1. Northwest Institute of Historical Environment and Socio-Economic Development, Shaanxi Normal University, P.R. China
2. Department of Geography, Faculty of Social Sciences, Hong Kong Baptist University, P.R. China
3. School of Geographic Sciences, East China Normal University, P.R. China
4. State of Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, P.R. China
5. Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, P.R. China
6. Guangdong Provincial Key Laboratory of Conservation and Precision Utilization of Characteristic Agricultural Resources in Mountainous Areas, School of Chemistry and Environment, Jiaying University, P.R. China