Wintertime Infiltration and Snowmelt Processes of Black Spruce Peatlands in the Boreal Plain

Understanding surface water groundwater interactions within the Boreal Plains is vital to reclaiming peatlands within Alberta’s Athabasca Oil Sands. After multiple years of field observations, it became apparent that many of the long held assumptions regarding wintertime hydrology and groundwater infiltration were false, especially within the peatlands. During the wintertime, it was discovered that the biological activity of the black spruce trees warmed the subsurface soil beneath the snowpack and thus prevented the ground from freezing. Further multiple wintertime events were observed where canopy snowmelt would directly infiltrate into the peat and not accumulate within the snowpack or sublimate as previously believed.

A conceptual model of how black spruce trees impact the winter hydrology of peatlands will be presented. The importance of incorporating ecology into physically based model which simulate the interactions between surface water and groundwater will be discussed. Brief modeling examples using the USDA Simultaneous Heat and Water (SHAW) model will be used to demonstrate the differences in groundwater recharge between black spruce, lodgepole pine, and burnt forested ecosites, including the additional processes that are required to properly simulate black spruce peatlands. Finally the importance of ecohydrology will be emphasised by demonstracting how simulating groundwater infiltration under varying tree species will provide reclamation specialists an important tool for designing future peatlands.