Flood risk assessment under land use dynamics during 2000–2020 in the yellow river basin, China

Floods are one of the most devastating natural disaster events globally and are strongly influenced by land use changes. This study crafted a holistic “hazard-sensitivity-vulnerability-restorability” flood risk assessment framework, integrating data from land use, natural environment, and socioeconomic factors. Using the Yellow River Basin (YRB) in China as an example from 2000 to 2020, it analyzed the spatiotemporal evolution of land use structure and flood risk, revealing their cluster pattern based on quantitative land use structure indices and flood risk index. Key findings include: (1) A gradient pattern of increasing flood risk from northwest to southeast in the YRB, with an overall trend of significant decrease followed by rebound from 2000 to 2020. (2) By 2020, land use homogenization occurred in middle-basin deserts due to grassland restoration, contrasting with down-basin fragmentation driven by built-up land expansion. (3) Global spatial correlation showed flood risk positively linked to cropland, built-up land and forest significantly but negatively associated with grassland significantly, highlighting land use trade-offs in flood mitigation. (4) Local spatial correlation revealed a “cold west (low risk - low structure index) vs. hot east (high risk – high structure index) " differentiation, emphasizing zoning-based management needs. The study provides actionable insights for balancing flood resilience and land resource sustainability in the YRB. The proposed framework offers a transferable methodology for large river basins globally, particularly in regions facing coupled pressures of climate change and rapid urbanization.

Graphical abstract