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281.
流域水生态系统健康与生态文明建设   总被引:2,自引:0,他引:2       下载免费PDF全文
孟伟  范俊韬  张远 《环境科学研究》2015,28(10):1495-1500
健康的流域水生态系统是保障流域经济社会可持续发展的基础,解决我国严峻的流域水生态系统健康问题迫切需要开展以流域为基本单元的生态文明建设. 针对我国流域水生态系统健康现状,确立了流域生态文明的概念和内涵,提出了流域生态文明建设的基本框架和主要任务. 以保障流域自然生态系统的完整性、流域经济社会系统发展的可持续性、人居环境的生态性为内涵,构建流域水生态-经济社会复合生态系统的动态平衡是流域生态文明建设的基本框架. 流域生态文明建设的主要任务:①构建以水生态系统健康为目标的流域分区管理模式,优化国土空间开发;②健全流域的水环境质量基准和标准体系,科学确定生态系统保护阈值;③建立以流域生态承载力为约束的污染物总量控制技术,优化产业结构与布局;④以保障流域环境流量为前提,实现水资源生态利用;⑤加强人居环境生态建设,实现流域城市生态化发展;⑥加强生态制度建设,构建流域生态文明建设长效机制.该研究成果可以为实现流域人与自然和谐发展提供理论指导.   相似文献   
282.
"十四五"期间,粤港澳大湾区将会迎来新一轮大开发、大建设、大发展,绿色发展与山水林田湖草一体化保护将面临更大的机遇与挑战。生态环境监测作为生态环境保护的重要基础,亟需强化支撑、引领、服务作用。文章对粤港澳大湾区生态环境监测发展现状进行了梳理,从环境质量状况、生态环境管理、环境监测网络等方面将粤港澳大湾区与东京、纽约、旧金山三大世界级湾区进行系统比较,对标查找差距与不足,并对面临的机遇与挑战进行了深入剖析。在此基础上,针对生态环境监测区域布局、现代感知网络、智慧应用与"美丽湾区"综合评价、联合监测与信息发布、产学研用一体化等方面,提出了粤港澳大湾区当前及今后一个时期生态环境监测发展的相关建议。  相似文献   
283.
西南国际河流水资源状态及开发中的问题   总被引:2,自引:0,他引:2  
西南国际河流流域地形复杂、海拔高、人口稀少,人均水资源量丰富,出境水量大,水质好,目前开发利用程度低,具有广阔的开发利用前景。但随着我国加入WTO,经济和社会发展融入国际的步伐加快,对国际河流的开发和利用也必然要按照国际法或国际惯例。首先对西南国际河流水资源的自然状态,我国在各自流域中的地位、开发利用状态以及存在的问题进行了论述;然后讨论国际河流开发中应注意的问题和准则;最后,根据可持续发展的原则和各个河流的特点,提出建议:应该充分认识到我国西南国际河流地区生态环境脆弱和社会经济发展水平较低的状态,今后应以水资源保护为主,优先发展航运和旅游业,合理开发水能资源。同时应积极参与国际合作与交流,与相关国家共同开发流域水资源,促进流域经济社会的可持续发展。  相似文献   
284.
Atatürk Dam Lake is one of the important freshwater ecosystems in the world in terms of the size of the surface area and the biodiversity. The objective of this study was to determine the effects of metal pollution in the Atatürk Dam Lake on some biochemical markers in the gills and digestive glands of mussels (Unio mancus). Mussel samples were collected in July-2018 from four stations. The metal residues (Cd, Cu, Pb, Zn, and Ni) in the tissues were determined by ICP-MS. The MT, reduced GSH, and MDA levels were analysed using the proposed spectrophotometric methods. According to the results, toxic metals such as Cd and Pb in both tissues were determined mostly in mussels collected from St1. The highest MT and MDA levels in the gills were determined in St3 and St2 respectively, while the highest MT and MDA levels in the digestive glands were determined in St1. Although there was no significant difference in the reduced GSH level in the gills among the stations, the highest reduced GSH level in the digestive glands was determined in St4. These results indicated that mussels are appropriate sentinel organisms for metal contamination with effects on oxidative stress and metal exposure biomarkers.  相似文献   
285.
Le SA  Majid N 《Disasters》2002,26(1):10-27
A 'livelihoods gap' has become evident in international aid delivery to Somalia. Existing aid interventions do not address the economic dynamics of vulnerability resulting from Somalia's long history of predatory development and asset stripping. To prevent poor households' regular return to sub-subsistence income levels after a brief period of plenty, this paper argues that aid agencies should reorient and expand existing interventions to assist poor households to capitalise on temporary improvements in environmental and security conditions. As a corollary to emergency relief and efforts to construct state institutions, it is necessary to devise country-wide interventions that will rebuild household asset bases by protecting savings during times of stress and ensuring that markets benefit poor producers.  相似文献   
286.
Environmental Education: Biodiversity   总被引:4,自引:0,他引:4  
Environmental education was a principal topic on the agenda of the Stockholm 1972 Conference. In response to its recommendation UNESCO and UNEP developed and launched the International Environmental Education Program (IEEP) in 1977. Environmental education was perceived to encompass in-school and out-of-school activities and public awareness. Later developments added training to its objectives and the concept of sustainable development to its dimensions. The international Convention on Biological Diversity (CBD) represented a phase in the world commitment to conservation of nature. It underpinned biodiversity in the fields of environmental education. Biodiversity education is based on five pivots: scale of boundaries (from local to worldwide), perspectives, goals, themes (vary according to actors), and assimilation (evaluation of programs of action). Directions relate to learners and teachers, and processes address: awareness, school education, education (and professional training) at tertiary level, roles of communication and media institutions.  相似文献   
287.
“A skyscraper is as natural as a bird’s nest” –Alan Watts For millennia, people have altered freshwater ecosystems directly through water development and indirectly by global change and surrounding land-use activities. In these altered ecosystems, human impacts can be subtle and are sometimes overlooked by the people who manage them. This article provides two case studies near Boulder, Colorado that demonstrate how perceptions regarding these ecosystems affect their management. These examples are typical of lakes and streams along the Front Range of Colorado that are simultaneously natural and social in origin. Although natural, many of the region’s freshwater ecosystems are affected by ongoing ecologic, hydrologic, chemical, and geomorphic modifications produced by human activity. People and nature are both active participants in the production of these freshwater ecosystems. The concept of “hybridity,” borrowed from geographers and social scientists, is useful for describing landscapes of natural and social origin. Hybrid freshwater ecosystems are features of the humanized landscape and are derived from deliberate cultural activities, nonhuman physical and biological processes, and incidental anthropogenic disturbance. Our perceptions of “natural” freshwater ecosystems and what definitions we use to describe them influences our view of hybrid systems and, in turn, affects management decisions regarding them. This work stresses the importance of understanding the underlying societal forces and cultural values responsible for the creation of hybrid freshwater ecosystems as a central step in their conservation and management.  相似文献   
288.
Philip White 《Disasters》2005,29(S1):S92-S113
This paper examines the 1998–2000 'border' war between Eritrea and Ethiopia and its continuing legacies from the perspective of food security.1 Focusing on the food crisis that hit both countries during the same period and was allowed to develop into a famine in southeast Ethiopia, it argues that this was linked with the war in more ways than hitherto recognised. Such connections can be appreciated only by taking a longer-term view of the decline of the rural economy of which this food crisis was part, factoring in the role played by this and other conflicts that have flared up in the region. An analysis of this kind might have helped donors and aid agencies to respond more effectively both to short-term humanitarian needs in the midst of an inter-state war and to the need for longer-term support for food security in a region beset by endemic conflict.  相似文献   
289.
This paper describes a heuristic model which helps to relate a developing nation's environmental risk to the level of sophistication appropriate in adjusting management strategy to dealing with environmental hazards. The model takes into account three factors: the degree of risk, the stage of economic growth, and the sophistication of adjustment. The interrelationship of these factors is examined, and the role of international cooperation in establishing strategies is outlined.  相似文献   
290.
This article examines develop-for-import projects financed by development loans and mixed credits supplied by export-import banks and other financial institutions of the central governments of France, Japan and the Federal Republic of Germany. The projects discussed are those producing bauxite, alumina, aluminium, chromium, copper, iron, manganese, molybdenum, nickel and tungsten, in developing market economies, Australia and Canada. The article estimates the volume of these metals committed to France, Japan and FRG to pay for loans and credits, examines the types of financial arrangement involved in develop-for-import projects, and considers the compatibility of these arrangements with the multilateral liberalized world trading system developed by the General Ageement on Tariffs and Trade (GATT) over the past 40 years. To the extent that these arrangements do not fully reflect changes in international market forces, world trade in metals will tend to be distorted and discriminatory.  相似文献   
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