When modeling soil h
ydraulic properties at field scale it is desirable to approximate the variabilit
y in a given area b
y means of some scaling transformations which relate spatiall
y variable local h
ydraulic properties to global reference characteristics. Sevent
y soil cores were sampled within a drip irrigated banana plantation greenhouse on a 14×5 arra
y of 2.5 m×5 m rectangles at 15 cm depth, to represent the field scale variabilit
y of flow related properties. Saturated h
ydraulic conductivit
y and water retention characteristics were measured in these 70 soil cores. van Genuchten water retention curves (WRC) with optimized
m (
m≠1−1/
n) were fitted to the WR data and a general
Mualem-van Genuchten model was used to predict h
ydraulic conductivit
y functions for each soil core. A scaling law, of the form
![]()
, was fitted to soil h
ydraulic data, such that the original h
ydraulic parameters
νi were scaled down to a reference curve with parameters
![]()
. An anal
ytical expression, in terms of Beta functions, for the average suction value,
hc, necessar
y to appl
y the above scaling method, was obtained. A robust optimization procedure with fast convergence to the global minimum is used to find the optimum
hc, such that dispersion is minimized in the scaled data set. Via the Box–Cox transformation
![]()
, Box–Cox normalit
y plots showed that scaling factors for the suction (
αh) and h
ydraulic conductivit
y (
αk) were approximatel
y log-normall
y distributed (i.e.
τ