Study On The Mechanism Of Regional Water Ecology And Water Environment Security

In recent years, with the advancement of science and the development of socio-economy, the requirement of water resources is increasing, the crisis of security faced by the water ecology and water environment is serious increasingly. As an integrative system, the structure of regional water ecology and water environment system with many influencing factors, is complicated and becoming the key problem of eco-environment system, including assessment index system and comprehensive evaluation.Based on the conceptual model of pressure-state-response, an assessment index system of regional water ecology and water environment security is set up, including many indicators, such as society economy environment and landscape ecology. On the basis of comprehensive understanding of the concept of water ecology and water environment security, fuzzy optimization model for evaluation regional water ecology and water environment security is established upon multi-objective and multilevel fuzzy optimization theory. In this paper, the entropy method is adopted to confirm the weight of each index, the virtue of which is full use of the value of each index in counting its weight and which makes difference between each index revealed in schemes comparison. With the combination of hierarchical evaluation index system of regional water ecology and water environment security and the model established above, the mechanism of regional water ecology and water environment security is studied.With the practical case of Jiangsu area in Taihu watershed, from two kinds of watershed scale, the regional water ecology and water environment security are evaluated by the multi-objective and multilevel fuzzy optimization model and entropy method. The result indicates that, the third class area in regard to water ecology and water environment security from good to poor in sequence are: Huxi and Taihu area Hangjiahu area and Wuyang area, and the fourth class area in regard to water ecology and water environment security from good to poor in sequence are: Taihu areaWuchengxiyuqu area Huxi area . Punan area and Yangchengdianmao area. In addition, through the correlation analysis between the security index of the fourth class area and the index of water quality, their negative correlation indicates that the comprehensive evaluation result of regional water ecology and water environment security is reasonable. At last, two scenarios, as the business as usual(BAU) and the towards sustainable development(TSD) scenario, are simulated to predict the development of the water ecology and water environment security in the fourth class area. The simulation suggested that the security situation of TSD is improved obviously. In conclusion, it is necessary to take some measures to ensure the water ecology and water environment security, following the theory of sustainable development.