Spatiotemporal Patterns of Fractional Vegetation Cover and Their Associations with Climate and Land Cover in the Yarkant River Basin

The dynamics of arid inland river basins are closely associated with climate variability and human land-use activities, making long-term monitoring essential for understanding ecological responses and supporting sustainable water resource management. Based on annual fractional vegetation cover (FVC) FVC data from 2000 to 2023, this study investigated spatiotemporal dynamics, relative temporal variability, and selected explanatory variables of vegetation in the Yarkant River Basin using the Theil–Sen estimator and Hamed–Rao-modified Mann–Kendall trend test, the Coefficient of Variation (CV), temporal correlation analysis, the Hurst exponent, and the Geographical Detector model. The results showed that vegetation cover exhibited an overall greening trend with pronounced spatial heterogeneity. Medium- and high-coverage vegetation expanded from 6970.69 km2 and 3662.50 km2 in 2000 to 11,111.63 km2 and 6316.00 km2 in 2023, respectively, while extremely low vegetation cover decreased by more than 50%. The strongest FVC increases were mainly concentrated in oasis and riparian areas, whereas decreases in FVC and high relative temporal variability occurred primarily within the oasis–desert transition zone. Temporally, FVC exhibited a significant positive contemporaneous association with precipitation. Spatially, Land cover consistently exhibited the strongest spatial association with FVC (q = 0.715–0.745), and its interaction with climatic factors further enhanced vegetation differentiation (maximum interaction q = 0.785). Exploratory Hurst exponent analysis showed that H values exceeded 0.5 in 93.96% of the mapped area, indicating widespread persistent temporal behavior within the observed 2000–2023 FVC series. These findings provide insights into vegetation evolution and information relevant to vegetation and water-resource management in arid inland river basins.