Energy Use Efficiency and Carbon Footprints in Rice–Mustard–Rice and Rice–Wheat–Mungbean Systems under Conservation versus Traditional Agriculture

This study evaluates energy use efficiency, productivity, profitability, and carbon footprints of conservation agriculture (CA) compared to traditional agriculture (TA) in intensified rice-based cropping systems in Mymensingh district of Bangladesh. On-farm trials were conducted during 2015–2017 compared rice–fallow–rice and rice–wheat–fallow (TA) with rice–mustard–rice and rice–wheat–mungbean (CA) using a randomized complete block design. Results revealed that the CA reduced total energy inputs by 23–42%, increased energy use efficiency to 8.83–11.76 and raised total energy output to 428–434 GJ ha ^− 1 , nearly doubling energy use efficiency. System productivity increased by 48–54% (21.2–22.4 t ha ^− 1 ), benefit–cost ratio rose by 32% (1.66–1.94), and carbon footprints declined by 25–34%, indicating a 25–33% reduction in global warming potential to 4.85–5.70 t CO ₂ e ha ^− 1 . CA enables sustainable intensification by increasing renewable energy use, reducing non-renewable inputs, and improving economic viability. These results support CA as a climate-smart pathway for sustainable agriculture in South Asia.