1. State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, Xinjiang, China
2. Research Centre for Ecology and Environment of Central Asia, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, Xinjiang, China
3. University of Chinese Academy of Sciences, Beijing, Peking China
4. Department of Geography, Ghent University, Ghent, Belgium
5. Sino-Belgian Joint Laboratory of Geo-Information, Ghent, Belgium
6. Sino-Belgian Joint Laboratory of Geo-Information, Urumqi, Xinjiang, China