[1] Changan Univ, Sch Water & Environm, 126 Yanta Rd, Xian 710054, Shaanxi, Peoples R China
[2] Changan Univ, Key Lab Subsurface Hydrol & Ecol Effects Arid Reg, Minist Educ, 126 Yanta Rd, Xian 710054, Shaanxi, Peoples R China
[3] Hebei GEO Univ, Sch Water Resources & Environm, Shijiazhuang 050031, Hebei, Peoples R China
[4] Univ Zululand, Dept Hydrol, ZA-3886 Durban, South Africa