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ŠUMARSKI LIST 9-10/2011 str. 24     <-- 24 -->        PDF

V. Račko, M. Saniga, I. Čunderlík: THE IMPACT OF SILVICULTURALTREATMENTS ON THE STRUCTURE ...Šumarski list br. 9–10, CXXXV (2011), 437-448
cennt to vessels) react to the embolism by plugging the
vessels with tyloses (Zycha1948,Necesany1958,
BonsenandKucera1990). Simultaneously,oxidativereactionstranstormthe
starchandsolublecarbohydrates
inlivingcellsintocolouredphenol substances.
Subsequently,colouredphenol compoundsform parenchyma
cells aredepositedinthe surroundingxylem
(Bauchand Koch2001). RHformationwill terminatewhenthewound
isclosed.An important factor in
this process is the closure rate of injuries to new growth
rings of wound wood (ShigoandLarson1969).


The RH formation (frequency and size) froma ma cros
copicviewis significantlyinfluenced by theage,
diameter at breast height(DBH)of stem (Knokeand
Wenderoth2001,KremplandMark1962,Mahler
andHöwecke1991,Raczetal. 1961, Walter
andKucera1991), the occurrence ofinjury (Büren
1998, Keller1962, Kucera1991, Raunecker
1956, Wernsdörferetal. 2005), crown size and
socio logical status of the tree in a forest stand (Cho vanec
1974, Torelli1984, Vasilievič1974), forest
soil and geological bedrock (Büren1998,Furst
et al. 2006,Schmidtetal. 2005)etc.


Recently,a lot of authors have been dealing with an
assessment of forest stand quality impact and the impact
of tending and regeneration silvicultural methods on the
log quality from the viewpoint of the RH frequency
(Kadunc2006, Knoke2003, Kudraetal. 2003,
Prka2003, Schmidtetal. 2005). The knowledge


that generally applies is that incase of formation and
frequency of RH, forest stand age, trunk diameter and
also in some cases, group of forest types (Mahlerand
Höwecke1991)are of a significant importance. Sustaining
the whole section of beech trunk in an active profile
depends on the capacity of its crown. Considering
the value production of beech wood, the lower third of a
trunk is preferred.This part represents 90% of its value
production. This knowledge is used during intensive
crown thinning focusing on bigger target diameter
which is then achieved considerably sooner.The intensive
crown thinning has an impact on lower frequency of
RH occurrence in case when we accept the target diameter
of 40–50 cm (Kadunc2006,Kudraetal. 2003).
Silvicultural methods which create large growth space
for crop trees and so the shorter time to achieve thick dimensions
decrease the risk of wood devaluation by RH
(Knoke2002,Knokeand Wenderoth2001).


As mentionedabove,there are a lot of factors influencing
formation and dynamics of development of RH
in beech stands.The aim of the paper is to evaluate the
impact of two silvicultural techniques which create different
conditions for crown development, RH occurrence
in homogenous beech forest stands, while other
factors (soil type, stand origin, slope aspect, altitude,
etc.) are the same.


MATERIALSAND METHODS – Materijali i Metode


To verify the stated aim sample trees of beech were
chosen and processed.To maximize the elimination of
other factors the sample trees were chosen from two
compartments(CMTs)placed next to each other when
each of them was cultivated by a different silvicultural
technique. The forest stands belong into the Forestry
Enterprise of the Technical University in Zvolen and
have been monitored in detail for research purposes for
30–45 years by the employees of the Department of
Silviculture at the Forestry Faculty in Zvolen.


In the CMT513 were set up two sample permanent
plots (SPPs) in 1980. In the CMThas been used quality
crown thinning up to 1980. In 1986 and 1991 there was
done selective thinning, from 1991 to 2009 there was
done selection cutting twice with the volume of 70–80


m/ha.
The CMT514b is located next to the CMT513. It


has the same parameters group of forest types. The
CMT514b presents a set of four SPPs which have been


cultivated by crown thinning with a positive selection


since 1966 focusing on maximal release of crowns of


future crop trees.Before every thinning since that time


there were done measurements of selected dendrometric
parameters. The relative thinning weight in the
thinning interval of 5 years up to 1991 was at 16–18%.
In the 1991 the last release increment thinning was
done with the volume 24–26% from the forest stand.


The altitude of the both CMTs is 510–540 m, the
slope aspect is south-west, slope declination 20–25%,
and geological parent rock is andesite, soil type Cambisoil,
group of forest types: Fagetum pauper. Dendrometric
parameters were measured in 1986, 1991, 1997,
2001, and 2009. From two CMTs there were chosen 14
dominant trees (7+7 trees from each CMT), in the age
of 93–112years.The crown volume of selected trees


(C) was calculated according to (Jurča1968)
k


2
k


C= (./8) ×b× l(1)
wherebis the crownwidth andlis the crown length in
meter. The final dendrometric parameters are in the
Table 1.