Synechococcus in the Atlantic Gateway to the Arctic Ocean

摘要: Increasing temperatures, with pronounced effects at high latitudes, have raised questions about potential changes in species composition, as well possible increased importance of small-celled phytoplankton marine systems. In this study, we mapped out one the smallest and globally most widespread primary producers, picocyanobacterium Synechococcus, within Atlantic inflow to Arctic Ocean. contrast general understanding that Synechococcus is almost absent polar oceans due low encountered abundances (up 21,000 cells mL-1) 79 °N, documented their presence far north 82.5 °N. Covering an annual cycle 2014, found during autumn winter, was often more abundant than picoeukaryotes, which usually dominate picophytoplankton communities Arctic. community composition shifted from a quite genetic diversity spring bloom clear dominance two specific operational taxonomic units (OTUs) winter. We observed higher 1,000 mL-1 water colder 2 °C seven distinct stations size-fractionation experiments demonstrated net growth absence nano-sized grazers certain periods year. Phylogenetic analysis petB sequences these latitude group previously described cold-adapted clades I IV, but also contributed unveil novel diversity, especially clade I.