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251.
Many of today's most urgent environmental problems arise from increasing volumes of worldwide production and consumption and the associated use of natural resources, including renewable and non-renewable raw materials, energy, water and land. Solid indicators to measure different dimensions of anthropogenic resource use are essential for designing appropriate policy measures for a sustainable management of these resources. Based on a brief review of the current state of the art of resource use indicators, this paper suggests a new set of complementary resource use indicators, combining existing measures for resource use. The suggested indicator set covers the core resource input categories of materials, water and land area and includes the output category of greenhouse gas emissions. This set can be applied consistently from the micro level of products and companies up to the macro level of countries and world regions. All suggested indicators take a life-cycle wide perspective on production and consumption activities. This set of indicators deals with the issue of the overall scale of the human production and consumption system. It can be regarded as the general indicator framework, based on which more specific indicators, for example, on different environmental impacts related to natural resource use, can be calculated.  相似文献   
252.
The production of energy crops in Germany is a growing agronomic sector and is expected to occupy a substantial share of farmland in the near future. At the same time, there are concerns that energy crops might cause increased nitrogen pollution of soil water, surface water and groundwater. Therefore, the Federal State of Saxony, Germany, funded a study on potential effects of an intensified cultivation of energy crops. In frame of this study, we used the Web GIS-based model STOFFBILANZ to simulate N leaching from the rooting zone and N loads of surface water for a reference scenario and an energy crop scenario. For the reference scenario, we used data representing the crop cultivation for the year 2005 at municipality level. We found that the total loads for N leaching from the rooting zone of cropland are highest for the loess region (8,067 t year?1), followed by mountainous region (6,797 t year?1) and lowland (5,443 t year?1). However, highest N fluxes in the leachate from rooting zones have been simulated for lowland (40.6 kg ha?1 year?1) and mountainous region (37.1 kg ha?1 year?1), while nitrate concentrations of leachate were highest for the lowland (101.8 mg l?1). In terms of diffuse N input into surface water, the mountainous region is the most important source area (total N load 6,380 t year?1, flux 34.6 kg ha?1 year?1). Retention by in-stream processes accounts for 15 % (3,784 t year?1) of the total N load leaving the study area (25,136 t year?1). In the 2020 energy crop scenario, shares of rape and silage maize (id., ensiled corn) were limited for each municipality to a maximum of 25 and 33 %, respectively. The conversion of grasslands to crop farming was not allowed. Under these conditions, we found slight to substantial reductions of nitrogen loads for leachate from the rooting zone and for surface waters. The simulated reduction depends strongly on local conditions. Only small reductions (ca. 4–8 %) were found for the lowlands and mountainous regions of Saxony, while reductions for the loess region were substantial (ca. 22 %). A major outcome of our study is that the cultivation of energy crops might reduce N loss if certain preconditions are assumed, for example, without conversion of grasslands to crop farming. However, effects might vary widely depending on local conditions.  相似文献   
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254.
To include consequences emanating from former military sites on the drinking water supply, a catalog of criteria has been developed which permits the determination and assessment of the hazards in general and their impact on human health in particular. The assessment criteria correspond to the special requirements and standards for drinking water hygiene and protection in Germany. The criterion catalog is a completion module to the usual praxis and existing conceptions, and has proved its practical value in the initial assessment of military sites in the new federal states of Germany. The scheme is a control instrument suitable for obtaining an assessment concerning the extent to which drinking-water resources are and will be affected by former waste disposal and other contaminated sites at the present and in the future.  相似文献   
255.
Abstract: The Italian wolf ( Canis lupus ) population has declined continuously over the last few centuries and become isolated as a result of the extermination of other populations in central Europe and the Alps during the nineteenth century. In the 1970s, approximately 100 wolves survived in 10 isolated areas in the central and southern Italian Apennines. Loss of genetic variability, as suggested by preliminary studies of mitochondrial DNA (mtDNA) sequences, hybridization with feral dogs, and the illegal release of captive, non-native wolves are considered potential threats to the viability of the Italian wolf population. We sequenced 546 base pairs of the mtDNA control region in a comprehensive set of Italian wolves and compared them to those of dogs and other wolf populations from Europe and the Near East. Our data confirm the absence of mtDNA variability in Italian wolves: all 101 individuals sampled across their distribution in Italy had the same, unique haplotype, whereas seven haplotypes were found in only 26 wolves from an outbred population in Bulgaria. Most haplotypes were specific either to wolves or dogs, but some east European wolves shared haplotypes with dogs, indicative of hybridization. In contrast, neither hybridization with dogs nor introgression of non-native wolves was detected in the Italian population. These findings exclude the introgression of dog genes via matings between male wolves and female dogs, the most likely direction of hybridization. The observed mtDNA monomorphism is the possible outcome of random drift in the declining and isolated Italian wolf population, which probably existed at low effective population size during the last 100–150 years. Low effective population size and the continued loss of genetic variability might be a major threat to the long-term viability of Italian wolves. A controlled demographic increase, leading to recolonization of the historical wolf range in Italy, should be enforced.  相似文献   
256.
257.
Determination of the nature and extent of the connection between groundwater and surface water is of paramount importance to managing water supplies. The development of analyses that detail the surface water‐groundwater system may lead to more effective utilization of available water. A tool was developed to help determine the effects of groundwater and surface water interactions. The software tool includes two graphic user interfaces to allow full compatibility with numerical MODFLOW groundwater models. This case study shows the tool, in conjunction with MODFLOW groundwater models and carefully designed scenarios, can successfully calculate the rates of stream‐groundwater interactions, thereby providing the basis for designating management areas with the most significant hydrologic impact. This tool can be applied in other regions with similar settings and needs for integrated water management.  相似文献   
258.
The occurrence of a large number of diverse arsenic species in the environment and in biological systems makes it important to compare their relative toxicity. The toxicity of arsenic species has been examined in various cell lines using different assays, making comparison difficult. We report real-time cell sensing of two human cell lines to examine the cytotoxicity of fourteen arsenic species: arsenite(As~Ⅲ), monomethylarsonous acid(MMA~Ⅲ) originating from the oxide and iodide forms, dimethylarsinous acid(DMA~Ⅲ), dimethylarsinic glutathione(DMAG~Ⅲ), phenylarsine oxide(PAO~Ⅲ), arsenate(AsV), monomethylarsonic acid(MMA~Ⅴ), dimethylarsinic acid(DMA~Ⅴ),monomethyltrithioarsonate(MMTTA~Ⅴ), dimethylmonothioarsinate(DMMTA~Ⅴ),dimethyldithioarsinate(DMDTA~Ⅴ), 3-nitro-4-hydroxyphenylarsonic acid(Roxarsone, Rox),and 4-aminobenzenearsenic acid(p-arsanilic acid, p-ASA). Cellular responses were measured in real time for 72 hr in human lung(A549) and bladder(T24) cells. IC50 values for the arsenicals were determined continuously over the exposure time, giving rise to IC50 histograms and unique cell response profiles. Arsenic accumulation and speciation were analyzed using inductively coupled plasma-mass spectrometry(ICP-MS). On the basis of the 24-hr IC50 values, the relative cytotoxicity of the tested arsenicals was in the following decreasing order: PAO~Ⅲ? MMA~Ⅲ≥ DMA~Ⅲ≥ DMAG~Ⅲ≈ DMMTA~Ⅴ≥ As~Ⅲ? MMTTA~Ⅴ AsV DMDTA~ⅤDMA~Ⅴ MMA~Ⅴ≥ Rox ≥ p-ASA. Stepwise shapes of cell response profiles for DMA~Ⅲ, DMAG~Ⅲ,and DMMTA~Ⅴcoincided with the conversion of these arsenicals to the less toxic pentavalent DMA~Ⅴ. Dynamic monitoring of real-time cellular responses to fourteen arsenicals provided useful information for comparison of their relative cytotoxicity.  相似文献   
259.
260.
Nile tilapia (Oreochromis niloticus) were fed by diets supplemented with cyanobacteria containing in part the cyanotoxin microcystin-LR (MC-LR) to determine the potential impacts on detoxification. Four different diets were prepared based on a commercial diet: (1) control, (2) MC-5% (containing 5% dried Microcystis sp. biomass with 4.92 μg MC-LR g(-1) diet), (3) MC-20% (containing 20% dried Microcystis sp. biomass with 19.54 μg MC-LR g(-1) diet), and (4) Arthr-20% (containing 20% dried Arthrospira sp. biomass without MC-LR). Blood and liver samples were taken after one, 7, and 28 days and protein has been determined in plasma and liver. In the liver, impacts on detoxification were measured by glutathione-S-transferase (GST) activities and gene expression of multi drug resistance protein (MDRP). Plasma protein did not change between all four diets at any sampling time whereas liver protein was significantly elevated already after one day in Arthr-20% and after 28 days in both, MC-20% and Arthr-20%. Biochemical measurements of GST activities revealed no significant impact at any sampling time. In order to characterize the potential effect of MC-LR on MDRP, RT-qPCR method was established. However, as for GST activities no significant changes in MDRP gene expression have been observed. Thus, in summary, oral exposure of MC-LR containing cyanobacteria to Nile tilapia via feed ingestion did not impact significantly detoxification in liver concerning GST activities and MDRP expression despite biochemical composition concerning liver protein was significantly elevated by the diets containing 20% cyanobacteria biomass, regardless whether they contained MC-LR or not.  相似文献   
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