Multiscale Spatiotemporal Characteristics of Soil Erosion and Its Influencing Factors in the Yellow River Basin

Abstract

Soil erosion is an important ecological and environmental problem in the Yellow River Basin (YRB), which restricts the sustainable development of the YRB. Based on the Revised Universal Soil Loss Equation (RUSLE) and Optimal Parameters-based Geographical Detector (OPGD), this study discusses the multiscale spatiotemporal characteristics of soil erosion and its influencing factors in the YRB. The results show that: (1) The average values of soil-erosion modulus of the YRB in 2000, 2005, 2010, 2015, and 2020 was 1877.69, 1641.59, 1485.25, 844.84, and 832.07 t·km−2·a−1, respectively, and the areas with severe soil erosion are mainly concentrated in the three provinces of Gansu, Shanxi and Shaanxi, showing a belt-like trend in the northeast-southwest as a whole. (2) From 2000 to 2020, the q value of soil erosion influencing factors in the YRB showed a downward trend. From the YRB scale to the county scale, the q value of the influencing factors showed an increasing trend. Among them, fractional vegetation cover (FVC), landform type, and LU/LC have strong explanatory power for soil erosion in the YRB. FVC explains about 15% of soil erosion, and the interaction between FVC and landform explains up to 35% of soil erosion. (3) The ability of human activities (LU/LC, FVC) to influence soil erosion is increasing, and this feature is more pronounced at small scales. The conclusion of this study can be summarized as managers should pay attention to the role of human activities in the YRB for soil erosion, especially at small scales, in order to formulate lower-cost and targeted soil and water conservation measures.