"Paleoecology of alpine tundra and high elevation plant communities, refugia and landscapes of British Columbia"

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Geological, botanical and DNA evidence indicate that parts of British Columbia may have escaped the last glaciation, a key feature of the biogeography of North America. This proposal tests the hypothesis that today's high elevation species, alpine plant communities and landscapes persisted through the last glacial maximum in the region and gave rise to modern alpine and sub-alpine flora and ecosystems. The project will use pollen and spore and other paleoecological analyses of sediments from lake cores and recently discovered geological exposures to trace the history of plants and ecosystems through the interval of maximum cold on south Vancouver Island and in the Omineca Mountains of north central British Columbia. Sedimentary sequences will be dated by radiocarbon and optical dating. In addition the reflected infrared to visible light spectrum of samples from soil horizons will be used in combination with remnant landform indicators of past frigid climates to differentiate land surfaces covered by the most recent ice sheet from those glaciated in a more distant time. The results will shed light on the origin and history of modern high altitude ecosystems and their sensitivity to climate change. They will help explain the distribution of modern plant species and their genetic types in western North America and their relationships to Beringia and Asia. They will provide insight in to whether or not there was a barrier to human and animal migrations into North America late in the Pleistocene Epoch. The project will help develop methods for distinguishing landscapes arising from recent glaciations of different ages.