1. State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology; Chinese Academy of Sciences; Nanjing Jiangsu 210008 China
2. University of Chinese Academy of Sciences; Beijing 100049 China
3. Department of Environmental Remote Sensing and Geoinformatics; University of Trier; D-54286 Trier Germany
4. College of Landscape Architecture; Nanjing Forestry University; Nanjing 210037 China