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411.
长江源自然保护区生态环境状况及功能区划分   总被引:1,自引:0,他引:1  
长江源区是长江流域的特殊生态功能区 ,也是我国最重要的生态功能区之一。其生态环境的好坏 ,不仅关系到当地人民的生存与发展 ,而且会影响整个长江流域的可持续发展。简要介绍了长江源区的基本概况 ,分析了源区目前存在冰川退缩、冻土退化、草场退化、土地沙化、湖泊萎缩、生物多样性遭受破坏等主要生态环境问题。造成这种状况的有自然因素 ,也有人为因素 ,自然原因占主导地位 ,而人为因素加剧了生态环境的恶化。赞成在长江源区建立国家级自然保护区 ,提出了建设长江源自然保护区功能区的思想 ,认为保护区应重点保护水源地、生物多样性和特殊生态系统。在野外调查的基础上 ,建议将保护区划分成 5个核心区 ,3个缓冲区和 2个实验区。核心区生物多样性最丰富 ,生态系统的代表性最强 ,水源涵养作用最大 ,生态系统受人类干扰和破坏程度最小。  相似文献   
412.
1 INTRODUCTION Nature reserves are special regional ecological systems. They are the cornerstone for the protection of ecosystems on a global scale (Fuentes et al., 2000), and a necessary method to protect biological resource, species, and the diversity of the ecosystem (Zhang, L.Y., et al., 2002). Since the 1970s the research for designing, planning, and managing various kinds of nature reserves has seen rapid development. Many sorts of disturbance factors occurring in nature reserves, …  相似文献   
413.
This study explores conflict in recreational use of the Black Forest Nature Park (BFNP) by six different nature sports groups as a function of infrastructure, forest management and other users. A multi-step, methodological triangulation conflict model from US recreation management was applied and tested in the Park. Results from two groups, hikers and mountain bikers, are analysed in depth. The main conflict potentials were due to infrastructure and value conflicts. These were influenced by various visitor characteristics such as resource attachment, experiences, activity-style, expectations and motives. Results of quantitative data analysis were further interpreted by interviews with agency and group leaders. This methodological combination reveals a robust understanding of recreation conflict and management in the BFNP.  相似文献   
414.
This paper discusses the misuses of estuaries in Northeast of Brazil and the social contrasts there found. The several kinds of impacts promoted by capitalist enterprises in one side and by traditional population, who uses estuary areas at another side, are in complete disagreement with the ethic of sustainable development. Our intention is to demonstrate how these aspects occur in the River Paraíba do Norte estuary, in the State of Paraíba. Observing the conditions of infrastructure besides the multiple ways to handle along with the extension of the estuary, we could recognize 59 focus of conflict between the incorrect use and sustainable mode. Most of the uses concern to traditional artisan fishing, slums and recreational marinas, reflecting the great social contrast between rich and poor people settled in area studied. Ecological and social implications of these conflicting uses are discussed and measures to improve the situation are suggested.  相似文献   
415.
Abstract:  Biological control with specialist, nonindigenous, herbivorous insects is an important option for controlling invasive exotic plants in wildlands and nature reserves. It is assumed that biological control agents will reduce the dominance of the target weed, thereby increasing the native diversity of the associated plant community. However, this hypothesis has rarely been tested. We introduced Aphthona nigriscutis into grassland sites infested with the invasive exotic species Euphorbia esula L. on a nature reserve in Montana (U.S.A.). Two sites with better soil had been treated previously with herbicide, whereas two other sites had not. We measured the density and biomass of Euphorbia vegetative and flowering stems and number of native and exotic shrubs, grass-like plants, and forbs in 48 microplots in Aphthona release and control macroplots at each site. After 5 years, Aphthona release was associated with a 33–39% decline in Euphorbia aboveground biomass compared with controls at all sites. Other effects of the biocontrol depended on the site. Biocontrol slowed the recovery of species diversity at the sites previously treated with herbicide but slowed the loss of diversity at sites without a history of herbicide. Biocontrol introduction was not associated with a disproportionate increase in nontarget exotic species. Release of Aphthona caused a decline in the biomass of flowering stems relative to controls at good-soil, previous-herbicide sites but was associated with a relative increase in flower stem mass at poor-soil, no-herbicide sites. Our results suggest that biocontrol reductions in weed dominance will not always be associated with increased species diversity. More emphasis should be placed on conserving desirable communities and less on simple weed control. Monitoring of community-level effects should accompany biocontrol introductions on nature reserves.  相似文献   
416.
确立生态价值观:人与自然和谐的关键   总被引:6,自引:0,他引:6  
构建和谐社会包括人与自然、人与人、人与自身的和谐,但人与自然的和谐是构建和谐社会的基础。如何实现人与自然的和谐,必须确立生态何时何地观。全球性的生态危机,向我们提出一个问题:每一代人究竟应当怎样衡量自己创造的文明成就。又应当如何评价自己决策行为的功过得失。要回答这个问题.关键在于价值,在于价值的取向与判断标准。我们反思过去的经济行为。必须确立这样的价值观。就是自然资源是有价值的。这是实现人与自然的和谐的根本保证。  相似文献   
417.
农村水环境内生治理机制是外源治理力量"嵌入"的前提和运行保障,加强农村内在要素的水环境治理参与对于农村生态社区建设具有重要意义.内生治理效用的高低不仅取决于农村社区成员的组织化程度还较多受到环境政策执行效果的影响,细致分析时下农村水环境治理的内部结构,农户参与不足、民间组织承接能力不高、社区公共性消减和政策执行偏差等问题在较大程度上制约着农村内生秩序与农村生态社区建设的和谐共进.进一步厘清农村水环境内生治理的强化进路,可从参与渠道拓展、民间组织培育、内生秩序转型以及治理规范制定四个方面加以调整,不断促进农村水环境治理的内外互动.  相似文献   
418.
环境责任的核心是对环境利益的损害予以救济,环境责任理论构建的出发点和落脚点必须围绕环境利益展开,环境责任的定义、特性以及环境责任形式都应以对环境利益的关怀为着力点。依照此思路,文章主张环境责任的特性在于融合性和可转嫁性,环境责任形式可以概括为恢复原态、排除危害和承担损失。  相似文献   
419.
鸦来公路鹤峰县城关至宣恩县当阳坪段改建工程受走廊带限制经过湖北七姊妹山国家级自然保护区缓冲区和实验区,文章在未修改自然保护区功能区的前提下,对原有公路自然保护区段进行植被恢复缓解自然保护区新建公路的影响,并对上述影响进行比较、分析,得出总体效果呈现正影响,在保护区内实施生态影响"以新带老"建设工程可行,建议在《中华人民共和国自然保护区条例》修编时考虑增加对有利于保护区的工程允许建设的有关规定。  相似文献   
420.
SUMMARY

What is sustainable development? Why is at an issue? Ideally, what needs to be done? and Practically, what can be done? are answered here by relying on the cultural theory of Mary Douglas and her colleagues, more especially Aaron Wildavsky and Michael Thompson, both of whom have used the model to address sustainable development. The implications of cultural theory for sustainable development are substantial.

The article is divided into five sections. The first describes the current controversy over sustainable development. The second sets out the cultural theory model, and the third applies that model to reformulate our understanding of sustainable development. The fourth draws out the implications of a reformulated sustainable development, while the conclusion uses those implications to answer the four questions that started the article.  相似文献   
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