1. Key Lab. of Agricultural Soil and Water Engineering in Arid Area of Ministry of EducationNorthwest Agriculture and Forestry Univ.Yangling712100China
2. School of Water ConservancyNorth China Univ. of Water Resources and Electric PowerZhengzhou450046China
3. Dep. of Soil and Physical Sciences, Faculty of Agriculture and Life ScienceLincoln Univ.LincolnCanterbury7647New Zealand
4. USDA‐ARS, National Lab. of Agriculture and the Environment (NLAE)AmesIA50011