Spatiotemporal Evolution of Soil Erosion and Its Driving Mechanism in the Mongolian Section of the Yellow River Basin

Abstract

Soil erosion is a popular environmental issue that threatens sustainability. Influenced by multiple factors, such as climate, soil, and terrain, Baotou City, which is in the Bohai Sea Economic Circle and the Economic Belt along the Yellow River, has a severe ecological environment. In this study, revised soil and soil wind erosion equations were used to evaluate the soil erosion dynamics in Baotou City, and the potential driving factors of soil erosion were further investigated. Results showed that from 1990 to 2020, the water erosion modulus in Baotou City increased first, decreased, and then increased, with great fluctuations in annual changes. The wind erosion modulus decreased continuously, with a small fluctuation in annual changes. Water erosion in 2020 was more severe, with 4840.5 km2 added to the desert steppe and 1300.5 km2 reduced in the Yellow River Basin. The extent of wind erosion was significantly reduced, and the phenomenon of wind erosion improved. Meteorological factors are the primary factors that influence soil water erosion and soil wind erosion. Meanwhile, adverse climate changes can alter physical and chemical soil properties and vegetation coverage, thereby indirectly influencing soil erosion. With the implementation of the Beijing–Tianjin sandstorm source control, the farmland return to forest project, the ecological restoration and protection project at the southern and northern foothills of Daqingshan Mountains, grazing prohibition, and rotation grazing—including grassland awards, subsidies, and other policies and systems during this period—the overall deteriorating trend of the grassland ecological environment in Baotou was contained, grassland ecological system functions were improved, wind and sand erosion was prevented, biodiversity was maintained, and the ecological service functions of soil and water conservation were guaranteed.