Diversity and Selection of Surface Marine Microbiomes in the Atlantic-Influenced Arctic

• Published in: Frontiers in microbiology 2022-07, Vol.13, p.892634-892634
• Main Authors: Aalto, Nerea J., Schweitzer, Hannah D., Krsmanovic, Stina, Campbell, Karley, Bernstein, Hans C.
• Format: Article
• Language: English
• Subjects: Arctic Ocean; Atlantification; diatoms; Microbiology; null model; sea-ice; temperature
• ISSN: 1664-302X; 1664-302X
• DOI: 10.3389/fmicb.2022.892634

Arctic marine environments are experiencing rapid changes due to the polar amplification of global warming. These changes impact the habitat of the cold-adapted microbial communities, which underpin biogeochemical cycles and marine food webs. We comparatively investigated the differences in prokaryotic and microeukaryotic taxa between summer surface water microbiomes sampled along a latitudinal transect from the ice-free southern Barents Sea and into the sea-ice-covered Nansen Basin to disentangle the dominating community (ecological) selection processes driving phylogenetic diversity. The community structure and richness of each site-specific microbiome were assessed in relation to the physical and biogeochemical conditions of the environment. A strong homogeneous deterministic selection process was inferred across the entire sampling transect via a phylogenetic null modeling approach. The microbial species richness and diversity were not negatively influenced by northward decreasing temperature and salinity. The results also suggest that regional phytoplankton blooms are a major prevalent factor in governing the bacterial community structure. This study supports the consideration that strong homogeneous selection is imposed across these cold-water marine environments uniformly, regardless of geographic assignments within either the Nansen Basin or the Barents Sea.