Estimating the Carbon Footprint of Cover Crops and Various Methods of Its Processing

Abstract

The aim of the research is to evaluate the impact of cover crops on CO2 emissions into the atmosphere by calculating the carbon footprint during the cultivation of white mustard (Sinapis alba L.) and oilseed radish (Raphanus sativus var. oleiferus), followed by incorporating the biomass into the soil. The study was conducted at the experimental field of the Agrobiotechnology park of Kazan State Agrarian University in the village of Narmonka, Laishevsky District, Kazan, from May to September 2023. The soil at the experimental site is gray forest soil, sandy loam in texture. The field experiment included growing cover crops followed by incorporating the biomass into the soil using three methods: traditional plowing, disking, and mowing without soil treatment. The total CO2 emissions from soil respiratory activity in plots with white mustard during mowing, disking, and plowing over the growing season amounted to 361, 469, and 674 kg CO2/ha, respectively; while for oilseed radish under the same treatments, emissions were 368, 501, and 684 kg CO2/ha. The total CO2 emissions from agricultural practices ranged from 93 to 130 kg CO2/ha depending on the last treatment method used. The CO2 captured in plant biomass significantly differed depending on the crop type: for white mustard, it was 18.605 kg CO2/ha; for oilseed radish, it was 10.560 kg CO2/ha. The calculated carbon balance showed that the difference in carbon dioxide emissions (∆CO2) when mowing white mustard was -18.145 kg/ha; for disking -18.004 kg/ha; and for plowing -17.791 kg/ha. For oilseed radish, lower values were established: -10.107 kg/ha; -9.991 kg/ha; and -9.756 kg/ha, respectively. Growing white mustard is an effective method for capturing carbon from atmospheric air. The carbon balance is most influenced by the amount of carbon captured in plant biomass and the agricultural practices applied.