Baikal Research Articles

<i>Hofmaenneria baikalensis</i> sp. n. and <i>Paratrilobus longisomus</i> sp. n. (Nematoda) from Lake Baikal

Illustrated descriptions of two new species of free-living nematodes Hofmaenneria baikalensis sp. n. and Paratrilobus longisomus sp. n. found in the Lake Baikal (Russia) are given. Hofmaenneria baikalensis sp. n. is close to H. keoladeoensis Khan et al., 2005, H. niddensis (Skwarra, 1921) Schneider, 1940 and H. sitnikovae Gagarin, Naumova, 2010. It differs from these three species in a presence of crystals in the body cavity and presence of three oval cardial glands. Paratrilobus longisomus sp. n. is close in the body size to P. expugnator (Tsalolichin, 1976) and P. rapis Gagarin, 1991 but it has a relatively shorter and slenderer tail and presence of subterminal seta at the tail end.

On the Influence of Atmospheric Ions on Aerosol Formation: Numerical Modeling

A new mathematical model of the global transport of multicomponent gas impurities and aerosols has been constructed, including the formation of sulfate aerosols in the atmosphere in both hemispheres. Calculations of the nucleation rates and particle number concentrations were performed for the winter period in the troposphere using a unified model that takes into account chemical and kinetic transformation processes (photochemistry, nucleation, condensation/evaporation, and coagulation). Binary nucleation of sulfuric acid and water vapor was coupled with new-particle formation due to atmospheric ions. The numerical results indicate a significant role of ion nucleation in aerosol formation in the Northern and Southern hemispheres in winter. The factors controlling the dynamics of ionic processes in the atmosphere and their influence on the spatiotemporal distribution of aerosol particles involve not only the level of air ionization but also temperature, relative humidity, and the content of sulfur and water vapor in the air. At a height of 4.2 km, the formation of particle nuclei with the participation of ions occurs only over the Lake Baikal and Kamchatka regions as well as the regions of the northeast and northwest of the American continent. Within the regions of localization of this process in the atmosphere, the rate of new particle generation varies by more than an order of magnitude.

REDESCRIPTION OF <i>MORARIA</i> (<i>BAIKALOMORARIA</i>) <i>LONGICAUDA</i> BORUTZKY 1952 (COPEPODA, HARPACTICOIDA, CANTHOCAMPTIDAE) FROM LAKE BAIKAL

An illustrated redescription of the female and male of Moraria (Baikalomoraria) longicauda Borutzky 1952 is presented, a harpacticoid species endemic to the littoral zone of Lake Baikal, Siberia. A neotype is designated, because the type material is lost. The morphology of this species was studied in detail using scanning electron microscopy for the first time. An illustrated description of the mouthparts and antennules is given; that of the swimming legs being expanded. The structure of the genital field is shown and data on morphological variability are presented.

Northeastern coast of Lake Baikal as a habitat of baikal seal <i>Pusa sibirica</i> in the summer period

Filling of the rookeries of baikal seal Pusa sibirica on the northeastern coast of Lake Baikal is surveyed instrumentally for the first time within the boundaries of protected area. The main coastal haulouts of the species are located in this area, so all places suitable by their lithological parameters for the seals rookeries were examined to assess intensity of their use in modern conditions of anthropogenic impact. In total, ≈ 246 km of the coastline were traced, including 170 km surveyed with unmanned aerial vehicle DJI (in 317 minutes) and visual observations on the rest of the coast with binoculars and ground photo- and video-recording. Only 9 % of the surveyed coastline (> 21 km) is suitable for rookeries, located mainly in the northern part of the area. Unfavorable lithological properties (sands, sandy pebbles, small stones, rocks) prevail on the other part of the coast, though many places (usually big boulders) are available for small rookeries there, too. Currently all these places are almost never used by seals, except of short, sporadic haulouts, mainly in June, immediately after complete disappearance of the floating ice. The main reason why the animals leave their traditional rookeries in this area in July-August is an intensive anthropogenic load, in particular at the places where the largest rookeries existed previously, as the bays Frolikha, Ayaya, Khakusy, capes Khaman-Kit, Pongonye, and some others. The leaving of rookeries contradicts to increasing needs of seals for a solid substrate to complete their molt in conditions of climate warming. Possibly, the threat of losing the northeastern coast as a summer habitat for a significant part of the baikal seal population is underestimated.

Effect of Large-Scale Circulation Anomalies on Summer Rainfall over the Yangtze River Basin: Tropical versus Extratropical

Abstract This study investigates the tropical and extratropical circulation anomalies that directly affect the summer rainfall over the Yangtze River basin (YRB). In the lower troposphere, the tropical circulation anomalies that enhance the YRB rainfall manifest as an anticyclonic anomaly over the tropical western North Pacific (WNP) and the extratropical circulation anomalies are characterized by northeasterly anomalies to the north of the YRB. It is found that the heavier the YRB rainfall, the more necessary the cooperation between the tropical WNP anticyclonic anomaly and the midlatitude northeasterly anomalies, and compared to the tropical WNP anticyclonic anomaly, the midlatitude northeasterly anomalies can more efficiently induce the YRB rainfall. Further results indicate that the tropical WNP anticyclonic anomaly exhibits notable quasi-biweekly feature and provides a favorable background for the enhanced YRB rainfall. By contrast, the northeasterly anomalies are dominated by synoptic variability. Furthermore, there are significant precursor signals for the lower-tropospheric northeasterly anomalies. These signals manifest as the eastward propagation of two wave trains in the upper troposphere: a midlatitude one and a high-latitude one, which tend to be independent. The midlatitude one originates around the Mediterranean Sea and propagates eastward along the Asian westerly jet. The high-latitude one propagates over the high-latitude Eurasian continent, from Europe eastward to Lake Baikal and then southeastward to East Asia.

NEW SPECIES OF MICROSCOPIC TURBELLARIANS OF THE FAMILY RHYNCHOKARLINGIIDAE (PLATHELMINTHES, KALYPTORHYNCHIA) FROM SOUTHERN LAKE BAIKAL

Four new species of microturbellarians (Kalyptorhynchia, Rhynchokarlingiidae), each one representing the genera Cohenella Timoshkin 2004, Coulterella Timoshkin 2004, Mariareuterella Timoshkin et Grygier 2005 and Riedelella Timoshkin 2004 were found when studying the benthic communities at the western coast of the southern basin of Lake Baikal, Siberia. Their illustrated descriptions, comparisons and distributional characteristics are given. All species were found in the coastal zone of the lake, at 1.5–3.8 m depths, on sandy or rocky bottoms.

Approaches to the assessment of indirect economic damage from changes in the level of Lake Baikal

Subject. The article considers methodological approaches to the definition of the concept and assessment of indirect economic damage from changes in the level of Lake Baikal. Objectives. The aim is to analyze the adequacy and practical suitability of methodology for assessing the probabilistic damage from harmful effects of water and the effectiveness of preventive water management measures, developed by the All-Russian Research Institute of Economy and Exploration of Mineral Resources (VIEMS). Methods. On the basis of comparative analysis of results obtained under the direct counting method and those under the VIEMS methodology, we underpinned the adequacy of the latter. Results. We used the case of Nizhneangarsk settlement to make estimates of indirect economic damage under the method of direct counting and the VIEMS methodology. The results are comparable, and this enables to speak about the adequacy of the VIEMS methodology . Conclusions. The comparative analysis demonstrates the reliability of results of assessing the indirect economic damage, obtained using the VIEMS methodology. Significant labour intensity, complexity, and often impossibility of estimation by the direct counting method make it possible to substantiate the feasibility of practical application of the VIEMS methodology for assessing indirect economic damage from the negative impact of waters.

Viromes of Coastal Waters of the North Caspian Sea: Initial Assessment of Diversity and Functional Potential

In recent years, the study of marine viromes has become one of the most relevant areas of geoecology. Viruses are the most numerous, genetically diverse and pervasive biological entities on Earth, including in aquatic ecosystems. Information about viral diversity in aquatic ecosystems remains limited and requires more research. This work provides the first-ever look at the current DNA virome of the Northern Caspian Sea. A comparison with other freshwater and marine viromes revealed that the North Caspian Sea virome has the greatest similarity with those of the Baltic Sea and Lake Baikal. The study described in this article expands the knowledge about aquatic viromes and provides key data for a more comprehensive analysis of viruses circulating in the Caspian Sea, the largest inland body of water on Earth.

Integration of Geophysical Methods to Study Deep Structure of the Angara Fault, the Largest in the Baikal Rift

Abstract —The Angara regional fault which is transversal to the Baikal basin totals about 150 km in length and ranks as a major strike-slip fault with the normal component in the seismically active rift zone. Given that its vicinities represent an area with high population density, the emphasis needs to be placed primarily on the study of its structural features. At this, the Angara fault has been poorly studied by geophysical methods. Results of the specialized mapping carried out in the 1990s revealed the block structure of the Angara fault zone, however without a reliable identification of the fault plane, which leaves its position still to be debatable. To establish the Angara fault plane and studying its deep structure, the integration of such geophysical methods as magnetotelluric (MT) sounding, radon emanation and fieldwalking magnetic surveys was required. Their application in the study of the deep structure of the southern parts of the Angara fault allowed revealing anomalies in all of the measured fields, accordingly. The anomaly-forming object, which the authors associate with the deep penetrated Angara fault plane, was expressed in the most distinct way by the magnetotelluric data (as a high-resistivity region (ER = 8500 Ohm∙m) relative to the host rock) and radon emanation survey (radon volumetric activity index RAI ≥ 20). The fact that the magnetic field received only minor distortions from the object may indicate either moderate magnetic characteristics of the latter or a significant occurrence depth. The identified anomaly-forming object localized within the crystalline basement tends to be more sharply expressed in the left bank of the Irkutsk Reservoir, while in the upper part of the cross-section it is overprinted by rocks of the sedimentary cover.

Possible Linkage Between Winter Extreme Low Temperature Over Western‐Central China and Autumn Sea Ice Loss

AbstractBased on reanalysis datasets and sea‐ice sensitivity experiments, this study has pointed out that the autumn sea ice loss in East Siberian‐Chukchi‐Beaufort (EsCB) Seas significantly increases the frequency of winter extreme low temperature over western‐central China. Autumn sea ice loss warms the troposphere and generates anticyclonic anomaly over the Arctic region 1 month later. Under the effects of synoptic eddy‐mean flow interaction and anomalous upward propagated planetary wave 2, the Arctic anticyclonic anomaly strengthens and develops toward Greenland‐Northern Europe, accompanied by a weakened stratospheric polar vortex. In winter, following intra‐seasonal downward propagation of stratospheric anomalies, the Northern European positive geopotential height anomalies enhance and expand downstream within 7 days, favoring Arctic cold air east of Novaya Zemlya southward (the hyperpolar path) accumulating in Siberia around Lake Baikal. In the subsequent 2–3 days, these cold anomalies rapidly intrude western‐central China and induce abrupt sharp cooling, thus more frequent extreme low temperature there. In contrast, the role of autumn Barents‐Kara (BK) sea ice loss exhibits quite different features, mainly favoring northwestern, northeastern and eastern China to experience increased frequency of extreme low temperature in winter.

Annotated catalogue of the type specimens of salmon, cod and cottoid fishes described by Dmitry Taliev

The article provides a brief biography of the ichthyologist Dmitry Nikolayevich Taliev (1908–1952), as well as information and illustrations for 24 taxa described by him from the White Sea (Gadidae – one subspecies), the coast of the Sea of Okhotsk (Salmonidae – one subspecies), Lake Baikal (Cottidae – 2 species and 4 subspecies; Abyssocottidae – 6 species and 8 subspecies), and Lake Baunt (Cottidae – 1 subspecies; Abyssocottidae – 1 species). For 19 taxa, photographs and radiographs of type specimens kept in the collection of the Zoological Institute of the Russian Academy of Sciences (Saint Petersburg, Russia) are presented for the first time. Type specimens of three species and two subspecies from the families Cottidae and Abyssocottidae found in the collection are examined and catalogued. It was revealed that Cottus kessleri bauntovi Taliev, 1946 and Limnocottus kozovi Taliev, 1946 are morphologically similar to Cottus sibiricus, a species widely distributed in Siberia, including Lake Baunt. According to modern fish taxonomy, Taliev’s 12 taxa are valid. Findings of type specimens in the historical collection are extremely important for the scientific community.

Average long-term background contents of chemical elements and organic substances in the flows of the natural component of the “Suspension of rivers” environment flowing into Lake Baikal reservoirs

The physical and chemical state of the waters of Lake Baikal and the flows of the natural component of the environment flowing into and out is one of the most important elements of the chemical interaction of lake water substances with the environment. To study the natural regularities of the distribution of matter in the “substances of Baikal waters – substances of the flows of the natural component of the environment” megasystem, it is necessary to know the background components in the substance of the flows and their amount. The average long-term content of chemical elements and organic matter was estimated in mg/l. The method for calculating average long-term contents (mg/l, %) of chemical elements and organic (Na+, K+, Ca2+, Mg2+, Al, Si, Mn2+, Fetot, SO42-, HCO3-, Cl-, NO3-, PO43-, H+, O2, As, B, Cr, Cu, Cd, Hg, Pb, Sr, Zn, Co, U, V, Br, Rb, Mo, Corg, Norg, Porg, Sorg, CO2, Ti) in natural component flows environment “suspension of the rivers” flowing into the Southern, Selenginsky, Middle, Northern reservoirs of Baikal was developed. The results of analysis of the chemical composition of suspended substances in rivers for 1976-2001 were used. Natural indicators of the contents of chemical elements and organic matter in the suspended substance of rivers are important for comparative assessments, especially under the increased anthropogenic load. The data are necessary for assessing the scale of river chemical input with river suspension into the reservoirs of Baikal and calculating the contribution of the natural environment flows “River suspension” to the chemical balances of the lake reservoirs.

Composition, Concentration and Origin of Polycyclic Aromatic Hydrocarbons in Waters and Bottom Sediments of Lake Baikal and Its Tributaries

The aim of this study was the systematization and generalization of data obtained by authors during the last decade and the comparison of these data with those obtained by other authors. Gas chromatography (GC-MS) was used for the determination of PAHs and the positive matrix factorization (PMF) model and principal component analysis (PCA) were used for source apportionment of PAHs. It was found that the total concentration of 16 priority PAHs in surface waters varied from 5 to 200 ng/L, whereas the concentration of 16 PAHs in bottom sediments varied from 50 to 700 ng/g. The 2–3-ring PAHs were dominant in water, whereas the 4–6-ring PAHs were dominant in sediments. That was due to PAHs fractionation in the soil–water system. The source apportionment results showed that the PAHs in both water and sediments mostly originated from the combustion of biomass and fossil fuels. In contrast to sediments, there was a PAH fraction in water that did not originate from a single source. The pollution of freshwater ecosystems manifested itself in the lack of correlation between values of octanol/water partitioning coefficients and sediment/water partitioning coefficients of PAHs.

Patterns of distribution of polycyclic aromatic hydrocarbons in the system water–hydrobionts system of the lake Baikal

The results of model experiments designed to study the distribution patterns for polycyclic aromatic hydrocarbons (PAHs) of various structures and solubility (naphthalene, anthracene, pyrene, benz(a)pyrene) in the water system of the Lake Baikal (endemic species: freshwater sponge Lubomirskia baicalensis and haric algae Nitella sp.) are presented. The ability of hydrobionts to remove PAHs from aqueous solutions at the highest rate for the first 2-6 hours and with an efficiency of up to 70-95% of the initial content, depending on the mass and type of organism, exposure time, hydrophobicity (solubility) of the compound was revealed. The ability of hydrobionts to accumulate and convert PAHs was, which indicates the active participation of aquatic organisms in the processes of water self-purification from toxic and carcinogenic compounds. The ability to use hydrobionts as bioindicators for assessing the state of the aquatic environment of Lake Baikal was also demonstrated.

THE MAYFLIES (INSECTA, EPHEMEROPTERA) OF THE NORTH OF THE FAR EAST OF RUSSIA

Based on the literature and original data, a review of the fauna of mayflies (Ephemeroptera) of the North of the Russian Far East is given. To date, the faunistic list of mayfl ies in the region includes 72 species from 23 genera and 8 families. In the watercourses of the Magadan Region, 52 species are recorded, Chukotka Autonomous District – 27, the north of the Khabarovsk territory (a part of Okhotsk north of the Tugur River in the south and the Okhota River in the north) – 57, and Kamchatka – 37 species. Within local faunas, species with the Eastern Palearctic type of distribution prevail in all regions of the North of the Far East, reaching a maximum in north of the Khabarovsk Territory (54 %). The species richness of mayfl ies revealed for the North of the Far East is much less than in the watercourses and reservoirs of the south of the Far East and Eastern Siberia (bass of Lake Baikal), but quite comparable with the fauna of adjacent territories and other northern European countries.

ZOOPLANKTON CURRENT STATE AND TROPHIC RELATIONSHIPS IN THE POSOLSKY SOR OF BAIKAL LAKE IN 2022

The present study provides the original results of research of zooplankton in the most typical shallow area of Lake Baikal (Posolsky Sor) in 2022. Changes in species composition, quantitative indicators of development and the structure of zooplankton are analyzed. Since this area of Baikal is considered a feeding ground for juvenile omul, special attention is paid to assessing the productivity of zooplankton as a food supply for fi sh.

Economic and Technical Aspects of the Use of Wood Waste Gasification Power Plants in Decentralized Nature Protection Areas: The Example of the Natural Territory of Lake Baikal

The studies on the assessment of the economic efficiency of local gasifier biomass power plants for power supply to 5 settlements located in the Central Ecological Zone of the Baikal Natural Territory are presented. Various schemes of operation of power plants using biomass as the main fuel (chips or pellets) and options for combined operation with a diesel power plant are considered. The calculation of the normalized cost of electricity for each case is carried out. It is shown that wood chips, as the cheapest wood fuel, it is advisable to reach a distance of no more than 115 km and 180 km compared to pellets and diesel fuel, respectively.

Turn a Shrimp into a Firefly: Monitoring Tissue pH in Small Crustaceans Using an Injectable Hydrogel Sensor with Infrared Excitation and Visible Luminescence

Various implantable optical sensors are an emerging tool in animal physiology and medicine that may provide real-time information about body fluids without tissue extraction. Such sensors are often fluorescence-based and require strong visible external illumination during signal acquisition, which causes anxiety or even stress for small animals and thus may influence the physiological parameters being measured. In order to overcome this obstacle, here, we combined a fluorescent molecular pH probe with upconverting particles within a hydrogel fiber suitable for injection into small crustaceans. The green luminescence of the particles under non-visible infrared illumination excited fluorescence of the molecular probe and allowed for pH measurements after correction of the probe readout for luminescence intensity. The developed optical setup based on a common microscope ensured effective visualization of the sensor and spectral pH measurements through the translucent exoskeleton of the amphipod (Amphipoda, Crustacea) Eulimnogammarus verrucosus, endemic to ancient Lake Baikal. Testing the sensors in these cold-loving crustaceans under environmentally relevant temperature increases showed alkalization of amphipod internal media by 0.2 soon after the start of the experiment, while further increases led to acidification by 0.5. The applied approach for simple sensor preparation can be useful in building other implantable optical sensors for light-sensitive organisms.

Accurate estimation of lake levels by the spatio-temporal modeling of satellite altimetry data

Satellite altimetry is currently one of the most widely used techniques for monitoring lake water levels. Raw altimetry measurements are generally delivered in an ellipsoid height system, while lake heights are finally required in a local level height system to ensure the lake surface being strictly flat under the physical constraints of both gravity and non-gravity factors. Therefore, there is always a need for height system transformation of altimetry data. Many of the previous studies have used orthometric heights in an approximate manner in the altimetric data processing. The geoid errors, together with other error sources, can introduce significant biases into water level estimations. In this paper, we propose a spatio-temporal regression method to calculate orthometric height to level height (O2L) differences, which can be used to yield accurate lake levels from satellite altimetry data. In the experiments conducted in this study, we chose ICESat-2 data to train the O2L bias correction model, and evaluated the algorithm performance on two large lakes in central Asian (Issyk-Kul and Baikal lakes) and one lake in North America (Lake Michigan). The experimental results indicate that the spatio-temporal modeling method performs better than the traditional spatial modeling method in terms of regression accuracy, and the water levels derived from the new method are much closer to in-situ gauging measurements. Influenced by O2L bias, there is often a jitter phenomenon in the time series of lake levels, and the results of different satellites are, accordingly, not mutually consistent. A visual analysis reveals that the spatio-temporal modeling method can greatly reduce the high-frequency bias.

Crystal Chemistry, Thermal and Radiation-Induced Conversions and Indicatory Significance of S-Bearing Groups in Balliranoite

Crystal-chemical features of a sulfide-bearing variety of the cancrinite-group mineral balliranoite from the Tuluyskoe lapis lazuli deposit, Baikal Lake area, Siberia, Russia, have been investigated using a multimethodic approach based on infrared (IR), Raman, and electron spin resonance (ESR), as well as ultraviolet, visible and near infrared (UV–Vis–near IR) absorption spectroscopy methods, luminescence spectroscopy, electron microprobe analysis, selective sorption of CO2 and H2O from annealing products, and single-crystal X-ray structure analysis. Holotype balliranoite and its sulfate analogue, davyne, were studied for comparison. The crystal-chemical formula of the studied sample from Tultuyskoe is Na5.4K0.1Ca2.4(Si6Al6O24)Cl2[(CO3)0.7(SO4)0.18S*0.95Cl0.1(H2O)0.16], where the content of the wide zeolite channel is given in square brackets; S* is total sulfide sulfur occurring as disordered S2●−, cis- and trans-S4, S52−, minor S3●−, and HS− groups. The presence of S52− and HS− groups, the absence of CO2 molecules, and the association with pyrrhotite and Fe-free pargasite indicate that the studied sample crystallized under highly reducing, low-temperature conditions, unlike holotype balliranoite whose formation was related to the Somma-Vesuvius volcanic complex, Italy. Irradiation of balliranoite from Tultuyskoe with X-rays results in the transformations of polysulfide groups other than S3●− into S3●− in accordance with the scheme: S52− → S2●− + S3●−; 3S2●− → 2S3●− + e−; S4 + S2●− + e− → 2S3●−; S4 + S2●− + e− → 2S3●−; S4 + S52− + e− → 3S3●− (e− = electron).