Oceanic distribution of ammonium-oxidizing bacteria determined by immunofluorescent assay ( North Pacific, North Atlantic, Chesapeake Bay).

Samples were collected from the coastal waters off the states of Washington and California, from the central North Atlantic and northeast Pacific Oceans, and from Chesapeake Bay. Total abundances of ammonium oxidizers ranged from 10⁷ cells 1^-1 in Chesapeake Bay and 10⁵ cells 1^-1 in inshore ocean waters to 10³ to 10⁴ cells 1^-1 in the open ocean. A potential nitrification rate was calculated. Microbial nitrification rates in the water column can be substantial and may be sufficient to balance the annual new production demand for nitrate.-from Author