1. Department of Urban and
Environmental Sciences and
Key Laboratory for Earth Surface Processes
Ministry of Education
Peking University
Beijing 100871, China
2. Ministry of Natural Resources
Ontario Forest Research Institute
1235 Queen Street East
Sault Ste. Marie, Ontario P6A 2E5, Canada
3. Department of Geosciences
University of Missouri, Kansas City
5100 Rockhill Road
Kansas City, MO 64110–2499, USA