Improvement in the evaluation model of water resources carrying capacity of urbanized area base on Fuzzy theory

Water resources carrying capacity (WRCC) is an index, which reflects the supporting ability of the water resources system for sustainable society development. And it is the foundational measurement of water resources security, also it is a complex system which involves social-economic system, water resources system and ecological environment system. Pointing to the problems on vague concept about subjection degree in the evaluation model of water resources carrying capacity base on entropy, the author proposes determination methods of subjection degree and eigenvalue of level from Fuzzy. Eigenvalue of level can be synthesized from the influence of every subjection degree of level to evaluation results. A case study is given by using this model. The results compared with those of other approach shows that the model possesses some clear mathematic and physical conception and it is simple, practical and accurate. And it has higher resolution and sensitivity and reliability.