Tillage systems influence on greenhouse gas emission factor and global warming potential under rice-mustard-rice cropping system

Conventional tillage (CT) degrades soil and environmental quality in many major cropping systems. Conservation agriculture, like reduced tillage, can play an important role in maintaining soil organic carbon (SOC) storage and in minimizing greenhouse gas (GHG) emissions from crop fields. An experiment was conducted at the Bangladesh Agricultural Research Institute (BARI), Gazipur to evaluate GHG emission, global warming potential (GWP), GHG intensity and net SOC variations in rice-mustard-rice cropping systems under CT and strip tillage (ST). The emissions of nitrous oxide (N2O) and carbon dioxide (CO2) varied significantly because of CT and ST tillage practices. The ST reduced 24-47% methane (CH4) emission factor, 20-32% CH4 flux, 32-46% GHG intensity and 31-47% GWP than CT practice. In mustard crop, ST reduced 55-61% of GHG intensity and 52-58% of GWP compared to CT. There was about 33% increase in N2O emission and 24% augmentation of soil respiratory CO2 with ST compared to CT. About 8% absorption of net ecosystem CO2, 9-11% of net SOC and 10% of rice equivalent yields increased in ST compared to CT. It is concluded that ST can minimize soil C loss, improve net ecosystem CO2 absorption, and reduce GHG intensity, GWP under rice-mustard-rice systems in Asian countries.