Increasing soil pH reduces fertiliser derived nitrous oxide emissions

An Irish research project summary found that raising soil pH reduces nitrous oxide (N2O) emissions from fertilizer in intensively managed temperate grasslands. By improving soil pH, farmers enhance crop productivity and help reduce harmful greenhouse gas emissions, creating a win-win for both agriculture and the environment. Soil pH is a key factor influencing various physical, chemical, and biological processes. It regulates microbial activity, contributing to N2O emissions and grassland productivity. The research showed that applying 5 tonnes of lime per hectare every 3-4 years increased soil pH from 5.1 to 6.9, leading to a 39% reduction in N2O emissions. Over the past 12 years, improvements in grassland soil pH across Ireland have potentially reduced national N2O emissions by 95,000 tonnes of CO2 equivalent per year. If all remaining acidic soils were brought to optimal pH, emissions could be reduced by an additional 254,000 tonnes of CO2-equivalent per year."