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Identifying landscape changes and associated impacts on lakes and rivers in Old Crow Flats, Yukon, Canada
Kevin
W
Turner, Brock University, kturner2@brocku.ca
(Presenter)
Old Crow Flats (OCF), Yukon, Canada is a lake-rich permafrost landscape that is regarded for its rich ecology and cultural heritage. Local observations of landscape changes include drastically fluctuating lake water levels, unpredictable weather, increasing shrub growth, fire and shoreline slumping. The influence of these changes on lake and river hydroecological conditions and carbon mobility remains uncertain. Our research aims to refine our knowledge of the influence of changing catchment characteristics on lake and downstream conditions so that we can improve predictions of how the hydrology and biogeochemistry (e.g., carbon mobility) will respond in the future. We are integrating findings from a decade of lake and river hydrological monitoring with additional field measurements of lake and landscape conditions, and several spaceborne and airborne remote-sensing products. Recent landscape change mapping initiatives include 1) developing a shrub proliferation map for the entire OCF 14,500-km2 watershed, 2) surveying active layer and vegetation properties at six plots of varying land cover types, 3) utilizing UAV images and photogrammetry to quantify sediment and nutrient export from retrogressive thaw slumps to the Old Crow River, and 4) identifying post-drainage lake hydrological and limnological responses. The hydrology and biogeochemistry of 22 creeks and 14 lakes are being monitored using water isotope tracers (δ13C DIC and DOC, δ18O, and δ2H) and a suite of water chemical parameters including DIC and DOC concentrations. Mapping of coupled results are elucidating the relative importance of different thermokarst geomorphic processes on exported water quality and carbon concentrations, including the influence of lake drainage and retrogressive thaw slumping along the Old Crow River network. Field measurements will be used to evaluate the landscape and hydrology modeling utility of several remote sensing products from the 2017 NASA-ABoVE Airborne Campaign. Comprehensive knowledge generated here will be valuable for informing northern stakeholders and land management strategies as climate continues to change. Associated Project(s): Poster Location ID: 67 Session Assigned: Permafrost and Hydrology
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