Long-term responses of aquatic ecosystems to environmental change

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My NSERC research program will focus on polar aquatic ecosystems and their long-term responses to environmental change. My research team will place emphasis on three central themes: (1) Understanding the history of ice shelves and sea ice along northern Ellesmere Island is critical because not only are northern ice shelves valuable sentinels of Arctic climate warming, but they also have implications for shipping given that they reflect sea ice conditions, and their fracturing may spawn ice islands that threaten ship safety. We will reconstruct the Holocene history of northern Ellesmere Island ice shelves from fiord sediment cores. (2) Developing records of long-term climate change and the effects of Hudson Bay sea ice in Tursujuq National Park, Nunavik: The Hudson Bay region was among the parts of the Arctic least affected by climate change during the 20th Century; over the past two decades it has been among the most rapidly warming regions largely due to recent sea ice declines. Such changes have important effects on terrestrial ecosystems important to local residents, including lake ice, permafrost conditions and plant phenology. Studies of long-term climate dynamics in eastern Hudson Bay are needed to understand regional climate change and its consequences for terrestrial ecosystems. (3) In the Antarctic Peninsula we will address the hypothesis that human activities related to research stations have produced and/or mobilized contaminants that have been deposited in lake catchments, caused changes in catchment erosion and nutrient concentrations, and altered lake biota. We study reconstruct these changes using paleolimnological studies of lakes on Fildes Peninsula, one of the most impacted regions in Antarctica. We will examine multiple biological and geochemical indicators to establish conditions prior to the arrival of humans and determine the degree of change due to local anthropogenic activities. The understanding of human effects on fragile Antarctic ecosystems will help also help guide future development in northern regions due to the similarities between Arctic and Antarctic ecosystems.***These objectives will be accomplished through analysis of the sedimentary records of lakes and fiords, using modern paleoecological techniques to infer past environmental conditions. Proxy indicators applied in the research will include diatoms, photosynthetic pigments, organic matter and geochemical markers. My research will provide insights into critical issues affecting aquatic ecosystems in some of the world's most rapidly changing regions and the understanding generated by these studies will thus enable northern communities to predict and adapt to future changes of the local aquatic ecosystems that are crucial natural resources. My research will increase public awareness, inform policymakers and assist sound decision making in water use issues.***********