Analysis of the coupling coordinated development of the Population–Water–Ecology–Economy system in urban agglomerations and obstacle factors discrimination: A case study of the Tianshan North Slope Urban Agglomeration, China

The rapid development of urban agglomerations faces a series of resource and environmental problems. Exploring the coupling relationship and coordination effect of the Population–Water–Ecology–Economy (PWEE) system in urban agglomerations is conducive to promoting the sustainable development of these regions. This study illustrates the interrelationship among these factors by examining the Tianshan North Slope Urban Agglomeration (TSNSUA). We constructed a comprehensive set of evaluation indicators for the PWEE system in the TSNSUA; based on the Entropy Weight Method and the Coupling Coordination Degree (CCD) Model, the Comprehensive Development Index (CDI) and CCD of the PWEE system were measured from 2005 to 2018. With the help of the Obstacle Degree Model, we diagnosed the obstacles to the coordinated development of PWEE system in the TSNSUA. The main results can be summarized as follows. During the study period, the comprehensive development level of the PWEE system in the TSNSUA showed an upward trend, and the coupling coordination effect was strengthening, the coupling coordination level changed from barely to good coupling coordination. The water resources and ecological subsystems have gradually overtaken the population and economic subsystems as the leading factors limiting the coordinated development of the PWEE system.