Marine Picoeukaryotes in Cold Water:Diversity and Ecology

• Main Author: Sørensen, Nikolaj
• Format: Book
• Language: English
• Published: Natural History Museum of Denmark, Faculty of Science, University of Copenhagen 2014
• Subjects: Arctic; Greenland; Climate change; Global warming; Sea ice
• Online Access: https://curis.ku.dk/portal/da/publications/marine-picoeukaryotes-in-cold-water(7b2cb836-7950-4e78-bffe-f690a5a83d54).html; https://soeg.kb.dk/permalink/45KBDK_KGL/fbp0ps/alma99122516291105763

Picoeukaryotes form an important part of marine ecosystems, both as primary producers, bacterial grazers and parasites. The Arctic is experiencing accelerated global warming and picoeukaryotes may thus be considered to be at the forefront of climate change. This PhD thesis sets out to investigate picoeukaryotes in the Arctic. The objective is two fold: improve and expand upon current methods used for investigating picoeukaryotes and investigate the diversity, ecology, population dynamics and biogeography of Arctic picoeukaryotes. The hypotheses that extracellular DNA can introduce artefacts in molecular studies using serial filtration for size fractioning and that haptophytes are underrepresented in molecular studies as a result of their high GC content are tested. A novel 18S rDNA sequencing protocol, using Ion Torrent PGM, is also presented. The population dynamics and succession of picophytoplankton during an Arctic spring bloom is investigated together with the diversity, ecology and biogeography of the picoeukaryotic community east of Greenland. Finally, the first sequencing study of sea ice picoeukaryotes is presented, providing insights into this community’s ecology and dispersal.