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991.
通过在湖南省祁东县紫云材进行的土地利用及农户经济行为调查,从土地状况、从业选择、农具、农田设施、耕作方式和效益等方面,分析了湘南红壤丘陵区农户社会经济行为对土地质量的影响。结果表明:紫云村农户重“品种”轻“土壤”,水田土壤有机质含量减少,理化性状变差,土壤自然肥力降低,旱地、林地粗放经营,质量退化。改变农户只重“品种”而忽视“土壤”的观念、提高耕地复种指数、建立合理的轮作体系和水土保持型高效集约持续的耕作制度、加强林业管理和经营、加大农业投入、搞好农田水利建设是防止本区土地退化和保证本区农业可持续发展的对策。  相似文献   
992.
西藏地处我国西部 ,西藏开发是西部大开发的重要组成部分。通过对长江经济带和西藏开发的关系及西藏发展的历史、现状和问题的分析 ,认为长江经济带有能力 ,也有必要支持西藏自治区的发展。根据西藏目前的发展现状和存在的问题来看 ,长江经济带有必要在新的背景条件下 ,寻求更好的战略模式促进西藏开发。也即同西藏两地通过文化交流促进经济融合 ,以改变观念为出发点 ,拓展潜在市场为目标 ,达到促进西藏开发和长江经济带进一步发展的双重目的。长江战略的实施要点包括 :(1)推广双语学习 ,以文化交流促进经济融合 ;(2 )提高藏语教学的师资质量 ,改善劳动力整体素质 ;(3)让一部分藏民先富起来 ,成为西藏开发的中坚力量 ;(4)合作协助发展交通、通讯等基础设施 ,完善交流手段 ;(5 )帮助扶植西藏地区的起步产业 ,逐步培养自立发展经济的能力  相似文献   
993.
The link between environmental and economic performance has been widely debated in the literature for the last ten to fifteen years. One view is that improved environmental performance mainly causes extra costs for the firm and thus reduces profitability. However, also the opposite has been argued for: improved environmental performance would induce cost savings and increase sales and thus improve economic performance. Theoretical and empirical research have provided arguments for both positions and have not been conclusive so far. This article discusses reasons for the different views and the differences in empirical research and presents a theoretical framework to explain the coexistence of the conflicting views. It is argued that not merely the level of environmental performance, but mainly the kind of environmental management with which a certain level is achieved, influences the economic outcome. The model presented provides implications for both empirical research and company management in practice. Research and business practice should focus less on general correlations and more on causal relationships of eco-efficiency, i.e. the effect of different environmental management approaches on economic performance.  相似文献   
994.
石油短缺与中国经济安全   总被引:6,自引:0,他引:6  
石油短缺已经成为引起中国能源危机最核心的问题,本文分析了中国石油短缺的背景及其影响因素,在实证分析的基础上,提出了“对石油依赖程度”这一概念。本文还把石油短缺与经济安全问题联系了起来,并提出了确保我国经济安全的具体对策。  相似文献   
995.
Multiple negotiating rounds of the General Agreement on Tariffs and Trade (GATT) and World Trade Organization (WTO) since 1947 have conferred economic benefits through liberalized international trade. A growing body of evidence also points to linkages between liberalized trade and damage to the global environment, ecology, and natural resource base. Ironically, the increased economic well-being conferred by trade liberalization ultimately provides the basis for improved environmental protection. It is the interim environmental damage due to trade liberalization that is controversial and needing amelioration. The proposition here is to promote further trade liberalization, but only as long as environmental ethics and sustainability issues are satisfactorily addressed. Trade liberalization should not be permitted at the expense of adequate environmental protection and sustainability. Future WTO rounds need to address both development benefits and environmental ethics issues in a net social welfare maximization setting.  相似文献   
996.
A plant-based bioremediation (phytoremediation) strategy has been developed and shown to be effective for the clean-up of soil contaminated by the breakdown products of the chemical warfare agent (CWA), yperite. The method involves exploiting the plant growth hormone, indole-3-acetic acid (IAA), to intensify the phytoremediation. For determination of the yperite breakdown products, gas chromatography is used. Soil and plant samples were analysed with a gas chromatograph fitted with an atomic emission detector. The method of standard-free determination was employed to identify sulphur-containing substances (SCSs). A series of soil tests was conducted, which showed that the level of SCSs decreased 4, 8, and more than 20-fold compared with that found in contaminated soil. This decrease was dependent upon the IAA concentrations used for plant treatment. The treated plants accumulated 2.7 to 2.9-fold larger amounts of the SCSs than did the untreated plants. Owing to its simplicity, environmental safety and inexpensiveness, the method can be recommended for the restoration of soil fertility in areas of storage and destruction of blister CWAs.  相似文献   
997.
在100mL混合酒精培养液中接种优质复合菌种8503和8505,在接种量为体积浓度10%,温度为30.0℃,转速为170r/min的条件下,经摇床培养48h后,绝于菌体质量最高可收获1.4693g,COD去除率高达67.74%,即COD由发酵前的32680mg/L,降为发酵后的10544mg/L。  相似文献   
998.
湛江具有较强的港口、地缘和腹地优势。要充分利用这些优势,开辟海洋型经济产业开发带,开发利用好海洋资源,促进湛江经济的腾飞。  相似文献   
999.
Multiple negotiating rounds of the GeneralAgreement on Tariffs and Trade (GATT) and World TradeOrganization (WTO) since 1947 have conferred economicbenefits through liberalized international trade. Agrowing body of evidence also points to linkagesbetween liberalized trade and damage to the globalenvironment, ecology, and natural resource base.Ironically, the increased economic well-beingconferred by trade liberalization ultimately providesthe basis for improved environmental protection. It isthe interim environmental damage due to tradeliberalization that is controversial and needingamelioration. The proposition here is to promotefurther trade liberalization, but only as long asenvironmental ethics and sustainability issues aresatisfactorily addressed. Trade liberalization shouldnot be permitted at the expense of adequateenvironmental protection and sustainability. FutureWTO rounds need to address both development benefitsand environmental ethics issues in a net socialwelfare maximization setting.  相似文献   
1000.
环境污染经济损失估算模型的构建及其应用   总被引:10,自引:0,他引:10  
基于污染物的环境污染损失机理性模型,Logistic方程及环境价值的相关理论,建立了环境污染经济损失估算模型.该模型不仅能反映出污染物浓度、污染物排放量、环境资源价值与经济价值损失间的关系,而且利用该模型可以定量地反映环境污染对环境资源价值造成的损害.将该模型用于估算福州市工业水污染造成的经济损失,其估算量与利用经济计量法计算出的结果进行比较发现:二者评价结果较为一致,但前者略大.   相似文献   
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