1. College of Water Resources and Architectural EngineeringNorthwest A&F Univ.YanglingShaanxi712100China
2. Key Lab. for Agricultural Soil and Water Engineering in Arid Area, Ministry of EducationNorthwest A&F Univ.YanglingShaanxi712100China
3. Univ. of Florida, Institute for Sustainable Food SystemsGainesvilleFL32611
4. Institute of Water Saving Agriculture in Arid Areas of ChinaNorthwest A&F Univ.YanglingShaanxi712100China
5. AgWeatherNet ProgramWashington State Univ.ProsserWA99350‐8694