Quantifying the energy use efficiency and greenhouse gas emissions in Punjab (India) agriculture

It is inevitable to acknowledge the greenhouse gas emissions (GHGE)’s primary role in the planet's rising temperatures, which poses threat to ecosystem's sustainability. In India, a 18% of the total GHGE comes from agriculture. Agricultural systems, being complex, need highly efficient energy usage to ensure better yields, and hence, farmer income and food security. Within India, Punjab is the state with greatest agro-economic impact. Therefore, present study is an attempt to quantify the GHGE and energy use efficiency (EUE) in major crops (cotton, maize, paddy, wheat, and sugarcane) of Punjab based on 2019–2020 data. Results revealed that the direct energy and non-renewable energy contribution significantly exceeded the indirect energy and renewable energy, in all crops except sugarcane. Electricity and fertilizers were noted as key areas for energy sink for all crops studied. The specific energy based on economic yield was realized to be significantly higher in cotton (10.23 MJ Kg⁻¹), followed by paddy (5.28 MJ Kg⁻¹), and less than 5 MJ Kg⁻¹ for other crops. High energy intensity indicates that there exists a better potential for further improvement in the energy productivity of cropping systems. In terms of total input-output energy, net energy gain and EUE, sugarcane was noted to be at the top, followed by paddy among other seasonal crops. Paddy was found to emit the highest CO₂ eq. emissions (6718 kg CO₂ eq. ha⁻¹) of all crops and around 60% was contributed solely by methane (CH₄) due to paddy cultivation in submerged water. Thus, optimizing fertilizer rates, precisely guided irrigation systems, adoption of resource conservation technologies (RCTs) i.e., DSR, Laser leveling, minimizing crop residue burning, and using them for energy supply are among best possible alternatives for improving EUE and reducing GHGE.