3.2. Examination of the biological material<br>3.2.1. Foraminiferal species<br>Samples of 100 cm3 volume were taken from the uppermost<br>sediment layer (thickness about 1 cm), and kept in an ethanol solution<br>of Rose Bengal (1 g/1000 ml ethanol). The function of Rose<br>Bengal was to stain the protoplasm of living Foraminifera (Walton,<br>1952), and the function of ethanol was to prevent any attack by<br>bacteria.<br>In the laboratory, the sediment was washed through a 63-lm<br>sieve to remove silt and clay, and dried in an oven at 60 C. The coarser<br>residue was then poured over ethyl carbon trichloride (C2HCl3).<br>The shells of Foraminifera, being lighter than C2HCl3, rose to the surface<br>while the heavier fraction settled on the bottom (Boltovskoym,<br>1965). The foraminiferal float was then separated from C2HCl3 by<br>decantation on a filter paper. After this separation, splitting of samples<br>and sorting of the biological material were carried out using a<br>dry micro splitter (model from Green Geological Services). The sample<br>was split into four subsamples and the taxa were counted for one<br>of the parts and then multiplied for 4. All specimens were counted<br>when the number of foraminifers in a sample was less than 50.<br>The foraminiferal species were transferred with a brush to special<br>slides with a black background. The living species were then identified<br>and counted under a Zeiss Stemi SV11 stereomicroscope. These<br>identifications were based principally on Cushman (1950), Loeblich<br>and Tappan (1988), and Boltovskoy et al. (1980), but various other<br>references, including Zaninetti et al. (1977), Brönnimann (1978,<br>1979, 1980), and Buzas et al. (1985) were also consulted. The
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