Oganesiyan M. S., Gorban V. A., Bondar O. Y.

Oles Honchar Dnipropetrovsk National University

 PARTICULAR QUALITIES OF THE CONTENT OF CALCIUM CARBONATES IN THE ORDINARY CHERNOZEM UNDER THE SHELTER BELT OF DNIPRO PRYSAMARIYA

Calcium carbonates are ones of the chief components in the ordinary chernozem (black soil). They affect different processes in the soil, the main of which are changes in concentration and activity of calcium ions in the soil solution, the state of absorbing complex of soil, soil acidity (pH). They also help to build strong coagulation structures, provide antiwind resistance of soil, increase the mobility of some chemical elements, improve a number of water-physical properties of soil: density, water permeability, porosity, etc. Special research of carbonate morphology, micro­morphology and mineralogical composition gives information about genesis of soil and can help diagnose features of chernozem that is very important today. Carbonates are sensitive indicators of changes in the conditions of mineral formation, because they have a wide range of isomorphism in their crystal lattice, moreover they have a large variation degree of order or disorder in a structure.

Calcium carbonate has white color, it is found in various forms in the thickness of soil profile. Calcium neoplasms have extremely diverse forms that depend on environmental conditions, in which the migration of bicarbonate solutions takes place. The character of carbonate neoplasms is determined by a complex combination of factors (concentration of the soil solution, partial pressure of soil CO2 , humidity and evaporation in the middle of the soil mass, the nature of the soil profile draining, activity of soil biota, soil temperature, density and porosity of the soil profile etc.). These factors determine primarily the amount of CaCO3 and its microstructure. On the other hand, the habitus of carbonate neoplasms also depends on the structure and composition of the soil, the sizes and shapes of cavities in which the deposition of calcite crystals takes place. So all these factors naturally vary within the limits of the soil profile that causes formation of certain forms of carbonate neoplasms that are contained in the profile of chernozem and their migration.

The main purpose of our work was to investigate the characteristics of the content of calcium carbonates in the ordinary chernozem under the shelter belt of DniproPrysamariya. To establish the content of carbonates, we used generally accepted method which is based on the records of the weight loss of soil due to the allocation of CO2 in the acid destruction of carbonate.

The trial area, from which we selected soil samples for analysis of calcium carbonate content, was situated on the watershed of the virgin steppe plakora under trees of the shelter belt. The Table 1 below has our results of research.

Table 1. The content of the calcium carbonates in the ordinary chernozem under the shelter belts of the Dnipro Prysamariya

Analyzing the table information, we can say that the shelter belt trees directly affect the distribution of calcium carbonate in the soil profile. Trees of the shelter belt lead to eluvial removal of carbonates from the upper genetic horizons and their illuvial accumulation in the lower genetic horizons of the ordinary chernozem of the shelter belts improved by trees.