeded the USEPA's critical level of 400 mg Pb kg−1 soil. Lead was not detected in subsurface soils in most ranges except for one, where elevated Pb up to 522 mg kg−1 was observed in the subsurface, possibly due to enhanced solubilization of organic Pb complexes at alkaline soil pH. Elevated total Pb concentrations in bermudagrass [Cynodon dactylon (L.) Pers.] (up to 806 mg kg−1 in the aboveground parts) and in surface water (up to 289 μg L−1) were observed in some ranges. Ranges with high P content or high cation exchange capacity showed lower Pb mobility. Our research clearly demonstrates the importance of properly managing shooting ranges to minimize adverse effects of Pb on the environment.
Managing Material Transfer and Nutrient Flow in an Agricultural Watershed
Authors: Nord E. A. , Lanyon L. E. 
Published: August 2012

ABSTRACTPlace‐based resource management, such as watershed or ecosystem management, is being promoted to replace the media‐focused approach for achieving water quality protection. We monitored the agricultural area of a 740‐ha watershed to determine the nature and scale of farm material transfers, N and P balances, and farmer decisions that influenced them. Using field data and farmer interviews we found that 3 of 15 farms, emphasizing hog, dairy, or cash crops with poultry production, accounted for more than 80% of the inputs and outputs of N and P for the 362‐ha agricultural area (332 ha of managed cropland and animal facilities). Feed for hogs (38% each of total N and P) and manure applied to fields as part of the cash crop and poultry operation (28 and 38% of total N and P, respectively) were the dominant inputs. No crops grown in the watershed were fed to animals in the watershed and more manure nutrients were applied from animals outside than from those in the watershed. A strategic decision by the hog farmer to begin marketing finished hogs changed the material transfers and nutrient balances more than tactical decisions by other farmers in allocating manure to cropland. Since the components of agricultural production were not all interconnected, the fundamental assumption of place‐based management programs is not well‐suited to this situation. Alternative approaches to managing the effect of agriculture on water quality should consider the organization of agricultural production and the role of strategic decisions in controlling farm nutrient balances.
Water Quality Changes in a Polluted Stream over a Twenty‐Five‐Year Period
Authors: Stewart Jason , Skousen Jeff 
Published: August 2012

ABSTRACTThe Deckers Creek watershed in northern West Virginia (USA), containing a land area of 166 km2 (63 mi2), has a long history of industrial development and attendant environmental abuses from both land and water pollution practices. The water in Deckers Creek was sampled in 1974 at 29 locations along the main stem and resampled in 1999–2000 to determine water quality changes over this 25‐year period. Water samples were analyzed for pH, acidity, alkalinity, iron, and calcium at both times, while aluminum, manganese, zinc, and fecal coliform (FC) bacteria densities were added in 1999–2000. Water at almost all sampling points showed lower acidity and metal contents in 1999–2000 compared with 1974. Water pH increased at the mouth from 5.4 in 1974 to 6.0 in 1999–2000. Acidity and iron concentrations were decreased an average of 70% in the upper stretches of the creek. However, one major untreated point source of water from an abandoned underground mining complex continues to degrade the quality of the creek in its lower stretches. In the upper section, the water quality in Deckers Creek has improved due to decreased surface and underground coal mining activities, reclamation of abandoned and recently permitted surface mined lands, and natural healing of past land use scars from timbering and mining over time. The decrease in mineral extraction activities and the reclamation of disturbed lands has occurred due to the passage and enforcement of water quality and land reclamation laws and regulations. More time and additional reclamation projects will continue to enhance the water quality in the creek. Improved water chemistry in the majority of the creek, however, shows the previously unnoticeable biological contamination from sewage inputs.
Evaluation of an Acid Ammonium Oxalate Extraction to Determine Fluoride Resident Concentrations in Soils
Authors: Bégin Louis , Fortin Josée 
Published: August 2012

ABSTRACTFluoride depositions near aluminum smelters and other fluoride‐emitting plants can lead to fluoride accumulation in soils, which constitutes a risk for ground water contamination. This study was conducted to investigate the capacity of a 0.2 M acid ammonium oxalate solution to selectively and quantitatively extract fluoride accumulated in soils. The recovery of fluoride added to three soils was evaluated following 7‐ to 28‐d incubations. Oxalate extraction was also compared with a total fluoride extraction method, using oxalate‐extractable fluoride (Fox) and total fluoride (Ftot) accumulation profiles derived from column percolation experiments. To determine low‐level fluoride concentrations without interference from high Al and Fe concentrations, an adapted ion chromatography method was used. Following soil incubations, oxalate extracted 42 to 86% of added fluoride. Recovery varied between soils and, in one soil, increased with added fluoride concentration. Recovery was unaffected by incubation time. Maximum recovery was obtained in a soil high in amorphous Fe and Al, low in clay, and free of carbonate. Lower recoveries were obtained in soils with higher clay or carbonate contents. Only 4 to 8% of Ftot was extracted in untreated samples using Fox, which suggests a high selectivity of this method for added fluoride. In percolation experiments, the use of Fox reduced considerably the background noise associated with Ftot for the evaluation of fluoride accumulation profiles. Because of its high selectivity and despite incomplete fluoride recovery, the use of Fox to determine fluoride resident concentrations in soils may improve environmental monitoring of fluoride accumulation and movement in contaminated soils.
Polyacrylamide Distribution in Columns of Organic Matter–Removed Soils following Surface Application
Authors: Lu Jianhang , Wu Laosheng 
Published: August 2012

ABSTRACTKnowledge of how polyacrylamide (PAM) penetrates and distributes in a soil profile after application in irrigation water is important for understanding PAM conditioning depth and evaluating its environmental effects. Little is known, however, about PAM distribution in soil because of the difficulty in quantifying PAM content in natural soils. By using a recently modified substrate‐borne PAM quantification method, PAM distribution in columns of organic matter–removed soils was determined. Results showed that penetration of PAM into the soil was affected by salt level of irrigation water, soil texture, initial soil water content, water application method, and other factors. Polyacrylamide penetration depth was about one‐eighth to one‐half of the water penetration depth, with a particularly high PAM retention in the top few centimeters of the soil. Under different experimental conditions, the PAM retained in the top 0 to 2 cm of soil ranged from 16 to 95% of the total applied amount. More favorable solution–soil contact conditions, longer solution–soil contact time, and lower initial soil moisture caused much more PAM retention in the top few centimeters of the soil. High sorptive affinity of PAM on soil is the main reason for its low penetration into the soil. Although these results were not obtained from natural soils, they are still helpful in improving our understanding of PAM transport behavior in soils.
Swine Effluent Irrigation Rate and Timing Effects on Bermudagrass Growth, Nitrogen and Phosphorus Utilization, and Residual Soil Nitrogen
Authors: Adeli A. , Varco J. J. , Rowe D. E. 
Published: August 2012

ABSTRACTMaximizing utilization of effluent nutrients by forage grasses requires a better understanding of irrigation rate and timing effects. This study was conducted in 1998 and 1999 on a Vaiden silty clay (very‐fine, smectitic, thermic Aquic Dystrudert) soil to determine the effects of swine lagoon effluent irrigation rate and timing on bermudagrass [Cynodon dactylon (L.) Pers.] growth, nitrogen (N) and phosphorus (P) recovery, and postseason soil profile NO−3–N. Treatments consisted of swine effluent irrigation at the rates of 0, 5, 10, 15, and 20 ha‐cm. Two additional treatments included 2.5 ha‐cm applied on 1 September and 1 October in addition to a base summer rate of 10 ha‐cm. In both years for early to mid‐season irrigation, bermudagrass dry matter yield quadratically increased with increasing swine effluent irrigation rates. Averaged across years, effluent irrigation in October resulted in 30% less dry matter than in September. For late‐season irrigation, apparent N recovery averaged 59% less and P recovery averaged 46% less with a delay in irrigation from 1 September to 1 October. The greatest quantity of soil NO−3–N was associated with both the greatest effluent rate and October irrigation treatments. Minimal yield benefit was obtained when effluent was applied at rates greater than 10 ha‐cm during the summer months. Late‐season irrigation, especially after 1 October for areas with similar climatic conditions, should be avoided to maximize synchronization of nutrient availability with maximum growth rates to minimize potential offsite movement of residual soil N and P.
Properties of Several Fly Ash Materials in Relation to Use as Soil Amendments
Authors: Pathan S. M. , Aylmore L. A. G. , Colmer T. D. 
Published: August 2012

ABSTRACTFly ash samples from five power stations in Western Australia and Queensland, and two soils used for horticulture in Western Australia, were evaluated for a series of physical and chemical properties. Soils were comprised primarily of coarse sand‐sized particles, whereas most of the fly ashes were primarily fine sand‐ and silt‐sized particles. Hydraulic conductivities in the fly ashes were 105‐ to 248‐fold slower than in the soils. The water‐holding capacities of fly ashes at “field capacity” were three times higher than those of the soils. Extractable P in the fly ashes (except Tarong and Callide) were 20‐ to 88‐fold higher than in the soils. The pH showed considerable variation among the different sources of fly ash, with samples from Muja being the most acidic (pH = 3.8; 1:5 in CaCl2 extract) and from Gladstone the most alkaline (pH = 9.9). The toxicity characteristic leaching procedure (TCLP) values indicate that the potential for release of trace elements from the fly ashes was well below regulatory levels. When applied at sufficient rates (e.g., to achieve 10% w/w in surface layers) to sandy soils, fly ash altered texture and increased water‐holding capacity. Depending on the source of fly ash used, such amendments could also provide P and aid nutrient retention by increasing the phosphorus retention index (PRI) and/or cation exchange capacity (CEC). The considerable variability in physical and chemical properties among the fly ash samples evaluated in the present study supports the notion that field trials are essential to the future development of soil amendment strategies making use of any particular source of fly ash.
Nutrient and Hydrology Effects on Soil Respiration in a Northern Everglades Marsh
Authors: DeBusk W. F. , Reddy K. R. 
Published: August 2012

ABSTRACTMicrobial respiration in peat and overlying plant litter, as influenced by water level and phosphorus enrichment, was evaluated for an Everglades (Florida, USA) marsh ecosystem by measuring CO2and CH4release from soil–water microcosms. Intact cores of peat, overlying plant litter, and surface water were collected at seven locations in cattail (Typha domingensisPers.) and sawgrass (Cladium jamaicenseCrantz) stands along a phosphorus (P) enrichment gradient in Water Conservation Area 2A (WCA‐2A). Each soil–water microcosm was outfitted with a controlled air circulation system whereby outflow gas from the headspace could be analyzed for CO2and CH4to determine flux of C from the soil–water column to the atmosphere. Gaseous C flux was determined for flooded conditions (10‐cm water depth) and for water levels of 0, 5, 10, and 15 cm below the peat surface. Overall, decreasing water level resulted in significantly increased C flux, although rates were significantly higher under flooded conditions than under nonflooded, saturated‐soil conditions, presumably due to O2availability associated with algal photosynthesis within the litter layer in the water column. Carbon flux decreased significantly for sites increasingly distant from the primary hydrologic and nutrient inflows to WCA‐2A. The microcosm study demonstrated that the C turnover rate was significantly increased by accelerated nutrient loading to the marsh, and was further enhanced by decreasing water level under drained conditions. Our results also demonstrated that photosynthesis within the water column is a potentially important regulator of C mineralization rate in the litter layer of the marsh system.
Antimony Impurity in Lead Arsenate Insecticide Enhances the Antimony Content of Old Orchard Soils
Authors: Wagner Sandra E. , Peryea Frank J. , Filby Royston A. 
Published: August 2012

ABSTRACTLead arsenate was a commonly used insecticide during the first half of the 20th century, particularly in deciduous tree fruit orchards. Antimony is cotransported with As during the ore refining process and could occur as an impurity in commercial lead arsenate products. The total concentrations of As and Sb in eight soil samples collected from eight orchards located throughout central Washington State were analyzed by neutron activation analysis. Total soil Sb concentrations ranged between 0.4 and 1.5 mg kg−1, while total soil As concentration ranged from 1 to 170 mg kg−1 Total soil Sb and As concentrations were positively related. Total Pb and As concentrations in four of the soils were substantially higher than natural background, while the Sb to As concentration ratios in these soils were consistent with values measured in three lead arsenate insecticide products. These results confirm that Sb impurity is present in lead arsenate insecticide and has contributed to Sb enrichment of soils on which lead arsenate–treated plants were grown. Although higher than in uncontaminated soils from the same region, the Sb concentrations in the affected soils fall within the normal range observed worldwide and are substantially lower than values associated with impaired human or environmental health.
Leaching Characteristics of Heavy Metals from Sewage Sludge by Acidithiobacillus thiooxidans MET
Authors: Ryu H. W. , Moon H. S. , Lee E. Y. , Cho K. S. , Choi H. 
Published: August 2012

ABSTRACTAn acidophilic, sulfur‐oxidizing Acidithiobacillus thiooxidans MET bacterium was isolated from anaerobically digested, dewatered sewage sludge. This bacterium showed sulfur‐oxidizing ability at both acidic and neutral conditions, and allowed metal leaching even at a high (130 g L−1) sludge solids concentration. We found that low metal leaching efficiency at high solids concentration was mainly due to an increase in buffering capacity resulting in retardation of pH reduction. Therefore, metal leaching was mainly influenced not by sludge solids concentration, but by the pH (or sulfate concentration per unit sludge mass) of the sludge solutions. The relationship between the pH of the sludge solution and the efficiency of metal leaching was obtained by quantitatively investigating the effect of pH reduction or the amount of sulfate produced per unit sludge mass on leaching of each metal. Furthermore, the relationship between total metal content in the sludge and metal leached to the solution was obtained for each metal. Such a relationship allowed estimation of leachable metal at various amounts of total metal content in sludge.
Reduction of Arsenic Uptake by Lettuce with Ferrous Sulfate Applied to Contaminated Soil
Authors: Warren G. P. , Alloway B. J. 
Published: August 2012

ABSTRACTSoil contamination by arsenic (As) presents a hazard in many countries and there is a need for techniques to minimize As uptake by plants. A proposed in situ remediation method was tested by growing lettuce (Lactuca sativa L. cv. Kermit) in a greenhouse pot experiment on soil that contained 577 mg As kg−1, taken from a former As smelter site. All combinations of iron (Fe) oxides, at concentrations of 0.00, 0.22, 0.54, and 1.09% (w/w), and lime, at concentrations of 0.00, 0.27, 0.68, and 1.36% (w/w), were tested in a factorial design. To create the treatments, field‐moist soil, commercial‐grade FeSO4, and ground agricultural lime were mixed and stored for one week, allowing Fe oxides to precipitate. Iron oxides gave highly significant (P < 0.001) reductions in lettuce As concentrations, down to 11% of the lettuce As concentration for untreated soil. For the Fe oxides and lime treatment combinations where soil pH was maintained nearly constant, the lettuce As concentration declined in an exponential relationship with increasing FeSO4 application rate and lettuce yield was almost unchanged. Iron oxides applied at a concentration of 1.09% did not give significantly lower lettuce As concentrations than the 0.54% treatment. Simultaneous addition of lime with FeSO4 was essential. Ferrous sulfate with insufficient lime lowered soil pH and caused mobilization of Al, Ba, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sr, and Zn. At the highest Fe oxide to lime ratios, Mn toxicity caused severe yield loss.
Nitrate Distributions and Source Identification in the Abbotsford–Sumas Aquifer, Northwestern Washington State
Authors: Mitchell Robert J. , Babcock R. Scott , Gelinas Sharon , Nanus Leora , Stasney David E. 
Published: August 2012

ABSTRACTThe Abbotsford–Sumas Aquifer is a shallow, predominantly unconfined aquifer that spans regions in southwestern British Columbia, Canada and northwestern Washington, USA. The aquifer is prone to nitrate contamination because of extensive regional agricultural practices. A 22‐month ground water nitrate assessment was performed in a 10‐km2 study area adjacent to the international boundary in northwestern Washington to examine nitrate concentrations and nitrogen isotope ratios to characterize local source contributions from up‐gradient sources in Canada. Nitrate concentrations in excess of 10 mg nitrate as nitrogen per liter (mg N L−1) were observed in ground water from most of the 26 domestic wells sampled in the study area, and in a creek that dissects the study area. The nitrate distribution was characteristic of nonpoint agricultural sources and consistent with the historical documentation of agriculturally related nitrate contamination in many parts of the aquifer. Hydrogeologic information, nitrogen isotope values, and statistical analyses indicated a nitrate concentration stratification in the study area. The highest concentrations (>20 mg N L−1) occurred in shallow regions of the aquifer and were linked to local agricultural practices in northwestern Washington. Nitrate concentrations in excess of 10 mg N L−1 deeper in the aquifer (>10 m) were related to agricultural sources in Canada. The identification of two possible sources of ground water nitrate in northwestern Washington adds to the difficulty in assessing and implementing local nutrient management plans for protecting drinking water in the region.