Vegetation Class Reference

Holds the vegetation parameters for the calculation of ET and fractionating rainfall. Not every ET method uses all parameters. More...

Detailed Description

Holds the vegetation parameters for the calculation of ET and fractionating rainfall. Not every ET method uses all parameters.

Public Member Functions
double	RootFraction (double upperBoundary, double lowerBoundary) const
	Returns the fraction of root mass in a segment of the soil column per total root mass.
double	RootLength () const
	Returns the average root length in m/m2.

Public Attributes
double	albedo
	Fraction of reflected radiation.
double	CanopyCapacityPerLAI
	Capacity of interception storage per LAI unit in mm.
double	CanopyClosure
	Fraction of bare soil to the surface, influences the routing of rainfall.
double	CanopyPARExtinction
	extinction coefficient for photosynthetically-active radiation in the canopy. Values usually range from 0.5 to 0.7. Values outside this range should be used very cautiously.
double	fraction_at_rootdepth
	Fraction of roots in the rooting zone. If 1 (default), a uniform root distribution is used, otherwise an exponential decay of the root density with depth is used.
double	Height
	Height of the vegetation in m.
double	LAI
	Leaf area index.
double	LeafWidth
	Average width of leaves in m (only for Shuttleworth-Wallace ET)
double	RootContent
	average fine root content in kg/m3 (default 2 kg/m3) in root depth.
double	RootDepth
	Depth of rooting zone in m, see fraction_at_rootdepth. Only used if root_distribution and root_distribution_depth are not set.
double	snow_albedo
	Fraction of reflected radiation at snow cover.
double	StomatalResistance
	optimal stomatal resistence of the plant tissue for vapor, in s/m

Member Function Documentation

RootFraction()

double RootFraction	(	double	upperBoundary,
		double	lowerBoundary ) const

Returns the fraction of root mass in a segment of the soil column per total root mass.

Parameters

upperBoundary,lowerBoundary

Upper and lower depth below ground of the segment The method to claculate the distribution of roots in the soil depends on the fraction_at_rootdepth \(f_{r0}\) parameter. If \(f_{r0}=1\), a uniform distribution from the ground to the root depth is assumed. If \(f_{r0}<1\), an exponential decline of root density with depth is assumed, that \(f_{r0}\) of the roots are above the root depth r0. \[f_{r}(z_u,z_l) = (\frac 1 {1-f_{r0}})^{z_l-r0} - (\frac 1 {1-f_{r0}})^{z_u-r0}\]