Surface water chemistry in a continuous permafrost region, Central Yakutia, Eastern Siberia

One of distinct features of the ecosystems of central Yakutia, eastern Siberia, is the abundance of thermokarst depressions called "alases," which form by thawing of the upper part of the continuous permafrost. Alases range from several meters to more than 20 m in depth, and in area they range from less than 1 ha to more than 500 ha. Central Yakutia has about 16 000 alases, covering a total area of about 44 million ha (Fedorov and Konstantinov 2003). While many alases are covered by grassland, with or without small ponds, some alases contain sizeable lakes. Another feature of this region is the accumulation of soluble salts in soils and their high alkalinity (Desyatkin 1993, Lopez et al. this volume). The very low annual precipitation of 230 mm and continuous permafrost in central Yakutia inhibit the leaching of soluble weathering products, causing the soils to be highly saline and alkaline. Alases in particular accumulate substantial amounts of salts that had been stored in the permafrost (Desyatkin 1993). This study's aim was to characterize the surface water chemistry in central Yakutia.