Summary: | Buried pond sediments at the Kilgii Gwaay archaeological site on Ellen Island in Gwaii Haanas National Park, were analyzed palynologically to produce a high-resolution record of postglacial vegetation during late glacial and early Holocene time. Seven AMS radiocarbon dates provide a sediment core chronology spanning the period 14,470-10,870 cal yr BP. Four biostratigraphic zones are defined, with a transition from early herb-shrub tundra (14,510 cal yr BP) to a Pinus-dominated forest 14,000 cal yr BP. Pinus is largely replaced by Picea 13,290 cal yr BP, followed by establishment of Tsuga heterophylla 12,420 cal yr BP. Changes in vegetation assemblages and stratigraphy may indicate cooling associated with the Younger Dryas event. Charcoal analysis reveal peak abundance during the known occupation of Kilgii Gwaay (10,700 cal yr BP). Charcoal extends below the known occupation horizon, indicating human presence as early as 11,500 cal yr BP, approximately 800 years earlier than previously documented.
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