1. a Key Laboratory of Water Cycle and Related Land Surface Processes , Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences , Beijing , 100101 , China
2. b Key Laboratory of Agricultural Information Technology , Ministry of Agriculture , Beijing , 100081 , China
3. c College of Resources and Environment, University of Chinese Academy of Sciences , Beijing , 100049 , China
4. d Baoding Water and Soil Conservation Station , Baoding , Hebei , 074200 , China
5. e German Remote Sensing Data Center, DFD, German Aerospace Center, DLR , 82234 , Wessling , Germany
6. f Institute of Photogrammetry and Remote Sensing, Vienna University of Technology , 1040 , Vienna , Austria