The effects of snow packing on tree growth forms on an island in a recently created reservoir in northern Québec, Canada

This study aims at determining the dendrochronological indicators of a changing snow accumulation regime on an island of a recently created reservoir in northern Quebec. Reservoir Robert-Bourassa (LG-2) is a vast lake (2,835 km2) covered by ice from mid-December to mid-May. Snow drifts across the frozen lake until it is trapped by obstacles on islands and at reservoir margins. Pre-established trees on the islands are negatively affected by the local augmentation of snow accumulation. Changes in tree growth forms of a severely exposed forested island indicate that damage occurred soon after reservoir filling. At the island edges, the decay of trees increases the wind exposure of border trees, causing massive foliage loss, thus reducing tree growth. Beyond the edge, in the island interior, drifted snow accumulates due to the wind breaking effect of the shoreline trees. Since reservoir filling, incidents of stem breakage, shoot bending and tilting, and branch tearing have increased due to snow packi...