С budget in the agroecosystems of maize (Zea mays L.) and rapeseed (Brassica napus L.)

Abstract

The aim of this research was to calculate and compare the C budget changes for maize (Zea mays L.) and rapeseed (Brassica napus L.), identifying soil seasonal respiratory CO2 (Ra+h) and assimilated photosynthetic CO2 at plant different growth stages. The research was carried out for maize (Zea mays L.) and rapeseed (Brassica napus L.), during the vegetation period (2014 June – September) at the PI ASU Training Farm, Kaunas district. The mean soil CO2 emissions were 1.971±0.12 µmol m-2s-1 for maize, and 2.199±0.25 µmol m-2s-1 for rapeseed. The highest measured soil CO2 emissions 2.432±0.23 µmol m-2s-1 for rapeseed in June, and 2. 963±0.28 µmol m-2s-1 for the maize in the second half of July. The mean C budget in maize agro-ecosystems was 15.54 t ha-1, while it was 10.30 t ha-1 in rapeseed