Water masses influence bacterioplankton community structure in summer Kongsfjorden.

To ascertain the saying "Everything is everywhere, but the environment selects", it was imperative to find out the main factor influencing bacterioplankton composition at genus level of Kongsfjorden where was influenced both by glacier melting water and Atlantic water. Thus, bacterioplankton diversity was investigated using pyrosequencing. In addition, nutrients, chlorophyll a, in situ temperature and salinity were measured. There were seventeen of 33 identified genera with relative abundance > 0.1%. Redundancy analysis showed that 73.02% of bacterioplankton community variance could be explained by environmental parameters. Furthermore, most of the abundant genera demonstrated significant correlation with environment parameters revealed by correlation analysis. Moreover, phosphate, nitrate and Chl a concentration, and the abundance of top nine identified genera varied with water mass significantly as shown by analysis of variance. Our results supported the notion that environmental factors, especially water mass had significant effect on bacterioplankton distribution at genus level. Considering the high sensitivity to environmental change and low error rate in identification, bacterioplankton at genus level could be potential bio-markers for monitoring environmental changes.