| Summary: | Maintenance and Update Frequency: notPlanned Statement: Foraminifera were identified accurately to a species level, with an average of 436 individuals picked and identified per sample. Relative species abundances are calculated as a percentage of the total count. Parameters: Age of core (yrs BP), relative abundance of planktonic foraminifera assemblages (%). Statement: Counts of planktonic foraminifera were made on splits of the >150µm fractions to provide a base level for ecological counts, removing small juvenile and possibly unidentifiable foraminifera. Each sample was split by an Otto-micro splitter until ~400 species were present in the final split. Credit The Australian National University (ANU) Credit Funded by The National Oceans Office (NOO) Credit Funded by The French Polar Institute Credit Funded by The Australian Research Council (ARC) Credit Funded by The Australian Institute of Nuclear Science Engineering (AINSE) Credit Funded by The Murray Darling Basin Commission Purpose To reconstruct the faunal assemblages of planktonic foraminifera through time and to give insight into the palaeoceanography of the core location. The advent of deep-sea drilling in the 1950's prompted the use of planktonic foraminifera (unicellular protozans) as palaeoceanographic indicators. They provide a natural archive of past environmental changes due to their global distribution, their prolific productivity and sensitivity to environmental variations. The most abundant species within core MD002361 is the subtropical species Gs. ruber. High abundances =30% are seen during the interglacial periods Marine Isotope Stages (MIS) 11, 9, 7, 5 with peak abundance (37.7%) during the Holocene. Other tropical and subtropical species follow this pattern. The transitional, deep dwelling species Gr. inflata has the most distinct abundance change within core MD002361. This species is absent during the interglacial periods but achieves high relative abundances (~20-30%) during glacial periods.
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