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891.
建立三峡库区生态经济区的战略思考 总被引:11,自引:0,他引:11
三峡库区面临着生态环境恶化、经济贫困化、百分移民安置等三大难题。要使这三大难题从根本上得以有效协调解决,必须发展生态经济。本文提出了从生态农业、生态工业、生态城镇、生态旅游业等方面构建三峡库区生态经济区的思想。 相似文献
892.
893.
大伙房水库输水工程水生生物水质生态评价 总被引:3,自引:0,他引:3
对大伙房水库输水工程沿线地表水体中的藻类、浮游动物、底栖动物 (水生昆虫 )进行了监测 ,从生物学的角度对其水质进行了评价 ,并对引水后水生生物多样性的变化进行分析 相似文献
894.
895.
岩溶地区作为一个特殊的地理环境单元,具有环境承载量低、地表崎岖破碎、植被生长困难、生态环境脆弱的特点。该文以岩溶地貌发育典型、碳酸盐岩出露面积广的贵州省为例,论述了岩溶区生态环境脆弱性类型划分的主要原则,探讨了脆弱性类型划分的指标并进行了量化。在此基础上,用灰色关联度分析确定了各影响因子(指标)的权重,经过综合评判,笔者把贵州岩溶区生态环境脆弱性类型划分为5类:剧烈脆弱区、强度脆弱区、中度脆弱区、轻度脆弱区和潜在脆弱区,并针对各脆弱性类型区的特点,提出了相应的防治对策。 相似文献
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897.
China’s new Classification-Based Forest Management (CFM) is a two-class system, including Commodity Forest (CoF) and Ecological
Welfare Forest (EWF) lands, so named according to differences in their distinct functions and services. The purposes of CFM
are to improve forestry economic systems, strengthen resource management in a market economy, ease the conflicts between wood
demands and public welfare, and meet the diversified needs for forest services in China. The formative process of China’s
CFM has involved a series of trials and revisions. China’s central government accelerated the reform of CFM in the year 2000
and completed the final version in 2003. CFM was implemented at the provincial level with the aid of subsidies from the central
government. About a quarter of the forestland in China was approved as National EWF lands by the State Forestry Administration
in 2006 and 2007. Logging is prohibited on National EWF lands, and their landowners or managers receive subsidies of about
70 RMB (US$10) per hectare from the central government. CFM represents a new forestry strategy in China and its implementation
inevitably faces challenges in promoting the understanding of forest ecological services, generalizing nationwide criteria
for identifying EWF and CoF lands, setting up forest-specific compensation mechanisms for ecological benefits, enhancing the
knowledge of administrators and the general public about CFM, and sustaining EWF lands under China’s current forestland tenure
system. CFM does, however, offer a viable pathway toward sustainable forest management in China. 相似文献
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899.
900.
Polluting substances are spread as a consequence of the construction and use of roads. This article provides a summary of
the substances with which traffic pollutes the environment on a local, regional and global level. The mechanisms of dispersion
of pollutants to soil and groundwater are described. Based on environmental quality requirements established in rules and
regulations in the Netherlands, the paper discusses mitigating measures necessary to limit the distribution of pollutants
along highways. Most of the data in this article come from original research carried out by or by order of the Road and Hydraulic
Institute. For comparison, other data from the Netherlands have been included. It is shown that source-oriented measures (volume
and technical) will have more effect on environmental quality than measures with regard to treating runoff. The use of porous
asphalt instead of nonporous asphalt on highways in the Netherlands has environmental benefits. The article also pays attention
to combined use of the roadside verges for treatment of runoff using ecological engineering techniques in the form of natural
processes in helophyte filter systems in combination with enhancement of ecological values along highways. 相似文献