First results of the paleolimnological research in Tundra polygons (the project POLYGON)

• Main Authors: Sitalo, Viktor, Subetto, Dmitry, Schirrmeister, Lutz, Wetterich, Sebastian, Schneider, Andrea
• Format: Conference Object
• Language: unknown
• Published: 2013
• Subjects: Ice; permafrost; Thermokarst; Tundra
• Online Access: https://epic.awi.de/id/eprint/32518/; https://hdl.handle.net/10013/epic.41122

A joint German-Russian project (Polygons in tundra wetlands: state and dynamics under climate variability in Polar Regions) started in 2010. The first part of field research during the 2011 field campaign in the lower Indigirka River (70°N, 147°E) and the lower (68°N; 161°E). After one month of field work the author has completed sediment samples from typical polygonal ponds on different evolution levels. Eight polygonal ponds and three thermokarst lakes were drilled. Total number of samples is 170. The first task was to capture a certain number of sedimental samples. The analysis of potential indicator organisms in ponds and cryosols in a wider area and the monitoring of species dynamics in ponds at selected locations was completed by further on-site measurements (e.g. temperature, pH, conductivity, acidity, alkalinity, oxygen) and hydrochemical (major ion concentrations), sedimentological (CNS, grain size) and stable isotope lab analyses (δD, δ18O, δ13C) in order to record the life conditions of indicator species during the open water period. These analyses were performed by the involved institutions in Germany. The morphometric description (size, depth, bathymetry, type) of the polygons aims to establish the relationships of these parameters with precipitation and permafrost dynamics during summer. Simple, but stable sensors connected with long-term data loggers (one year records) were installed in selected polygon ponds in the Chokurdakh and the Chersky study areas. These instruments have to be extra purchased by this project. Physico-chemical field data from the study sites was compared and correlated with climate data of the respective climate stations (e.g. air temperature, precipitation, radiation). Summer precipitation was quantified and sampled since it is – next to ice melting - the main source of water in polygon ponds during summer, determining their hydrochemical and stable isotope properties. Compilation of sedimental samples gave data about polygonal ponds with different evolution levels and age. ...