Effect of organic and conventional farming practices on the greenhouse gas emissions and stable organic carbon in rice-onion rotation cropping system

This study aimed to evaluate the greenhouse gas (GHG) emission rates and the stable organic carbon content in organic and conventional systems during rice-onion cropping season.Methane (CH 4 ) and nitrous oxide (N 2 O) emissions rates were investigated using the closed chamber method.As a stable carbon, mineralassociated organic matter (MAOM) and humic substances were selected and determined through physical and chemical fraction methods.During the rice and onion growing seasons, the CH 4 and N 2 O emissions patterns exhibited similar trends in both organic and conventional practices.However, the total greenhouse gas emissions in the organic was notably lower than conventional farm, and the impact of the rice season (70%) was much higher than onion.Furthermore, humic substances and MAOM were 14% and 13% higher, respectively, in the organic system compared to the conventional system (p < 0.05).This suggested that organic farming management could contribute to mitigating climate change by reducing GHG flux and increasing stable soil organic carbon.