1. Key Lab. of Pollution Processes and Environmental Criteria, Ministry of Education; College of Environmental Science and Engineering, Nankai Univ.; Tianjin 300071 China
2. State Key Lab. of Urban and Regional Ecology; Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences; Beijing 100085 China
3. Univ. of California; Riverside
4. Dep. of Environmental Sciences; Univ. of California; Riverside CA 92521