[Spatio-temporal Differentiation and Its Driving Mechanism of Ecological Vulnerability in Sichuan Province]

Sichuan Province is widely recognized as a highly representative and complex geomorphic region, where the structural contradiction of the ecological environment is prominent. The in-depth study of the spatio-temporal differentiation characteristics and identification of the driving mechanism of ecological vulnerability from a spatial differentiation perspective in Sichuan Province is of great importance to the regional ecological environment management and protection. Here, the Sichuan Province was selected as the research area and 15 indicators from the natural and social environment aspects were used to establish an evaluation system based on the "sensitivity-recovery-pressure" framework. The spatio-temporal differentiation characteristics of the ecological vulnerability in the study area were comprehensively analyzed by spatial principal component analysis, spatial autocorrelation, and optimal parameters-based geographical detector. Additionally, the driving mechanism behind the spatial differentiation of ecological vulnerability was revealed through the optimization of continuous variable discretization. The results showed that： ① From 2000 to 2020, a gradual decrease was observed in the ecological vulnerability index from 0.422 to 0.398, suggesting an overall upward trend in the ecological environment. The general ecological vulnerability level was moderately fragile, with a slightly better trend over time. A distinct pattern of "high in the east and low in the west," was observed indicating significant regional differences. ②The spatial pattern of ecological vulnerability in the Sichuan Province remained relatively stable and exhibited strong spatial agglomeration characteristics. High-high clustering areas were mainly distributed in the rapid development of urbanization and densely populated eastern region and low-low clustering areas were primarily distributed in the western, northwestern, and southwestern regions with a good ecological environment and a sparse population. ③The major driving factors of ecological vulnerability were land use, habitat quality, and biological abundance in Sichuan Province. Interactions among these factors amplified their impact on ecological vulnerability. Consequently, ecological vulnerability was the result of the combined effects of various factors, requiring the implementation of customized strategies for the protection and management of the ecological environment.