Emergy Analysis and Sustainability Assessment of Ecological-economic System in Hunan Province

Based on emergy analysis,changes and trends of 10 indicators in Hunan province in 1999~2006 are gotten,such as Emergy investment ratio,Net emergy yield ratio,Environmental Loading ratio,Emergy dollar ratio,Emergy density,and Emergy per capita,Fraction of emergy used from electricity,Population carrying capacity,Emergy-based for sustainable index,Fraction of emergy used from rejectamenta.And a quantitative and comparative research was carried out by comparing different countries and districts to Hunan province in China in 2003 with selective indices.The results show that:(1) Although socio-economic level of Hunan rising,it is backward and is in the middle reaches in Chinese provinces and municipalities on the whole,and the way of developing economy and raising people's living standards is still very long.(2) Hunan also belongs to the ecological-economic region of resources-outputting,need to change this situation as soon as possible.(3)It should be controlled to expert energy-consuming products and environmental-contaminating products,and efforts to develop hydropower,appropriately restrained population growth,following the principle of maximum power to improve sustainable development of ecological-economic system by pressures on resources and environment in Hunan province.