1. Key Laboratory of Virtual Geographic Environment, Ministry of Education, Nanjing Normal University, Nanjing, People’s Republic of China
2. Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, People’s Republic of China
3. Nanjing Land and Resources Information Center, Nanjing, People’s Republic of China
4. School of Earth Science and Engineering, Hohai University, Nanjing, People’s Republic of China