1. Zhejiang Provincial Key Lab. of Agricultural Resources and Environment College of Environmental and Resource Sciences Zhejiang Univ. Hangzhou 310058 China
2. Institute of Environment Resource and Soil Fertilizer Zhejiang Academy of Agricultural Sciences Hangzhou 310021 China
3. State Key Lab. of Eco‐hydraulics in Northwest Arid Region of China Xi'an Univ. of Technology Xi'an 710048 China
4. Agricultural Experiment Station Zhejiang Univ. Hangzhou 310058 China