Relative abundance of diatom species in surface samples from the Southern Ocean, major open ocean species, supplement to: Crosta, Xavier; Romero, Oscar E; Armand, Leanne K; Pichon, Jean-Jacques (2005): The biogeography of major diatom taxa in Southern Ocean sediments: 2. Open ocean related species. Palaeogeography, Palaeoclimatology, Palaeoecology, 223(1-2), 66-92


Diatom assemblages from 228 core-top samples were investigated to determine the modern geographic distributions of 10 major open ocean species or species groups in the Atlantic and Indian sectors of the Southern Ocean. Our study gives a more comprehensive view of the relationships between diatom distribution and environmental pressures than previous studies, as our modern database covers a much wider area, and additionally highlights the relationships with sea ice cover and concentration. The 10 species or species categories can mainly be lumped into three groupings. First, a cool open ocean grouping composed of Rhizosolenia pointed group, Thalassiosira gracilis group and Trichotoxon reinboldii with maximum relative abundances occurring within the maximum winter sea-ice edge. Second, a pelagic open ocean grouping composed of Fragilariopsis kerguelensis, Thalassiosira lentiginosa, Thalassiosira oliverana and Thalassiothrix spp. group with maximum occurrences at the Antarctic Polar Front. Third, a warm open ocean grouping with maximum abundances observed within the Polar Front Zone and composed of the Rhizosolenia rounded group, the Thalassionema nitzschioides var. nitzschioides group and the Thalassionema nitzschioides var. lanceolata. Comparisons of the abovementioned 10 species or species groups with modern February sea-surface temperatures and sea-ice duration and concentration reveal species-specific sedimentary distributions regulated both by sea-surface temperatures and sea ice conditions that support the use of diatom remains to reconstruct past variations of these environmental parameters via qualitative and transfer function approaches.

Depth=Surface sediment 0-1 cm

Related Identifier
Metadata Access
Creator Crosta, Xavier; Romero, Oscar E; Armand, Leanne K; Pichon, Jean-Jacques
Publisher PANGAEA - Data Publisher for Earth & Environmental Science
Publication Year 2005
Rights Creative Commons Attribution 3.0 Unported;
OpenAccess true
Language English
Resource Type Supplementary Dataset
Format text/tab-separated-values
Size 216 data points
Discipline Earth System Research
Spatial Coverage (-24.248W, -44.517S, -17.340E, -31.950N); Central South Atlantic
Temporal Coverage Begin 2000-02-17T05:54:00Z
Temporal Coverage End 2000-03-04T02:21:00Z