1. School of Water and Environment, Chang’an University, Xi’an 710054, China
2. Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region, Ministry of Education, Chang’an University, Xi’an 710054, China
3. College of Water Resources and Architectural Engineering, Northwest A&F University, Xianyang 712100, China
4. Department of Earth and Environmental Sciences, California State University, Fresno, CA 93740, USA