Anaerobic ammonium oxidation (anammox) is a type of biological oxidation mediated by a group of Planctomycete-like bacteria. Members of the genus “Candidatus Scalindua” are mainly found in marine environments, but not exclusively. This group is cultured using different inoculums and conditions; however, its optimal growth conditions are not clear. Additionally, little is known about the factors that influence on the activity and the selection of population of marine anammox bacteria. This study was conducted to investigate the influence of temperature and salinity on the marine anammox community. To accomplish this, an up-flow fixed-bed column reactor was operated, and quantitative FISH with probes specific to dominant marine anammox bacteria was conducted. Anammox activity was observed at 20 and 30°C, but not at 10°C. A nitrogen removal rate of 0.32 kg TN m-3 day-1 was obtained at 20°C. These results suggest that temperature affects the activity (nitrogen removal rate) of anammox bacteria, while salinity does not affect the activity in the marine anammox biofilm.

This study was partially supported by an Assistance for Research and Development of Construction Technology grant from the Ministry of Land, Infrastructure, Transport and Tourism, a Grant-in-Aid for Scientific Research (C) from the Ministry of Education, Culture, Sports, Science and Technology, research foundations from the Institute for Fermentation (IFO), Osaka, and research foundations from the Public Association for Construction Service in the Chugoku region.