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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   
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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   
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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   
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Background, aim and scope The first two articles of this series (Hornsmann et al. 2008; Weustermann et al. 2009) comprised how the Ecological Land Classification of Europe (ELCE) was calculated. Moreover several ecological classes were described exemplarily. In this part 3 of the series the ELCE is compared with two European ecoregionalisations at several levels of differentiation. These are the Digital Map of European ecological regions (DMEER) and the Environmental Stratification of Europe (EnS). In addition the ELCE was opposed to the ecoregionalisation of Germany. The alignment was carried out both functionally and statistically and served as a basis for the examination of the functional consistency of the ELCE. Materials and methods The ecological land classifications were described concerning their input data, the method of derivation and the intended use. The ELCE and the selected three ecoregionalisations were intersected in a GIS and crosstabulated with regard to the acreage of each polygon. These cross tabulations were performed by listing the percentage of ecoregions of e.?g. DMEER to the ecological classes of the ELCE (EC) and vice versa. The similarity of the compared ecoregions was estimated by means of statistics. Results The comparisons show high rates of similarity of the ELCE to the European land classifications. The mean overlap of the EC with the classes of the DMEER is 84 and 69?% vice versa. The EC are covered by the strata of the EnS with 67 and 72?%, respectively. In Germany, ELCE reflects the most important ecological conditions. The mean overlap of the ecoregions in this case is 75 and 80?% vice versa. Discussion The classes of the DMEER show a better overlap of the EC as vice versa due to their larger spatial extent. The main difference between the ELCE and the EnS is based on the procedure of the derivation of the regionalisations. While the classes of the EnS are more differentiated in the South of Europe, the ecoregions of ELCE are smaller and more subdivided in the middle of Europe. The high overlap between the ELCE and the ecoregionalisation of Germany can be indicative for the good account of the ecological structures of the ELCE in the European dimension. Conclusions The ELCE is functionally plausible and a useful complement to the existing land classifications of Europe. Nevertheless, it cannot substitute land classifications on the national level calculated with more detailed input data. The ELCE can be used testing the representativity of environmental monitoring networks in Europe. Recommendations In future, the ELCE should be compared with other national landscape classifications. A new calculation of ELCE would only be useful after the development of a highly powerful derivation method and on the basis of more detailed input data. Moreover, due to the observed climate change in the past 20 years, up-to-date data on climate should be used for the calculations. Perspectives The ELCE could be proven to be functionally consistent. Therefore the fourth article will focus on the investigation of the landscape representativity of environmental monitoring networks on the basis of the ELCE.  相似文献   
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