1. Faculty of Geomatics, East China University of Technology, Nanchang 330013, China
2. Key Laboratory of Watershed Ecology and Geographical Environment Monitoring, NASG, Nanchang 330013, China
3. Key Laboratory for Digital Land and Resources of Jiangxi Province, Nanchang 330013, China
4. Department of Land Surveying and Geo-Informatics, The Hong Kong Polytechnic University, Hong Kong, China
5. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China