Intake and fixation of organic carbon in grain agrophytocenosis of Western Siberia

Abstract

Abstract In nature, carbon plays an important role in the circulation of organic matter in the soil-plant-atmosphere system. To understand the full picture of the farming system impact on carbon dioxide emissions, long-term stationary experiments are needed, which will reduce the influence of weather conditions on changes in organic carbon stocks in soils and develop an optimal model of the crop cultivation system considering the positive balance of organic carbon in soils. The research was carried out from 1995 to 2020 in the grain crop rotation at the station of the Department of Soil Science and Agrochemistry of the SAU of the Northern Trans-Urals, near vil. Utyashevo in the Tyumen region. Purpose. The purpose of the research was to establish the effect of increasing doses of mineral fertilizers on the intake and fixation of organic carbon with plant residues in the grain agrophytocenosis in the conditions of the forest-steppe zone of the Trans-Urals. The refusal to use mineral fertilizers leads to annual losses of organic carbon in the form of CO2 up to 0.6 t/ha. The use of high doses of mineral fertilizers for the planned yield of 5.0 and 6.0 t/ha of grain annually increases the emission of CO2 by 0.4-0.6 t/ha per year. In these variants, the carbon received from plant residues is not fixed in the soil. A positive balance of organic carbon is provided only by the use of doses of mineral fertilizers for the planned yield of 3.0 and 4.0 t/ha of grain, which annually increases the carbon stock in the soil by 0.4-0.6 t/ha, and up to 14-21% is fixed from the incoming organic carbon in the form of plant residues in the soil.