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This study aims to implement the empirical analysis of the effects of the adaptive measures on the income of herdsmen in the context of the climate change with the positive mathematical programming(PMP)model.The survey was first implemented in three counties in the Three Headwaters Region.Finally the measures and recommendations suitable for the economic development in the ecologically fragile areas were proposed.The main conclusions are as follows:priority can be given to the measures to prevent the damage from rats and the engineering measures for pasture maintenance in Zeku County,where the geological conditions and grass quality are inferior,while the fiscal subsidy can be prioritized in Tongde County where the grassland area is relatively less.These recommendations can not only provide good reference for the protection of grassland resources,but they also lay a foundation for the implementation of more suitable measures to help the herdsmen in the ecologically fragile areas to adapt to the climate change. 相似文献
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ABSTRACTAs the space carrier of the construction of ecological civilization, land’s green and efficient utilization is an important guarantee for realizing national sustainable development. Based on traditional land evaluation, this paper scientifically defines the green land use, puts land as one of the production factors, and brings energy consumption, environmental pollution, etc. into the input-output system to measure the green land utilization efficiency of the urban construction land of Beijing-Tianjin-Hebei Urban Agglomeration from 2006 to 2016. The study shows that the overall efficiency variation of the urban agglomeration is related with the land and environment policies. Efficiency of 2016 is higher than that of 2006, and energy and environment are the principal factors affecting the green land use. The efficiency of each city is positively correlated with its economic development, negatively correlated with the construction land expansion. Efficiency gaps in different cities are expanding. There is positive correlation with overall weak space between cities, and the partial spatial agglomeration phenomenon appears. Therefore, the green land use efficiency could be improved by improving land utilization efficiency, coordinating economic growth of construction land utilization with environmental protection and taking feasible ways to transregional renovation of the stock ecological land utilization, etc. 相似文献
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In 1999 China adopted the "Conversion of Cropland to Forest and Grassland Program" (CCFGP), a nationwide ecological recovery program, to minimize wide-scale soil erosion and vegetation degradation in China, as well as to improve water budgeting results. In the 10 yr since implementation, the CCFGP has resulted in the recovery and reforestation of >100,000 km of cropland and bare land, though the quantitative effect of this program on catchment water budget is not entirely clear. Therefore, we used the Soil and Water Assessment Tool to evaluate and quantify the effects of the CCFGP on the water budget of the Jinghe River catchment, a tributary of the Yellow River covering the central region of the Loess Plateau. Our results indicated that precipitation had dropped by 12.0% from the 1970s (611.6 mm) to the 2000s (538 mm) and that there was a corresponding 25.2% decrease in humidity index from 0.48 to 0.36. Before the CCFGP's implementation, forest and grassland had been decreasing, while bare land, cropland, and shrub land had been increasing. After the implementation of the CCFGP, the opposite trend was observed. Moreover, streamflow increased by about 15 and 20% for the upstream and middle stream subbasins, respectively, while soil water content also showed an obvious increase. Over the same period, evapotranspiration decreased by 5.2 and 13.5 mm and runoff decreased by 37.5 and 38.6% in the two subbasins. The same trends were obtained in the downstream subbasin, where changes were even greater. As a result of the reduced runoff and evapotranspiration, utilization of water resources was more efficient and ecological environment was improved under the CCFGP policy. Our results indicate the CCFGP resulted in a favorable ecological impact and should therefore be maintained. 相似文献
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以可持续发展相关理论为基础,利用系统工程的理论和方法建立了河北省县域可持续发展指标体系及其评价标准,并在全省范围应用,对全省136个县(市)可持续发展能力做出了评价。结合评价结果,阐述了河北省县域可持续发展能力的特征,提出了河北省县域可持续发展的方向和思路。 相似文献
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