Nitrifying populations and the destruction of NO2 sorbed by soil

Journal Article · Thu Jan 01 04:00:00 EST 1976 · Am. Soc. Microbiol., Abstr. Annu. Meet.; (United States)

OSTI ID:6253793

Ghiorse, W C; Alexander, M

Nitrifying microorganisms participate in the destruction of NO2 sorbed by soil by oxidizing the nitrite formed as a sorption product. The nitrite oxidation rate increases and shifts away from linearity as soil moisture increases to field capacity. At constant soil moisture levels, the rate of nitrite oxidation in samples preexposed to NO2 is greater than in samples not preexposed, suggesting adaptation and/or growth of a nitrifying population. However, inhibition of nitrite oxidation by 1mM but no 0.01mM chlorate suggests that, if autotrophs are involved, a resting rather than a growing population carries out the oxidation. Nitrobacter numbers in the soil rise only after at least half of the nitrite initially formed from NO2 is oxidized, but the population increase does not produce a corresponding increase in nitrite oxidation rate. Heating the soil to 42-45 C for 6 h reduces Nitrobacter numbers and retards but does not eliminate nitrite oxidation. No increase in Nitrobacter numbers is observed during nitrite oxidation in the heated soil. These results and estimates of nitrite turnover per autotrophic cell suggest that Nitrobacter is not a major contributor to nitrite oxidation in this soil, but heterotrophic nitrifiers may be involved in this mechanism for the destruction of NO2.

• Research Organization: Cornell Univ., Ithaca, NY
• OSTI ID: 6253793
• Journal Information: Am. Soc. Microbiol., Abstr. Annu. Meet.; (United States), Journal Name: Am. Soc. Microbiol., Abstr. Annu. Meet.; (United States) Vol. 76; ISSN ASMAC
• Country of Publication: United States
• Language: English

Related Subjects

560302* -- Chemicals Metabolism & Toxicology-- Microorganisms-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BACTERIA
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
MICROORGANISMS
NITRATES
NITRIFICATION
NITROGEN COMPOUNDS
NITROGEN DIOXIDE
NITROGEN OXIDES
OXIDES
OXYGEN COMPOUNDS
SOIL CHEMISTRY
SOILS
SORPTION