| Summary: | Maintenance and Update Frequency: notPlanned Statement: Foraminifera were identified accurately to a species level, with an average of 429 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 Australian Research Council (ARC) Credit Funded by The French Polar Institute 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 highest species abundance of foraminifera in core MD032607 was recorded by Globigerina bulloides (~45%) during the penultimate glacial period (MIS 6) and, generally, was the most abundant with an average abundance of 19.5%. The dominance of the sub-polar, transitional species, Ga. bulloides in this core suggests the influence of cold, nutrient-rich water during certain isotopic stages. Conversely, the dominant warm and oligotrophic species Globigerinoides ruber recorded its lowest abundance in Marine Isotope Stage (MIS) 6, and is totally removed from ...
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