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 (R_a+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.

 Keywords: Brassica napus, CO₂ emissions, Zea mays.

Article DOI: http://doi.org/10.15544/RD.2015.036