Assessment of fallow grey forest soils fertility in sub-taiga zone of Omsk Priirtyshye

Omsk state agrarian University named after P. A. Stolypin, 1, Institute sq, 644008 Omsk, Russia

^* Corresponding author: yua.azarenko@omgau.org

Abstract

There is a need to obtain information on the current state of their properties when reintroducing fallow soils into arable land. The aim of the research was to study fertility indicators of grey forest soils (Luvic Greyzemic Phaeozems) The research area was located in the city of Tara, Omsk region (south of Western Siberia). A field survey of soils and vegetation cover was carried out in plots with different age of fallow land with the establishment of the value of the above ground mass. The results of the research showed that the fallow area with age of less than 10 years is represented by a thick grey forest soil, with age of 10-20 years - by a medium thick grey forest soil. The value of air-dry aboveground mass of plants varied from 1.01 to 1.01 2.58 t/ha. High density, low porosity, and aeration porosity were found in soils throughout the profile. The humus content and reserves in soils are low and average; its distribution in profiles is markedly decreasing. Reaction of soil medium is acidic (рН=4.4-4.8). The sum of exchangeable cations in humus horizons is elevated and high. In composition of cations calcium prevails (71.5-74.9 %) with magnesium share - 22.4-26.9 % and insignificant content of sodium (1.6-2.5 %). The surveyed soils can be reintroduced to arable land. However, it is necessary to provide measures to reduce acidity, improve organic matter balance, reduce density, and increase porosity of upper and subsoil horizons.