VPRODmodule: Calculates tree volume (inside bark) based on taper equations...

In sgezan/Nothopack: G&Y Forest Simulator for Roble-Rauli-Coigue Stands in Chile

Description

Individual tree volume for different products, according to a table of product specifications, is calculated over all individuals provided in a tree list (based on DBH, HT, SPECIES). A new tree list with additional columns is generated, which can be used to obtain a stand table. Note: the table of product specificiacionts needs to be ordered from most to least important.

Usage

VPRODmodule(
  tree.list = NA,
  ZONE = NA,
  prod.list = NA,
  T_model = 2,
  stump = 0.3
)

Arguments

tree.list	Data frame containing the following vectors: ID (tree id), SPECIES (tree specie), DBH (diameter breast height, cm), HT (total tree height, m). Additional columns can be included but these will be ignored
ZONE	Growth zone of the corresponding stand
prod.list	Data frame containing the following vectors: Product (product abbreviation), Desc (description of product), Dmin (minimum diameter for product, cm), Length (length of section, m)
T_model	Model selected for taper equation (1:zone specific, 2:all zones) (default = 2)
stump	Length of stump to discount (default = 0.3 m)

Value

Updated tree list with additional columns of individual tree volume products (m3) (one column per product)

Author(s)

S.A. Gezan

References

Gezan, S.A. and Moreno, P. (2000b). Informe Modelos de Volumen. Reporte Interno. Projecto FONDEF D97I1065. Chile

Examples

# Example: Calculation of volumes for 5 different products with their stand table
tree.data <- plot_example
head(tree.data,10)  # Original data
tree.inv <- input_module(ZONE=1, AD=28, type='tree', area=500, tree.list=tree.data, T_model=2)
head(tree.inv$tree.list, 10)
Product <- c('SL', 'SS', 'PP', 'IF', 'RES')
Desc <- c('Saw-log (large)','Saw-log (short)','Panel','Industrial Firewood','Residual')
Dmin <- c(18, 16, 10, 5, 0)
Length <- c(4.1, 3.2, 2.44, 1.22, 99)
(Vprod <- data.frame(Product,Desc,Dmin,Length))
updated.tree.list <- VPRODmodule(tree.list=tree.inv$tree.list, ZONE=tree.inv$ZONE,
                               prod.list=Vprod, T_model=2)
head(updated.tree.list, 10)
tree.inv$sp.table
plot.extra <- stand_parameters(plotdata=updated.tree.list, area=500,
                  extra=c(8,9,10,11,12,13,14))
plot.extra$sd

sgezan/Nothopack documentation built on April 25, 2021, 8:03 a.m.