Population Dynamics of Bacterioplanktonic Component Associated with the Phytoplankton Biomass in Kongsfjorden, an Arctic Fjord

Temporal variation (June and October 2012) in bacterial and phytoplankton communities of Kongsfjorden was studied using 16S rRNA gene clone libraries and marker pigments respectively. Proteobacteria was the dominant phyla in Kongsfjorden with Gammaproteobacteria (42%) and Alphaproteobacteria (84%) dominating in June and October, respectively. Retrieval of sequences affiliated to Verrucomicrobia, Gammaproteobacteria and Bacteroidetes in June corresponded with high autotrophic biomass (Chl α, 33 ng l^–1) whereas abundance of SAR 11 coincided with decrease in the intensity of autotrophic biomass (Chl α, 24 ng l^–1) in October. Thus, the distribution of bacterioplankton community varied with change in phytoplankton composition indicating a significant coupling between these two groups in the fjord water.