The Arctic frontiers is held digitally this year. Researchers from the Nansen Legacy project participated with digital booths and presented their work in a digital booth.Â
Here are a short summaries of the digital booths at Arctic Frontiers 2021:Â
Emmelie Åström (UiT):
Trophic relationships, carbon sources and food-web patterns in Barents Sea benthos.
Depleted δ13C signatures in some benthic taxa indicate significant input of chemosynthesis-based carbon (CBC) into the food web
Large intra-species variation in isotope carbon and nitrogen signatures across geographical locations among several benthic taxa suggests opportunistic diets and wide trophic niches
Chemosynthesis based carbon add a supplementary energy source to the Svalbard-Barents Sea food web, decoupled from seasonal phytoplankton driven production.
Zoe Koenig (UiB):
Structure and drivers of ocean mixing north of Svalbard in summer and fall 2018.
Estimates of vertical turbulent heat flux from the Atlantic Water layer up to the mixed layer is on average 8 W m−2 , accounting for ∼1% of the total heat loss of the Atlantic layer north of Svalbard
Summer melting of sea ice reduces the temperature, salinity and depth of the mixed layer, and increases salt and buoyancy fluxes at the base of the mixed layer
Deeper in the water column and near the seabed, tidal work is a main source of turbulence.
Miriam Marquard (UiT):
First insight into seasonal dynamics of sympagic meiofauna composition and abundance in the changing Barents Sea (The Nansen Legacy)
The study gives first insight into seasonal dynamics of sea ice meiofauna in the northern Barents Sea
Predominance of benthic foraminifers within the Barents Sea sea ice in December
Ciliates occupy a major share of the sea ice habitat in winter and summer.
Libby Jones (HI):
Ocean acidification dynamics in the marginal ice zone of the Barents Sea
This study indicates that warming, sea ice loss and Atlantification may reduce acidification of the Barents Sea.
Libby Jones (HI):
Ocean acidification around the Svalbard archipelago and Atlantic Arctic Ocean.
Biological production dominates the inter-annual variability in calcium carbonate saturation and acidification states across the Svalbard and Atlantic Arctic region
Heavy sea ice years experienced lower biologically-driven increases in calcium carbonate saturation coupled to meltwater-suppression of calcium carbonate saturation
Incursions of Atlantic Water fuel biological production and supply carbonate ions to increase calcium carbonate saturation in productive, ice-free waters
Stephen Kohler (NTNU):
Seasonal scavenging of inorganic mercury in the Arctic Ocean during transition to polar night
The Arctic Ocean receives seasonal mercury inputs from both atmospheric and riverine sources during the productive summer months.
Mercury in surface waters is re-emitted back to the atmosphere by photoreduction or transported to depth with sinking particulate matter, where it is methylated to toxic methylmercury.
However, little is known about the seasonal cycling of mercury in the water column in the Arctic. Here we show, for the first time, polar night THg and MeHg concentrations on a meridional transect in the water column of the northern Barents Sea into the Nansen Basin.
We find a loss of inorganic mercury during the autumn transition to polar night. We suggest scavenging as the dominant removal process of mercury from surface waters in autumn, and recommend an updated seasonal evaluation of the Arctic mercury budget.
Konrad Karlsson (UNIS):
The metabolism of key Arctic zooplankton in the polar night – an ecological perspective
Metabolism is a fundamental estimate of biological activity and change through the key events of an organism’s life cycle, such as feeding, development and reproduction.
The foremost predictor of metabolism is biomass, and predicts that organisms of larger mass will respire relatively less than those of smaller mass, and hence, the turnover of energy and carbon by smaller organism is quicker than for larger ones. As climate change increase temperature in the Arctic, a borealization of the Arctic zooplankton community is possible, leading to an increasing amount of small sized southern species, and hence, a greater turnover of energy in Arctic ecosystems.
In the present study we investigated and compared the metabolism of five key Arctic copepod species during the polar night. Three of which were Calanus species, C. finmarchicus, C. glacialis, and C. hyperboreus, and ecologically similar although of different mass. The two other species were Metridia longa and Paraeuchaeta sp. two actively swimming copepods and ecologically distinct from Calanus, as both species feed actively during the polar night, whereas Calanus is typically dormant.
Our results show that metabolism is to a large degree affected by the organism’s life style, where species with high locomotive and feeding activity have higher metabolism than less active ones. This suggests that ecological differences take part in metabolic evolution, and that the rate of energy turnover in Arctic ecosystems is not only affected by the size of the species but their ecology as well.
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