Distribution of organic-walled dinoflagellate cysts in surface sediments from transects across the Polar Front offshore southeast Greenland

The Polar Front along the southeast Greenland Margin denotes the contrastin g hydrographic properties of the polar and Atlantic water masses on either side. The remains of planktonic organisms in underlying sediments are expec ted to reflect these contrasts. To test this, we quantitatively analysed th e organic-walled dinoflagellate cyst (dinocyst) assemblages in surface sedi ments from transects across the present-day Polar Front on the southeast Gr eenland Margin. Proportional differences are found between the composition of the dinocyst assemblages on either side of the Polar Front. The influence of polar water can be traced in the dinocyst record as high abundances of Algidasphaeridi um? minutum and the presence of Pentapharsodinium dalei. The influence of A tlantic water is reflected in the presence of Operculodinium centrocarpum a nd Selenopemphix quanta. All samples include taxa from both environments, b ut the quantitative composition of the cyst assemblages clearly reflects th e hydrographic features of the overlying surface water masses. Copyright (C ) 2001 John Wiley & Sons, Ltd.