Optimizing Cross-Regional Mobility Contributes to the Metacoupling Between Urbanization and the Environment for Regional Sustainability

As a result of rapid urbanization, ecological and environmental problems have become increasingly severe. Sustainable regional development requires a balance between urbanization and the environment. With the intensification of economic globalization and technological innovation, the flow of various elements such as population, capital, information, and resources has gradually blurred administrative boundaries, leading to new cross-scale evolutionary characteristics in this relationship. However, existing studies have primarily been conducted at the local scale and have failed to capture the impact of cross-regional element flows on the relationship between urbanization and the environment. Under the metacoupling framework, this study improves the existing methodological framework by integrating the flows of production factors and ecosystem service (ES) to characterize the metacoupling between urbanization and the environment in the Chengdu-Chongqing urban agglomeration (CCUA). A new comprehensive index system for urbanization and environment was constructed, considering the cross-regional flow of multiple factors. The Coupling Coordination Degree model was employed to calculate the degree of intracoupling, pericoupling, and telecoupling between urbanization and the environment. The Geodetector model was used to determine the effects of local, adjacent, and distant flows of production and ES factors on these degrees. The results show that the intracoupling between urbanization and the environment was low, while the pericoupling and telecoupling increased from local to distant scales. Production factor and ES flows were the common factors affecting the metacoupling between urbanization and the environment, but population flows and capital flows were more strongly explained at the local scale, and ES flow was more strongly explained at the adjacent and distant scales. Based on these results, a systematic understanding of the complex relationship between urbanization and environment is provided, which in turn provides a basis for decision making regarding the coordinated and sustainable development of urban and ecological management in the CCUA as well as other urban agglomerations.