The biogeography and ecology of common diatom species in the northern North Atlantic, and their implications for paleoceanographic reconstructions
|Author(s)||Oksman Mimmi1, 2, Juggins Stephen3, Miettinen Arto4, Witkowski Andrzej5, Weckstrom Kaarina6, 7|
|Affiliation(s)||1 : Univ Helsinki, Dept Geosci & Geog, Gustaf Hallstromin Katu 2a, FIN-00014 Helsinki, Finland.
2 : Aarhus Univ, Dept Geosci, Hoegh Guldbergs Gade 2, DK-8000 Aarhus C, Denmark.
3 : Newcastle Univ, Sch Geog Polit & Sociol, Newcastle Upon Tyne NE1 7RU, Tyne & Wear, England.
4 : Fram Ctr, Norwegian Polar Inst, Hjalmar Johansens Gate 14, N-9296 Tromso, Norway.
5 : Univ Szczecin, Palaeoceanol Unit, Nat Sci Res & Educ Ctr, Fac Geosci, Mickiewicza 16a, Szczecin, Poland.
6 : Univ Helsinki, Ecosyst & Environm Res Programme, ECRU, Viikinkaari 1, FIN-00014 Helsinki, Finland.
7 : Geol Survey Denmark & Greenland GEUS, Dept Glaciol & Climate, Oster Voldgade 10, DK-1350 Copenhagen, Denmark.
|Source||Marine Micropaleontology (0377-8398) (Elsevier Science Bv), 2019-04 , Vol. 148 , P. 1-28|
|WOS© Times Cited||9|
|Keyword(s)||Diatoms, Calibration dataset, Northern hemisphere, Sea surface temperature, Sea ice|
Sound knowledge of present-day diatom species and their environments is crucial when attempting to reconstruct past climate and environmental changes based on fossil assemblages. For the North Atlantic region, the biogeography and ecology of many diatom taxa that are used as indicator-species in paleoceanographic studies are still not well known. Using information contained in large diatom-environment calibration datasets can greatly increase our knowledge on diatom taxa and improve the accuracy of paleoenvironmental reconstructions. A diatom calibration dataset including 183 surface sediment samples from the northern North Atlantic was used to explore the distribution and ecology of 21 common Northern Hemisphere diatom taxa. We define the ecological responses of these species to April sea ice concentrations and August sea surface temperatures (aSSTs) using Huisman-Olff-Fresco (HOF)-response curves, provide distribution maps, temperature optima and ranges, and high-quality light microscope images. Based on the results, we find species clearly associated with cold, warm and temperate waters. All species have a statistically significant relationship with aSST, and 15 species with sea ice. Of these, Actinocyclus curvatulus, Fragilariopsis oceanica and Porosira glacialis are most abundant at high sea ice concentrations, whereas Coscinodiscus radiants, Shionodiscus oestrupii, Thalassionema nitzschioides, Thalassiosira angulata, Thalassiosira nordenskioeldii and Thalassiosira pacifica are associated with low sea ice concentrations/ice-free conditions. Interestingly, some species frequently used as sea ice indicators, such as Fragilariopsis cylindrus, show similar abundances at high and low sea ice concentrations with no statistically significant relationship to sea ice.