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91.
The Mediterranean and neighboring countries are already experiencing a broad range of natural and man-made threats to water security. According to climate projections, the region is at risk due to its pronounced susceptibility to changes in the hydrological budget and extremes. Such changes are expected to have strong impacts on the management of water resources and on key strategic sectors of regional economies. Related developments have an increased capacity to exacerbate tensions, and even intra- and inter-state conflict among social, political, ecological and economic actors. Thus, effective adaptation and prevention policy measures call for multi-disciplinary analysis and action.This review paper presents the current state-of-the-art on research related to climate change impacts upon water resources and security from an ecological, economic and social angle. It provides perspectives for current and upcoming research needs and describes the challenges and potential of integrating and clustering multi-disciplinary research interests in complex and interwoven human-environment systems and its contribution to the upcoming 5th assessment report of the IPCC.  相似文献   
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This paper describes concerns about the documentation, dissemination and use of lessons learned from mishap investigations, impediments posed by current practices, and opportunities for improvement. Lessons are presently developed, documented and stored primarily in narrative form and relational databases, and disseminated in many forms and media, including the Internet. Current practices pose many impediments to maximized development, dissemination and use. Investigation process research and new data concepts behind the Semantic Web, exploited elsewhere, offer potential opportunities to overcome these impediments. To exploit these opportunities, formation of a working group to develop an improved Semantic Web-friendly mishap investigation lessons learning system is proposed. An example illustrating an alternative approach is described to support a reasonable expectation that an alternative lessons learning system could be developed.  相似文献   
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The Wanjiazhai Water Transfer Project, now under development by the Shanxi Province of China with World Bank assistance, is a pioneering undertaking providing massive integrated water transfer, to enable the 'parched' regions of northern China to be able to survive. The Wanjiazhai project will deliver some 1.76 million m3/day of fresh water from the Wanjiazhai Reservoir on the Yellow River, by means of a series of pumping stations tunnels, and other components, over a distance of some 285 km to the City of Taiyuan, which is the hub of one of China's major industrial zones. Due to the continuing growth of population and of associated industry and agriculture, the local water resources have become totally overutilised, although extensive recycling for industry and irrigation occurs. The current sustainability of the groundwater resources is seriously threatened, for the present water shortage is 0.43 million m3/day. In addition, because of the large production of pollutant discharges with insufficient attention to waste management, the local river has become grossly polluted. The only answer is a massive importation of water, which is the first step in the project now underway.The focus of the present paper is to examine how the overall project will incorporate essential components to ensure that the expensive imported water will be wisely utilized. To manage this problem the overall project includes a number of special components including: (i) a critical assessment of the new total water resources availability and its allocation between various users, including a pricing structure which assigns equal value to both local and imported water supplies, (ii) an optimization of use of clean technologies and of recycling by industries, as well as improved waste treatment, including the establishment of a financial revolving fund to assist in achieving these goals, (iii) a substantial strengthening of the community/regional water pollution control management operations, with adequate funding, so as to upgrade the municipal wastewater treatment system to restore the river to acceptable water quality levels and, (iv) the recharging of the groundwater basins with treated sewage effluents, plus recharging using floodwater runoff during the rainy seasons.  相似文献   
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Appropriate assessment of firm sustainability facilitates actor-driven processes towards sustainable development. The methodology in this paper builds further on two proven methodologies for the assessment of sustainability performance: it combines the sustainable value approach with frontier efficiency benchmarks. The sustainable value methodology tries to relate firm performance to the use of different resources. This approach assesses contributions to corporate sustainability by comparing firm resource productivity with the resource productivity of a benchmark, and this for all resources considered. The efficiency is calculated by estimating the production frontier indicating the maximum feasible production possibilities. In this research, the sustainable value approach is combined with efficiency analysis methods to benchmark sustainability assessment. In this way, the production theoretical underpinnings of efficiency analysis enrich the sustainable value approach. The methodology is presented using two different functional forms: the Cobb–Douglas and the translog functional forms. The simplicity of the Cobb–Douglas functional form as benchmark is very attractive but it lacks flexibility. The translog functional form is more flexible but has the disadvantage that it requires a lot of data to avoid estimation problems. Using frontier methods for deriving firm specific benchmarks has the advantage that the particular situation of each company is taken into account when assessing sustainability. Finally, we showed that the methodology can be used as an integrative sustainability assessment tool for policy measures.  相似文献   
96.
MtDNA analyses were employed to examine the species identification of three preserved museum sturgeon specimens from the River Guadalquivir, two of which were originally described as Acipenser sturio L., 1758 by Hernando (1975; Doñana, Acta Vertd 2: 263–264). Later the same two specimens were identified as A. naccarii Bonaparte, 1836 by Garrido-Ramos et?al. (1997; Mar Biol 129: 33–39) on the basis of morphometric and nuclear DNA analyses. Three different laboratories using independent techniques were unsuccessful in extracting authentic DNA from tissue samples from the three specimens and in obtaining any verifiable PCR product. We cannot confirm the previous molecular identification of two of these specimens by Garrido-Ramos et?al. as A. naccarii. We suggest that these specimens are indeed A. sturio.  相似文献   
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对美洲热带湿润低地次生林管理的看法   总被引:7,自引:0,他引:7  
在休闲农地上重新长出的次生林,尽管广被忽视,仍是美洲热带低地重要的景观单元.这些在私人占用土地中"新"的森林资源不是来源于境况较好农民的非持续性的大牧场就是来源于资源贫乏农民的耕种/休闲体系.  相似文献   
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