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Seminar: Primary producers in a landfast ice-covered marine ecosystem of the central Canadian Arctic Archipelago

Speaker: Assistant Professor CJ Mundy, Centre for Earth Observation Science (CEOS), University of Manitoba, Canada

Info about event

Time

Tuesday 21 May 2013,  at 16:00 - 16:00

Location

ARC, C.F. Møllers Allé 8, 8000 Aarhus C, 1110-214

Organizer

ARC

Abstract

The Canadian Arctic Archipelago encompasses more than 50% of Canada’s Arctic shelf waters, but overall primary production and its biogeochemical role in the marine ecosystem are still poorly understood. For example, ice algae have been assumed to be the sole primary producers while the ocean is ice-covered, their contribution currently estimated at 5-10% annual production. However, we recently documented the occurrence of a significant under-ice phytoplankton bloom whose net production was a factor of magnitude more than that of ice algae. Documentation of this bloom occurred at a time when meltponds on the ice surface greatly increased the depth of the under-ice photic zone and water column stratification was influenced by ice melt. In this talk, I will provide a general background of the role of light and nutrients on primary production with a specific focus on ice-covered environments. In light of recent observations mentioned here, I will conclude with a newer "conceptual" view of the timing, magnitude and location of primary production in the central Canadian Arctic. Furthermore, I will discuss how this view could be related to a thinning ice cover and whether it may or may not apply to the rest of the Arctic.