Research on the Spatio-temporal Coupling of Urbanization and Ecological Environment Quality in the Middle Section of the Tianshan Mountains

To delve into the spatiotemporal coupling between urbanization levels and ecological environment quality in the middle section of the Tianshan Mountains, the study constructed composite indices representing urbanization levels across four dimensions: population, economic, spatial, and transportation, and developed ecological remote sensing indices across five aspects: greenness (NDVI), wetness (WET), heat (LST), dryness (NDBSI), and salinity (SI-T), serving as proxies for ecological environment quality. Utilizing a coupling coordination degree model, the study explored the spatiotemporal coupling relationship between urbanization level and ecological environment quality, and analyzed different patterns of change from 2014 to 2022. Results indicate: (1) The overall comprehensive urbanization level in the middle section of the Tianshan Mountains is relatively low but developing rapidly, with high urbanization concentrated mainly in urban clusters on the northern slope of the Tianshan Mountains. (2) Ecological environment quality is generally poor, with only about 30% of areas reaching a "medium" or higher quality level over the years, though, the central and northwestern regions exhibit relatively better ecological conditions, and with most areas showing stable or slow improvement trends.(3)The overall coupling coordination degree in the middle section of the Tianshan Mountains is relatively low, showing a slow increasing trend, but averaging in a severely imbalanced state. From 2014 to 2022, 7.96% of regions saw an increase in coupling coordination level, with 43.33% and 1.75% of areas respectively facing issues where urbanization development sacrificed ecological environment or urban development was constrained by ecological environment. In contrast, 0.86% of regions saw a decrease in coupling coordination level, with 43.34% of these areas experiencing severe constraint relationships leading to overall developmental imbalance, and 56.58% experiencing significant decreases in both urbanization levels and ecological environment quality.