International Journal of Environment and Climate Change

Greenhouse gas (GHG) emissions associated with livestock, crop production and land-use change are important considerations for climate action in Nigeria. This study assessed concentrations of methane (CH₄), nitrous oxide (N₂O) and carbon dioxide (CO₂) at selected livestock and farmland sites across the country's six geopolitical zones. Field measurements were undertaken at 25 sites per zone, while annual emissions were estimated using an IPCC Tier 1 approach with activity data and specified emission factors. Livestock-site concentrations ranged from 1.90 to 3.67 ppm for CH₄, approximately 0.35 to 0.39 ppm for N₂O and 340.3 to 390.1 ppm for CO₂. Corresponding farmland concentrations ranged from 80.44 to 157.2 ppm, 0.293 to 0.330 ppm and 555.21 to 775.31 ppm, respectively. An illustrative emissions inventory based on 150 livestock heads and 100 ha of farmland yielded a total of 67,738,300.75 kg CO₂e/year. Within this estimate, soil-carbon losses associated with land-use change accounted for 67,100,000 kg CO₂e/year, exceeding the contributions of rice cultivation, livestock and nitrogen-related activities. A projection scenario considered annual livestock growth of 2% with farmland area held constant through 2030. The findings identify soil-carbon conservation, improved manure management, more efficient fertiliser application and alternative water management in rice cultivation as relevant mitigation considerations. Further validation of activity data, emission estimates and projections is required before extrapolating these results to national agricultural emissions.