Spatiotemporal Analysis and Prediction of Water Resource Vulnerability in the West-Flowing Songhua River Basin, China

Existing research on water resource vulnerability typically employs evaluation systems that rely on a singular indicator, which exacerbates the cumulative error effect. This study constructs an evaluation framework coupled with sensitivity, exposure, and adaptability grounded in the Soil and Water Assessment Tool (SWAT) model. Taking the west-flowing Songhua River Basin as the study area, the vulnerability is assessed from temporal and spatial perspectives, with the Sobol method employed to identify the key factors influencing basin vulnerability. The findings reveal that adaptability exhibits higher sensitivity in the evaluation function, and its interaction with sensitivity is significant. The slope factor is the most sensitive of evaluation parameters, followed by net primary productivity data for vegetation. Furthermore, the cellular automata (CA)-Markov model provides a detailed characterization of the spatial distribution and dynamic evolution of local water resource vulnerability in the basin. The water resource vulnerability is predicted to reach 0.26 and 0.32 in 2022 and 2026, respectively, and is slowly escalating. This study provides valuable insights into the water resource vulnerability evaluation system for the basin and provides a reference for future management and sustainable development of the basin’s water resources.