The influence of different O
2 concentrations on denitrification was studied in an agricultural soil. In both nitrate and nitrite amended soil, denitrification was not observed until the O
2 concentration decreased to 0.20 and 0.21
mol/ml, respectively. Denitrification was not observed in soil samples with O
2 concentrations above 0.28
mol/ml in the gas phase. These findings suggest that a completely anoxic environment is not required for denitrification to occur in soil.
Key words Denitrification - Oxygen - Nitrite - Nitrate - Soil - Acetylene blockage