Nitrification is the conversion of inorganic or organic nitrogen from a reduced to a more oxidized state. Chemoautotrophic bacteria are largely or solely responsible for nitrification in soil with a pH above 5.5 (Focht and Verstraete 1977), at a lower pH there is evidence for the presence of acid-tolerant heterotrophic nitrifiers (Schimel et al. 1984). The heterotrophic nitrifiers (e.g. few bacteria, such as strains of Arthrobacter, and fungi, such as Aspergillus) do not derive energy from the oxidation of NH4+. In arable soils the production of nitrate by heterotrophs appears to be insignificant in relation to that brought about by the chemoautotrophs (Paul and Clark 1989). In contrast, 90% of the potential nitrification in acid forest soils is produced by heterotrophs (Kilham 1987).
Weitere Kapitel dieses Buchs durch Wischen aufrufen
- Nitrification and Denitrification
Prof. Dr. Franz Schinner
Dr. Richard Öhlinger
Doz. Dr. Ellen Kandeler
Dr. Rosa Margesin
- Springer Berlin Heidelberg