Eriksson_1997_height_trajectory_Sweden_Birch: Height trajectory for Birch in Sweden from Eriksson et al...

In Silviculturalist/forester: Forest Science and Forestry

Height trajectory for Birch in Sweden from Eriksson et al 1997.

Description

Abstract

A site‐index model was constructed based on stem analysis data for 266 top‐height trees of Betula pendula Roth and Betula pubescens Ehrh. growing on 155 temporary sample plots and 12 remeasured, permanent sample plots in pure and mixed stands scattered throughout Sweden. Different growth functions and techniques for modelling the top‐height growth over breast‐height age were assessed. A difference model based on the Hossfeld IV growth equation performed best, and its practical application was therefore recommended. For birch stands over 40 yrs of age, top‐height growth predicted by the new model was significantly slower than that predicted by a site‐index model used previously.

Usage

Eriksson_1997_height_trajectory_Sweden_Birch(
  dominant_height,
  age,
  age2,
  output = "Height"
)

Arguments

dominant_height	Dominant height of stand, m.
age	Age at breast height.
age2	Output age at breast height.
output	One of "SIH100","Equation" or "Height".

Value

One of output.

Source

Eriksson, H., Johansson, U., Kiviste, A. (1997) A site-index model for pure and mixed stands of Betula pendula and Betula pubescens in Sweden. Scandinavian Journal of Forest Research. 12:2, 149-156. Available: https://doi.org/10.1080/02827589709355396

Examples

ErikssonVect <- Vectorize(Eriksson_1997_height_trajectory_Sweden_Birch)

plot(NULL,
    xlim=c(0,100),
    ylim=c(0,35))

for(i in 1:11){
 lines(seq(0,100,0.1),ErikssonVect(seq(10,30,2)[i],age = 50,age2 = seq(0,100,0.1)))
}

points(rep(50,11),seq(10,30,2))

Silviculturalist/forester documentation built on April 20, 2024, 2:13 p.m.