Carbon dioxide concentration in soil. Effects on nitrification, denitrification and associated nitrous oxide production

Abstract

Experiments were conducted to study the effects of a range of CO2 concentrations (ambient to 100%) on nitrification, denitrification and associated nitrous oxide (N2O) production in a silt loam soil. It was found that increase in CO2 concentration from 0.3 to 100% CO2 increasingly retarded the rate of nitrification. No nitrification occurred at 100% CO2. Nitrous oxide production associated with nitrification increased as CO2 increased from 0.3 to 2.6% and tended to be greater as CO2 concentration increased to 73%. At 100% CO2, no N2O was produced during 7 days at 25°C