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Grassland Degradation,Construction and the Econmic-technological Strategies of Sustainable Development of Grassland-agriculture
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作者 WANGHua YUHua-ying +1 位作者 OKAMOTOChinobu WANGYu-sheng 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第1期52-56,共5页
Natural grassland in the West of Northeastern China is located in 40°0′- 43°5′N latitude and 117°0′ -127°5′Elongitude. It lies in the Liao River Valley, the Songhua River Valley and Nen River V... Natural grassland in the West of Northeastern China is located in 40°0′- 43°5′N latitude and 117°0′ -127°5′Elongitude. It lies in the Liao River Valley, the Songhua River Valley and Nen River Valley. About 130 years ago, this region had rich natural grassland resources, was numerically 26.67 millions in hectare of grasslands. Since the last stage of Qing Dynasty, the grassland has been destroyed seriously in 3 times. Up to now, this region only preserved about 2 millions in hectare of the grasslands. In addition, 3.33 millions in hectare of the grasslands have changed from primary grassland to desertification, salinizatio-nalkalinization and degeneration grasslands in the form of patches of bare soil(their simple form of a name is'3 kinds of degeneration grasslands'). This paper indicaed that in any period both grasslands destruction and its restoration were relevant to economic changes and economic systems, particularly to market econmy in that time. The following agricultural economic-technological strategies have been applied to transform of retrogressive grasslands: ① to return reclaimed grassland as farmland to primary grassland in order to greatly increase-economic ecological benefits; ② to close desertification, salinizationalkalinization and degradation grasslands in the form of patches of bare soil; ③to develop grassland-agriculture for establishment of stable production bases of concentrated feed crops and coarse herbage crops. 展开更多
关键词 economic-technological strategy economic benefit grassland destruction vegetation restoration
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对我国突发公共事件的经济学思考 被引量:4
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作者 陈思明 毛惠彬 王芹 《同济大学学报(社会科学版)》 CSSCI 2008年第5期107-113,共7页
本文从经济学角度对我国突发公共事件的原因和对策进行研究,认为对经济利益的破坏性榨取是诱发突发公共事件的主要人为因素;外部性是突发公共事件长期难以抑制的客观基础;而资本边际效率畸高的负外部性投资加剧了制度约束失灵和突发公... 本文从经济学角度对我国突发公共事件的原因和对策进行研究,认为对经济利益的破坏性榨取是诱发突发公共事件的主要人为因素;外部性是突发公共事件长期难以抑制的客观基础;而资本边际效率畸高的负外部性投资加剧了制度约束失灵和突发公共事件的频频发生。文章分析了政府在预防和处置突发公共事件中的核心地位及当前应采取的措施,强调发挥公共产品对预防处置突发公共事件的作用,最后应用法律经济学原理探讨突发公共事件的法定预防标准及预防成本的最小化问题。 展开更多
关键词 突发公共事件 对经济利益的破坏性榨取 负外部性投资 公共产品
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棉蚜最优生物防治指标决策模型
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作者 白志明 张玉峰 马瑞燕 《山西农业大学学报》 CAS 1994年第3期242-245,共4页
本文利用物元分析法建立了瓢虫和棉蚜的生态系统,找出了两个不相容因素(经济效益和生态效益)的相容区间,并在此区间上建立了总效益功能函数。在两因素地位平等的条件下,求出了使总效益功能值最大的最优瓢蚜结构(即棉蚜最优生物防... 本文利用物元分析法建立了瓢虫和棉蚜的生态系统,找出了两个不相容因素(经济效益和生态效益)的相容区间,并在此区间上建立了总效益功能函数。在两因素地位平等的条件下,求出了使总效益功能值最大的最优瓢蚜结构(即棉蚜最优生物防治指标)。对两因素侧重度不同的情形进行了一般性讨论。结果较理想,并具有一定的理论和实用价值。 展开更多
关键词 生物防治指标 生态效益 经济效益 棉蚜
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