Nitrifying bacteria abundances

Table 5.1 Abundances of Nitrifying Bacteria Reported from Aquatic Systems... 

The nitrifying bacteria are also very sensitive to high temperatures. Their populations are substantially reduced by exposures to temperatures of 212°F (100°C), and they are virtually eliminated at temperatures hotter than 284°F (140°C). As a result, nitrifying bacteria are often uncommon after a ground fire. The rates of nitrification are correspondingly small, even if there is an abundant substrate of ammonium. 

Marine nitrifying bacteria, especially the N02 oxidizers are ubiquitous in the world ocean and key to the regeneration of NOs, which dominates waters below the well-illuminated, euphoric zone. However they are never very abundant and, at least for those species in culture, grow very slowly. Certain heterotrophic bacteria can also oxidize NH4" " to both N02 and N03 during metabolism of preformed organic matter. However, very little is known about the potential for heterotrophic nitrification in the sea. 

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