Figure 3.
Microbial community structures determined by Illumina sequencing (>105 reads per sample) of 16S-V6 rRNA amplicons obtained from surface and deep samples at sites with dense ice cover at the shelf break (Shelf), inside the Amundsen Sea polynya and in open waters adjacent to the Dotson glacier (Dotson) during a Phaeocystis antarctica bloom in 2010–2011. (A) (top) denotes the concentration of extracted DNA for each sample as a proxy for microbial biomass; the “★” symbols denote deep (>350 m) samples. The relative contribution of Bacteria vs. Eukaryota (chloroplast 16S) is presented in (B). (C,D) present the phytoplankton and bacterioplankton community composition at the phylum level.