GHG emissions and carbon footprint in wheat cultivation practices in Bihar state of India

Wheat, the second most cultivated crop globally after rice, is a major source of food and nutrition but also contributes significantly to greenhouse gas (GHG) emissions. In the context of climate change, it is important to evaluate cultivation practices not only for their productivity but also for their environmental sustainability. This study assessed conventional tillage and no-tillage wheat production systems in Bihar, India, focusing on CO₂-equivalent emissions, energy use, carbon offset potential, and the carbon sustainability index (CSI). Total GHG emissions from agricultural inputs ranged from 1745.66 to 2239.27 kg CO₂-eq ha −1 , with indirect energy sources being the largest contributors in several no-tillage variants. Among the systems studied, NT-6 recorded the highest carbon offset (2597.12 kg CO₂-eq ha −1 ), while NT-3 achieved the lowest net carbon emission (16.76 kg CO₂-eq ha −1 ). Conventional practices such as CP-12 were more emission-intensive and heavily dependent on non-renewable energy, whereas no-tillage systems consistently showed lower emissions, higher carbon efficiency, and improved sustainability. The maximum CSI value (0.079) was obtained under NT-4, while CP-1 had the lowest (−0.363). These results demonstrate that no-tillage is not only a low-emission option but also a more energy-efficient and sustainable production system that aligns with climate-smart agriculture. The findings provide evidence-based guidance for policymakers, planners, and farmers to adopt conservation practices that enhance wheat productivity while reducing the environmental footprint, thereby supporting climate change mitigation and long-term agricultural sustainability.