1. State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
2. University of Chinese Academy of Sciences, Beijing 100049, China
3. Air Quality Research Division, Science and Technology Branch, Environment and Climate Change Canada, Toronto M3H5T4, Canada
4. School of Resources and Environment, Zunyi Normal College, Zunyi 563006, China
5. CAS Center for Excellence in Quaternary Science and Global Change, Xi’an 710061, China