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The climate of the region is continental with long, cold winters and short, dry summers. The mean annual air temperature is -5.5°C and four months of the year have a mean air temperature above 0°C. The mean annual precipitation is 416.3 mm (Environment Canada, 2002). Snow precipitation begins in September and the snowmelt period usually begins in April. The vegetation is typical of muskeg taiga with stunted spruce, shrubs, tussocks and mosses. The typical stratigraphy of the ground is a layer of peat (about 30 cm thick) overlying a layer of silt (about 12 m thick, probably a yedema) and finally a layer of till (depth unknown).
A road built in the 1990s is crossing the study site at about 100 meters from the old alignment in a NW/SE orientation. The road is aligned sub-perpendicularly to the local slope. Since its construction, the centerline of the road has subsided due to the degradation of the underlying ice-rich permafrost and the embankment material (coarse gravel) was intersected with the natural drainage network. Excavations done in April 2008 to remove berms on the side of the road revealed the presence of saturated taliks (unfrozen zone within the permafrost) in the embankment material and in the fine-grained natural ground under the road embankment.
One subside was chosen on the upstream side of the road and the second one on the downstream side, far enough to not be affected by the road.
Subsite: ADAPT1 / Surficial geology: Slightly decomposed peat, silty peat and silt / Vegetation: Small black spruces (0-1 m high), moss, lichens, shrubs (labrador tea, bear berries, birches).
Subsite: ADAPT2 / Surficial geology: Slightly decomposed peat, silty peat and silt / Vegetation: Open forest of black spruces (0-10 m high), moss, lichens, shrubs (labrador tea, bear berries, willows).
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