The results of magnetotelluric studies on the profile of the Kuray depression – lake Teletskoye

The results of magnetotelluric studies (MTS) conducted in the western part of the Mountainous Altai region on the profile of the Kurai depression – lake Teletskoye are presented. The profile intersects two large tectonic units – the Mountainous Altai and Teletskaya, bounded by regional tectonic suturs of the Teletsko-Bashkausskiy, Northern Sayans, Shapshalskiy and other faults. The obtained data indicate a fairly fractional recent block divisibility of the Earth’s crust of the Mountainous Altai territory. It is shown that according to the characteristics of the electrical resistivity distribution within the studied profile, large blocks are distinguished that differ sharply in the features of the composition and structure of the Earth’s crust, as well as the manifestation intensity of deep processes. The sections constructed from magnetotelluric data allow us to trace the behavior of the main neotectonic disturbances, which are marked by subvertical zones with abnormally low resistivity values (1-5 Ohm·m).

NUMERICAL SIMULATION AND FIELD STUDIES OF THERMAL BAR IN LAKE TELETSKOE

A computer three-dimensional (3D) hydrothermodynamic model was designed for refined description of intra-annual temperature stratification in deep freezing Lake Teletskoye. The work is aimed at testing this model through simulation of a complex hydrophysical phenomenon, i.e. spring thermobar for real conditions of Lake Teletskoye. In June 2018, while performing field observations of temperature stratification in Lake Teletskoye, a thermobar (stretching from the mouth of the Chulyshman River at the lake’s southern tail up to its deep-water part) was detected and studied. Using the constructed 3D model of thermal regime and actual input data for 2018, the estimate of spring-summer thermobar in the water body as well as the comparative analysis of numerical simulation results and field observation data were made.

True bugs (Hemiptera: Heteroptera) from the taiga zone of the mountainous Altai of Russia: the first records and new data on rare species

Twelve species are recorded for the first time from the Altai Republic, Russia, based on the materials collected by authors in the vicinity of the northern part of Lake Teletskoye in the southern taiga of Western Siberia. Nabis (Dolichonabis) americolimbatus (Carayon, 1961) is recorded for the first time for the Western Siberia. Seven species, Pachycoleus pusillimus (J. Sahlberg, 1870) (and family Dipsocoridae Dohrn, 1859), Saldula orthochila (Fieber, 1859), Xylocoris cursitans (Fallén, 1807), Acalypta carinata (Panzer, 1806), Empicoris vagabundus (Linnaeus, 1758), Drymus brunneus (R.F. Sahlberg, 1848), Scolopostethus thomsoni Reuter, 1875 are recorded for the first time from the Russian Altai. Four species are recorded for the first time from the Altai Republic – Phytocoris longipennis Flor, 1861, Nysius helveticus (Herrich-Shaeffer, 1850), Kleidocerys resedae resedae (Panzer, 1797), Cymus glandicolor Hahn, 1832. For each species the general distribution, the detailed distribution in the adjacent territories of Siberia, and the data on the biotopic confinement are provided. In addition, the data on the abundance and ecology of some other rare species are provided.

Feeding habits shape infection levels by plerocercoids of the tapeworm Triaenophorus crassus in muscle of a sympatric pair of whitefish in an oligotrophic lake

Lake Teletskoye (West Siberia, Russia) is inhabited by a sympatric pair of whitefish, with each member of the pair being characterized by different feeding habits. Coregonus lavaretus pidschian (Gmelin, 1789) is a large ‘benthivorous’ form, while C. l. pravdinellus (Dulkeit, 1949) is a small ‘planktivorous’ form. Fish were collected from the end of August to the middle of September in 2017 and 2019–2020 in the north part of Lake Teletskoye. For the ‘benthivorous’ form the prevalence, intensity and abundance of T. crassus ranged from 22.4% to 51.9%, 1.9–2.8 and 0.4–1.3, respectively, whereas the same indices for the ‘planktivorous’ form ranged from 94.7% to 97.5%, 4.2–4.8 and 4.0–4.7, respectively. The level of prevalence of infection and abundance of T. crassus in muscle was relatively stable among studied years for both forms. The level of prevalence was higher in the years 2019 and 2020 than in 2017 for the ‘benthivorous’ form, whereas for the ‘planktivorous’ form this index did not change during the studied years. For the first time, a partial sequencing of the cox1 gene (593 bp) for T. crassus was sequenced. All 15 plerocercoids of T. crassus were represented by four haplotypes.

IMPACT OF THE BIOGEOCHEMICAL SITUATION AT CATCHMENTS ON THE MICROELEMENT COMPOSITION OF LAKE TELETSKOYE TRIBUTARIES’ WATERS

Introduction. The formation of the microelement composition of surface waters in reservoirs and watercourses is determined by the biogeochemical processes in the catchment area. However, the schemes and mechanisms of interaction between watercourses and the soils drained by them have been studied insufficiently. Lake Teletskoye is the largest water reservoir of Altai, one of the deepest lakes in Russia, and its catchment area is 90 times larger than the area of the lake itself. Methods. We collected water samples in Lake Teletskoye tributaries during the summer low water period, in the estuaries of rivers. The ionic composition of waters and water extracts from soils (1:5) was determined using standard methods with a titrimetric finish. The content of trace elements (Cd, Cu, Fe, Mn, Ni, Zn, Pb, Cr, Co, V) in filtered water samples, suspended water matter and water extracts from soils was determined by atomic absorption spectrometry using electrothermal atomization on a SOLAAR M6 device. Results. The article presents the results of macro - and microelement composition studies of Lake Teletskoye tributaries’ waters. It is shown that the waters of the studied tributaries are characterized by a low total content of the main salt composition components. A dependence of the content and distribution of trace elements in the “water – suspended matter” system on the catchment landscape and geochemical features was found. Conclusion. The content of the water-soluble forms of Cd, Cu, Fe, Mn, Zn, Pb, Co, V in Lake Teletskoye tributaries’ waters conforms to environmental and sanitary requirements. It was found that Fe, Zn and Cr migrate mainly as the soluble compounds, while Pb, Mn, Cu migrate mainly in suspension. It was revealed that the different soil cover structure of the eastern and western lake shores determines different conditions for the hydrochemical flow formation of their rivers and, as a result, forms the differences in the physical and chemical composition of the eastern and western tributaries’ waters.