1. College of Land and Environment; Shenyang Agricultural University; Shenyang China
2. Key Laboratory of Arable Land Conservation (Northeast China); Ministry of Agriculture; Shenyang China
3. National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources; Shenyang China
4. Department of Crop & Soil Sciences; Washington State University; Pullman WA
5. Department of Crop & Soil Sciences; Washington State University; Puyallup WA