Effect of cabbage species on CO₂ emission from soils in case of short-term green manuring of fallow fields in the Baikal region

Siberian Institute of Plant Physiology and Biochemistry, Siberian Branch, Russian Academy of Sciences, Irkutsk, 664033 Russia

^* Corresponding author: zorina@sifibr.irk.ru

Abstract

The formation of the seasonal CO₂ flux depending on the species of cabbage crops used for short-term summer green manuring of the fallow field in the Baikal forest-steppe zone was studied. In field experiments on gray forest soil during the warm season, CO₂ emission rates per day were measured in options with white mustard (Sinapis alba L.) and oil radish (Raphanus sativus var. oleifera Metzg). The black follow served as the control. The total CO₂ flux from the soil was calculated by identifying different periods in the fallow treatment technology (before sowing green manure crops, vegetation, and the period after biomass plowing). An increase in the intensity of CO₂ release from the soil after the plowing of green mass was revealed. The enhancement of mineralization processes due to the newly received organic matter of mustard biomass was 27-100%, and radish - 48-142% in relation to the black fallow. The CO₂ emission data corresponded with the yield and quality indicators of the studied cabbage crops. It has been established that from the position of regulation of carbon dioxide fluxes, the use of white mustard for short-term green manure in the conditions of the region is more expedient than oil radish.