Vernet Lab

The Ecology of

Polar Phytoplankton

Dr. Maria Vernet
Integrative Oceanography Division
Room 2123, Sverdrup Hall
Phone: (858) 534-5322
Fax: (858) 822-0562

February 17, 2018 | Not Logged In (public login | local login)

§ Research Projects » Small Phytoplankton

Small might not mean less: Phytoplankton cell size and carbon cycling in polar waters (1 February 2015 – Present) – Principal Investigator: Maria Vernet, University of California-San Diego Scripps Inst of Oceanography.
Funded by Hanse-Wissenschaftskolleg (HWK), Delmenhorst, Lower Saxony, Germany

ABSTRACT: Sedimentation of particulate organic matter to depth is crucial to carbon sequestration from the surface of the ocean and balancing anthropogenic carbon dioxide in the atmosphere. The existing paradigm of large cells as the main contributors to sedimentation, mainly by direct cell sinking or through herbivore fecal pellets, has been challenged by data and modeling (Richardson and Jackson, Science 315: 838, 2007). Determining the role that small cells play in sedimentation is crucial in our times, with increasing abundance of small cells in polar waters as a consequence of climate change. As a large proportion of the world’s fisheries depend on high-latitude carbon, we will test the hypothesis that small cells do not inhibit sedimentation by two approaches: first, a critical review of the literature to establish if present understanding is based on facts; second, by testing the role of polar food webs on the relationship between phytoplankton cell size and carbon sedimentation, in collaboration with the modeler T. Richardson (op.cit.). A multidisciplinary team of AWI scientists from Biosciences and Climate Sciences, Dr. Ilka Peeken and Dr. Mario Hoppema, will provide insight, data for the models and critical review of results. In this way, we will publish an authoritative report on the relationship between cell size and organic carbon sedimentation, with new insights on the role of polar food web structure on carbon cycling.