Terrestrial environmental conditions during the Last Interstadial based on analysis of aquatic invertebrate communities from coastal exposures at the Dmitry Laptev Strait

Abstract

For the first time, data on the composition of cladoceran communities in lake bottom sediments from Bol’shoy Lyakhovsky Island and Oyogos Yar on the coast of the Dmitry Laptev Strait during the last major interglacial period (MIS 5e, 124-119 thousand years ago) have been obtained. 13 Cladocera taxa were identified in the composition of the taphocenoses. The composition of the Cladocera taphocenoses of Oyogos Yar indicates the presence of a well-developed littoral zone in the paleolakes, as most of the cladoceran remains belong to littoral-phytophilic taxa closely associated with macrophytes. In the Cladocera communities of Oyogos Yar, both cold-water representatives and more southern thermophilic taxa, such as Leydigia leydigi, were found. The findings of Cladocera remains from the MIS 5e period on the coast of the Laptev Sea, significantly north of their current ranges, allow for the reconstruction of warmer climatic conditions than those of today. The data obtained on Cladocera are well consistent with the results of chironomid analysis.