Key Laboratory of Geographic Information Science(Ministry of Education),School of Geographic Sciences,East China Normal University,Shanghai 200241,China

Institute of Surface-Earth System Science,School of Earth System Science,Tianjin University,Tianjin 300072,China

Technical Centre for Soil,Agriculture and Rural Ecology and Environment,Ministry of Ecology and Environment,Beijing 100012,China

College of Environmental Natural Resource Sciences,Zhejiang University,Hangzhou 310058,China

State Key Laboratory of Pollution Control and Resources Reuse,School of the Environment,Nanjing University,Nanjing 210023,China

School of Environmental Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China