growth_summary: Calculate annual growth

In sgraham9319/ForestPlotR: Tree growth as a function of its neighbors

Calculate annual growth

Description

Requires a data frame where separate measurements of the same tree appear in different rows and returns a data frame with a single row for each tree containing annual growth measurements.

Usage

growth_summary(data)

Arguments

data	A dataframe containing repeated measurements of growth. Must have a column named "tree_id" that contains unique tree ID values, a column named "year" containing the year of the measurement, and a column named "dbh" containing the dbh measurements.See built-in dataset tree for an example.

Value

A dataframe containing growth rate measurements for each tree:

tree_id

unique identification code of the tree

stand_id

name of stand in which tree is located - only appears if input dataframe contains a stand_id column

species

species identity of tree as a four letter code

first_record

year of first size measurement of the tree

last_record

year of last size measurement of the tree

begin_size

first size measurement as diameter at breast height, in cm

final_size

last size measurement as diameter at breast height, in cm

mean_size

average size across measurements as diameter at breast height, in cm

midpoint_size

average of maximum and minimum size across measurements as diameter at breast height, in cm

annual_growth

annual growth rate as average yearly increase in diameter at breast height, in cm/year

annual_bai

annual basal area increment as average yearly increase in area at breast height, in cm^2/year

size_corr_growth

square root of annual_growth divided by begin_size to give somewhat normally distributed growth rates

size_corr_growth_basal

square root of annual_bai divided by begin_size to give somewhat normally distributed growth rates

Examples

growth_summary(tree)

sgraham9319/ForestPlotR documentation built on April 15, 2022, 4:01 p.m.