| Date & Time | Tuesday, July 18, 2023, 15:00-15:45 |
| Method | Online | Participant | 14 people |
| Lecturer: Izabella Baisheva（Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research, University of Potsdam, North-Eastern Federal University of Yakutsk, Hokkaido University） Presentation Title: Alaas lakes development and their ecology in Central Yakutia, Eastern Siberia Abstract: With global warming Arctic and subarctic regions face intensified warming, under the Arctic amplification effect. In response permafrost landscapes rich in ground ice are vulnerable to thaw. Freshwater ecosystems and their watersheds are being impacted and significantly altered. In Central Yakutia, ground ice thawing causes a gradual deepening of permafrost active layer (thermokarst depression) and insufficient water supply then leads to the formation of alaas landscapes typical for the region. The formation of alaases has four main stages of development. At a final stage, alaas represents a meadow in a forest in a thermokarst depression with residual lake. Here we present modern state of 51 lakes and also the results of conducted paleolimnological reconstruction from Lake Satagay. Modern state study is based on lake water chemistry and plant genetic metabarcoding analyses from lake surface sediments across Central Yakutia (average elevation 190 m a.s.l.). 51 lakes span different types of formation stages and morphological development, differ in alkalinity, ion composition and lake vegetation composition. Paleolimnological study is based on diatoms and plants genetic metabarcoding, as well as biogeochemical description of sediment core. Our results will enhance the understanding of aquatic vegetation composition in different environments and enrich the existing databases. |
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