1. Geography Department, Vinh University, Vinh 460000, Vietnam
2. NPO Ecology and Regional Culture Studies Association, Ohmihachiman 523-0821, Japan
3. Lago Co., Ltd., Ohmihachiman 523-0821, Japan
4. School of Agriculture and Natural Resources, Vinh University, Vinh 460000, Vietnam
5. Doctor Course, Vinh University, Vinh 460000, Vietnam