standing_area_gnfi3 {ForestElementsR} | R Documentation |
Estimate the Standing Area of Single Trees
Description
An implementation of the standing area estimation of the third German National Forest Inventory (Riedel et al. 2017). Its main intended use is the calculation of virtual species areas in mixed stands. According to (Riedel et al. 2017), it is recommended only to include the main stand in such calculations, neither understorey, nor any layers above the main stand.
Usage
standing_area_gnfi3(species_id, dbh_cm)
Arguments
species_id |
Vector of species id's preferably following the
ger_nfi_2012 species coding. Ideally, these species_id's are provided as
a |
dbh_cm |
Vector of tree dbh values in cm (dbh = stem diameter at breast height, i.e. 1.3 m) |
Details
Originally, the function was parameterized for species and species groups
corresponding to the national forest inventory's species coding
(fe_species_ger_nfi_2012
). We have attributed in addition these
the original parameters also to the species codings
fe_species_tum_wwk_short
, and
fe_species_bavrn_state_short
. When called with a given species
coding, the function will try to use the "nearest" of these three
alternatives. Fallback option is the attempt to use
fe_species_tum_wwk_short
.
Value
A vector of the estimated standing areas in m²
Examples
# Three spruces, two pines, two beech
species_id <- fe_species_ger_nfi_2012(c(10, 10, 10, 20, 20, 100, 100))
dbh_cm <- c(10.1, 27.4, 31.4, 35.5, 39.8, 45.2, 47.2)
standing_area_gnfi3(species_id, dbh_cm)