land, and these values are in the smallest significant difference. This difference is also
not that significant in the deeper layers of investigated rotational black soils.
The largest fluctuations of electrical conductivity of typical black soils' water
suspensions occur in the upper studied layers. In the middle of the profile, there is no
significant fluctuation seen. There is nearly no change of electrical conductivity in all
variants of use (rotation land, forest belts, arable land, tree plantations) at the depths of
undersolum.
In such a way, the rotation variants of use at the depth of 0-20 centimeters are
characterized by conductivity in the range of 120,0-130,0 μS/cm. These figures are the
largest among the researched options. The opposite situation is observed under typical
arable black soil. Here the electrical conductivity is the smallest – 47.0 μS/cm. Under
the field-protecting forest plantations (oak), the parameter is within the range of 82.0-
89.0 μS/cm. These values are followed by those of the larch (77.0 μS/cm). Somewhat
different values were obtained under pine and birch, but they are within the slightest
significant difference.
CONCLUSION
All of the abovementioned makes it possible to effectuate a main conclusion that
there is a humus-accumulative process of soil formation developing under the forest
cultures. They do not have any signs of podzolization, and on the contrary – forest
vegetation contributes to the improvement of physical (granulometric and
microaggregate composition, steady-state and soil's solid phase density, structural
state), hydrophysical (capillary, total and field moisture capacity, maximum
hygroscopicity) and electrophysical (electrical conductivity of water suspensions)
indicators, increase of fertility, and soils continue to develop according to the humus-
accumulative process of soil formation.
Along with forest cultures there comes black soils rotation method. Prairie
restoration also has a positive effect on the studied parameters, while prolonged tillage
leads to deterioration of the entire complex of physical indicators, which results into
formation of agrogenic soils.
BIBLIOGRAPHICAL REFERENCES
1. Dokuchaev, V.V. (1901). O pochvovedenii [On Soil Science] // Lektsii
professora V.V. Dokuchayeva i A.F. Fortunatova. Poltava: Ekon. byuro Polgav, gub.
zemstva. [in Russian].
2. Sokolovskiy,
A.N.
(1956).
Sel'skokhozyaystvennoye
pochvovedeniye
[Agricultural soil science]. Moskva: Sel'khozgiz. [in Russian].
3. Zonn, S.V., Kuz'mina, Ye.A. (1960). Vliyaniye khvoynykh i listvennykh porod
na fizicheskiye svoystva i vodnyy rezhim vyshchelochennykh chernozemov [Influence
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