Limnogeology in Central Yakutia (Eastern Siberia)
Funding
Alfred Wegener Institute for Polar and Marine Research
Russian Partners
• Dr. Luidmilla Petstryakova & Margarita Gerasimova
Limnoecology, Diatoms
Yakutsk State University
Department of Biology and Geography
Yakutsk, Russia
• Prof. Dr. Dmitry A. Subetto
Limnogeology
Herzen State University
Department of Physical Geography
St. Petersburg
• Dr. Tatjana A. Kondratjeva
Laboratory for Hydrobiology
Institute for Ecology of Natural Ecosystems
420087 Kazan, Russia
Background
Central Yakutia is situated in one of earths´s extreme landscapes. The area is mostly covered by Taiga vegetation, has an extreme continental climate with a great range between summer and winter temperatures (-60° - 35°C), and is occupied by widespread frozen ground. In contrast to Europe and North America, extended ice sheets were absent during the last climatic glacial-interglacial cycles, while regional glaciation was evident in the Verkhoyansk Mountains. Abundant thermokarst and oxbow lakes, and alas depressions (see above picture of Lake Syrdach) occupy the low lands of Central Yakutia. Lakes of glacial origin appear in the valleys and morainic arcs of the Verkhoyansk Mountains (e.g. Lake Billyakh). The lacustrine sediment records provide insights into environmental dynamics of the late glacial to Holocene period at high temporal resolution. The lake studies are devoted to the following objectives:
• recognition of modern limnoecology and establishment of training data sets for the inference of statistical transfer functions on the basis of aquatic organisms and pollen records,
• reconstruction of the former lacustrine depositional environment and palaeo ecological conditions,
• reconstruction of Holocene lake-level fluctuations in thermokarst lakes response to short-term climate cycles and sub-bottom permafrost dynamics.
The studies concentrate on short sediment cores taken with a gravity corer (see picture above) from several dozens of lakes throughout Yakutia for the reconstruction of the sub-Recent environmental development. The study of Holocene paleolimnology is concentrated on long sediment cores taken from lakes around Yakutsk, Lake Satagay (Vilyuy area), and Lake Billyakh (Verkhoyansk Mountains) (see map).
Outcomes
• Popp, S. (2007). Late Quaternary Environment of Central Yakutia (NE Siberia): Signals in frozen ground and terrestrial sediments. Reports on Polar Research, 554, 80 pp.
• Popp, S., Gerasimova, L., Pestryakova, L., Subetto, D., Nazarova, L., Andreev, A., Meyer, H., Stein, R., Diekmann, B. (in preparation). Mid- to late Holocene climate change and linkages to centennial solar variability in northeastern Siberia: Evidence from a thermokarst lake status record.
• Lüpfert, Hermann (2006). Holozäne Klima- und Umweltentwicklung in Zentraljakutien (NE-Sibirien). Magister Thesis, Humboldt University Berlin / AWI Posdam.
• Kumke, T., Ksenofontova, M., Pestryakova, L., Nazarova, L., Hubberten, H. -W.(2005). Limnological characteristics of lakes in the lowlands of Central Yakutia, Russia, Aquatic sciences.
• Nazarova, L., Kumke, T., Pestryakova, L., Hubberten, H. -W. (2005). Chironomid fauna of Central Yakutian lakes (Northern Russia) in palaeoenvironmental invesstigation, Chironomus, 18, 25-27.