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A new accerator mass spectrometry (AMS)‐dated sedimentary record from Lake Ochaul (54°14′N, 106°28′E; 641 m a.s.l.) in Eastern Siberia covers the interval from ca. 27 850 to 20 400 cal a bp at ca. 180‐year resolution and contributes to a better understanding of the complex spatial vegetation pattern during the Last Glacial Maximum (LGM). Non‐arboreal pollen taxa are abundant in the pollen assemblages (mean value ca. 92.6%), but boreal trees are represented by all major taxa that grow in the lake catchment today, including Betula sect. Albae (0.6–4.8%), Picea (0.6–2.8%), Pinus sibirica (Haploxylon type) (up to 1.5%), Pinus sylvestris (Diploxylon type) (up to 2%), Larix (up to 0.6%) and Abies (up to 0.6%). Betula sect. Nanae/Fruticosae (2–5.2%) and Salix (up to 3.2%) are the most representative boreal shrub taxa. Together with existing modern and fossil pollen data from the wider study region, the current record provides further evidence for the long‐debated presence of boreal trees and shrubs in Eastern Siberia throughout the LGM. Our results show that the Upper Lena was a region in which refugia for arboreal taxa existed and that far‐distant pollen transport can be ruled out as the source of the detected arboreal pollen.

The paper reports on the results of the pollen, plant macrofossil and geochemical analyses and the AMS 14 C-based chronology of the «Rüdersdorf» outcrop situated east of Berlin in Brandenburg (Germany). The postglacial landscape changed from an open one to generally forested by ca. 14 cal. kyr BP. Woody plants (mainly birch and pine) contributed up to 85% to the pollen assemblages ca. 13.4-12.5 cal. kyr BP. The subsequent Younger Dryas (YD) interval is characterized by a decrease in arboreal pollen (AP) to 75% but led neither to substantial deforestation nor spread of tundra vegetation. This supports the concept that the YD cooling was mainly limited to the winter months, while summers remained comparably warm and allowed much broader (than initially believed) spread of cold-tolerant boreal trees. Further support for this theory comes from the fact that the relatively low AP values persisted until ca. 10.6 cal. kyr BP, when the «hazel phase» of the regional vegetation succession began. The postglacial hunter-gatherer occupation is archaeologically confirmed in Brandenburg since ca. 13 cal. kyr BP, i.e. much later than in the western part of Germany and ca. 1000 years after the major amelioration in the Rüdersdorf environmental record.