Zonation des conditions d'enneigement en toundra forestière, Baie d'Hudson, Nouveau-Québec

• Published in: Canadian Journal of Botany
• Main Authors: Payette, Serge, Ouzilleau, Jacques, Filion, Louise
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1975
• Subjects: Plant Science; Hudson Bay; Hudson; Baie d'Hudson; Baie-d'Hudson; taiga; toundra; Tundra
• Online Access: http://dx.doi.org/10.1139/b75-120; http://www.nrcresearchpress.com/doi/pdf/10.1139/b75-120

Data on snow depth and snow density of various forest–tundra coniferous stands are presented in this paper. A latitudinal pattern in snow conditions is observed in the forest–tundra environment, as predicted from the facts that are obtained when this phytogeographical region is subdivided, firstly, into a forested subzone in the southern part and a shrub subzone (or krummholz) in the northern part and, secondly, into a maritime ecoclimatic area near Hudson Bay and a continental ecoclimatic area inland. The most snowy coniferous stands are located in the shrub subzone; snow density rises gradually from the taiga to the tundra. The highest values in snow properties are found in the maritime ecoclimatic area. These data suggest the following observations: (1) maximum snow depth measured in the northern part of the forest–tundra is explained by an increase of barren ground cover and by the presence of more open coniferous stands, which favor snow drifting and snow trapping; (2) the gradual increase in snow density is related to more rigorous climatic conditions; wind exposure is rather important since these sites are getting more open; and (3) the differences in snow conditions between the ecoclimatic areas show that the maritime environment is more windy; the presence of scattered and erected white spruce (Picea glauca (Moench) Voss) in various krummholz formations in that area favors more efficient snow traps than those of krummholz formations located in the continental area. The latter is dominated by prostrate and erect black spruce (Picea mariana (Mill.) BSP.) always densely agglomerated. The latitudinal pattern in snow conditions reflects the climatic conditions of the forest–tundra, and this determines the specific ecological distribution of coniferous stands.