1. School of Geographic Science, Fujian Normal University, Fuzhou, Fujian 350007, China
2. Information Management & Engineer Department, Fujian Commerce College, Fuzhou 350012, China
3. Cultivation Base of State Key Laboratory Humid Subtropical Mountain Ecology, Fuzhou 350007, China
4. School of Civil and Environmental Engineering, Nanyang Technological University, Nanyang Ave., 639798, Singapore