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Zhu J Schmidt DR Randall GW Morey RV 《Journal of environmental science and health. Part. B》2000,35(5):585-598
The work reported indicates that there could be a potential of ground water pollution by NO3-N from turkey facilities built on both sandy and clay soils. At four different depths (30.54, 61.08, 91.62, and 122.16 cm), the NO3-N levels for the clay soil were 1572, 497, 66, and 28 ppm, and those for the sandy soil were 293, 425, 324, and 164 ppm, respectively. No significant P increases were observed but there did exist a significant increase of K in the topsoil for both clay and sandy turkey structures. The results show that swine hoop houses with less than three or four years of age may not pose a threat to groundwater pollution due to the leaching of nutrients. The only dairy feedlot sampled in this study, although it has been used for more than 20 years, did not show leaching of NO3-N and P. However, it did show a significantly elevated concentration of potassium in the topsoil, as compared to the background sample. More sites should be investigated to verify this. 相似文献
204.
Bastian RK Bachmaier JT Schmidt DW Salomon SN Jones A Chiu WA Setlow LW Wolbarst AB Yu C Goodman J Lenhart T 《Journal of environmental quality》2005,34(1):64-74
The Nuclear Regulatory Commission (NRC) announced the availability of three new documents concerning radioactive materials in sewage sludge and ash from publicly owned treatment works (POTW). One of the documents is a report presenting the results of a volunteer survey of sewage sludge and ash samples provided by 313 POTWs. The second document is a dose modeling document, using multiple exposure pathway modeling focused on a series of generic scenarios, to track possible exposure of POTW workers and members of the general public to radioactivity from the sewage sludge or ash. The third document is a guidance report providing recommendations on the management of radioactivity in sewage sludge and ash for POTW owners and operators. This paper explains how radioactive materials enter POTWs, provides criteria for evaluating levels of radioactive material in sludge and ash, and gives a summary of the results of the survey and dose modeling efforts. 相似文献
205.
Mohammadi Azam Dobaradaran Sina Schmidt Torsten C. Malakootian Mohammad Spitz Jörg 《Environmental science and pollution research international》2022,29(50):75134-75160
Environmental Science and Pollution Research - Migration of emerging contaminants (ECs) from pipes into water is a global concern due to potential human health effects. Nevertheless, a review of... 相似文献
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Dissolved uranium ((238)U(D)) was measured within the Gironde fluvial-estuarine system (France), which is well known for its heavy metal pollution and its subsequent environmental effects. Dissolved (238)U activities exhibit the highest levels and variability in the small watersheds of the Isle and Riou-Mort rivers, ascribed to low discharges and the occurrence of peculiar features (local U ore deposits; Permian layers). The major tributaries of the Gironde Estuary: Garonne, Lot and Dordogne, show rather stable (238)U(D), higher than the global mean riverine uranium activity. In the Gironde Estuary (238)U(D) behaves conservatively along the river-estuary-ocean transect. Dissolved (238)U distribution in the Gironde fluvial-estuarine system can be explained by the characteristics of considered drainage basins. There is no evidence of anthropogenic pollution. 相似文献
209.
Methane and carbon dioxide emission from two pig finishing barns 总被引:3,自引:0,他引:3
Agricultural activities are an important source of greenhouse gases. However, comprehensive, long-term, and high-quality measurement data of these gases are lacking. This article presents a field study of CH(4) and CO(2) emission from two 1100-head mechanically ventilated pig (Sus scrofa) finishing barns (B1 and B2) with shallow manure flushing systems and propane space heaters from August 2002 to July 2003 in northern Missouri. Barn 2 was treated with soybean oil sprinkling, misting essential oils, and misting essential oils with water to reduce air pollutant emissions. Only days with CDFB (complete-data-full-barn), defined as >80% of valid data during a day with >80% pigs in the barns, were used. The CH(4) average daily mean (ADM) emission rates were 36.2 +/- 2.0 g/d AU (ADM +/- 95% confidence interval; animal unit = 500 kg live mass) from B1 (CDFB days = 134) and 28.8 +/- 1.8 g/d AU from B2 (CDFB days = 131). The CO(2) ADM emission rates were 17.5 +/- 0.8 kg/d AU from B1 (CDFB days = 146) and 14.2 +/- 0.6 kg/d AU from B2 (CDFB days = 137). The treated barn reduced CH(4) emission by 20% (P < 0.01) and CO(2) emission by 19% (P < 0.01). The CH(4) and CO(2) released from the flushing lagoon effluent were equivalent to 9.8 and 4.1% of the CDFB CH(4) and CO(2) emissions, respectively. The emission data were compared with the literature, and the characteristics of CH(4) and CO(2) concentrations and emissions were discussed. 相似文献
210.
Evaluation of regression methodology with low-frequency water quality sampling to estimate constituent loads for ephemeral watersheds in Texas 总被引:1,自引:0,他引:1
Water quality regulation and litigation have elevated the awareness and need for quantifying water quality and source contributions in watersheds across the USA. In the present study, the regression method, which is typically applied to large (perennial) rivers, was evaluated in its ability to estimate constituent loads (NO(3)-N, total N, PO(4)-P, total P, sediment) on three small (ephemeral) watersheds with different land uses in Texas. Specifically, regression methodology was applied with daily flow data collected with bubbler stage recorders in hydraulic structures and with water quality data collected with four low-frequency sampling strategies: random, rise and fall, peak, and single stage. Estimated loads were compared with measured loads determined in 2001-2004 with an autosampler and high-frequency sampling strategies. Although annual rainfall and runoff volumes were relatively consistent within watersheds during the study period, measured annual nutrient and sediment concentrations and loads varied considerably for the cultivated and mixed watersheds but not for the pasture watershed. Likewise, estimated loads were much better for the pasture watershed than the cultivated and mixed landuse watersheds because of more consistent land management and vegetation type in the pasture watershed, which produced stronger correlations between constituent loads and mean daily flow rates. Load estimates for PO(4)-P were better than for other constituents possibly because PO(4)-P concentrations were less variable within storm events. Correlations between constituent concentrations and mean daily flow rate were poor and not significant for all watersheds, which is different than typically observed in large rivers. The regression method was quite variable in its ability to accurately estimate annual nutrient loads from the study watersheds; however, constituent load estimates were much more accurate for the combined 3-yr period. Thus, it is suggested that for small watersheds, regression-based annual load estimates should be used with caution, whereas long-term estimates can be much more accurate when multiple years of concentration data are available. The predictive ability of the regression method was similar for all of the low-frequency sampling strategies studied; therefore, single-stage or random strategies are recommended for low-frequency storm sampling on small watersheds because of their simplicity. 相似文献