2 Study area
Yan’an belongs to Shaanxi Province and is located in the central of the Loess Plateau of China, with a total area of about 37,000 km2 (Figure 1). In 2018, the resident population of Yan’an was about 2.5294 million, and the urbanization rate reached 62.31%. The terrain of Yan’an is high in the northwest and low in the southeast, with an average elevation of about 1,200m. Yan’an has a typical temperate continental monsoon climate with concentrated precipitation. Special geological and climatic conditions are important factors that cause soil erosion in this city. In recent years, due to the implementation of GFG, the vegetation coverage in Yan’an has significantly improved, and soil erosion has also been significantly controlled (Government Website of Yan’an, 2019).
[Figure 1 near here]