1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau; Northwest A&F University; Yangling China
2. Institute of Soil and Water Conservation; Chinese Academy of Sciences and Ministry of Water Resources; Yangling China
3. Wondo Genet College of Forestry and Natural Resources; Hawassa University; Shashemene Ethiopia
4. Center of CEF/ESCER, Department of Biological Science; University of Quebec at Montreal; Montreal Quebec Canada