rfTreeDensity: Tree density at forest level, based on a relascopic plot
In mbask/forestry: Tools for common forestry related analyses

Description Usage Arguments Details Value Note Author(s) See Also Examples

Tree density is estimated as N=φ \cdot ∑_{i=1}^{n_φ}{\frac{1}{g_i}} where φ is the relascopic band used during sampling, n_φ is the total count of trees found to be inside of a relascopic plot measured with the φ band.

1 2	rfTreeDensity(treeG, treeCount = 1, relascopeBand = 2, unit = "auto")

`treeG`	a single tree diameter or vector of tree diameters in cm
`treeCount`	whether a tree is inside the plot (1, default value), at its edge (0.5), or outside (0)
`relascopeBand`	the relascopic band used in the relascopic plot (1, 2, 4), default: 2
`unit`	a character value to indicate the unit of measure of `treeDbh`: `cm2`, `m2`, `auto` (default value)

The function guesses the unit of measure of tree basal area (cm^2 or m^2) if parameter unit is set to "auto":

cm^2 one or more trees have basal area higher than 18.09557 (i.e. tree dbh > 2.4)
m^2 all trees have basal area lower or equal than 18.09557 (i.e. tree dbh ≤q 2.4) Therefore, should trees larger than 2.4 m be measured the unit parameter should be explicitly set to either cm2 or m2.

a single numeric value (estimate of count of trees per hectare), not rounded

The 2.4 dbh threshold has been chosen as it is the most used lower limit for dbh, in cm, in tree measurements. Therefore if a tree dbh is ≤q 2.4 than its unit of measurement is m, otherwise it may be either cm and m, the functions assumes it is cm.

Marco Bascietto marco.bascietto@ibaf.cnr.it

Other structuralAnalysis: pfExpand, rfBasalArea, tpBasalArea, ttBasalArea, ttMeanDbh

# dbh from an ideal even-aged plot, in cm
dbhList <- runif(10, min = 30, max = 40)
# Basal area of trees
g <- ttBasalArea(dbhList)
rfTreeDensity(g)
rfTreeDensity(g/1e4)