1. College of Environmental Science and Engineering, China West Normal University , Nanchong 637009 , China
2. Nanchong Ecological and Environmental Monitoring Central Station of Sichuan Province , Nanchong 637000 , China
3. Department of Languages and Literatures, North Sichuan College of Preschool Teacher Education , Guangyuan 628017 , China
4. College of Life Science, China West Normal University , Nanchong 637009 , China