1. College of Urban and Rural Construction, Shanxi Agricultural University, Taigu, Shanxi, China
2. Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education, Northwest A&F University, Yangling, Shaanxi, China
3. China Meteorological Administration, Institute of Arid Meteorology, Lanzhou, Gansu, China
4. College of Agriculture, Shanxi Agricultural University, Taigu, Shanxi, China