1. Key Laboratory of Western China’s Environmental Systems (Ministry of Education) and Key Laboratory for Environmental Pollution Prediction and Control, Gansu Province, College of Earth and Environmental Sciences, Lanzhou University, Lanzhou
730000, P. R. China
2. Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Institute of Salt Lake, Chinese Academy of Sciences Xinning Road 18 Chengxi District Xining 810008 P R China
3. College of Resources and Environment, Chengdu University of Information Technology, Chengdu 610225, P. R. China