ISSN 10674136, Russian Journal of Ecology, 2009, Vol. 40, No. 6, pp. 387–392. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © N.E. Sudachkova, I.L. Milyutina, L.I. Romanova, 2009, published in Ekologiya, 2009, No. 6, pp. 411–416.
The growth and development of trees depend on
the combination of ecological factors characteristic of
a given region. In Siberia, due to its vast north–south
expanse and complex topography, the productivity of
tree stands is limited by insufficient heat supply at
northern latitudes, waterlogging combined with dis
solved oxygen deficiency in swamped habitats, and
moisture deficiency in arid southern regions.
Researchers usually concentrate on the influence of
changes in temperature and other factors affecting the
aboveground tree parts, whereas trees growing in Sibe
ria more often suffer from stress to the root system.
The purpose of this study was to estimate the influ
ence of longterm seasonal soil freezing, waterlogging,
and drought on the growth and metabolism of Scots
pine by exposing the rhizosphere of young trees to
these stress factors simulated in experiments.
MATERIAL AND METHODS
Studies were performed with young Scots pine trees
L., age class 1) from a natural stand
formed in a cutover area of cowberry–herb pine forest,
on soddy podzolic soil, in the southern taiga subzone
of Central Siberia (Emel’yanovskii raion, Krasnoyarsk
krai). Experiments on exposing the root system to
cold, waterlogging, and drought continued over three
consecutive years. Biometric parameters of the trees
are shown in the table.
In experiments with cold exposure and drought,
observations were performed in test and control plots
5 m), each with 50–60 young trees. In the first
variant, the experiment began in midApril. The snow
on the plot was thoroughly tramped down and buried
under a 30cm layer of sawdust covered with polyeth
ylene film (with holes for the trees), on which addi
tional 30cm snow layer and 20cm sawdust layer were
Adaptive Responses of Scots Pine to the Impact
of Adverse Abiotic Factors on the Rhizosphere
N. E. Sudachkova, I. L. Milyutina, and L. I. Romanova
Sukachev Institute of Forest, Siberian Branch, Russian Academy of Sciences,
Akademgorodok, Krasnoyarsk, 660036 Russia;
Received January 11, 2008
—The impact of longterm seasonal soil freezing, drought, and waterlogging on the rhizosphere of
young Scots pine trees (
L., age class 1) has been simulated in experiments. The results have
shown that cold stress exposure leads to reduction of the rates of linear and radial tree growth and of chloro
phyll content in needles, a shift in the peak of starch content, and initiation of free amino acid deposition in
the aboveground plant parts. Drought activates utilization of carbohydrate reserves and amino acid accumu
lation in the root bast, whereas soil waterlogging stimulates deposition of carbohydrates but causes a decrease
in the levels of chlorophyll and amino acids in all plant tissues.
: Scots pine, rhizosphere, cold exposure, waterlogging, drought, chlorophyll, carbohydrates, amino
Biometric parameters of young Scots pine trees in test and control plots
Cold exposure Drought Waterlogging
control experiment control experiment control experiment
11 10 13 13 8 8
Root collar diameter, cm