![]() ![]() The observed trends are enhanced by the onset of rhodophyte photosynthesis in the rhodolith beds during the polar day upon retreat of sea-ice. Backed up by seawater stable carbon and oxygen isotope signatures, this is interpreted as an effect of limited air-sea gas exchange during seasonal ice cover in combination with a boost in community photosynthesis during the spring phytoplankton bloom. Accordingly, oxygen levels were found elevated and carbon dioxide concentrations ( pCO 2) markedly reduced, on average only half the expected equilibrium values. This indicates that a recycling system was fuelling primary production after the phytoplankton spring bloom at the time of sampling in June 2016. At both sites, dissolved inorganic nutrients in the water column were found depleted (except for elevated ammonium concentrations) and show an overall increase in concentration and N:P ratios toward deeper waters. Repetitive CTD profiling in concert with autonomous temperature/salinity loggers on a long-term settlement platform identified spatiotemporal patterns in the involved Atlantic and Polar water masses, whereas short-term deployments of a lander revealed fluctuations of environmental variables in the rhodolith beds in Mosselbukta and at same depth (46 m) at Bjørnøy-Banken. By integrating data from physical oceanography, marine biology, and marine geology, the present contribution characterises the environmental setting and biosedimentary dynamics of these two polar carbonate factories. Two contrasting sites of intense biogenic carbonate production, the rhodolith beds in Mosselbukta in the north of the archipelago and the barnacle-mollusc dominated carbonate sediments accumulating in the strong hydrodynamic regime of the Bjørnøy-Banken south of Spitsbergen, were the targets of the RV Maria S. The Arctic Svalbard Archipelago hosts the world’s northernmost cold-water ‘carbonate factories’ thriving here despite of presumably unfavourable environmental conditions and extreme seasonality. 5Institute of Geosciences, Goethe University Frankfurt, Frankfurt, Germany.4Technology & Logistics Centre, GEOMAR – Helmholtz Centre for Ocean Research, Kiel, Germany.3Research Division 2: Marine Biogeochemistry, GEOMAR – Helmholtz Centre for Ocean Research, Kiel, Germany.2Department of Geosciences, University of Fribourg, Fribourg, Switzerland.1Marine Research Department, Senckenberg am Meer, Wilhelmshaven, Germany.Büscher 3, Peter Linke 4 and Jacek Raddatz 5 Lowest Pressure 872.Max Wisshak 1*, Hermann Neumann 1, Andres Rüggeberg 2, Janina V.Highest Pressure 1035.9 hPa Salida - Monarch Pass, CO.Most Humid 101.49% Utopia Creek, Indian Mountain LRRS Airport, AK.Wettest (Last Hour) 1in Mena, Mena Intermountain Municipal Airport, AR.Recorded at Tacoma, Tacoma Narrows Airport Updated 1 hour 43 mins ago (8.5 miles away) Get an account to remove ads View More Real-Time Extremes Nation State County 4.6mph ENE Speed and Direction Strength Light Trend Increasing ![]()
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