flim: Forest Light Interaction Model (FLIM)

In MarcoDVisser/ccrtm: Coupled Chain Radiative Transfer Models

Forest Light Interaction Model (FLIM)

Description

The FLIM model was first described by Rosema et al (1992). In FLIM forests are assumed a discontinous mix of tree crowns and gaps. Reflectance is modelled in terms of the probabilty to observe either a gap (background) or a tree crown. Both gaps and crowns may be shaded.

Usage

flim(Rc, Rg, To = NULL, Ts = NULL, params)

Arguments

Rc	Canopy reflectance at infinite depth
Rg	soil/background reflectance
To	transmission in viewing direction
Ts	transmission in sun direction
params	a named vector of parameters: 1 = stand density (d) (1) 2 = crown diameter (cd) (1) 3 = mean crown height (h) 4 = leaf area index (lai) (2) 5 = light extinction coefficient (alpha) (2) 6 = Solar zenith angle (tts) 7 = Observer zenith angle (tto) 8 = Sun-sensor azimuth angle (psi)
area	area of stand (m2)

Details

(1) Parameters are confounded (d & cd), confounded parameters pairs cannot be inversely estimated, one of the pairs should be set to 1 - or given explicitly. (2) required if T0, Ts are not given.

Value

a list with reflectance, and the fractions of shaded and sunexplosed crowns, shaded and sun exposed open space.

References

Rosema, A., Verhoef, W., Noorbergen, H., Borgesius, J.J. (1992). A new forest light interaction model in support of forest monitoring. Remote Sens. Environ. 42, 23-41.

Examples

parvec<- c(alpha = 0.5,lai=5,cd=15,h=30,d=10,tto=10,tts=20,psi=30)
flim(0.1,0.1,params=parvec)
   

MarcoDVisser/ccrtm documentation built on Feb. 19, 2025, 1:15 p.m.