Baikal Research Articles

Results of expedition measurements of PM10, PAHs and mercury above the water area of Lake Baikal in August 2023

As a continuation of regular research to obtain information about mechanisms and sources of air pollution above the water area of Lake Baikal, we present the results of the expeditionary studies on the concentrations of РМ10, polycyclic aromatic hydrocarbons and gaseous elemental mercury in the near-water layer of the atmosphere above Lake Baikal in August 2023. On the route of the vessel along the perimeter of the lake, the concentrations of pollutants in the near-water atmosphere increased near the local sources of air pollution located on the coast of the southern basin (Listvyanka, Slyudyanka and Baikalsk) as well as at the source of the Angara River with the northwesterly transport from the industrial cities of the Baikal region. Over the study period, the РМ10 concentrations averaged 6.0 µg/‌m3, PAHs–1.1 ng/m3, and gaseous elemental mercury–0.75 ng/m3, which was lower than the values recorded during wildfires between 2016 and 2020 in some areas of Siberia. The resulting concentrations of the investigated air components did not exceed air quality standards. Pairwise correlations during the study period were high between РМ10 and PAHs (0.71) and low between PAHs and mercury (0.21).

Comparative characterization of anaerobic oil oxidation processes by microbial communities of sediments from natural oil seeps in Lake Baikal (Gorevoy Utes, Bolshaya Zelenovskaya)

The comparative characterization of oil biodegradation processes under anaerobic conditions during the cultivation of microbial communitiesof sediments from two sites of oil seeps is given. The microbial community of sediments from the Bolshaya Zelenovskaya River oil seep, functioning under the conditions of long-term exposure to hydrocarbons, is focused more on the processes of anaerobic oxidation of oil in comparison with the microbial communities of sediments from the oil seep located near Cape Gorevoy Utes. This is evidenced by the high level of hydrocarbon biodegradation in both surface and deep sediments, regardless of the electron acceptors present in the medium. Oil degradation in enrichment cultures was accompanied by the formation of hydrocarbon gases (methane and ethane). The highest concentration of methane formed was found in the experiment with sediments from Cape Gorevoy Utes. Ethane generation, on the contrary, was more typical of the cultivation of communities from sediments of the Bolshaya Zelenovskaya River. Microbial communities functioning under anaerobic conditions in sediments at the sites of oil seeps are no less important in the processes of self-purification of the lake from oil “pollution” than aerobic microbial communities of the water column and surface sediments.

Characterization of Saccharimonadia bacteria in Lakes Baikal and Khubsugul: taxonomic and functional diversity

Ultra-small bacteria are ubiquitous in the environment, but for some time they have remained out of scientific focus. One of the reasons is their small size. Ultramicrobacteria, which are defined as bacteria with a cell size of less than 0.1 µm3, can pass through a filter with a pore size of 0.2 µm. Moreover, there are some difficulties associated with their cultivation. Currently, relatively pure cultures have been obtained, but mostly for dominant phyla. Rare phyla are represented only by single strains. At the same time, ultramicrobacteria are found in a wide range of environments, and their high-ordered, small genomes and unique physiological features attract the increasing attention of researchers. The development of metagenomics allows us to partially overcome cultivation limitations, and in this article, we present metagenomic assemblies derived from water samples of the largest oligotrophic lakes on the Earth, Baikal (Russian Federation) and Khubsugul (Mongolia). In this study, we carried out the taxonomic and functional analysis of reconstructed genomes of Saccharimonadia class bacteria (phylum Patescibacteria), which is intended to expand our knowledge of rare representatives of microbial communities and supplement the already available information regarding the inhabitants of the oldest ecosystems.

Investigation of Tychonema sp. tropism to the sponge body in the experiment of co-cultivation of cyanobacteria with primmorphs

Mass death of endemic sponges accompanied by the growth of cyanobacterial biofilms on their bodies has been registered in recent years in Lake Baikal. These biofilms are formed by the cyanobacterium Tychonema sp., which grows on various types of substrates in the littoral zone and is often found on sponges. The aim of the study was to conduct an experiment on co-cultivation of Tychonema sp. with Baikalospongia sp. primomorphs to test the hypothesis about the tropism of Baikal cyanobacterium to the body of sponges. In the experiment, gradual fouling of the primmorphs with cyanobacterium filaments, destruction of their structure and death of sponge cells were registered. In the control without addition of cyanobacteria, the primmorphs remained alive during the whole time of the experiment.

Agglomerative approach to the analysis of wind regime over Lake Baikal during the existence of the autumnal thermal bar

An approach based on agglomerative hierarchical clustering of wind direction data is proposed to analyze the wind regime over the middle Baikal region. Wind direction data were obtained from an objective National Centers for Environmental Prediction (NCEP) analysis. The constructed maps agree well with the measurement data collected at the meteorological stations in the Irkutsk and Zabaykalsky departments of Hydrometeorological and Environmental Monitoring.

Search for putative complete and near-complete genomes of DNA-containing viruses in metagenomes obtained from the Lake Baikal

The paper presents the analysis of putatively complete and near-complete genomes of bacteriophages extracted from metagenomic data obtained from DNA samples isolated from Lake Baikal water using modern bioinformatic programs. A total of 73 sequences with lengths ranging from 13.8 kb to 163.7 kb belonging to phages of the Caudoviricetes class were identified. Two contigs belonging putatively to cyanophages with lengths of 36.8 kb and 163.7 kb were detected, and in the latter one an ORF with a length of 159 amino acid residues similar to the small heat shock protein (Hsp20) was identified. Analysis of the amino acid sequences identified in the assembled bacteriophage genomes using the PHROG database revealed that 27.5% of them have an unknown function, while the majority of those with similarity to known ones (23.7%) belong to the category “DNA, RNA and nucleotide metabolism”. A number of accessory metabolic genes (AMGs) were also detected in the assembled genomes: nadM, cysC, cobS, galE, cobT, etc. Most of the sequences with similarity to sequences from the IMG/VR database (89.6%) corresponded to sequences obtained from freshwater bodies.

Search for bacteria capable of biodegradation of microcystins in Lake Baikal using molecular-biological technologies

In aquatic ecosystems, biodegradation of microcystins is the main route of elimination and detoxification. In this study, we discuss the ability of bacterioplankton of lakes Baikal, Doroninskoye, Gusinoye to degrade cyclic microcystin molecule. PCR analysis showed the absence of the key enzyme microcystinase mlrA for mlr-pathway. At the same time, metagenomic analysis of a community of the toxic cyanobacterium Tychonema sp. BBK16 revealed the presence of the mrlC gene responsible for cleavage of microcystin molecule linear residues. In addition, all bacteria-symbionts of cyanobacteria contain glutathione transferases - enzymes involved in nonspecific degradation of lipophilic toxic substances, which also include microcystins.

Biological diversity and structure of sub-ice algal-bacterial communities in the Maloye More Strait (Lake Baikal)

An analysis of the taxonomic structure and diversity of sub-ice algal-bacterial communities in the Maloye More Strait of Lake Baikal in two different ecotopes (the bottom surface of the ice and the water column) was carried out. According to high-throughput sequencing of the 18S rRNA fragment and microscopy, the dinoflagellates Gymnodinium baicalense and green algae Binuclearia lauterbornii predominated on the bottom surface of the ice, while the diatoms Ulnaria acus and Fragilaria radians and green algae of the genus Monoraphidium> and Koliela predominated in the water column. In the bacterial communities, the most abundant phyla were Actinobacteria, Proteobacteria and Bacteroidetes.

Identification of microcystin producing cyanobacteria in the plankton of Lake Baikal and Irkutsk Reservoir

Genes of synthesis of hepatotoxic microcystin belonging to the genera Microcystis and Dolichospermum (Anabaena) were previously identified in samples of plankton from Lake Baikal and reservoirs of the Angara HPP cascade. However, accurate identification of toxin producing species is not possible without culture studies. In this study, 17 strains of planktonic cyanobacteria belonging to the most widespread species in water bodies of temperate zone were obtained by isolation and propagation of individual filaments or colonies. Using molecular biological and immunoassay analyses, it was revealed that the species Dolichospermum lemmermannii and Microcystis aeruginosa were microcystin producers. Of the eight D. lemmermannii strains obtained, only two produced microcystins, their morphological feature being the ability to form large colonies.

Production of the violet pigment violacein by psychrophilic strains of bacteria: extraction and identification

Psychrophilic pigment-forming strains, isolated from Lake Baikal and the Pokhabikha River, were studied. Based on culture-based, morphological, and biochemical properties, as well as the results of 16S rRNA gene sequence analysis, the studied bacteria were assigned to the genera Janthinobacterium and Iodobacter. The strains are able to form biofilms and produce violet pigment. When the pigments were extracted with methanol and identified by MALDI/TOF mass spectrometry, the pigments violacein and deoxyviolacein were identified.

Assessment of the water quality of Lake Baikal and its tributaries in areas affected by local pollution based on microbiological and hydrochemical data

The water quality of Lake Baikal and its tributaries, influenced by seven different local pollution sources, was assessed in the areas of wastewater discharge from wastewater treatment plants (WWTPs) of the towns of Slyudyanka, Baikalsk, and Severobaikalsk, as well as domestic wastewater discharge from tourist resorts and Maksimikha settlement, runoff of hot springs from thermal baths in Zmeinaya Bay, Baikal seal rookeries, and the tourist center on Tonky Island of the Ushkanyi Islands archipelago in September 2022. The waters of the lake and the Rivers Pokhabikha, Maksimikha, and Tyya using microbiological and hydrochemical analysis methods are assessed as clean II class quality (GOST 17.1.3.07-82), except for the coastal water zone opposite the mouth of the Pokhabikha River, where the water is defined as moderately polluted. The unequal distribution of the values of the self-purification coefficient indicates a high abundance of microflora of allochthonous origin and a low activity of autochthonous microorganisms involved in self-purification processes in the studied areas of the lake. It was found that wastewater discharged by treatment facilities; water at the mouth and surface water of the Baikal in the estuary of the Pohabikha River, water in thermal baths of hot springs in Zmeinaya Bay do not meet the requirements of SanPiN 1.2.3685-21 for the maximum permissible amount of generalized coliform bacteria, Escherichia coli and Enterococcus. At all control stations in the pelagic zone of Lake Baikal, remote from the studied local polluted sites, water quality indicators did not exceed the safety water standards for surface water bodies in terms of microbiological and hydrochemical parameters.

Дневник полевого этапа Международной школьной геологической экспедиции «Восточные Саяны – оз. Байкал 2024» Россия-Кыргызстан

The four-day field work of the International School Geological Expedition to Lake Baikal near the Bolshoi Goloustnoye settlement is summarized and briefly covered. Goloustnoye, within the framework of which educational geological studies of magmatic and metamorphic formations of Early Proterozoic (seaside complex of granodiorites and Olkhon series), Riphean (Baikal series: Golousten, Uluntu and Kachergat formations) age, as well as proluvial, fluvial and slope modern sediments were carried out. In the course of the routes, methodological issues of route maintenance were additionally highlighted. Teams of schoolchildren from Tatarstan, Buryatia, Irkutsk region and Kyrgyzstan took part in the expedition. The host organizing party was Irkutsk State University, Department of Geology. At the request of the Russian Geological Society Ltd.

Stray bird species are reference points of the initial stages of changing areas in conditions of directional climate change (on The example Eastern Siberia)

We have shown that Eastern Siberia has now become the scene of climate change, which is determined by its location – the center of Inner Asia. It was found that as a result of increased solar activity on the western edge of Eurasia, the latitudinal transfer of air masses was replaced by a meridional (North Atlantic sector) one. Later, such a shift was observed in the eastern (Pacific) sector of Asia. As a result, a hotbed of elevated surface air temperature was formed in Eastern Siberia and adjacent areas of Mongolia and China, and distant bird evictions to the north, east and west were observed. It is shown that such flights are the first stage of the transformation of bird areas. In the first half of the 20th century, weak western and eastern bird streams have already reached of the hollow Lake Baikal. By the middle of the 20th century, 60 new bird species had been recorded here, but their numbers were insignificant. Subsequently, there were clear trends among them towards further expansion of their areas. It is proved that long-range flights of new species are the first benchmarks indicating the upcoming changes in bird areas. Their consequences should be taken into account in economic activities.

Морфометрические параметры Oxytropis popoviana Peschkova из природных популяций северо-западного побережья озера Байкал (Иркутская область)

Morphometric parameters (plant height, number, length and width of vegetative and generative organs) of living specimens of the rare endemic plant Oxytropis popoviana Peschkova from reference natural populations of the northwestern coast of Lake Baikal were studied for the first time. The variability of various signs has been studied. The obtained morphometric parameters of O. popoviana were compared with those given in the protologue of this species and with the parameters of the closely related species Oxytropis grandiflora (Pall.) DC. The study of the variability of signs for use in diagnostics showed that the most stable parameters of the flower are: the length and width of the flag, the length and width of the boat, the length and width of the cup, the length of the wings. The length and width of the beans also change little. The lengths of the tip of the boat and the bean, as well as the signs of the leaves, are the most variable. A comparison of the morphometric parameters of O. popoviana obtained by us with the values indicated in the O. popoviana protologue, as well as with the data for O. grandiflora, showed the uniqueness of O. popoviana plants in the natural populations of Rytiy and Pokoyniki capes. According to the signs of the vegetative sphere, they approach O. grandiflora, and according to most quantitative and qualitative generative signs they correspond to the parameters of O. popoviana indicated in the protologue, or approach them.

Florogenetic signals with increasing tourist activity in the Pribaikalsky National Park

The article is devoted to the topical issue of studying and conservation of biodiversity of the unique natural territory of the western shore of Lake Baikal, which is located in the northern part of the Small Sea. Small Sea. The increase in tourist flow will change the habitats habitats of red-listed and endemic species of the Pribaikalsky National Park (PNP). National Park (PNP). Climatic and edaphic characteristics of the study area are given. Ecological characteristics and floristic richness ecological characteristics and floristic richness of the habitats of plant species in the PNP. Habitats of plant species in the PNP. Describes plant communities successional type plant communities in anthropogenically disturbed areas are described. Causes of anthropogenic impact and recommendations for restoration of natural communities are given. Restoration of natural communities. An assessment is made observed changes and the effect of human activity. Materials of the research are applicable for creation of informational basis for decision-making on prevention of negative consequences of construction of tourist facilities and ecological safety of Lake Baikal.

Studying the number of ammonium-oxidizing bacteria in bottom sediments of Lake Baikal

Using the limiting dilution assay, the number of ammonium-oxidizing bacteria in the bottom sediments of the area of the Baikal Pulp and Paper Mill (BPPM, Southern Baikal) was determined. The maximum number of bacteria under study was determined at the station where treated wastewater from the city of Baikalsk is discharged into the lake.

Vertical distribution of annual water temperature maxima in the southern coastal zone of Lake Baikal

It is frequently observed that an extreme event, such as a temperature maximum, has a greater impact on a lake ecosystem than changes in average conditions. For the first time, we examine the vertical variability of annual water temperature maxima (AWTM) and dates of their occurrence based on in-situ measurements of water temperature with discreteness of 15 minutes for a stable stratification period over eleven years (since 2005 to 2016 except 2009) in the southern coastal zone of Lake Baikal with a bottom depth of 545 m. The estimated statistical characteristics clearly distinguish various features of the vertical distribution of AWTM. There are significant time shifts (about 86 days) between the uppermost horizon (about 15 m) and the lowest 300 m horizon. The average maximum annual temperatures (15 °C) decrease from the upper horizon to a temperature of 4 °C at 300 m depth. To quantify changes in the annual maximum water temperature, the empirical functions were constructed to estimate relationships between AWTM, dates of their occurrence and depth. These dependencies are not linear and verified by independent data. They have fairly high coefficients of determination.

Проблемы и перспективы развития системы охраны всемирного наследия

The trends in the development of the system of protection of unique sites of global significance, created in accordance with the Convention Concerning the Protection of the World Cultural and Natural Heritage of 1972, are analyzed. The significant contribution of the considered legal and institutional mechanisms in the conservation of such sites and the need to strengthen them in the crisis of international relations are noted. The existing problems in the World Heritage protection system are analyzed on the example of the Declaration of principles to promote international solidarity and cooperation to preserve World Heritage, adopted in 2021 at the twenty-third session of the General Assembly of States Parties to the Convention. The persistent imbalance between cultural and natural heritage sites, which is also reflected in the text of the Declaration, is highlighted. A tendency to shift the focus on the selection and inscription processes is identified. There is a divergence between the provisions of the Convention and the practice of its application with regard to the role of the List. One of the serious problems threatening the sustainability of the World Heritage protection system is the systemic divergence between the positions of the World Heritage Committee and its Advisory Bodies. It is stated that there are shortcomings in the work of the Advisory Bodies of the Committee and the need to strengthen the quality of their scientific expertise. The necessity to create a comprehensive national normative-legal framework for the protection of World Natural Heritage in Russia is substantiated. On the example of Lake Baikal the necessity of preliminary scientific assessment of the consequences of changing the protection regime of World Heritage sites is shown. Based on the results of the study, proposals are formulated to improve the list of principles enshrined in the Declaration.

Assessment of Pollution of Sediments of Accumulative Shores of the Yarki Island (the Northern Part of Lake Baikal)

Assessment of Pollution of Sediments of Accumulative Shores of the Yarki Island (the Northern Part of Lake Baikal)

Структурно-гидрографический подход к определению областей формирования стока рек бассейна оз. Байкал в период максимальной и экстремальной водности

The research is carried out determining the role of each link of channel network in the flow formation process and the water regime features for the river systems in the Lake Baikal basin. The period of regular water flow observations is at least 30 years. The structural and hydrographic analysis of river systems made on the basis of comparison of the results of dynamic and static modeling. The dynamic model corresponds to extreme water content, the static model – on the long-time average annual flow. Provinces and intermountain zones were defining based on physical and geographical zoning. The river systems have specific characteristics of flow formation in these zones. The number of permanent, temporary and episodic river mouths flowing into the Baikal are estimated. The power (magnitude) of each elementary link of the river system is estimated. The regions of formation, transit, and accumulation of flow are defined based on the regularities of the structure of the water-erosion network. The map of the spatial and topological distribution of the river systems by flow regions is created based on the results of the research. This research is relevant for obtaining additional information in order to analyze the flow and calculate the maximum water-bearing capacity of river systems.