Supervised by:

Christophe Kinnard (Regular member)

Co-supervised by:

Vincent Maire (Regular member)

Research project description

The influence of snow cover on plant productivity in the High Arctic tundra

IntroductionAs a result of climate change, it is generally observed that snow depth and snow cover are rapidly decreasing in the Arctic, leading to concerns about the response of plants since they do not quickly adapt to abrupt environmental changes. It is uncertain how changes in snow cover will affect plant primary productivity. Currently, satellite measurements indicate widespread greening at high latitudes associated with increased primary productivity. Since snow affects plant development and distribution, it is speculated that changes in snow cover conditions may explain some of the greening detected at high latitudes. The role that snow plays in vegetation changes, however, remains poorly understood. ObjectivesThe purpose of this project is to study the influence of snow cover on plant productivity in a High Arctic tundra context. The project generally seeks to determine how heterogeneous snow cover conditions impact the primary productivity patterns in the Qarlikturvik Valley of Bylot Island. This general objective can be broken down into a few specific objectives: To map changes in snow cover and primary productivity at high spatial resolution at the study site. To analyze spatial and temporal changes in snow cover conditions and primary productivity. To analyze relationships between snowpack conditions and primary productivity, as well as their interactions with topographic moisture. Study sitesThe study site is in the Canadian Arctic tundra, in the Qarlikturvik Valley of Bylot Island, Nunavut (73°08'N, 80°00'W). While the island is generally dominated by glacier-covered mountains, the study site consists of tundra plains and plateaus. Due to differences in soil elevation and moisture, plant communities can be categorized as wet, mesic, or xeric; however, mesic communities dominate the landscape. Finally, there are quite a few differences in small-scale topography (microtopography): flat surfaces, hummocks, and polygons, among others.Material and methodsThe field season on Bylot Island is scheduled to begin in May and end around mid-July. A drone carrying a Duet M (SenseFly) model high resolution multispectral camera will be used to capture images of the study site. Based on the images taken by the drone, values in the red and near-infrared spectral bands of the Duet M camera will be used to calculate the NDVI (Normalized Difference Vegetation Index) in order to assess the primary productivity of a target area. Digital elevation models (DEMs) will be built via photogrammetry to create snow depth maps. For each pixel, the snow disappearance date (SDD), snow depth (HS), topographic moisture index (TWI) and average snow water equivalence (SWE) will be calculated. Finally, the influence of snow on primary productivity will be interpreted with linear mixed models. Expected resultsExpected results from this project include high spatial resolution snow depth and NDVI maps that portray the evolution of snow cover and primary productivity at the study site. Results should also include snow disappearance date (SDD), snow depth (HS), topographic wetness index (TWI), and mean snow water equivalent (SWE) for each pixel of the study site. Finally, the results of the linear mixed models will help identify and understand the variables that exert influences on NDVI, with a focus on snow cover. These results will help improve the understanding of abiotic factors (notably snow) that influence changes in primary productivity in the Arctic tundra.

Research Site Coordinates