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affected the species composition of plants (Grigoryev and Kondratyev 2005).
Immediately after the
fire, the diversity of species and living forms grows even
more rapidly, but in the course of the age succession to initial forest composition,
this diversity decreases.
Restoration of forest communities depends on the frequency and intensity of
fires of low intensity cause
changes in the age and quality of forest stands. Changes of forest planting are
connected with intensive but rare
fires. In the Siberian taiga forests relatively frequent
re dynamics of forest
ecosystems at the Far East of Russia show that successions of forest vegetation are
connected with
fires. Studies of the post-
fires (Efremov and Sapozhnikov 1997). At the same time, it was
shown that
fires are a needed element to maintain biodiversity.
re regeneration of forest ecosystems depends on many factors (cli-
mate, soil, rocks composition, relief, etc.). In deciduous forests of Siberia, with its
permafrost, the shrub and grass-shrub tiers are restored in 4
The post-
5 years after the
re,
-
while moss and lichen grow much slower.
Sometimes the
fires affect positively the soil component of the forest ecosystem
and, in particular, promote the preservation and provision of soil with nitrogen,
which is known to play an important role in forest ecosystems
'
productivity. This
effect has been found out by the scientists from the Montana University in Missoula
in the forests of the western part of Montana (Newland and De Luca 2000). Local
forests with prevailing yellow pine and Douglas fir develop better in the case of
abundant nitrogen-
cient content of nitrogen in soil.
It was found out that these plants are very important as a factor of compensation of
nitrogen, when the forest ecosystems loose it after the
xing plants and due to this, suf
fires. In the absence of
res,
the quantity of nitrogen-
xing plants decreases, and further on the forest structure
changes drastically. On the contrary, periodic
fires in the forests of yellow pine and
Douglas
fir, broaden the propagation of nitrogen-
xing plants and favor the forest
ecosystems
productivity, on the whole.
As mentioned above, one of the manifestations of the anthropogenic interference
into the forest ecosystems
'
dynamics is forest burning down for subsequent land use
in agriculture. As Krimmer and Lake (2001) have shown, the controlled burning-
down of forests maintains their landscape mosaic and promotes the preservation of
biodiversity, as well as raises the forest ecodynamics
'
productivity. From obser-
vations of Hoffmann (1998), in savannas serrado in Brazil, the productivity of the
ecosystem of 3 species of trees, two species of shrubs and one species of subshrub
increased 4
'
7 times after the burning. Clearly, the burning of the forest sites by
natives should be attributed to the means of their harmonious co-existence with
nature, and the planned burning of forests should be carried out on a scienti
-
c basis
and considered as an element of land use optimization (precisely, forest-use). The
problem of the balanced use of positive and negative consequences of a forest
re
remains unsolved.
One of the main problems of the forestry science is earlier detection of the
re
hazard areas. As it was shown in Chap.
1
of this topic a solution of this problem can
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