1. Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing, Jiangsu 210023, China
2. School of Geography Science, Nanjing Normal University, Nanjing, Jiangsu 210023, China
3. Laboratorio de Geoquímica Orgánica, Instituto de Investigacións Mariñas (IIM), 16 Consejo Superior de Investigaciones Científicas (CSIC), Vigo 36208, Spain
4. School of Marine Science and Engineering, Nanjing Normal University, Nanjing, Jiangsu 210023, China
5. State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, Jiangsu 210023, China
6. Key Laboratory of Virtual Geographic Environment, Ministry of Education, (Nanjing Normal University), Nanjing, Jiangsu 210023, China