Energy and carbon footprints of wheat establishment following different rice residue management strategies vis-a-vis conventional tillage coupled with rice residue burning in north-western India

摘要

Energy and carbon (C) footprints have close nexus in agriculture. Agri-inputs are energy intensive and lead to significant C equivalent (CE) emissions. We studied energy and C footprints during wheat establishment following different rice residue management (RRM) strategies: residue retention with Happy Seeder (HS); removal after bailing + zero till drill (ZT); incorporation with rotavator tillage + drill (RT) and mould board plough tillage + drill (MBP) vis-a-vis burning + conventional tillage + drill (CT)to identify options for balancing energy, C footprints and C sequestration. Total energy input (E_I) with residue retention was significantly (p ＜ 0.05) lower by 1540.9-3884.5 MJ ha~(-1) (5.9-13.8%) than residue removal/burning. Although, energy output (E_O) was significantly lower with residue retention/removal, yet energy productivity (E_P) did not differ significantly. Total CE emissions were highest in CT and lowest in ZT. Fertilizer-N was the major hotspot of energy (37.5-45.2% of E_I) and C footprints (53.6-87.9% of total CE emissions). As compared to CT, residue retention offers reduction in C and energy footprints -14.1 and 12.9%, respectively. Results reveal that rice residue burning is not a viable option as it leaves high C footprints and lowers the amount of C added to soil organic C pool and C sustainability.