Phytoplankton chemotaxonomy in waters around the Svalbard archipelago reveals high amounts of Chi b and presence of gyroxanthin-diester

摘要

Phytoplankton pigment signatures from a cruise in 2005 are herein presented and used as a chemo-taxonomic tool for phytoplankton diversity in the Svalbard marine archipelago. Studies from these waters have until recently reported only a few groups of phytoplankton, and while this paper is the first to show that the diversity around Svalbard includes all major phytoplankton pigment groups, the results are seen in relation to other similar studies from the Arctic. We present two potentially important marker pigments: prasinoxanthin, originating from prasinophytes, and gyroxanthin-diester, possibly originating from the temperate- and bloom-forming coccolithophore Emiliania huxleyi. Pigment identification by HPLC revealed a significant amount of Chlorophyll b-containing chlorophyceae, euglenophyceae and prasinophyceae. Prasinoxanthin was present at 50% of the examined stations, typically at Chi a maximum (15-25 m depth), in both Atlantic and Arctic water masses. Gyroxanthin-diester, in contrast to prasinoxanthin, was found only in Atlantic water masses and at low concentrations. Our data may be important for the identification and verification of remotely sensed images of different pigment groups of phytoplankton and their corresponding biomass, typically estimated from Chi a. Remotely sensed presence of coccoliths, indicating E. huxleyi at sea surface, is discussed in relation to water masses and pigment signatures at sea surface and Chi a maximum depths.