The effect of biochar addition on N2O and CO2 emissions from a sandy loam soil - The role of soil aeration

► We investigate the effect of biochar addition on soil nitrous oxide (N2O) emissions. ► Soil N2O production is suppressed by 49% with biochar within 48 h of wetting. ► Increased soil aeration resulting from biochar addition cannot explain this effect. ► Extractable nitrate concentrations in soil decrease with biochar addition. ► We suggest that immobilisation of nitrate is increased in biochar amended soil.