1. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
2. Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-90183 Umeå, Sweden
3. CAS Center for Excellence in Quaternary Science and Global Change, Xi’an 710061, China
4. University of Chinese Academy of Sciences, Beijing 100049, China