Influences of Source Waters on Alpine River Systems in Tongait KakKasuangita SilakKijapvinga (Torngat Mountains National Park), Nunatsiavut, Labrador

Abstract

Tongait KakKasuangita SilakKijapvinga (Torngat Mountains National Park) encompasses the northern tip of Labrador and is situated at the southernmost limit of the Arctic Cordillera. This region is an integral part of the homeland for Inuit from Nunatsiavut and Nunavik and hosts the only remaining glaciers in continental northeastern North America. Like other high-latitude regions, glacial melt is currently a key source of streamflow in the summer months and provides refugia for cold-water species. Continued climate warming is expected to make streamflow warmer, slower, and less turbid, putting stream function and culturally significant species such as ikKaluk (Arctic char) at risk. Future glacial loss is also expected to transition downstream habitats to resemble those of more barren non-glacial fed watersheds, further affecting ecosystem services, connected habitats, and community resources. This research aims to examine the impacts of cryospheric (ice) and hydrological (water) systems on ecohydrology by exploring glacial and late-lying snow influences on stream composition and riverine habitats. Stream composition and ecological function is examined through a stable isotopic analysis of oxygen and hydrogen and measurements of aqueous dissolved organic and inorganic carbon from stream water samples collected from three watersheds with different dominant water sources: glacial meltwater, snowmelt, and rain and groundwater. As this area has not undergone water sampling in the past this work also established a baseline for future research. With continued climate warming projected to shift the contribution of water sources it is important to know the unique influence each of these have to better predict how upstream and downstream systems will respond to continued change. This will further our understanding of how changes in the cryosphere and hydrosphere impact northern ecosystems and human livelihoods in support of future environmental monitoring, adaptation, and conservation.