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61.
长江防护林体系工程建设可持续性评价 总被引:1,自引:0,他引:1
在系统总结长江防护林体系工程20年建设目标实施与成效的基础上,针对工程自身和外部条件,对可持续经营、可持续发展及后续建设基本思路与重点进行分析评价。 相似文献
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An integrated hydro-economic modelling framework to evaluate water allocation strategies II: Scenario assessment 总被引:2,自引:0,他引:2
Biju George Hector MalanoBrian Davidson Petra HellegersLuna Bharati Sylvain Massuel 《Agricultural Water Management》2011,98(5):747-758
In this paper the results of an assessment of the hydrological and economic implications of reallocating water in the Musi sub-basin, a catchment within the Krishna Basin in India, are reported. Policy makers identified a number of different but plausible scenarios that could apply in the sub-basin, involving; supplying additional urban demand from agricultural allocations of water, implementing a number of demand management strategies, changing the timing of releases for hydropower generation, changing the crops grown under irrigation, reducing existing stream flows and allowing for more environmental flows. The framework chosen to undertake this assessment was a simulation model that measures and compares the economic values of water allocation scenarios determined from a water allocation model that accounts for supplies of groundwater and surface water across a number of regions and over a variety of uses. Policy makers are provided with the range of measures on the security of the supply of water and the social costs and benefits of reallocating water between sectors and across regions within the sub-basin. Taking water from agriculture to supply urban users has a greater impact on irrigation supplies during dry years. It was also found that changing the allocation of water between sectors, by taking it away from agriculture had a large positive economic impact on the urban sector. Yet the costs involved in undertaking such a strategy results in a significant loss in the net present value of the scheme. Stream flow reductions, if significantly large (at around 20%), were found to have a large physical and economic impact on the agricultural sector. Implementing water saving strategies in Hyderabad was found to be more cost effective than taking water from agriculture, if rainwater tanks are used to achieve this. Changing the timing of hydropower flows resulted in best meeting of irrigation demand in NSLC and NSRC. Under this scenario, the crops grown under irrigation were found to have a significant economic impact on the sub-basin, but not as large as farmers undertaking crop diversification strategies, ones which result in farmers growing less rice. The security of supplying water to different agricultural zones has significantly improved under this scenario. Finally, releasing water for environmental purposes was found to have only a minor impact on the agricultural sector. 相似文献
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介绍了南水北调中线工程、受水区经济发展现状及水资源短缺对经济发展的影响等问题。提出在实施南水北调中线工程的同时应树立节水观念,建设节水型社会,发展节水型产业,加大治理污染力度,解决好水库移民安置问题,进行受水区域的生态修复规划,建立新的水资源管理体制以及合理的水价形成机制等建议。 相似文献
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何玮 《农业环境科学学报》2007,(5)
结合多年医药科技查新的实践经验和体会,针对查新项目委托书填写过程中出现的问题、后果和相应对策进行了总结和探讨,强调应重视查新项目委托书的填写,并针对医药科技立项课题对如何做好查新工作进行了阐述。 相似文献
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介绍了永善县天然保护及退耕还林工程的实施目标。总结了该2项工程实施以来在公益林建设、森林管护、人员分流安置、基础设施建设、退耕地造林、荒山造林、补植补造、幼林抚育、粮食兑现、现金兑现等方面取得的成果。分析了在工程实施中存在的问题和困难。提出了今后的措施和建议。 相似文献
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宜黄县在退耕还林工程建设中,形成了一套行之有效的方法和措施,仅一年时间,就完成坡耕地退耕2047hm^2,荒山造林1667hm^2。 相似文献
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