Vegetation dynamics, paleoecology, and climate change during the Quaternary and Paleogene of Western Canada

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The long-term goal of my research program is to reconstruct past environmental changes and their impacts on ecosystems, including human populations in British Columbia. Information provided by our published research has been used by foresters, park managers, educators, natural hazards planners, researchers and others to understand the present state of our environment, and to plan for possible future changes. The distant past can be a reliable predictor of what might happen again, and is an important component of planning for the future. Over the next funding cycle we will address the following four short-term objectives. In Objective 1 we will investigate one of the most dramatic global climatic changes of the last 11,000 years, called "The Holocene Turnover" 4,200 years ago. This climate change caused megadroughts and contributed to the collapse of ancient civilizations in the Mediterranean region and elsewhere. We plan to sample, date and analyze peat deposits at high resolution on Haida Gwaii to test the hypothesis that this event also affected Western Canada, as suggested by preliminary evidence. In Objective 2 we will continue our research on the environmental history and plant biogeography of Haida Gwaii, with a focus on the last glaciation and an earlier glaciation about 57,000 years ago. The mystery of glacial refugia for plants and animals during ice age events is an area of active research. Our fossil evidence from sea-cliffs at Cape Ball indicates that some plant species survived the last two glaciations up to the present day. A second site that might confirm this pattern has been identified at sea-cliffs at Mary Point, and we propose to conduct a parallel investigation there. In Objective 3, we will extend our Eocene paleoenvironmental research using fossil plants and insects from the Okanagan Highlands of BC, one of the richest fossil areas in the world for the period of 50-53 million years ago. This "Early Eocene Climatic Optimum" followed a rapid warming event at the end of the Paleocene 56 million years ago that was followed by the hot Eocene "Greenhouse World", a period of very high biodiversity where many plants and insects diversified. In continued collaboration with Dr. S.B. Archibald, an expert on fossil insects, we plan to conduct a detailed and unbiased fossil excavation at the Quilchena, BC locality, to determine the effects of a warming climate on an ancient biotic community, for comparison with similar studies at other localities. In Objective 4, we will investigate the first mid-Paleocene plant megafossil locality BC at Kanaka Creek. It documents forest composition and climate prior to the drastically altered forest of the late Paleocene 56 million year ago due to rapid warming, that is also seen in the warm Early Eocene that follows. The fossils in my lab at SFU need to be combined with a large collection at the Geological Survey of Canada in Ottawa to further refine the climatic interpretation and plant diversity.