Original scientific paper

MODELLING OF STANDING BEECH TREES ASSORTMENT STRUCTURE

Elvis Paladinić orcid.org/0000-0003-4886-4476 ; Forest Research Institute, Jastrebarsko
Dijana Vuletić orcid.org/0000-0003-4631-7604 ; Forest Research Institute, Jastrebarsko

Abstract

The paper presents a way to determine a proposal for improving existing models for
evaluation of timber assortments, which are used by forestry operative units. The incentive
for the investigation of this theme were the frequent reports from forestry operative units on
inconsistency of the planned values of assortments with the values of assortments realised
in the process of production (according to the amount and quality of the assortment structure).
The paper examines the mutual relations of the planned amounts of timber assortments
(according to Hs-PPI programme) and the estimated volume of assortments on the
part of the estimator from Forest Research Institute, and the forestry employees, on samples
from five investigated localities. The localities investigated covered four forestry communities,
three different ecological-managerial forest types (EMFT) and 5 age class. In thinnings
on all five localities an assortment method during logging was utilised.
On the basis of the obtained results which indicate significant correlations between the
volume of certain assortment classes, conditions were formed for exclusion of "unreal zeros"
from the sample data prior to regression analyses of the volume of assortment classes. By
analysis of variance of three variables "locality", "method of evaluation" and "interaction locality
* method of evaluation" it was established that "locality" is the most influential variable
on the variability of the volume of assortment classes.
Of the tested mathematical models, model called "VD1" (VONDRA 1991) most reliably
described the development of the volume of different assortment classes. On the basis
of the results of the research, improvements in the existing models of evaluation of timber
assortments were proposed, with regard to new model coefficients. Additional more investigations
are necessary for more precise and reliable results of evaluation of the volume of assortments
at the level of locality (stand/group of trees).

Keywords

beech; evaluation model; assortment structure; intermediate income

Hrčak ID:

26030

URI

https://hrcak.srce.hr/26030

Publication date:

24.9.2006.

Article data in other languages: croatian

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