Sustainable livelihood theory provides a comprehensive framework for understanding the interactions between livelihoods of peasant households and regional environment change in low-income areas. Based on field survey ...Sustainable livelihood theory provides a comprehensive framework for understanding the interactions between livelihoods of peasant households and regional environment change in low-income areas. Based on field survey and 946 questionnaires from peasant household conducted in the case study area of Zhaotong, Yunnan Province, the paper has analyzed the basic characteristics of the rural livelihoods, including the asset base status, the income-generating activities, the energy consumption pattern, and the fertility behavior, in the upper reaches of the Changjiang (Yangtze) River. The micro-level findings show the conflicts among extensive agricultural development models, rural energy consumption structures heavily relying on biomass and the environment protection. The conversion of cropland to forest and grass program(CCFGP) has exerted an important influence on the livelihoods of the peasant households, but its design has given little considerations to their long-term livelihood sources, which will affect its sustainability to a great extent. From the perspective of sustainable livelihoods framework, the objectives that must be addressed in the ecological shelter construction in the upper reaches of the Changjiang River should include, first, facilitating access of peasant households to credit, technology and public services, second, encouraging the peasant households to adopt agricultural technology with environmental benefits and strengthen resources-conserving investments, and third, paying close attention to the rural energy problems and the long-term livelihood sources of the households with CCFGP. Given the weak asset base and difficulties of livelihood strategies shift, ecological shelter construction in the upper reaches of the Changjiang River will take a long time.展开更多
The Fluorine release rate of coal, clay of different Fluorine content, and coal mixed with clay used by resident households were studied by using the ion selective electrode (ISE) and solidoid balance methods, and t...The Fluorine release rate of coal, clay of different Fluorine content, and coal mixed with clay used by resident households were studied by using the ion selective electrode (ISE) and solidoid balance methods, and the degree of influence on Fluorine pollu- tion generated by coal and clay was analyzed according to the proportion characteristics of coal used by resident households. The results show that the Fluorine release rate of coal is more than 95% during combustion; The Fluorine release rate of clay is more than 99%; The Fluorine release rate of coal mixed with clay is between 56.44% and 96.64%, and the average value is 76.68%. The clay as a binder for fine coal is one important source of Fluorine pollution caused by coal-combustion in Zhaotong, Yunnan Province. When the Fluorine content of coal is less than 80 mg/kg, the F[uodne amount released from clay (in which Fluorine content is more than 530 mg/kg) is more than 50% of the total Fluorine amount released from coal and clay during coal-combustion. The Fluorine amount released from clay (in which Fluorine content is more than 1 000 mg/kg) is more than 70% of total Fluorine amount released from coal and clay during coal-combustion.展开更多
基金Under the auspices of the Fund Project of Ministry of Science and Technology of the People's Republic of China (No.2005BA807B05)
文摘Sustainable livelihood theory provides a comprehensive framework for understanding the interactions between livelihoods of peasant households and regional environment change in low-income areas. Based on field survey and 946 questionnaires from peasant household conducted in the case study area of Zhaotong, Yunnan Province, the paper has analyzed the basic characteristics of the rural livelihoods, including the asset base status, the income-generating activities, the energy consumption pattern, and the fertility behavior, in the upper reaches of the Changjiang (Yangtze) River. The micro-level findings show the conflicts among extensive agricultural development models, rural energy consumption structures heavily relying on biomass and the environment protection. The conversion of cropland to forest and grass program(CCFGP) has exerted an important influence on the livelihoods of the peasant households, but its design has given little considerations to their long-term livelihood sources, which will affect its sustainability to a great extent. From the perspective of sustainable livelihoods framework, the objectives that must be addressed in the ecological shelter construction in the upper reaches of the Changjiang River should include, first, facilitating access of peasant households to credit, technology and public services, second, encouraging the peasant households to adopt agricultural technology with environmental benefits and strengthen resources-conserving investments, and third, paying close attention to the rural energy problems and the long-term livelihood sources of the households with CCFGP. Given the weak asset base and difficulties of livelihood strategies shift, ecological shelter construction in the upper reaches of the Changjiang River will take a long time.
基金Supported by the National High-Tech Research and Development Program of China(2006AA06Z380)the National Natural Science Fundation of China(40872210)Western Key Fund(90202017)
文摘The Fluorine release rate of coal, clay of different Fluorine content, and coal mixed with clay used by resident households were studied by using the ion selective electrode (ISE) and solidoid balance methods, and the degree of influence on Fluorine pollu- tion generated by coal and clay was analyzed according to the proportion characteristics of coal used by resident households. The results show that the Fluorine release rate of coal is more than 95% during combustion; The Fluorine release rate of clay is more than 99%; The Fluorine release rate of coal mixed with clay is between 56.44% and 96.64%, and the average value is 76.68%. The clay as a binder for fine coal is one important source of Fluorine pollution caused by coal-combustion in Zhaotong, Yunnan Province. When the Fluorine content of coal is less than 80 mg/kg, the F[uodne amount released from clay (in which Fluorine content is more than 530 mg/kg) is more than 50% of the total Fluorine amount released from coal and clay during coal-combustion. The Fluorine amount released from clay (in which Fluorine content is more than 1 000 mg/kg) is more than 70% of total Fluorine amount released from coal and clay during coal-combustion.