Study on the coupling relationship of rapid urbanization and ecological environment with the case of Changzhou city

This paper explores the interactive process and quantitative mechanisms between the rapid urbanization and ecological environment in Changzhou city from 1986 to 2007. Based on constructing the comprehensive indexes of urbanization level and ecological quality using Analytic Hierarchy Process (AHP)method and Press-State-Response (PSR) model, the coupling relationship between the rapid urbanization and ecological environment was analyzed by using Environmental Kuznets Curve(EKC) theory and the Granger Causality Test Method. It is concluded that: (1) the change of ecological environment comprehensive quality complies with the Environmental Kuznets Theory at 5 years interval. (2)The comprehensive level of urbanization shows Granger Causality between comprehensive ecological quality and ecological state while there is no relationship of Granger Causality between the comprehensive level of urbanization and the pressure and response of the ecological environment. (3)Environmental effects result from not only the urbanization process, but also include the comprehensive quality of the ecological environment, ecological pressure and response. The negative impacts of urbanization have less effect than the positive changes in the ecological environment itself, and changes in comprehensive ecological quality and pressure are largely stable, but changes in the undulation of ecological response will gradually be intensified.