well as field moisture in samples of undisturbed soil – with a thermostatic and weight
ending; – conductivity – conductometrically, with the help of EZODO-8200 (DSTU
ISO 11265:2001).
Tests were carried out in three to five repetitions. The obtained soil indexes were
processed by means of mathematical dispersion method using correlation analysis via
systems of Excel spreadsheets.
Research findings. Granulometric composition, as a parameter of soil solid
phase’s dispersion, is an important factor in many physical and chemical processes,
which gives an idea of its provision with mineral components, including nutrients. It is
known that each particle fraction is individual in size and in terms of physical and
chemical properties. The particles, fragmented to the size of colloids, have a number
of features that are alien to crude dispersed (dusty and sandy) particles. In such a way,
excess energy is formed on the surface of the crushed particles, and as a result the
molecules and atoms located in their midst are in different conditions with those on the
surface. Therefore, colloids are rather active in chemical reactions, while only those
molecules and ions that are present on the surface of colloidal particles are interacting.
In accordance with the increase in the content of smaller particles, their chemically
active surface increases, and the number of molecules and ions that can enter into
chemical reactions (including neutralization reactions) increases as well.
It was established that granulometric composition of soils varies greatly and has
a high coefficient of variation in almost all soils. The productivity of forest soils
depends on it greatly. Types of forest vary depending on the granulometric composition
[3].
At the same time, A.F. Tiulin thinks that nutrients such as nitrogen and
phosphorus are mainly concentrated in particles lesser than 0.01 mm (which are almost
completely aggregated with water-resistant aggregates and are more available to the
roots of plants) are of great importance for mineral feeding. Particles larger than 0.01
mm serve as a reserve for gradual weathering of minerals. The development of a solid
turf from thin plants' roots leads to the accumulation of nutrients on the surface of
particles larger than 0.01 mm and prevents them from weathering. Therefore, studying
the soil aggregation, types of this aggregation, genesis of aggregates, their structure,
identification of true water resistance are necessary for the disclosure of ecological role
of forest edaphotops' micromorphological organization.
Our research objects, deep typical black soils under different vegetation cover, are
characterized by the predominance of physical clay (53-65%) fractions over the sandy
fraction of soils.
Silt and physical clay are evenly distributed over the profile of black soils. The
amount of silt and physical clay gradually decreased with depth on the soils' profile,
- 60 -