1. Center for Systems Integration and Sustainability, Department of Fisheries and Wildlife, Environmental Science and Policy Program, Michigan State University, East Lansing, MI 48824, USA
2. Department of Landscape Architecture, School of Design, Shanghai Jiao Tong University, Shanghai 200240, China
3. State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, China Academy of Sciences, Beijing 100085, China