In the Laptev and Kara seas modern ostracod assemblages replace each other with depth and increasing distance from the coast (estuarine, inner-shelf, middle-shelf, outer-shelf, upper continental slope). The same happens with fossil assemblages of all studied cores during the Postglacial transgression. Five out of six distinguished fossil assemblages have modern analogs and are easy to trace in time and space. The deglacial assemblage of the upper continental slope stands out as a specific community dominated by arctic, North Atlantic and euryhaline species, indicating inflows of Atlantic-derived waters and downslope sand slides due to the proximity of the paleocoastline. Assemblages are taxonomically stable, but are characterized by minor taxonomic variety due to ostracod sensitivity to environmental changes.
Diversity-abundance correlation shows that near-shore and freshwater environments are less stable than those from the deeper shelf and upper continental slope, since Arctic shelves are shallow and can not be compared to real deep-water dynamic environments. In the Kara and Laptev seas abundance diminishes with depth and distance from the coast, while taxonomic diversity increases.