Coupling and coordination analysis in urban agglomerations of China: Urbanization and ecological security perspectives

Along with China's rapid urbanization development process, the severe ecological security problems which brought by the urbanization related activities has gradually caused academic and public discussion. To reach the high-quality development goals set by central government decisions in China, it is necessary to clarify the relationship between urbanization and ecological security, which can provide guidance to explore the path of coordination. On the basis of three major urban agglomerations in China, this paper constructs the comprehensive evaluation system of urbanization and ecological security through multi-source data. By using the Entropy-weight TOPSIS method, cities' urbanization and ecological security levels are calculated. Through the coupling coordination model, the coordination levels between urbanization and ecological security were also analyzed. At the end, Through Kernel estimation and the Markov chain method, the relative-absolute differentiation and the overall evolution trend of the coordination development were also estimated. The research results indicate the following: (1) The core cities' urbanization and ecological security level in the region are relatively high, while the peripheral cities are generally low; (2) The coordination development in the urban agglomerations revealed as a relatively steady progress; (3) The aggregation effect gradually emerged under the coordination development periods in the urban agglomerations; (4) The overall coupling coordination development in urban agglomerations has the possibility of club convergence.