The ongoing project dealing with the Late Quaternary interstadial and interglacial periods in the Eurasian Arctic aims to reconstruct environmental history of the region based of microfossil remains from permafrost sequences of NE Siberia. In this poster I present newly obtained results of pollen and testate amoebae analyses. My study is focused on three following topics: 1. Pleistocene and Early Holocene vegetation and climate history in the Verkhoyansk Mountains (Yakutia, Russia) derived from pollen recordsThe pollen spectra from the P12 section located near the Tumara river (63°N, 130°E) shows that open tundra- and steppe-like Poaceae and Cyperaceae associations with some other herbs like Caryophyllaceae, Asteraceae, Ranunculaceae dominated the area for nearly the last 50 14C kyr. Steppe-like communities with Artemisia, Cichoriaceae, Thalictrum existed. Shrubby tundra communities with Salix and Betula sect. Nanae reflect the existence of relatively wet habitats during this relatively warm period (Karginsky Interstadial). Attention has to be paid to the lower part of this section. Samples were dated up to 220 14C kyr BP possibly representing the Eemian Interglacial with increasing numbers of tree pollen (PZ II-III).2. Testate Amoebae as palaeoenvironmental indicators in quaternary sediments from Cape Mamontovy Klyk, Laptev Sea, RussiaInvestigated samples from the Cape Mamontovy Klyk (73°N, 116°E) at the Laptev Sea coast are covering the last 50 14C kyr. The main characteristic of the Mamontovy Klyk fossil rhizopod complexes is the dominance of eurybiotic soil genera, including Centropyxis, Cyclopyxis, Plagiopyxis and Phryganella. These genera have a wide tolerance to changes of environmental conditions. They also reflect soil conditions rather similar to the modern arctic tundra environment, especially for the period 40-50 14C kyr BP (Karginsky Interstadial). During the interval between 30-10 14C kyr BP species diversity and density decreased and some testate amoebae completely disappeared, indicating the harsh environments of the Sartan stadial period.3. Palaeoenvironmental reconstructions in the Central Verkhoyansk Mountains: pollen record from Lake Billyakh, RussiaThe study at Lake Billyakh (65°N, 120°E; 340m a.s.l.) in April 2005 was stimulated through foregoing Russian-German expeditions in the Central Verkhoyansk Mountains in 2002/2003. This area is characterized by extreme continental climate conditions and coldest winter temperatures (Oimjakon Cold Pole of the Northern Hemisphere). Permafrost layer is continuous and northern larch (Larix dahurica) taiga dominates the vegetation. First radiocarbon dates indicates a Holocene age for the upper sediment section (2m). The lower part is older than 25 kyr. First examined Holocene samples show high pollen concentrations and taxa diversity, especially for NAP, suggesting a high potential of the lake sediment for the reconstruction of the late Pleistocene and Holocene environmental history of this so far poorly studied region.