1. Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtse River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
2. Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering, Nanjing University, Nanjing, Jiangsu 210023, China
3. State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, Guizhou 550002, China
4. School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK
5. Department of Crop and Soil Sciences, North Carolina State University, Raleigh, North Carolina 27695, United States
6. Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100039, China
7. College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot 010018, China