1. Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization, Northeast Normal University, Jingyue Street 2555, Changchun, China
2. School of Psychology, Inner Mongolia Normal University, Hohhot, China
3. College of Life Science, Jilin Agricultural University, Changchun, China
4. Key Laboratory of Vegetation Ecology, School of Environment, Institute of Grassland Science, Northeast Normal University, Ministry of Education, Changchun, China