Analysis of Spatiotemporal Variations in Vegetation Cover and Its Drivers in the Kuye River Basin, Middle Reaches of the Yellow River, China

Clarifying the dynamic changes in vegetation cover and the driving mechanisms under the combined influence of the natural environment and human activities is a crucial foundation for understanding the evolutionary processes of ecosystems in arid and semi-arid regions and for improving the effectiveness of ecological restoration. Taking the Kuye River Basin, a typical resource exploitation zone in the middle reaches of the Yellow River, as the research area, this study retrieved 30 m resolution annual maximum NDVI datasets from 1986 to 2020 to calculate the Fractional Vegetation Cover (FVC). Utilizing methods such as Theil–Sen slope analysis, Mann–Kendall significance test, Hurst exponent, stability analysis, geographical detector, and sensitivity index, this study systematically revealed the spatiotemporal patterns of vegetation change, future evolution trends, and the response mechanisms of FVC dynamics to multiple factors including climate, topography, and land use. The results indicated that from 1986 to 2020, FVC in the study area exhibited an overall increasing trend (0.0105 a−1), with the average FVC rising from 0.21 to 0.61. Regions with very low and low vegetation coverage continued to decrease, while areas with high and very high vegetation coverage showed significant increases, particularly in the very high vegetation coverage category, which experienced the largest growth (CV = 179.32%). The regions with moderate vegetation coverage demonstrated the highest stability (CV = 48.42%). Analysis of the driving mechanisms revealed that precipitation and land use types were the primary factors influencing changes in FVC, with land use demonstrating a more stable explanatory power (CV = 3.63%). Furthermore, the interaction between these two factors significantly enhanced the explanatory power related to vegetation changes. Sensitivity analysis indicated that the increase in forest and grassland effectively mitigated the negative impact of cropland on moderate to high coverage areas; industrial and mining land had a notable impact on very low coverage areas. It can be inferred that the Grain for Green program and the expansion of industrial and mining lands might generate differentiated impacts across diverse vegetation coverage classes. Future projections indicate that 91.19% of the region exhibits potential for FVC improvement in the future. However, a risk of sustained vegetation degradation exists in densely populated areas and regions with concentrated industrial and mining land. The study demonstrates that under the combined influences of climate change and land use adjustments, optimizing land use structures and coordinating ecological restoration with resource development are critical approaches to enhancing the stability of ecosystems in arid and semi-arid regions, as well as promoting sustainable regional ecological development.