Energy and Carbon Footprint in Maize and Wheat Production: Impact of Tillage, Residue and Nitrogen Management in Indo-Gangetic Plains

Continuous adoption of the rice-wheat system in the Indo-Gangetic plains has led to soil health depletion, escalating production costs and rising carbon footprints. In this regard, a field experiment was conducted in the research farms of ICAR-IARI.

The experiment was conducted in a split-plot design and had three crop establishment practices (Zero tillage with residue retention (ZT + R), Zero tillage (ZT) and conventional tillage (CT) and four nitrogen placement methods, viz. control, recommended dose of nitrogen (RDN), improved RDN and improved 80% RDN with varying application timings and doses. The study optimised nitrogen use and crop yields under different tillage and nitrogen management practices.

For both maize and wheat, the ZT had lower energy inputs than CT. Total output energy was higher in the ZT + R by 8.46% and ZT by 4.98% compared to CT for maize, while in wheat it was 9.48% and 2.06% compared to CT. energy use efficiency (EUE) was higher in ZT than CT by 26.28% for maize while in wheat, the ZT + R had higher energy use efficiency than CT by 22.6%. Carbon inputs were lower in ZT, with higher carbon efficiency and carbon sustainability index (CSI) in the ZT and ZT + R. Control plots had higher EUE and energy productivity. Improved RDN among NPMs had significantly higher total output energy, energy use efficiency than the RDN due to higher yield obtained in the improved RDN. The research highlights the benefits of ZT and the ZT + R in maize and wheat, reducing energy inputs, increasing efficiency and productivity and lowering carbon emissions. Along with it, the improved nitrogen application techniques like the subsurface placement of nitrogen improves carbon and energy parameters of maize and wheat in maize-wheat system.