Quantification of Coupling Relationship Between Urban Slope Climbing and Ecological Environment Quality in the Yangtze River Economic Belt and Its Influencing Factors

Slope climbing of urban expansion (SCE), as a form of urbanization, has increasingly significant impacts on urban development. Unsustainable slope climbing of urban expansion can harm the natural environment, thereby affecting human production and living conditions. Using a coupled coordination model and the geographically weighted regression (GTWR) model, leveraging night light remote sensing data and ecological environment quality index model, this study investigated the coupling relationship between urban expansion and ecological environment quality and its influencing factors in the Yangtze River Economic Belt of China from 2000 to 2020. The results indicate that from 2000 to 2020, the intensity of urban slope climbing in the Yangtze River Economic Belt showed a fluctuating upward trend, with the slope climbing intensity being most significant in Chongqing Municipality and Kunming of Yunnan Province. Overall, the ecological environment quality exhibited an upward trend, with over 80% of the study area maintaining stable or improved ecological quality. There is a certain spatial correspondence between ecological environment quality and urban slope climbing. Although these two aspects of development demonstrate a high degree of coordination, fluctuations still occur during the development process. Further research on the coupling coordination relationship between the two revealed that population density has a negative impact on coupling coordination in the eastern region, and technology expenditure in eastern coastal cities has shown a negative trend over time. To ensure the continued increase in the proportion of highly coordinated areas in the future, eastern coastal cities in the study region could prioritize ecological civilization construction, strengthen urban construction and development planning, adjust influencing factors, and ensure the coordinated development of urban growth with ecological environment quality.