Spatiotemporal Evolution of Eco-Environmental Quality in Sonid Left Banner: RSEI Assessment and Associations with Climatic and Anthropogenic Factors

This study assessed the spatiotemporal dynamics of eco-environmental quality (EEQ) in Sonid Left Banner from 2000 to 2025, using Landsat imagery and the remote sensing ecological index (RSEI) via Google Earth Engine. Theil–Sen slope, Mann–Kendall test, Hurst exponent, and Pearson correlation analysis were used to analyze trends and their associations with climatic and anthropogenic factors. Results showed that EEQ exhibited an overall improving trend, with a mean RSEI of 0.270 and an annual increase of 0.0022 a−1, though it remained at a fair grade with a spatial pattern of “regionally poor but locally improved.” Hurst exponent analysis has indicated that 75.35% of the study area will sustain improvement, while 17.03% faces continuous degradation risk. Climatic factors showed the strongest associations with RSEI: precipitation (r = 0.329) and humidity (r = 0.313) showed the strongest positive correlations, with a distinct north–south spatial gradient in their association patterns; temperature (r = 0.272) showed bidirectional correlation patterns; and wind speed (r = −0.197) was the primary negative correlated factor. Human activity intensity (HAI) was negatively correlated with RSEI (r = −0.128), with 7.8% of high-intensity development areas showing significant degradation. These findings reveal that moisture availability establishes the ecological baseline in semi-arid grasslands, while human activities modulate ecosystem change, informing targeted ecological restoration.