1. College of Natural Resources and Environment Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of Agriculture, Northwest A&F University Yangling China
2. College of Resources and Environmental Sciences Key Laboratory of Plant‐Soil Interactions Ministry of Education China Agricultural University Beijing China
3. Department of Agricultural Soil Science Department of Soil Science of Temperate Ecosystems Georg‐August University of Göttingen Göttingen Germany