美国国家地理科研基金项目9336-13;四川省教育厅自然科学重点项目12ZA273;福州大学科技发展基金项目510211National Geographic Society Committee for Research and Exploration,USA Grant No.9336-13;Scientific Research Foundation of Education Department of Sichuan ProvinceGrant No.12ZA273;Science Foundation of Fuzhou UniversityGrant No.510211