The effect of inter-annual Atlantic water inflow variability on the planktonic protist community structure in the West Spitsbergen waters during the summer
We investigated the spatial and inter-annual variations in planktonic protist community taxonomic composition with respect to size and trophic structure in the West Spitsbergen waters during the 2007, 2009 and 2010 summers. The protist communities were studied along a longitudinal transect from Kong...
Published in: | Journal of Plankton Research |
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Main Authors: | , , |
Format: | Text |
Language: | English |
Published: |
Oxford University Press
2014
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Subjects: | |
Online Access: | http://plankt.oxfordjournals.org/cgi/content/short/fbu044v1 https://doi.org/10.1093/plankt/fbu044 |
Summary: | We investigated the spatial and inter-annual variations in planktonic protist community taxonomic composition with respect to size and trophic structure in the West Spitsbergen waters during the 2007, 2009 and 2010 summers. The protist communities were studied along a longitudinal transect from Kongsfjorden through the shelf to open sea waters. Our investigation was conducted on the Atlantic water inflow, which varied between the years. We observed a weakening trend in the northward advection of warm, Atlantic water in the Eastern branch of the Fram Strait, which was confirmed by long-term satellite-derived sea surface temperature (SST) measurements. The changing hydrological regime affected the summer protist taxonomic composition, abundance and biomass. These communities were numerically dominated by nanoplanktonic phototrophs, primarily cryptophytes. The microplanktonic heterotrophs (ciliates and dinoflagellates) were the major contributors to biomass, especially during the warmest year, 2007. Compared with previous investigations conducted in colder years, we observed a lower relative contribution of diatoms to the total protist biomass. Our results indicate that differences in the strength of Atlantic water inflow may have consequences for the composition of the plankton community in Kongsfjorden and the adjacent Eastern Fram Strait. |
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