Influencing factors and their interactions of water erosion based on yearly and monthly scale analysis: A case study in the Yellow River basin of China

Abstract. In the Yellow River basin, soil erosion is a significant natural hazard problem, seriously hindering the sustainable development of society. An in-depth assessment of soil erosion and a quantitative identification of the influencing factors are important and fundamental for soil and water conservation. The RUSLE model and geographical detector method were applied to evaluate and identify the dominant factors and spatiotemporal variability in the Yellow River basin. We found that topographical factors such as slope and surface roughness were the dominant factors influencing the spatial distribution of soil erosion in the Yellow River basin, while rainfall and vegetation were as follows. In the period of low rainfall and vegetation coverage, the interaction of rainfall and slope can enhance their impact on the distribution of soil erosion, while the combination of vegetation and slope was the dominant interacting factor in other periods. The dominant driving factors of soil erosion variability were affected by changes in rainfall, but the contribution decreased. The spatial and temporal heterogeneity of soil erosion on a monthly scale was higher, and July had the highest amount of soil erosion with a multi-year average of 12.385 ton/(km²·a). The results provide a better understanding of the relationships between soil erosion and its latent factors in the Yellow River basin. Given the temporal and spatial heterogeneity effects of geographical conditions, especially at the basin scale, policy-makers should form a collaborative environmental governance framework to minimize the risk of soil erosion.