Evolution characteristics and risk of ecological drought in the Jinghe River Basin, Northwest China

ABSTRACT Mastery of the change trend and migration characteristics of ecological drought and risk can provide reference for drought resistance and disaster reduction strategies, water security, and ecological protection in arid and semiarid areas. This study focuses on the Jinghe River Basin during the 1990–2020 period and adopts a three-dimensional perspective to investigate the spatiotemporal evolution characteristics of ecological drought. Specifically, the drought barycenter model, standard deviation ellipse method, and drought patch identification method are integrated to systematically analyze (1) the migration trajectories of ecological drought barycenters and (2) the dynamic evolution patterns of ecological drought patches. Furthermore, a quantitative evaluation method is developed based on multi-source data fusion, through which evaluations of ecological drought risks across the basin are conducted. The results indicated that the spatial distribution range of ecological drought in the basin exhibited a decreasing trend and the time scale of ecological drought had significant interdecadal variation characteristics. The ecological drought barycenters were mainly distributed in the northern part of the basin, demonstrating a northeast-to-southwest zonal distribution. The ecological drought risk areas showed a ‘point-belt’ pattern of difference between north and south, and a continuous southward trend in general, with the highest value reaching 0.46.