I. A. Bobrenko, Yu. V. Aksenova
Stolypin Omsk State Agrarian University, Institutskaya pl., 1, Omsk, 644008, Russian Federation
Abstract. The purpose of the study was to develop models of soil fertility, focused on the formation of high and stable crop yields in the Omsk region. The models were developed as a result of studying soil parameters in field experiments conducted in 1976–2020. The objects of the study were sod-podzolic soils of the taiga-forest zone, ordinary and southern chernozems, meadow-chernozem soils, and deep solonetzes of the forest-steppe and steppe zones. The models were based on indicators of soil properties that closely correlate with the yield of grain and row crops. The agronomic value of soils was determined by the thickness of the humus layer, humus content, and granulometric composition. The optimum thickness of the arable layer was 25–30 cm. In the aggregate composition, 50–70% should be occupied by fractions ranging in size from 10 mm to 0.25 mm; the lumpy fraction (less than 10 mm) should not exceed 20–40%. In the steppe and southern forest-steppe zone, the granulometric composition is considered favourable with the amount of physical clay 45–60%; for solonetzes and soddy-podzolic soils, this indicator should be 30–40%. The optimal humus content for sod-podzolic soils is 2.5–4.0%; for chernozems, meadow-chernozem soils, and solonetzes it is 5.5–6.5%; the content of mobile forms of phosphorus and potassium is 120–260 mg/kg of soil; the content of mobile forms of nitrogen is 15–26 mg/kg of soil. Since soils, especially sod-podzolic ones, are poor in microelements, there are scales to calculate their optimal provision with cobalt, copper, molybdenum, etc. Soils of the forest-steppe and steppe are largely subject to alkalinization, salinization, and erosion processes. The content of exchangeable sodium in soils of the chernozem series must be maintained within 5% of the capacity of cation exchange; for solonetzes, this indicator should be no more than 20%. Depending on the type of soil, readily soluble salts should be located at a depth of 80–200 cm. Slight soil erosion is permissible.
Keywords: fertility model; chernozem; solonetz; meadow-chernozem soil.
Author Details: I. A. Bobrenko, D. Sc. (Agr.), head of department (е-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.); Yu. V. Aksenova Cand. Sc. (Biol.), assoc. prof. (е-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.).
For citation: Bobrenko IA, Aksenova YuV [Fertility models of arable soils in the Omsk region]. Dostizheniya nauki i tekhniki APK. 2021;35(5):9-14. Russian. doi: 10.24411/0235-2451-2021-10501.