Study: Limiting factors
at treeline afforestations, Vitosha Mountain
Aim of this Study is to determine the
most important limiting factors at the treeline afforestations
on Vitosha Mountain. It is a part of the PhD study of Eng.
PhD Momchil Panayotov, Dendrology Department
of the University of Forestry, Sofia
Prof. Stefan Yurukov, Dendrology Department, University
of Forestry, Sofia
The study site in Vitosha mountain
is nearby Aleko hut at the end of the wide plateau, on which
is situated “Torfeno braniste” reserve.
About sixty years ago in this region there have been carried
out plantings with Macedonian pine (Pinus peuce Griseb.),
Norway spruce (Picea abies Karst.), Scots pine
(Pinus sylvestris L.) and limited number of mountain
pine (Pinus mugo Turra ssp. mugo ) and
Bosnian pine (Pinus heldreichii Christ).
The trees have experienced strong
influence from winds, snow drift, rhyme accumulation and
occasionally ice accumulation during freezing rains.
At the present moment there are big differences in the condition
of the trees from the separate species and from one and
the same species, but found on micro sites with different
growth conditions. This provides the opportunity to study
their reactions to disturbances and compare their resistibility.
Three permanent and three temporary
plots have been marked in the region. Three of them are
in plantings of Macedonian pine (Pinus peuce Griseb.),
two in plantings of Scots pine (Pinus sylvestris
L.), one in a natural forest of Norway spruce (Picea
Position of permanent Pinus
peuce plots (N1 and N2), temprorary Pinus peuce plot (N3)
and permanent Pinus sylvestris plot (N4). The rest of the
plots are in the forest beyond the visible ridge.
In the plots have been made measurements
of H, Dbh, Crown dimensions and extracted cores for Dendroecological
analysis. In two of them (treeline plots N1 and N2) have
been recorded coordinates of the trees and composed digital
maps with the use of ArcGIS 8.3 Software.
At the present moment the state of almost
all Scots pine trees is very bad. They have flagged crowns,
skewed stems with numerous breakages and slow growth.
Scots pine tree with flagged crown at the treeline in
the region of Aleko hut
The state of Macedonian pine plantings is normal, but there
are zones at about 20m behind the edge of the plantings
with strongly deformed trees. Snow measurements during the
winters of 2004 and 2005 show that there are huge accumulations
of snow in this zone. Dendroecological analysis shows a
strong relation of stems damages periods with winters with
higher than normal snow accumulations.
In afforestations of Macedonian pine there are huge
snow accumulations in a zone starting aproximately 20m behind
the front edge of the plantations. In this zone many of
the trees have been broken or bent
The state of Norway spruce trees is observed in natural
forest groups. As a species, that naturally forms treeline
in Vitosha Mountain, Picea abies is well adapted for local
conditions and together with Macedonian pine regenerates
Although there are a limited number of Bosnian pine (Pinus
heldreichii Christ) trees gathered in small groups,
they are also object of interest. In Vitosha mountain this
species does not grow on its preferred calcareous soils,
but it performs very well and the initial observations show
that it suffers only from occasional desiccation. Stems
have normal forms, heights and diameters.
Presentations and publications from this
Results from this work have been
presented on the 4-th Tree Rings in Archaeology, Climatology
and Ecology (TRACE) conference, held from 21 to 23 of Apil
2005 in Fribourg, Switzerland and on the “Young Scientist”
Conference, held from 17 to 18 of May 2005 in Sofia.
Panayotov, M.P. (2005) Dendroecological
analysis of the influence of extreme climate events. Forestry
Ideas, 2005, in Bulgarian, English abstract
Panayotov M., S. Yurukov (2005): Dendroecological
analysis of the influence of strong winds and snow accumulation
on the growth of trees at the treeline in Vitosha Mountain,
Bulgaria. Tree Rings in Archaeology, Climatology and Ecology
(TRACE 2005) Proceedings, April 21st-23d 2005, Fribourg,
Switzerland: 164-173- available
at our site, PDF file, 1.3 MB
Panayotov M (2005): Influence of strong
winds and snow accumulation on the growth and development
of Macedonian pine (Pinus peuce Griseb.) plantations
in the treeline zone of Vitosha Mountain. Young Scientists
Conference Proceedings, May 17-19-th 2005, Sofia, Bulgaria.
follow the link to download PDF file, 1,5MB)
Dr. Momchil Panayotov, e-mail:
mp2@ abv.bg (Please note: there is an empty
space after the "@" symbol. Youi have to remove
it to send e-mail)