Изменения растительных сообществ арктической Чукотки в изотопные стадии 40-49

Abstract

The palynological record from Lake El'gygytgyn, spanning the interval between c. 1.286 and 1.492 million years ago, shows repeated changes in plant communities in Arctic Chukotka, which reflect variations in glacial, interstadial, and interglacial climatic conditions. Thirteen pollen zones were defined, corresponding to marine oxygen isotope stages 40-49. The consistent presence of Larix pollen in these pollen spectra indicates that even under extremely severe climatic conditions that occurred in areas of the Anadyr plateau and Lake El'gygytgyn during the Calabrian Age, larch forest-tundra survived. The continued presence of forest habitats differs sharply from the herb- dominated tundra that characterized many glacial intervals in the Arctic during the Middle and Late Pleisto?ene. The warmest climate within the 1.286-1.492 million year interval, seen in pollen zone 9, appeared during isotope stage 43. The maximum in cold conditions occurred during the second half of isotope stage 44 (pollen zone 8).