DIGITALNA ARHIVA ŠUMARSKOG LISTA
prilagođeno pretraživanje po punom tekstu




ŠUMARSKI LIST 7-8/2006 str. 38     <-- 38 -->        PDF

M. Prka: ZNAČAJKE DOZNAČENIH BUKOVIH STABALA PO VRSTI SIJEKA U SJEĆINAMA ...
SUMMARY: The subject of research were absolute and percentage share
of assigned trees according to diameter class and type of felling and their influence
on assortment structure of particular types offelling. The assigned
exemplary trees were categorized according to the most prominent outward
features into nine categories. The research was carried out on the total number
of 36 areas of the economic unit Bjelovarska Bilogora. In the seeding felling
areas data were collected on several occasions (felling). In that way,
2,308 assigned trees were categorized in the total of 46 occasions (felling).
All the areas belong to ecological-economical type II-D-11 and structural
class BEECH with the rotation of 100 years.


The aim of the process was gaining more insight into the factors that influence
assortment structure of stands, as well as completing the information
on principles and ways of forest management in the past and nowadays. Analysis
of the number of trees of particular categories according to the type of
felling (stand age) and diameter class was carried out with the aim of finding
the answers to questions pertaining to the criteria of assignment of one type
offelling, as well as the degree of damage to stands during the exploiting of
forest in the area subject to research.


The assigned trees of group A (undamaged trees of normal growth) have,
on the whole, extremely positive influence on assortment structure of particular
type offelling. To these we can, to a certain extent, join pregrowth trees,


i.e. group G, whose influence is limited mostly to thinningfelling. Trees of all
the other described groups have more or less negative effect on assortment
structure of particular type of felling. The influence of suppressed trees
(group H) on assortment structure is insignificant, and their importance for
successful carrying out of seedingfelling is considerable.
Thepercentage of trees with positive influence on assortment structure according
to the type offelling, stands about 50 % in thinning and preparatory
felling, while in seeding andfinal felling it is about 60 %.


Trees of medium diameter and large diameter, i.e. trees of diameter class
between 41 cm and 60 cm, and those with breast diameter over 61 cm, have
the greatest influence on the whole of tree assortment structure or particular
types of felling. The reasonfor that is thefact that only those trees can potentially
contain timber assortment of the highest quality (according to Croatian
Standards of Forest Exploitation Productsfrom 1995) because of the minimal
dimensions prescribed for timber assortments of the highest quality. Percentage
of those trees with positive and negative influence on assortment structure
is almost identical in case of thinning andpreparatory felling, while in case
of seeding andfinalfelling the share of trees with positive effect is considerably
higher than the percentage of trees with negative effect on assortment
structure.


It can be said that the percentage of trees with breast diameter larger than
41 cm, with the positive effect on assortment structure grows from 5.7 % in
thinningfelling to 57.5 % infinalfelling. If wefocus on the relation (difference)
between the trees with breast diameter larger than 41 cm, with positive
and negative effect on assortment structure, we can easily say that this value
rangesfrom -2.9 % in thinningfelling to 22.9 % in final felling.


Trees damaged as a result of our activities, or human influence, are contained
within groups with description marks of C, D, E and I. The percentage
of trees damaged by human activity increases from thinning felling to final


felling. For thinning felling, this percentage amounts to 11.2 %, for preparatory
felling it is 13.1 %, for seeding felling it is 15.8 %, while for final felling
it amount % damage The increase in participation of trees


ts
ss t
tto
oo 23.
23.23.3
33 o
oof
ff da aged
dd trees
treestrees.
.. T
it


damaged in
nn tha
thathat wa
waway
yy toward
towardtowards
ss th
ththe
ee en
enend
dd o
oof
ff rotation can be attributed to intensi


Šumarski list br. 7-8, CXXX (2006), 319-329