Acta Adriatica, Vol. 58 No. 1, 2017.
Original scientific paper
https://doi.org/10.32582/aa.58.1.2
To what extent the size fraction affects an interpretation of planktonic foraminiferal assemblages - case study from Southern Adriatic
Krešimir MARKULIN
orcid.org/0000-0002-1503-8496
; Institute of Oceanography and Fisheries, Šetalište Ivana Meštrovića 63, 21000 Split, Croatia
Vlasta ĆOSOVIĆ
; Department of Geology, Faculty of Science, University of Zagreb, Horvatovac 102a, 10000 Zagreb, Croatia
Abstract
Study of planktonic foraminifera, sampled from two levels of a 26 cm thick core, recovered at 1,200 m water depth, sheds some lights on the composition of foraminiferal assemblages that occur
in the Southern Adriatic. Altogether 15 planktonic species (including one referred as undeterminable and two species recorded for the first time in the eastern Adriatic Sea) identified from 0-2 cm and
24-26 cm sediment intervals, were grouped into two assemblages: >63 μm fraction Turborotalita quinqueloba and >125 μm fraction as Globigerina bulloides-Globigerinoides ruber. The differences in core-top and core-bottom assemblages lie in: a) change in the relative proportion of some species; and b) slight differences in diversity indices. The relative proportions of species are strongly controlled by sieve mesh size, whereas the slight increase in diversity follows the increase in sieve mesh size. The benthic foraminifera, although constituting a negligible quantitative factor, show a slight increase in abundance and diversity of species with age.
Keywords
Adriatic Sea; planktonic foraminifera; size fraction; Turborotalita quinqueloba; Globigerina bulloides; Globigerinoides ruber; diversity indices
Hrčak ID:
185166
URI
Publication date:
26.6.2017.
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