Pettersson_1992_volume_distribution_after_PCT_Spruce: Mean of Volume distribution for stands after PCT of Norway...

In Silviculturalist/forester: Forest Science and Forestry

Mean of Volume distribution for stands after PCT of Norway Spruce from Pettersson 1992

Description

Mean of Volume distribution for stands after PCT of Norway Spruce from Pettersson 1992

Usage

Pettersson_1992_volume_distribution_after_PCT_Spruce(
  diameter_mean_basal_area_stem,
  stems,
  dominant_height,
  SI
)

Arguments

diameter_mean_basal_area_stem	Diameter corresponding the mean basal area stem, cm.
stems	Stems per hectare
dominant_height	Dominant height, metres.
SI	Site Index, m, according to Hägglund 1972, 1973 [forester::Hagglund_1972_northern_Sweden_Height_trajectories_Spruce],[forester::Hagglund_1973_southern_Sweden_Height_trajectories_Spruce]

Value

Volume distribution for stands of Norway Spruce after PCT

Source

Pettersson Nils (1992) The effect on stand development of different spacing after planting and precommercial thinning in Norway Spruce (Picea abies (L.) Karst.) and Scots Pine (Pinus sylvestris L.) stands: The effect of density after precommercial thinning on volume and structure in Pinus sylvestris and Picea abies stands. Diss. Report no. 34, Dept. of Forest Yield Research. ISSN 0348-7636. p. 9.

@description

"A Gram-Charlier-series (Kendall et al. 1987), was used by Eriksson (1976) for the description of the frequency of stems and volume by diameter classes and by Pettersson (1992) for the description of the volume distribution by diameter classes. For the application on the distributions in my material the function has the following form:

y = \frac{V}{\sigma} [ \varphi (\frac{x-m}{\sigma}) - \frac{\lambda_1}{6}\varphi^3(\frac{x-m}{\sigma})+\frac{\lambda_2}{24}\varphi^4(\frac{x-m}{\sigma})+\frac{\lambda_1^2}{720}\varphi^6(\frac{x-m}{\sigma} ]

where \varphi = the normal frequency distribution, \varphi^{v}= the v:th derivate of \varphi, \lambda_{1} = the skewness of the distribution, \lambda_{2}=the kurtosis of the distribution, V= total volume in the distribution, y=frequency of volume for the actual class, x= middle of the class, m=mean of the distribution, and \sigma = standard deviation of the distribution."

@details

Mean : F= 1426 R^2 = 0.94

Standard deviation: F=45 R^2 = 0.49

Skew + 3 F= 7 R^2 = 0.16

Kurtosis + 3 F = 5 R^2 = 0.10

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