| ptf.vG2BW {spsh} | R Documentation |
Parameter Transfer Function for Weber et al.(2019) model.
Description
Predicts (Weber et al. 2019) model parameters in the van Genuchten-Mualem variant 01110FM, from given van Genuchten-Mualem parameters for the constrained van Genuchten-Mualem model.
Usage
ptf.vG2BW(x)
Arguments
x |
vector of 6 van Genuchten-Model parameters. The order is sensitive see for
|
Details
Pedotransfer function returns the van Genuchten - Mualem model shypFun.01110 parameters in the Brunswick-Model variant 01110FM, based on previously determined van Genuchten-Mualem parameters. The transfer function is based on an ordinary linear regression between the i-th 01110 and 01110FM. The paraemeters
were based on model parameter estimation to a dataset of >400 samples with retention and conductivity measurements.
Value
thsnc | Saturated water content of the non-capillary part. |
thsc | Saturated water content of the capillary part. |
alf | Shape parameter (cm^-1) |
n | Shape parameter (-) |
Ksc | Saturated hydraulic conductivity of the capillary part [cm day-1] |
tau | Shape parameter (-) |
Ksnc | Saturated hydraulic conductivity of the non-capillary part [cm day-1] |
a | slope of the non-capillary unsaturated conductivity [ - ] |
h0 | anker point at which the water content is 0 |
Note
The parameter transfer function was derived by weighted linear regression with weights in x and y,
by regressing the estimated the Brunswick model parameters in the Genuchten Mualem variant (Weber et al. 2019)
inferred from matching measured soil water retention and hydraulic conductivity data against the constrained van Genuchten model parameters.
The regression of alf1 and Ks, and (n-1) was done in the log[10])-transformed space,
and Kncs is a fixed value of 10^-1.72.
Author(s)
Efstathios Diamantopoulos , ed@plen.ku.dk
Tobias KD Weber , tobias.weber@uni-hohenheim.de
See Also
Examples
p <- c(0.08, 0.42, 0.01, 1.5, 100, 0.5)
result <- ptf.vG2BW(p)