fitsoilwater3 {soilphysics}

Interactive Estimation of the Dexter's (2008) Model Parameters

Description

An interactive graphical adjustment of the soil water retention curve through the Dexter's (2008) formula. The nonlinear least-squares estimates can be achieved taking the graphical initial values.

Usage

fitsoilwater3(theta, x, xlab = NULL, ylab = NULL, ...)

Arguments

theta

a numeric vector containing the values of soil water content.

x

a numeric vector containing the values of applied air pressure.

xlab

a label for the x axis; if is NULL, the label "pF" is used.

ylab

a label for the y axis; if is NULL, the label "Soil water content" is used.

...

further graphical arguments; see par.

Value

A plot of theta versus x and the curve of the current fitted model according to the adjusted parameters in an external interactive panel. Pressing the button "NLS estimates" a nls summary of the fitted model is printed on console whether convergence is achieved, otherwise a warning box of "No convergence" is shown.

Author(s)

Anderson Rodrigo da Silva <[e-mail]>

References

Dexter et al. (2008). A user-friendly water retention function that takes account of the textural and structural pore spaces in soil. Geoderma, 143:243–253.

See Also

soilwater3, nls, fitsoilwater2

Examples

# data extracted from Liu et al. (2011)
h <- c(0.001, 50.65, 293.77, 790.14, 992.74, 5065, 10130, 15195)
w <- c(0.5650, 0.4013, 0.2502, 0.2324, 0.2307, 0.1926, 0.1812, 0.1730)
fitsoilwater3(w, h)

# End (not run)