FN Archimer Export Format PT J TI Effect of particulate organic carbon on heterotrophic bacterial populations and nitrification efficiency in biological filters BT AF MICHAUD, Luigi BLANCHETON, Jean-Paul BRUNI, V PIEDRAHITA, Raul AS 1:1,2;2:1;3:2;4:1,3; FF 1:PDG-DOP-DCM-PM-APOI;2:PDG-DOP-DCM-PM-APOI;3:;4:PDG-DOP-DCM-PM-APOI; C1 IFREMER, F-34250 Palavas Les Flots, France. Univ Messina, Dept Anim Biol & Marine Ecol, I-98166 Messina, Italy. Univ Calif Davis, Dept Biol & Agr Engn, Davis, CA 95616 USA. C2 IFREMER, FRANCE UNIV MESSINA, ITALY UNIV CALIF DAVIS, USA SI PALAVAS SE PDG-DOP-DCM-PM-APOI IN WOS Ifremer jusqu'en 2018 copubli-europe copubli-int-hors-europe IF 1.026 TC 159 UR https://archimer.ifremer.fr/doc/2006/publication-1553.pdf LA English DT Article DE ;Recirculating aquaculture system;Particulate organic matter;Heterotrophic bacteria;Nitrification AB Competition between heterotrophic and nitrifying bacteria is of major practical importance in aquaculture biofilter design and operation. This competition must be understood to minimize the negative impact of heterotrophic bacteria on an aquaculture system. On the other hand, the heterotrophic population is suspected of having a positive effect against pathogenic bacteria. Little information is available on the bacterial communities present within aquaculture systems, except for nitrifying bacteria, but a combination of traditional aquacultural engineering research methods and novel microbiological techniques offers new opportunities for the study of these communities. The heterotrophic bacterial population activity and the nitrification efficiency of a submerged biological filter were studied for an influent TAN concentration of 2 mg/A and varying C/N ratios. The TAN removal rate was found to be 30% lower at a C/N ratio of 0.5 than at a C/N ratio of 0. For higher C/N ratios the reduction in nitfification efficiency was 50% while the attached bacterial abundance was doubled. Moreover, results confirm that abundance of sheared and attached bacteria are correlated. It is not known to what extent biofilter configuration might influence the relationship between heterotrophic and nitrifying bacteria, and further work will be carried out with moving bed and fluidized filters. A better understanding of the role of the heterotrophic bacteria in RAS will help to optimize any positive "biocontrol" effect and to minimize the microbial degradation of rearing water and the reduction of nitrification rates. PY 2006 PD MAY SO Aquacultural Engineering SN 0144-8609 PU Elsevier VL 34 IS 3 UT 000237230600009 BP 224 EP 233 DI 10.1016/j.aquaeng.2005.07.005 ID 1553 ER EF