1. School of Geography and Ocean Science, Nanjing University, Nanjing 210023, China
2. Key Laboratory of Virtual Geographic Environment (Ministry of Education of PRC), Nanjing Normal University, Nanjing 210023, China
3. Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology, Nanjing University, Nanjing 210023, China
4. Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing University, Nanjing 210023, China
5. International Research Center of Big Data for Sustainable Development Goals, Beijing 100094, China