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Based on the palynological analysis of the bottom sediment column of the arctic lake with the code name K1 of the Yerkuta river basin from the southwestern part of the Yamal Peninsula, we received a preliminary information on climatic changes, as well as on changes in vegetation character in the area around the water body. Reconstruction of vegetation around the lake has identified the development of a brush-grass-moss tundra. Shrubs are represented by Betula sect. Nana, Alnaster, Salix sp., Ericaceae. Herbaceous ...

In this study, variations in the paleoecological conditions of Western Siberia were analyzed. For the paleoecological studies, a core of bottom sediments, 51 cm long, was taken from an unnamed lake located in the Yamalo-Nenets Autonomous Okrug. A total of 26 samples from the core were examined in detail. As a result, 30 cladoceran taxa were registered. Among them, Bosmina (Eubosmina) longispina was dominant throughout the core. The subdominant species were Alonella nana and Chydorus cf. sphaericus from the family ...

This investigation is aimed to determine the general development phases of the vegetation and climatic situations of the Pur-Taz interfluvial region, Western Siberia (Yamalo-Nenets Autonomous Okrug, Russia) based on the spore-pollen analysis of the bottom sediments of the Lake 17-Ya-01. The palynological analysis was carried out on the basis of 26 samples. In total, 26 palynomorphs have been identified. A spore-pollen diagram, which has been divided on the 4 biostratigraphic sequences (pollen zones PZ I-IV), refle...

For the Arctic region of Russia, an inventory of the biodiversity of aquatic ecosystems for the purpose of environmental monitoring is extremely urgent. Global warming for terrestrial ecosystems manifest as changes in the distribution of individual species and assemblages, in the timing of important life-cycle events, and in abundance and community structure. Zooplankton communities in the Northern lakes are highly diverse and thus perform a variety of ecosystem functions. The most important role of zooplankton is...

Russian Arctic regions are most sensitive to global climate change. Their unique and fragile ecosystems are very dependent on freshwater. Beyond temperature rise, climate change is accompanied by shifts in precipitation and wind conditions, thereby causing floods, droughts, and altered mixing regimes, all having a serious impact on the abiotic and biotic structure. This work is relevant for better understanding of the biota of the Russian Arctic. Cladocerans are very promising for studying climate change risks owi...

Diatoms are widely used for paleoindication, through which the main stages of life of lakes against the background of changing environmental conditions determined by both natural and anthropogenic factors can be reconstructed. The results of the diatom analysis of a 96 cm long continuous sediment core from the artic lake in the Pechora River delta (Nenets Autonomous Okrug, Russia) were presented. The arctic lake under study is characterized by low conductivity and nutrients content. In 33 samples taken from the la...

The Yamal Peninsula is one of the most important strategic oil and gas-bearing regions of Russia. Active development of the Far North territories threatens to have negative consequences for the delicate balance of Northern ecosystems, therefore their monitoring and comprehensive research are particularly relevant. In 2012-2013 during the expeditions on the Yamal, Yavay and Gyda peninsulas bottom sediments of the Unnamed lake (57.5 cm; 1300 cal yr BP), located in the catchment area of the Pyasedayakha river, were s...

The pollen record from a 96 cm long sediment core obtained in Lake Arcto-Pimberto (68°26.114' N, 053°32.311' E, Pechora river delta, Nenets Autonomous Okrug) reflect regional vegetation and climate changes in the north of the Eastern European plain over the last 6000 year. The taxonomic and stratigraphic structure of the column of bottom sediments is reflected in a spore-pollen diagram which was divided on the 4 biostratigraphic sequences - pollen zones (PZ I-IV). The results show that the bottom of the core (PZ I...

The article describes a long-term and seasonal dynamics of zooplankton species diversity and its relationships with hydrologic factors were investigated on Lake Fish located in Samoylov Island on the northeast of the Republic of Sakha (Yakutia), Russia. This lake was chosen as a research object due to its mixed type of origin: thermokarst-polygonal. Zooplankton was sampled at three locations: on the pelagic and littoral zones of the thermokarst part and polygonal part of the lake. In total, 90 taxa (80 species) of...

The aim of the study was the analysis of subfossil Cladocera community of the Kotovo lake (Kharbey lakes' system, Bolshezemelskaya tundra) and the qualitative rating of the changes in it and in the region of study. The relevance of the work is associated with the increasing interest to the study of the climate change on the example of the North intact territories, along with the insufficient knowledge of the biota of the area being studied. The predominance of some species, zoogeography and biotopic attachments of...

The aim of our investigation is to reconstruct the local and regional palaeoenvironmental conditions and to highlight the rapid evolution of the thermokarst lake during the Holocene climate optimum. The investigated lake was located in Central Yakutia, Siberia, Russia. The investigated core was collected in a small pingo within a large Central Yakutian thermokarst Khara Bulgunnyakh basin (alas). According to ephippium analysis the formation of the lake coincided with the Holocene climatic optimum. Using cluster an...

This investigation is aimed to determine general development patterns of the natural and climatic situations and lakes of the boreal zone in the later and postglacial time in the southeastern periphery of the Fennoscandian crystalline shield since the time of the last deglaciation. The analysis of the subfossil Cladoceran community was carried out on the basis of the 23 samples of Lake GahkozeroпїЅ bottom sediments in the Republic of Karelia. In the subfossil Cladoceran community of the lake 42 taxa have been iden...