Lime (calcium carbonate) is a powerful tool for improving nutrient availability, productivity and reducing greenhouse gas emissions.
Nitrous oxide is a long-lived gas and is produced from fertiliser and animal urine along with industrial processes. In Agriculture, these losses occur regardless of whether N Fertiliser is applied or not, they are a function of a fertile soil. However, inappropriate use of N fertiliser can exacerbate these losses.
Denitrification is a process of reduction and one of these losses is through nitrous oxide (N₂O) escaping to the atmosphere through incomplete denitrification occurring under anaerobic conditions. The enzyme responsible for the final step of denitrification, nitrous oxide reductase, is inhibited in acidic soils. Thus, low pH combined with waterlogged conditions creates a “perfect storm” for N₂O emissions.
Lime raises soil pH, enabling complete denitrification and reducing N₂O emissions. Studies from New Zealand, Ireland, and Denmark show that liming improves soil conditions, enhances microbial activity, and increases plant biomass—factors that collectively reduce the availability of nitrogen for denitrification and limit anaerobic conditions.
