hemc: High-Energy-Moisture-Characteristics Aggregate Stability

In arsilva87/soilphysics: Soil Physical Analysis

High-Energy-Moisture-Characteristics Aggregate Stability

Description

A function to determine the modal suction, volume of drainable pores, structural index and stability ratio using the high-energy-moisture-characteristics (HEMC) method by Pierson & Mulla (1989), which is used to analyze the aggregate stability. Before using hemc(), the user may estimate the parameters of the Modified van Genuchten's Model through the function fitsoilwater5().

Usage

hemc(x, theta_R, theta_S, alpha, n, b1, b2, 
	graph = TRUE, from = 1, to = 30, 
	xlab = expression(Psi ~ (J~kg^{-1})), 
	ylab = expression(d ~ theta/d ~ Psi), ...)

Arguments

x	a vector containing matric potential values.
theta_R	a numeric vector of length two containing the parameter values in the following orde: fast and slow.
theta_S	a numeric vector of length two containing the parameter values in the following orde: fast and slow.
alpha	a numeric vector of length two containing the parameter values in the following orde: fast and slow.
n	a numeric vector of length two containing the parameter values in the following orde: fast and slow.
b1	a numeric vector of length two containing the parameter values in the following orde: fast and slow.
b2	a numeric vector of length two containing the parameter values in the following orde: fast and slow.
graph	logical; if TRUE (default), a graphical solution is shown).
from	the lower limit for the x-axis
to	the lower limit for the x-axis
xlab	a label for the x-axis
ylab	a label for the y-axis
...	further graphical arguments

Value

A list of a two objects: 1) a matrix containing the Modal Suction, the Volume od Drainable Pores (VDP) and the Structural Index for both, fast and slow wetting; and 2) the value of Stability Ratio.

Author(s)

Anderson Rodrigo da Silva <[e-mail]>

References

Pierson, F.B.; Mulla, D.J. (1989). An Improved Method for Measuring Aggregate Stability of a Weakly Aggregated Loessial Soil. Soil Sci. Soc. Am. J., 53:1825–1831.

See Also

fitsoilwater5

Examples

hemc(x = seq(1, 30), theta_R = c(0.27, 0.4), theta_S = c(0.65, 0.47), 
	alpha = c(0.1393, 0.0954), n = c(6.37, 7.47), 
	b1 = c(-0.008421, -0.011970), b2 = c(0.0001322, 0.0001552))

# End (Not run)

arsilva87/soilphysics documentation built on July 30, 2022, 8:46 p.m.