“…In addition to describing soil variability, scaling has facilitated a parallel avenue helping to formulate unsaturated flow and transport in similar soils in a universal, scale‐invariant or soil‐independent manner [ Reichardt et al ., ; Warrick and Amoozegar‐Fard , ; Sharma et al ., ; Youngs and Price , ; Warrick et al ., ; Sposito and Jury , ; Kutilek et al ., ; Warrick and Hussen , ; Nachabe , ; Wu and Pan , ; Shukla et al ., ; Rasoulzadeh and Sepaskhah , ; Kozak and Ahuja , ; Roth , ; Sadeghi et al ., ; Sadeghi and Jones , ]. Referring to macro Miller, Nielsen, and Warrick‐type similitude, Sposito [] examined invariance of the Richards' equation with Lie group analysis leading to power‐law or exponential soil hydraulic functions [ Warrick , , p. 46].…”