dbhDiff: DBH differentiation - Pommerening 2002

In johngodlee/compInd: Forest tree-tree competition indices

DBH differentiation - Pommerening 2002

Description

DBH differentiation - Pommerening 2002

Usage

dbhDiff(dbh, focal_dbh)

Arguments

dbh	vector of dbh (diameter at breast height) measurements of competitor trees
focal_dbh	dbh of focal tree

Details

Gives the size difference of neighbouring trees and describes the spatial distribution of tree sizes. The value increases with increasing average size difference between neighbouring trees. dbhDiff == 0 when all neighbours have equal size.

Value

value of competition index for focal tree

References

Pommerening, A. (2002). Approaches to quantifying forest structures. Forestry, Volume 75, Issue 3. Pages 305-324.

Examples

data(bicuar)
nb <- nearNeighb(bicuar$x, bicuar$y, bicuar$stem_id, k = 4) 
lapply(nb, function(x) {
  nb <- merge(x, bicuar, by.x = "nb", by.y = "stem_id")
  focal_diam <- unique(bicuar[bicuar$stem_id == nb$focal,"diam"])
  dbhDiff(nb$diam, focal_diam)
  })

johngodlee/compInd documentation built on Aug. 5, 2024, 8:44 a.m.