Emergy Analysis The Value Of East Juyan Lake Wetland Eco-environment System

East Juyan Lake is one of the main beneficiaries of Heihe River Diversion Project. It’s significant to value the Lake for ensuring the project smoothly and gaining the identify with it and improving people’s initiation. Under the Yellow River Hydraulic Research Institute fund "Based on Emergy theory to evaluate East Juyan Lake wetland value" numbered HKY-JBYW-2011-8, the value of the East Juyan Lake wetland eco-environment system is studied dynamically from three aspects:social, economic and ecological. The main contents and results are:East Juyan Lake wetland’s dynamic characteristics are drawn firstly. According to the historic and modern characteristics about the water area, the water quality and the vegetation cover on the wetland, the reason for its shrinking and drying up is to be shown, and then its developing progress is divided into three stages what building a time framework for the further study.Secondly, the Energy transfer and conversion process in the eco-environment system is researched and the energy flow diagram is appeared based on the principle of building energy network. After that, the article applies the solar emergy transformation calculation method to yield the emergy transformation for the East Juyan Lake water which is the basis for the emergy value of the system.Thirdly, the evaluation index system is built and quantified with the emergy theory. Combining the Ecologic Economics Theory with the effect of wetland function, the paper builds the evaluation index system for the service function of the wetland ecological economic system, uses the emergy theory to estimate the value during the different times, and analyzes the dynamic features which provide a lot of data for knowing the wetland.Finally, a model is made in order to consider the system development level synthetically. The research makes use of the other typically sixteen wetlands’ emergy coefficient to get an evaluation index set for studying comprehensively thevariation of the level. The result shows that the value of the wetland eco-environment system is:50years is6.11+21sej,80years isl.13E+20sej, the dry period is2.48+18sej and the restoration period is1.84E+20sej; The correlative degree is:50years is0.169,80years0.038, the dry period is0.0007and the restoration period is0.034. According to the change of the value and the correlative degree, we can know that the capability of East Juyan Lake wetland eco-environment system is very great, but after50years, the capability is tapering until it died, even though the level is raising in the restoration.