1. College of Natural Resources & Environment, Northwest A&F University, Yangling, China
2. Key Laboratory of Crop Nutrition and Fertilization, Ministry of Agriculture of China, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
3. Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
4. Department of Horticulture, The University of Agriculture, Peshawar, Pakistan
5. Department of Environmental Science and Technology, University of Maryland, College Park, MD, USA