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Ces méthodes de protection des berges ont permis aux pouvoirs publics de sauvegarder les infrastructures et les zones résidentielles ou industrielles construites en zone côtière. Toutefois, les technologies utilisées pour la préservation des berges, qui consistent pour la plupart en protections linéaires en enrochement et en érection de murs verticaux (béton, palplanche, pierres et caissons de bois), sont mal adaptées et causent des répercussions environnementales résiduelles importantes.
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The risk posed by permafrost degradation varies from community to community depending on geomorphology (rock outcrops, granular or clayey soils containing ice, instability factor when thawing). From the tree line to the shores of Hudson Strait, the climatic gradient is such that the discontinuous permafrost, having temperatures near the freezing point, becomes colder as one moves farther north. Consequently, a fairly uniform regional warming would act first on the southern fringes of the permafrost and then gradually on more northerly areas. Up to now, municipal planning has taken into account the nature of the terrain in each community as much as possible. Moreover, most institutional buildings, such as schools and hospitals, and most houses are built on piles or trestles, which allow air circulation and keep the soil at or near air temperature (Fortier and Allard, 2003a, b).
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