Research On Ecosystem Health Evaluation Of West Lake In Hangzhou

The issue of "ecosystem health" appeared with the global ecological environment deterioration increasingly and the research on ecosystem health has become one of the most important issues in ecology fields. This paper draw lessons from the results of scholars study on ecosystem health evaluation, set foot on studying the ecosystem health evaluation of West Lake in Hangzhou.Firstly, establishing entropy fuzzy comprehensive evaluation model and entropy comprehensive index evaluation model, selecting the aquatic data of West Lake by routine measurement in the year of 2000, as to evaluated the ecosystem health status of L.Xiaonan, L.Wai, Youth Palace and L.Yue in West Lake, the two model got the same result: the health situation of L.Xiaonan was better than the others, and the result was accordance with the actual situation of West Lake, that showed the two models were feasible to evaluate the ecosystem health of West Lake. In addition, fuzzy comprehensive evaluation was more accord with actual applicative requirements. Furthermore, evaluated the ecosystem health of four seasons in different monitoring points with entropy fuzzy comprehensive evaluation model, it can be see that ecosystem health changing with seasons was different in different points from the result: the four seasons of L.Xiaonan were in healthy or very healthy; it was in health in winter of L.Wai, they were in common morbidity in summer and autumn of L.Wai, Youth Palace as well as summer in L.Yue, the other seasons of the three monitoring points were all in sub-healthy; and evaluated ecosystem health of the whole lake in the years of 2000 and 2003, the result showed: West Lake was in sub-healthy both in the year of 2000 and 2003, that meant the change of ecosystem health situation in West Lake was not obvious in the period of dredging.Fuzzy comprehensive evaluation extended the classic binary logic of "either this or that" to fuzzy logic of "both this and that", which can reflect the true stations of ecosystem, and got good effect using the method in the research, it can provide the scientific basis for sustainable development of West Lake.