1. State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, P. R. China
2. University of Chinese Academy of Sciences, Beijing 100049, P. R. China
3. Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, P. R. China
4. Institute of Pesticide and Environmental Toxicology, Zhejiang University, Hangzhou 310058, P. R. China