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In the dark: a review of ecosystem processes during the Arctic polar night
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-08-28)
Several recent lines of evidence indicate that the polar night is key to understanding Arctic marine ecosystems. First, the polar night is not a period void of biological activity even though primary production is close to zero, but is rather characterized by a number of processes and interactions yet to be fully understood, including unanticipated high levels of feeding and reproduction in a ...
Is ambient light during the high Arctic polar night sufficient to act as a visual cue for zooplankton?
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-06-03)
The light regime is an ecologically important factor in pelagic habitats, influencing a range of biological processes. However, the availability and importance of light to these processes in high Arctic zooplankton communities during periods of 'complete' darkness (polar night) are poorly studied. Here we characterized the ambient light regime throughout the diel cycle during the high Arctic ...
From polar night to midnight sun: Diel vertical migration, metabolism and biogeochemical role of zooplankton in a high Arctic fjord (Kongsfjorden, Svalbard)
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-03-24)
Zooplankton vertical migration enhances the efficiency of the ocean biological pump by translocating carbon (C) and nitrogen (N) below the mixed layer through respiration and excretion at depth. We measured C and N active transport due to diel vertical migration (DVM) in a Svalbard fjord at 79°N. Multifrequency analysis of backscatter data from an Acoustic Zooplankton Fish Profiler moored from January ...
Seasonal and diel vertical migration of zooplankton in the High Arctic during the autumn midnight sun of 2008
(Journal article; Tidsskriftartikkel; Peer reviewed, 2011)
The diel vertical migration (DVM) of Calanus (Calanus finmarchicus, Calanus glacialis and Calanus hyperboreus) and Metridia longa was investigated in August 2008 at six locations to the north and northwest of Svalbard (Rijpfjorden, Ice, Marginal Ice Zone, Shelf break, Shelf and Kongsfjorden). Despite midnight sun conditions, a diel light cycle was clearly observed at all stations. We collected data ...
Use of an Autonomous Surface Vehicle reveals small-scale diel vertical migrations of zooplankton and susceptibility to light pollution under low solar irradiance
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-01-10)
Light is a major cue for nearly all life on Earth. However, most of our knowledge concerning the importance of light is based on organisms’ response to light during daytime, including the dusk and dawn phase. When it is dark, light is most often considered as pollution, with increasing appreciation of its negative ecological effects. Using an Autonomous Surface Vehicle fitted with a hyperspectral ...
Pelagic food-webs in a changing Arctic: a trait-based perspective suggests a mode of resilience
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-06-27)
Arctic marine ecosystems support fisheries of significant and increasing economic and nutritional value. Commercial stocks are sustained by pelagic food webs with relatively few keystone taxa mediating energy transfer to higher trophic levels, and it remains largely unknown how these taxa will be affected by changing climate and the influx of boreal taxa. <i>Calanus</i> species store large quantities ...