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 fe_species_ger_nfi_2012 object. See Details for how other species codings are handled.

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)


[Package ForestElementsR version 2.1.0 Index]