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The study was conducted to test the hypothesis that the regional variability of nitrogen (N) and metal accumulations in terrestrial ecosystems are due to historical and recent ways of landuse. To this end, two regions of Central Europe were selected for investigation: the Weser-Ems Region (WER) and the Euro Region Nissa (ERN). They were assumed to have land use-specific accumulation profiles. Thus, the metal and N accumulations in both regions were examined by means of geostatistically based comparative moss analysis. The sampling and chemical analysis of mosses were conducted in accordance with the convenient guidelines and methods, respectively. The spatial representativity of the sampling sites was computed by means of a land classification which was calculated for Europe by means of classification trees and GIS-techniques. The differences of deposition loads were tested for statistical significance with regard to time and space. The measurement values corroborated the decline of metal accumulation observed since the beginning of the European Metals in Mosses Surveys in 1990. The metal loads of the mosses in the ERN exceeded those in the WER significantly. The opposite holds true for the N concentrations: those in the WER were significantly higher than those in the ERN. The reduction of emissions from power plants, factories and houses was strongly correlated with the decline of deposition and bioaccumulation of metals. As proved by the European Metals in Mosses Surveys, this tendency is due to successful environmental policies. But no such success could be verified by monitoring the accumulation of N in mosses.  相似文献   
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Dialifor and methidathion were added to diluted "Zinfandel" grape concentrate at 25 ppm and dimethoate at 1.0 and 25 ppm prior to fermentation with Saccharomyces cerevisiae. The finished wine 56 days later contained 10% (2.5 ppm) of the dialifor, 46% (12 ppm) of the methidathion and 85% (21 and 0.98 ppm) of the dimethoate added to the grape must. Residues in wine stored at 24 degrees C dissipated by hydrolysis; half-lives in wine were 7 days for dialifor and methidathion and 30 days for dimethoate. Residues were unchanged in wine in frozen storage for one year. Analysis of seven commercial wines for dimethoate indicated less than 0.03 ppm dimethoate was present; identity could not be confirmed by thin-layer chromatography at this level.  相似文献   
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C7-C11 perfluorinated carboxylates (PFACs) and perfluorooctansulfonate (PFOS) were analysed in selected stretches of the River Po and its major tributaries. Analyses were performed by solid-phase extraction (SPE) with Oasis HLB cartridges and methanol elution followed by LC-MS-MS detection using 13C-labelled internal standards. High concentration levels ( approximately 1.3 microg l(-1)) of perfluorooctanoate (PFOA) were detected in the Tánaro River close to the city Alessandria. After this tributary, levels between 60 and 337 ng l(-1) were measured in the Po River on several occasions. The PFOA concentration close to the river mouth in Ferrara was between 60 and 174 ng l(-1). Using the river discharge flow data in m3 s(-1) at this point (average approximately 920 m3 s(-1) for the year 2006), a mass load of approximately 0.3 kg PFOA per hour or approximately 2.6 tons per year discharged in the Adriatic Sea has been calculated. PFOS concentration levels in the Po River at Ferrara were approximately 10 ng l(-1).  相似文献   
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Background, aim and scope  

European legislation stipulates that genetically modified organisms (GMO) have to be monitored to identify potential adverse environmental effects. A wealth of different types of monitoring data from various sources including existing environmental monitoring programmes is expected to accumulate. This requires an information system to efficiently structure, process and evaluate the monitoring data.  相似文献   
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Alkylphenols (APs), alkylphenol ethoxylates (APEOs), ethoxycarboxylate metabolites (APECs) and bisphenol A were determined in surface water using solid-phase extraction (SPE) followed by triple-quadrupole LC-MS-MS. APs were separated by LC from APECs using an acetonitrile-water-gradient without the addition of any buffer. Nonylphenol ethoxycarboxylates (NPECs) interfere in the detection of nonylphenols (NPs) when using an acidic mobile phase, because they produce the same MS-MS fragment ions (219>133 and 147). 4n-NP shows the characteristic transition 219>106; it is well suited as internal standard. Nonylphenol ethoxylates NPE(n)Os (n=1-17) were analysed separately in a second run by positive ionization using an ammonium acetate mobile phase. Textile industry discharges, the corresponding wastewater treatment plant (WWTP) effluents and the receiving rivers in Belgium and Italy were analysed. Among the substances investigated, NPE1C and NPE2O exhibited the highest concentrations in the water samples, up to 4.5 microg l(-1) NPE1C in a WWTP effluent and 3.6 microg l(-1) NPE2O in a river. The highest NP levels were found in the receiving rivers (max. 2.5 microg l(-1)). The predicted no-effect concentration (PNEC) for NP of 0.33 microg l(-1) for water species was frequently exceeded in the surface waters investigated, suggesting potential adverse effects to the aquatic environment.  相似文献   
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Metal contents of decomposing leaf blades, leaf sheaths and stems of common reed (Phragmites australis) were monitored by a litter bag method on the sediment of an intertidal brackish marsh in the Scheldt estuary (The Netherlands). On monthly intervals, two litter bags were retrieved from the marsh during 9 months for both leaf blades and sheaths and during 16 months for stems. All samples were dried, weighed and analysed for ash and Cd, Cu, Cr, Ni, Pb and Zn contents. Most concentrations increased considerably during the decomposition. Generally, also a very important net metal inflow into the litter bags could be observed. The inflow was highest for leaf blades. High correlations between ash contents and metal concentrations for leaf blades suggest that the increase of leaf blade metal contents can be due to physicochemical sorption of dissolved metals and an important infiltration of mud particles, which were not removed by rinsing the leaf blades with distilled water preceding the analyses. For stems, smaller amounts of inflowing ash and even outflowing ash amounts were found, which suggests that inflow of inorganic particles is not the major factor determining metal accumulation by stems on medium term. Ergosterol concentrations in stem tissue however proved to be correlated with metal contents, which suggests a significant role of fungal litter colonizers in metal accumulation. For leaf sheaths, the effects of physicochemical sorption, infiltration of mud particles and incorporation by microbial litter colonizers do not seem to be as pronounced as for stems and leaf blades.  相似文献   
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