Effect of nitrogen dioxide on nitrite oxidation and nitrite-oxidizing populations in soil

When nitrogen dioxide was added to soil at a rate equivalent to 51μg Ng^?1 soil, the nitrite formed was oxidized logarithmically. The numbers of nitrite-oxidizing microorganisms also increased logarithmically, but the final count was too low to account for the amount of nitrite metabolized. In soil treated with NO₂ at a rate equivalent to 106μg Ng^?1, the nitrite formed was oxidized, but the counts of autotrophic nitrite oxidizers did not rise. Discrepancies between predicted bacterial numbers and nitrifying activity were also noted in soils amended with nitrite.