1. MOE Key Laboratory of Western China’s Environmental Systems, College of Earth & Environmental Sciences, Lanzhou University, Lanzhou, Gansu Province, China
2. Gansu Provincial Institute of Cultural Relics and Archaeology, Lanzhou, Gansu Province, China
3. Department of Anthropology, Washington University in St Louis, St Louis, MO, USA
4. School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW, Australia
5. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, CAS, Xi’an, Shaanxi Province, China