Comparative Analysis on the Spatiotemporal Changes of Vegetation and Drivers in Inland River Basins of the Hexi Corridor, China

Vegetation change is an important indicator of ecological stability. The Heihe River Basin (HHRB), Shiyang River Basin (SYRB), and Shule River Basin (SLRB) in the Hexi Corridor of China have an arid climate and are ecologically fragile. Understanding vegetation changes and driving factors can guide the implementation of ecological restoration measures. The spatiotemporal characteristics of vegetation in the inland river basins of the Hexi Corridor during 1987-2023 were analyzed based on the NDVI using Landsat data, and the impacts of the driving factors on vegetation changes and spatial distributions were explored using residual analyses and Geodetector model. NDVI showed a spatial distribution pattern of high in the upper reaches and oases and low in the lower reaches. The spatial distribution of vegetation in the upper, middle, and lower reaches is influenced by different factors. Vegetation is most influenced by temperature and precipitation in the upper reaches of the basins, by population density in the middle reaches, and by a combination of natural factors and human activities in the lower reaches. NDVI trends indicate increases in the upper and middle reaches of the basins and the lower reaches of the HHRB, while the lower reaches of the SYRB and SLRB show decreases. The increasing trend is mainly driven by climate change, whereas the decrease is primarily due to human activities, climate change, or a combination of both. These findings are significant for vegetation growth in the Hexi Corridor's inland river basins and for the ecological management and sustainable development of areas.