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941.
942.
In this paper, we explore how scenarios of future water withdrawals in a river basin are influenced by scale-dependent quantifications of the driving forces for two global-scale storylines. Either global-scale information or region-specific information is used to do the quantifications. In addition, we analyze the impact of including or not some restricted regional-scale information in the employed water use model. To develop scenarios of water withdrawals in the German part of the Elbe River basin, we applied the modules for domestic, thermoelectric power and manufacturing water use of the global water model WaterGAP, using scale-dependent driving forces scenarios and other scale-dependent model input. In the global-scale quantitative interpretations of the storylines of the IPCC SRES scenarios A1 and B2, all major driving forces of water withdrawals in the basin—population, thermoelectric power production and industrial gross domestic product—show vigorous increases between 2000 and 2025, while from the regional perspective, smaller increases but mostly decreases appear to be plausible. These discrepancies are partly due to the fact that for the global-scale interpretations only the historic developments until 1990 were taken into account, and not until 2000 as in the regional case. The resulting scenarios of sectoral water withdrawals in 2025 differ strongly between the two scale-dependent interpretations of the storylines, with the global one leading to much higher absolute water withdrawals and much lower withdrawal decreases between 2000 and 2025. Therefore, for regional assessments of water withdrawals, we recommend to embed the scenario analysis in global-scale storylines by performing regional-scale quantifications of the global qualitative driving forces scenarios, based on a limited amount of region-specific information.  相似文献   
943.
Spatial proximity of emissions sources to receptors may affect sensitivity to potential adverse human health effects. This research investigates whether receptor sensitivity to the location of emission sources can be utilized efficiently to minimize health risk in selecting sites for industrial enterprises, thermal electric stations, etc. A sensitivity function that is independent of the location of pre-existing emission sources is derived and applied to Minsk, Belarus. The function estimates exposures based on weather and climatic conditions as well as the distribution of population density at a given locality. Arraying prospective sites based on their sensitivity function magnitude provides a technique for minimizing health risk based on receptor sensitivity to the spatial proximity of atmospheric emissions sources.  相似文献   
944.
945.
A total of 65 operators involved in lichen mapping studies in central and northwestern Italy underwent quality control tests during five lichen biomonitoring workshops organized between 1999and 2000. The results showed that 75% quantitative accuracy and90% quantitative precision can be regarded as satisfactory levels for lichen biodiversity data; 65% proved to be sufficientfor accuracy of taxonomic identification in the field. Average correct assignment of the interpretative naturality/alteration class was only 48.7%. The results indicated the need for taxonomic training.  相似文献   
946.
947.
948.
949.
The biokinetics of 134Cs and 241Am in mussel species contaminated through water pathway has been studied under laboratory conditions. At equilibrium, the concentration factors for 134Cs and 241Am in small and large mussels were 2.80 and 2.57 and 200 and 150, respectively. The concentration factor of 134Cs in soft parts of the mussels was significantly high than whole body and shell tissue. However, the concentration factors of 241Am in soft parts and shell tissue samples were found to have similar rates. The depuration kinetics of the radionuclides were described by two-component exponential models. The biological half-lives at slow components between small and large mussels did not change significant, and were found to be 46.8-46.5 and 72.2-75.3 days for 134Cs and 241Am. The depuration kinetics of 134Cs and 241Am in soft parts described a single-component exponential model and the biological half-lives were found to be 29.4 and 41.1 days, respectively.  相似文献   
950.
Nonylphenols and nonylphenol-ethoxylates were detected in the water and sediment samples from the German Bight of the North Sea. Additionally bis (4-chlorophenyl)-sulfone and linear alkylbenzenesulfonates (LAS) were detected in marine waters. Proof of identification is given by comparison of spectral and chromatographic data from the compounds in sample extracts to those obtained from pure standards. In extracts obtained from water samples taken in 1990 and 1995 the concentrations of nonylphenols and bis-(4-chlorophenyl)-sulfone were compared for each year. The concentrations of nonylphenols in seawater varied from 0.7 to 4.4 ng/l while in the Elbe estuary about 33 ng/l were found. In water samples taken in 1998 nonylphenol-polyethoxylates could not be determined, whereas LAS concentrations of 30 ng/l were confirmed by HPLC-MS/MS. The concentrations of bis (4-chlorophenyl)-sulfone ranged from 0.18 to 2.2 ng/l. In sediment samples LAS concentrations of 39-109 ng/g dry weight were determined.  相似文献   
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