Geography and Environmental Studies, WLU
The Effects of Climate Change on the Hydrology, Limnology, and Biogeochemistry of Thermokarst Lakes in Wapusk National Park, Manitoba
Wapusk National Park (WNP), located within the Hudson Bay Lowlands (HBL), contains over 10,000 shallow, thermokarst lakes and ponds spanning the boundary between discontinuous and continuous permafrost. Over the past ~50 years, this area has experienced some of the greatest warming in the circumpolar North and is considered one of the most sensitive regions in northern Canada to permafrost thaw. Gaining knowledge about linkages among hydrological processes, limnological conditions, and greenhouse gas exchange in thermokarst lakes is a high priority since climate-driven alterations to lake-water balances may influence limnological properties and hence greenhouse gas evasion rates. This research will involve collecting surface water samples from 20 lakes spanning three different ecotypes (coastal tundra, peatland, boreal forest) within WNP at three different times (spring-summer-fall) over a three-year period (2012-2014) to assess seasonal and inter-annual variability. Samples will be analyzed for water isotope composition (i.e., oxygen and hydrogen isotopes) and water chemistry (i.e., ions, nutrients, CO2 and CH4 concentrations). In addition, lake sediment cores will be obtained and physical, geochemical, and biological techniques will be used to reconstruct hydrological and limnological variability on decadal to centennial timescales. Overall, these results will identify the implications of rapid environmental change on aquatic ecosystems of the HBL in northern Canada caused by thawing permafrost.