Ecological State of Lake Gusinoe—A Cooling Pond of the Gusinoozersk GRES

The study of the transformation of substances in the basin of the Selenga River—the main tributary of Lake Baikal—under anthropogenic pressure and in the context of global climate change, is especially important for the lake, a globally important source of drinking water. The ecosystem of Lake Gusinoe is one of the key objects in the Selenga River basin that is exposed to significant anthropogenic pressure. This study presents the results of an analysis of water level changes and physicochemical parameters of the water mass of Lake Gusinoe; literature data from 1951 to 2017 and own data from 2017 to 2021. The water level in the lake had depended on natural factors before the Gusinoozersk GRES was launched; however, since the plant has begun using the lake as a cooling pond, its level has actually been regulated by the economic entity. Over the years, there has been a significant increase in mineralization, sulfate, sodium, fluoride and organic matter fractions resistant to oxidation. Seasonal increases in iron and manganese concentrations in water were detected. Increased concentrations of nutrients and organic matter fractions resistant to oxidation were registered at the wastewater discharge sites. Heavy metals in the bottom sediments of Lake Gusinoe accumulate mainly in the silt of the deep zone of the lake. Plants growing in the zones of influence of the Gusinoozersk GRES and Gusinoozersk wastewater discharge accumulate the largest amount of metals.

Influence of abiotic factors on incubation of Baikal omul eggs in the Selenga River (Lake Baikal Basin)

Abiotic factors affecting the choice of spawning sites for the Baikal omul (Coregonus migratorius) in the Selenga River over 27 years were studied. A total of 3,450 samples were collected using the Dulkeit scraper in Decembers of 1987-2014, at 24 trans-sections in the Selenga River channel over a total length of 410 km. At each sampling site we recorded omul egg density, substrate particle size, water depth, water flow velocity, and ice thickness. Omul eggs were found mainly on hard substrates (sand, gravel, pebbles, and pebble-cobbles combinations). Omul has been found to avoid spawning at depths less than 1.5 m and greater than 6.0 m. Water velocity and ice thickness did not strongly influence the choice of site. Omul eggs were found at flow rates of 0.05-0.7 m/s with a maximum at 0.1 m/s.

The content of heavy metals in the water of Lake Gusinoe (Western Transbaikalia) and its tributaries

Investigation of the transformation of substances in the basin of the Selenga River, the main tributary of Lake Baikal, due to anthropogenic impact under conditions of global climate change, is especially important for Lake Baikal which is a World Natural Heritage Site and the main source of fresh drinking water not only in the region, but also in the world. One of the key research objects in the Selenga River basin, which is subject to significant anthropogenic impact, is the ecosystem of Lake Gusinoe. This study presents the results of analysis of the physical and chemical parameters of the water mass of Gusinoe Lake basin. for the period from 2017 to 2020. Thus, the results on hydrochemical indicators for a long-term period of research of the lake show changes in the chemical composition of water and the concentration of main ions. In 2020, the content of almost all metals was higher than in 2017-2020, which may be due to the rise in the level of Lake Gusinoe and groundwater that began in 2019 and continued in 2020, as a result of rain floods that caused flooding of the coastal territories and the entry of pollutants into watercourses and the lake.

Aufeis in the mountainous areas of the northwestern part of the Selenga River basin

The article presents the results of research on aufeis (icings) in the area where their concentration is maximal for the Selenga River basin. Landsat and Sentinel satellite imagery data were used to map the current location of aufeis in the valleys of permanent watercourses of the transboundary Dzhida River basin. It was found out that up to 3.5 thousand small aufeis with the area from 0.005 to 1 km2 are formed in small watersheds of the territory. The total area of aufeis within the considered territory can reach up to 92.1 km2, the aufeis coverage is 0.45%. It is revealed that in the total amount, small aufeis prevail, the area of which lies within 0.01 to 0.1 km2. In addition, ecosystem and economic aspects of the processes of ice formation on the territory of Russia and neighbouring Mongolia are considered.

Navigational Atlas of the Selenga River section within Mongolian People’s Republic, 1925

The article provides information on the manuscript atlas of the Selenga and Orkhon rivers within the Mongolian People’s Republic (MPR), compiled on the basis of data from 1924-1925. It was developed for the Selenga Technical Section of the Ministry of the River Fleet to guide navigation along the rivers of Mongolia. The shooting was carried out on a steam boat “Shilka”. The atlas is of interest for the dynamics of river channel processes in northern Mongolia. The materials provide information on where and how to carry out technical work to improve navigation. In addition to information on navigation, it provides economic and geographical information on the north of Mongolia in the 1920s.

Exomorpholithogenesis of the Selenga River delta at the present stage of the hydroclimatic cycle

The materials of complex interdisciplinary studies of the relief forming in different periods of water availability in the Selenga River delta are presented since the technogenic level rise of Lake Baikal. Four water and sediment runoff anomalies, synchronous with water level fluctuations in the Lake are identified. The current boundaries of the Selenga River mouth area (RMA), floodplain complex, flooding territories in the maximum water ability conditions are identified. The RMA covers the territory from the main channel bifurcation nod to Lake Baikal, includes subaerial and subaqueous parts of the protruding delta, the interaction zone fluvial processes and different-aged terraces deposits and adjacent lagoons Proval and Cherkalov Sor. Semi-empirical models and data on the water runoff and sediment yield are presented.