Variable:SiteIndexH (SIH)

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Name: SiteIndexH (SIH)
Description: SiteIndexH (SIH)
I/O: Output variable (prognosis)
Membership: Treatment unit
Type: real
Unit/values: (m)
Database table: dbo.Result_ForestData


Usage

Variable SiteIndexH (SIH) is a computed value for H100, i.e. dominant height at an "imagined" age of 100 years. SiteIndexH is only used for presentation purposes and is not used as explanatory variable in any function. To be computed, it requires that the [[Variable:Dominant_Species|dominant species}} proportion is at least 70 % of the basal area.

Definition

SiteIndexH is derived from site index equations. The site index equations gives the height h at age a, given initial height h0 at age a0. For young stands and SiteIndexH could be higher that SIS (site index determined from site factors) (cf. [1]). SiteIndexH is computed as the arithmetic mean height of dominant trees when each of these tree is 100 years old (50 years for birch). For dominant trees younger than 100 years, SiteIndexH should be lesser than current dominant Height. For dominant trees 100 years old, dominant height and SiteIndeH should be about the same. For dominant trees older than 100 years, SiteIndexH should be smaller than current dominant height.


References

  1. Elfving B och Nyström K, 1996. Yield Capacity of planted Picea abies in Northern Sweden, Scandinavien Journal of Forest Research 11:38-49.