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21.
The term “body of groundwater” represents a new administrative tool established by the water framework directive (WFD) in order to manage European groundwaters. Its practical application raises some difficulties due to unclear definitions and the large heterogeneity of European aquifers. In this work, a methodology is proposed to carry out the delineation of bodies of groundwater according to the requirements of the WFD. This methodology faces up to some of the major difficulties that can arise during the delineation, such as the identification of bodies of groundwater in multilayered aquifers, boundaries between superposed groundwater bodies, and delimitation in low permeability materials or in dismembered aquifers. In order to show its practical application, the proposed methodology is applied in a pilot Mediterranean river basin located in southern Spain. Results show that previous knowledge of the hydrogeological conditions is necessary to enable a correct delineation of groundwater bodies. Finally, alternative procedures are proposed for low permeability and small aquifers in order to reduce the number of groundwater bodies identified and simplify their overall management.  相似文献   
22.
在回顾国内外城市旅游已有文献的基础上,对国外城市旅游产品这一专项内容进行了文献述评,内容集中于城市旅游产品类型包括城市文化旅游产品、城市遗产旅游产品、城市事件旅游产品、城市夜间旅游产品和城市旅游产品,要素包括城市旅游吸引物、城市旅游设施、城市旅游服务、城市可进人性。  相似文献   
23.
Land tenure plays a primary role in sustainable development efforts. However armed conflict and its repercussions reconfigure the network of social relations upon which all land tenure systems depend. In post‐conflict settings new laws have the opportunity to address tenure issues in the context of what people are already doing ‘on the ground’, with a view to moving from the fluidity of post‐conflict situations to a more solidified and peaceful social and legal environment. However there exists a lack of tools to analyze postwar land tenure and the prospects for reconstituting tenure systems to support recovery and development. This paper uses the Sustainable Livelihoods framework to examine postwar land tenure issues in order to draw out latent opportunities within emergent informal smallholder tenure constructs which may have utility in the reconstitution of national tenure systems.  相似文献   
24.
中国古代思想家老子、庄子在生态环境伦理方面就如何协调人与自然的关系提出了许多宝贵的思想,如“天人合一”、“道法自然”、“知止”等。这些观点对我们解决二十一世纪所面临的生态环境问题具有重要的启迪意义。  相似文献   
25.
结合国内外最新研究进展,制定适合内蒙古区域特点的碳汇测算方法和评估体系框架,科学估算碳汇状况,系统分析我区不同陆地生态系统类型的碳汇大小及其机制,可提供关于我区陆地生态系统碳汇功能可信、翔实和正确的估算结果;新时期省级层面上开展陆地生态系统碳汇总量评估十分重要。  相似文献   
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ABSTRACT: By integrating literature from flood hazard research and urban economics a theoretical structure is developed to explain changes in residential land values following flood events. The negative aspects of the flood hazard are shown to be capitalized in the value of the property. It is further suggested that land values (i.e., capitalization) will vary both spatially across the floodplain and temporally depending on the frequency, severity and spatial characteristics of the flood event. Previous work in this area has not addressed the capitalization process explicitly and has not specifically examined the ability of the land market to recover. This may account for the contradictory findings in the published literature.  相似文献   
28.
/ The last 20 years have seen the successful application of environmental dispute resolution processes, where people voluntarily negotiate toward mutually acceptable solutions, to many environmental disputes. The effects of contextual influences, such as the number of parties and presence of deadlines, on outcomes are known and frequently described. Less well documented and understood are the interaction processes themselves. This paper draws on two case studies to develop a conceptual framework describing these processes. Disputes associated with management planning for the Bob Marshall Wilderness Complex in the United States and Fitzgerald River National Park in Australia provided the cases. The conceptual framework derived had eight sequential stages: (1) joint definition of problems, (2) uncertainty about what to do, (3) agreement on group procedures, (4) realization of interdependence, (5) enthusiasm about collective possibilities, (6) commitment to working together, (7) consolidation of the group, and (8) implementation of a resolution. The framework provides new insights for managers of public wildlands, especially the need for varying but ongoing managerial involvement in dispute resolution processes. High levels of involvement and influence are essential at the beginning in problem definition and group procedure design and at the end in implementing resolutions. Conversely, agency members must be willing to exert less influence, while still being involved and committed to collective purposes, during the middle stages. Also apparent from the conceptual framework is the importance of developing shared understandings and of allowing sufficient time for understanding to develop, if successful resolution is to be achieved. KEY WORDS: Environmental dispute resolution; Conceptual framework; Public wildlands; Shared understandings; Australia  相似文献   
29.
An active ethically conscious consumer has been acclaimed as the new hero and hope for an ethically improved capitalism. Through consumers’ “voting” at the checkout, corporations are supposed to be held accountable for their conduct. In the literature on political consumerism, this has mainly been approached as political participation and governance. In this article, we do a critical review of this literature. We do so by questioning the existence of what we call a “generic active consumer model.” At the core of this position, there is a belief that the active consumer is a universal entity, available across nations and time. Instead we call for an approach that takes accord of the ways consumers and consumer roles are framed in interactive processes in markets, governance structures, and everyday life. Consumers in different countries assess their responsibilities and their powers as consumers differently due to different institutionalizations within distinctive contexts. We also must take into account how the inertia of ordinary consumption and the moral complexities of everyday life restrict the adoption of an active consumerist role. Hence, the debate on political consumerism should make for a more realistic notion of ethical consumer-sovereignty and its role in improving the workings of capitalism. In our view, these findings have severe implications for understanding both theories of political consumption and the dynamics of political consumption per se.  相似文献   
30.
Death in fishing gear of non-target species (called ‘bycatch’) is a major concern for marine wildlife, and mostly worrying for long-lived species like cetaceans, considering their demographic characteristics (slow population growth rates and low fecundity). In European waters, cetaceans are highly impacted by this phenomenon. Under the Common Fishery Policy, the EC 812/2004 regulation constitutes a legal frame for bycatch monitoring on 5–10% of fishing vessels >15 m. The aim of this work was to compare parameters and bycatch estimates of common dolphins (Delphinus delphis) provided by observer programmes in France and UK national reports and those inferred from stranding data, through two approaches. Bycatch was estimated from stranding data, first by correcting effectives from drift conditions (using a drift prediction model) and then by estimating the probability of being buoyant. Observer programmes on fishing vessels allowed us to identify the specificity of the interaction between common dolphins and fishing gear, and provided low estimates of annual bycaught animals (around 550 animals year−1). However, observer programmes are hindered by logistical and administrative constraints, and the sampling scheme seems to be poorly designed for the detection of marine mammal bycatches. The analyses of strandings by considering drift conditions highlighted areas with high levels of interactions between common dolphins and fisheries. Since 1997, the highest densities of bycaught dolphins at sea were located in the southern part of the continental shelf and slope of the Bay of Biscay. Bycatch numbers inferred from strandings suggested very high levels, ranging from 3650 dolphins year−1 [2250–7000] to 4700 [3850–5750] dolphins year−1, depending on methodological choices. The main advantage of stranding data is its large spatial scale, cutting across administrative boundaries. Diverging estimates between observer programmes and stranding interpretation can set very different management consequences: observer programmes suggest a sustainable situation for common dolphins, whereas estimates based on strandings highlight a very worrying and unsustainable process.  相似文献   
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