1. a School of Earth Sciences, Yunnan University, Chenggong District, Kunming, Yunnan Province, China
2. b Institute of International Rivers and Eco-security, Yunnan University, Chenggong District, Kunming, Yunnan Province, China
3. c Kunming surveying and Mapping Management Center, Room 502, Building 2, municipal administrative center, Chenggong New District, Kunming, Yunnan Province, China
4. d Kunming Surveying and Mapping Institute, No. 16, Renmin Lane, East Renmin Road, Kunming, Yunnan Province, China