Niveo‐aeolian sand deposition in subarctic dunes, eastern coast of Hudson Bay, Québec, Canada

Abstract

AbstractAeolian sand transport during winter and the snow‐free season was assessed quantitatively by direct year‐round field measurements along transects on the lee side of parabolic dunes in subarctic Québec. In 1987–1988, niveo‐aeolian deposition was more important than aeolian sedimentation in three of the four study sites, and contributed > 75% of the total annual accumulation in exposed sites and < 25% in protected forest sites. The maximum depth of interstratified snow and sand deposits (3.5 m) was recorded in March. Semi‐permanent snow lenses may persist longer than 2 years in the aeolian sediments. After dissipation of snow, 22 cm of sand (as a maximum) accumulated on the slipface of the most active dunes, whereas only minor sand accumulation occurred in distant areas from active sand erosion. Wind‐driven sand was dispersed over 7.4 km2 in the Whapmagoostui‐Kuujjuarapik area. The acumulation of snow and sand during the snow season, together with spring thaw and collapse of the niveo‐aeolian deposit, caused different types of injuries to trees, especially in 1985 and 1987 when a maximum of torn branches was recorded over the last 10 year period.