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941.
景观生态学在公路建设项目环境影响评价中的应用   总被引:5,自引:0,他引:5  
景观生态学中的优势度原理在评价开发建设项目对生态系统完整性及其结构与功能稳定性方面具有很好的适用性,但在线型开发建设项目环境影响评价中很少应用。以公路建设为例,探讨了在线型开发建设项目生态环境影响评价中的应用。  相似文献   
942.
塔里木河下游绿色走廊的生态问题与治理对策   总被引:2,自引:0,他引:2  
从经济、军事和生态三个角度分析了保护塔里木河下游绿色走廊的必要性,概括了该区域的生态环境现状,即河水矿化度升高、地下水位下降从而导致植被的退化和沙漠化加剧的问题。最后提出了以水资源合理利用为前提和中心的治理对策。  相似文献   
943.
胡杨林的衰退原因与林地恢复策略   总被引:8,自引:0,他引:8  
黄培祐 《新疆环境保护》2004,26(Z1):121-124
胡杨广布于地中海沿岸并呈带状东延至中国和蒙古人民共和国。目前,胡杨林已普遍呈不同程度退化,以塔里木盆地为例,垦伐等人为因素使林地总面积迅速减少。现场观测发现,一些林区缺乏胸径20cm以下的立木,而该地从1972年以来断绝洪水来源,显示洪水对幼苗补给可能存在相关,该地断绝洪水多年后,2002年重新出现洪泛过程,洪水退后出现大量的幼苗生长,从而证实洪水过程是胡杨幼林发生的必要条件。本文就此现象提出恢复部分林地的对策。  相似文献   
944.
大气环境法是随大气环境的变化而发展的。通过分析美、日、中等国家近年来的大气环境立法状况,概括出目前大气环境立法的五大趋势。这些趋势反映了人们对大气污染防治问题认识的深入和对大气环境污染防治法律观念的转变。  相似文献   
945.
在分析了送风机主要噪声源及频谱、噪声特性的基础上,应用噪声控制理论,设计并实施了噪声控制方案,达到了预期的治理效果。  相似文献   
946.
Developments in biotechnology and genomics have moved the issue of patenting scientific and technological inventions toward the center of interest. In particular, the patentability of genes of plants, animals, or humans and of genetically modified (parts of) living organisms has been discussed, and questioned, from various normative perspectives. This paper aims to contribute to this debate. For this purpose, it first explains a number of relevant aspects of the theory and practice of patenting. The focus is on a special and increasingly significant type of patents, namely product patents. The paper provides three general arguments against the concept and practice of product patenting. The first argument briefly considers the claim that patents are legitimate because they promote socially useful innovation. Against this claim, it is argued that product patents may hamper rather than promote such innovation. The second and main argument concludes that product patents are not adequately based on actual technological inventions, as they should be according to the usual criteria of patentability. The principal moral issue is that product patents tend to reward patentees for inventions they have not really made available. The final argument proposes a method for patenting the heat of the sun. Assuming that granting this patent will be generally considered absurd, the argument exposes a further, fundamental problem of the concept and practice of product patenting.  相似文献   
947.
This article develops a practical proposal for progress on sustainable development law. It examines the prospects for an international sustainable development law to provide a framework for more effective, coherent governance. Sustainable development law is briefly defined and an analytical framework is provided. Different degrees of integration between economic, social and environmental law are described. Certain principles of international law related to sustainable development are also highlighted. It is argued that these principles may serve to guide law‐makers and jurists where social, economic and environmental law and policy conflict or overlap. Continuing, underlying questions of sustainable development governance are addressed and its global frameworks analysed. The article also focuses on the 2002 World Summit on Sustainable Development, held in Johannesburg in August‐September 2002, and its specific mandate for the United Nations Commission on Sustainable Development (UNCSD) to take related legal developments into account. The article advances a proposal: that governments, economic, social and environmental intergovernmental organizations and other actors establish a ‘network of inquiry’ with members from relevant groups, including legal and academic organizations, and other expert groups, in order to follow, research, analyse and debate legal developments in a balanced way.  相似文献   
948.
ABSTRACT: Erosion from construction sites significantly affects water quality in receiving streams. A rainfall simulator was used to evaluate the effectiveness of different methods for controlling erosion from construction sites. Erosion control methods investigated included dry and liquid applications of polyacrylamide (PAM), hydroseed, and straw mulch. Fertilizer was also applied to each plot to examine the effectiveness of the methods in reducing nutrient losses in runoff. Runoff samples were analyzed for total suspended solids (TSS), nitrate, total Kjeldahl nitrogen (TKN), ammonium, total phosphorus (TP), and orthophosphate. Among all treatments investigated, straw mulch was the most effective treatment for controlling TSS and nutrient losses during short term and long term simulations. The low liquid PAM (half the recommended PAM) treatment resulted in the highest reduction in runoff, TSS bound nitrogen, and total nitrogen (TN) concentrations and loadings. The study results indicate that a high application rate (twice the recommended rate) of PAM could actually increase runoff and TSS losses. At a low application rate, both liquid and dry PAM were effective in reducing TSS and nutrient losses in runoff. However, application of the liquid form of PAM to construction sites is more practical and perhaps more economical than applying the PAM in the dry form.  相似文献   
949.
杨鹏程 《灾害学》2004,19(3):72-75
除水旱灾害之外,清代后期对湖南危害较大的灾种主要为虫灾,风灾、雹灾、冰冻雪灾偶有发生.本文对上述灾害的灾情进行了论述.  相似文献   
950.
任隽  袁志祥  冯希杰  范增节 《灾害学》2004,19(Z1):53-56
2003年4月24日陕西省石泉县红卫乡一带发生ML4.9级地震.这次地震对石泉、汉阴等县建筑物特别是农村建筑物造成一定程度的破坏,本文统计了不同类型的房屋建筑破坏情况,并对此进行了分析和探讨.  相似文献   
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