1. Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing, China
2. State Key Laboratory Cultivation Base of Geographical Environment Evolution (Jiangsu Province), Nanjing, China
3. Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, China
4. College of Earth and Environmental Sciences, Lanzhou University, Lanzhou, China
5. School of Geographic and Biologic Information, Nanjing University of Posts and Telecommunications, Nanjing, China