1. School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
2. Survey Engineering Company, China Energy Engineering Group, Yunnan Electric Power Design Institute Co., Ltd, Kunming 650500, China
3. Chongqing Branch, China Three Gorges Construction Engineering Corporation, Chongqing 401320, China
4. School of Ecology and Environment, Ningxia University, Yinchuan 750021, China
5. Yangchangwan Coal Mine of Ningxia Coal Industry Co., Ltd, China Energy Group, Lingwu, Ningxia 751411, China