1. State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China
2. Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
3. Department of Soil Science of Temperate Ecosystems, University of Göttingen, 37077 Göttingen, Germany
4. Agro-Technological Institute, Peoples Friendship University of Russia (RUDN University), 117198 Moscow, Russia
5. Institute of Environmental Sciences, Kazan Federal University, 420049 Kazan, Russia
6. China Land Surveying and Planning Institute, Beijing 100035, China
7. College of Land Science and Technology, China Agricultural University, Beijing 100193, China
8. School of Land Science and Technology, China University of Geosciences, Beijing 100083, China