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11.
为探析农业规模化经营与农业环境可持续性之间的关系,对农业经营规模对农业环境效率的影响进行理论分析,并在此基础上构建了物料平衡原则下农业环境效率测算模型和农业环境效率影响模型.基于2004~2016年浙江省农户水稻种植地块层面的面板数据,实证检验了土地面积、劳动投入、资本投入和农业产出等农业经营规模指标对农业环境效率的影响.结果显示,农业规模化发展将因投入和产出的扩张以多种方式影响其环境效率,其中土地面积规模与农业环境效率之间呈倒U型关系,劳动投入和资本投入对农业生产环境效率均有负向的影响,而农业产出规模的增加将促进农业环境效率的提升. 相似文献
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Land degradation is a consequence stemming from both natural processes and social economic activities. On the bases of analyzing general situation of agricultural land degradation in China, the monetary estimating methods such as market value method and shadow engineering method were used to quantitatively assess the economic loss resulting from land deterioration. Results showed that the economic loss in 1999 was 326.8l billion RMB Yuan, which accounted for 4.1% of GDP in the same year of China. If taking five items namely farmland conversion, soil erosion, salinization, decline in reservoir functions, and siltation in waterways and, comparing with that in 1992, the percentage of economic loss to GDP has increased by 1.5 in the only 7 years. 相似文献
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浅议农业源和生活源对长桥海的影响 总被引:2,自引:0,他引:2
通过对蒙自下游长桥海水质状况和主要污染源农业源、生活源的分析,提出污染控制对策。 相似文献
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生态系统服务的核算方法 总被引:3,自引:0,他引:3
生态系统服务是指对人类生存及生活质量有贡献的生态系统产品和生态系统功能 ,包括由自然生态过程产生并维持的环境和资源条件。目前已有的生态系统服务核算方法可以分为市场价值法、替代市场法和假想市场法。 相似文献
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Effects of atmospheric mercury pollution on terrestrial ecosystem in Chongqing, China 总被引:1,自引:0,他引:1
1 IntroductionMercury(Hg)asaglobalpollutanthascausedconcernworldwidesincetheendof 1980s.Itisemittedtotheatmospherefrombothanthropogenicandnaturalsources.Importantsourceoftheformeristhedischargefrom productionanduseofHgaswellasthecombustionoffossilfuels(Nri… 相似文献
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This paper explores the practical application of life cycle assessment (LCA) to product system development. While life cycle assessment methods have been studied and demonstrated extensively over the last two decades, their application to product design and development has not been critically addressed. Many organizational and operational factors limit the integration of the three LCA components (inventory analysis, impact assessment and improvement assessment) with product development. Design of the product system can be considered a synthesis of individual decisions and choices made by the design team, which ultimately shape the system's environmental profile. The environmental goal of life cycle design is to minimize the aggregate environmental impacts associated with the product system. Appropriate environmental information must be supplied to decision makers throughout each stage of the development process to achieve this goal. LCA can serve as a source of this information, but informational requirements can vary as the design moves from its conceptual phase, where many design choices are possible, to its detailed design and implementation. Streamlined approaches and other tools, such as design checklists, are essential. The practical use of this tool in product development also depends on the nature and complexity of the product system (e.g. new vs. established), the product development cycle (time-to-market constraints), availability of technical and financial resources, and the design approach (integrated vs. serial). These factors will influence the role and scope of LCA in product development. Effective communication and evaluation of environmental information and the integration of this information with cost, performance, cultural and legal criteria will also be critical to the success of design initiatives based on the life cycle framework. An overview of several of these design initiatives will be presented. 相似文献
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