1. College of Water Resources and Architectural Engineering, Northwest A&F University, Xianyang 712100, China
2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Water and Soil Conservation, Northwest A&F University, Xianyang 712100, China
3. Institute of Soil and Water Conservation, Northwest A&F University, Xianyang 712100, China
4. The UWA Institute of Agriculture and School of Agriculture and Environment, The University of Western Australia, LB 5005, Perth, WA 6001, Australia