GEOGRAPHIC AND GENETIC FEATURES OF THE DEHUMIFICATION OF THE UKRAINE STEPPE ZONE SOIL

S. Korliuk, V. Mykhailiuk

Abstract
    Comparative analysis of modern researches and materials of Ukraine steppe zone soil large-scale surveys, conducted by Professor Nabokikh O.G. in 1914-1915 years, showed the significant differences in the current humus state of soils as compared with the humus state in the beginning of the XXth century. At the same time, the data of modern agrochemical monitoring point to that there was a rapid decrease in the humus content in the soils of southwestern Ukraine in the 1990 to 2000 period, which was caused by a violation of the dynamic equilibrium between the intake of organic substances (a decrease in the norms of organic fertilizers) and the destruction of humus as a result of the agricultural use. At the present time, the new quasi-equilibrium humus state of the soils has been formed in accordance with modern agro-ecological conditions.

Key words: agricultural use of soils, chernozems, dehumification, Ukraine