Anionic toxicants’ effect on Viviparus viviparus L. hepatopancreas tissues
T.S. Droganova, A.A. Lazareva, L.V. Polikarpova, D.A. Areshidze, N.V. Vasiliev
Section: Ecotoxicology
The effect of elevated concentrations of anionic ecotoxicants (using nitrate and arsenate anions as an example) on the morphofunctional state of tissue and the activity of acid phosphatases (AсP) in the Viviparus viviparus L. hepatopancreas was studied. It was found that the phases of AcP activity after exposure to the nitrate and arsenate ions do not coincide with those in the control. Changes in the specific activity of acid phosphatase in the tissues of the hepatopancreas of mollusks were not accompanied by a change in the number of multiple forms and indicated a metabolic disorder in the animals studied. The latter was confirmed by an assessment of the tissues morphofunctional state. When exposed to nitrate anions, there are relatively small phases of increase and decrease in the specific activity of AcP (by 1.5 times compared to the control values). The enzyme activity remains above control values by 96 hours of exposure. Morphological changes are heterogeneous – some epithelial cells are necrotic, in some sites the epithelial cells are hypertrophied, vacuolated, but not destroyed. The exposure to arsenate anions leads to more pronounced tissue pathology (the nuclei of epithelial cells are at different stages of destruction, the tubules are deformed or destroyed, the stroma grows) and a significant change in enzyme specific activity, which does not stabilize even 30 days after the toxicant removal from the water. The AcP activity in V. viviparus can be a marker of toxic effects on living organisms in ecological and biochemical monitoring of freshwater pollution.
Keywords: ecological and biochemical monitoring, aquatic organisms, Viviparus viviparus, acid phosphatase, enzyme activity, multiple forms of enzymes, nitrate and arsenate anions, morphofunctional state
Article published in number 2 for 2026 DOI: 10.25750/1995-4301-2026-2-174-182
Views: 3
Amphiphilic properties of soil organic matter in the first years after stand cutting
V.V. Startsev, A.A. Dymov
Section: Chemistry of natural environments and objects
The cutting industry is one of the factors that makes a significant contribution to the disruption of forest ecosystems. The aim of the work is to study the hydrophilic and hydrophobic components of organic matter in soils after cutting. The paper presents data on amphiphilicity of organic matter of podzolic soils (Retisols) after clear-cutting with the use of multi-operational harvester/forwarder complexes. The study was conducted on different technological elements of clearcutting: apiary plot and drags (3P – three passes of harvesting equipment, 10P – ten passes, 10P – followed by leveling). Hydrophobic interaction chromatography was used to study the amphiphilic properties of soil organic matter (SOM). It was found that for all sites there is a high content of hydrophilic fractions characterized by high migration and reactivity, both in litter and mineral horizons. Their share increases in the process of reforestation. There is an accumulation of hydrophobic lignin-containing fractions formed as a result of decomposition of plant residues in the soils of windrows. It was found that hydrophobic fractions consisting of lignin–containing compounds have a high degree of correlation with total soil carbon (r = 0.69–0.77, p < 0.05), total nitrogen (r = 0.66–0.79, p < 0.05) and water-soluble carbon fraction (r = 0.45–0.74, p < 0.05). It is shown that organic matter reacts sensitively to anthropogenic load at the level of amphiphilic fractions content, as it significantly differs from the initial indicators after clear-cutting. The accumulation of hydrophobic lignin-containing fractions, formed as a result of decomposition of plant residues, occurs in the soils of windrows as a result of mechanical mixing of the upper mineral horizons with the litter as a result of the passage of heavy wheeled machinery.
Article published in number 2 for 2026 DOI: 10.25750/1995-4301-2026-2-129-136
Views: 3
Heterotrophic bacterioplankton in the Kama reservoirs in summer 2022
M.V. Umanskaya, E.S. Krasnova
Section: Monitoring of natural and anthropogenically disturbed areas
The paper describes the size-morphological structure and spatial distribution of heterotrophic bacterioplankton in the Nizhnekamskoe, Votkinskoe and Kamskoe Reservoirs in August – September 2022. The total abundance of heterotrophic bacterioplankton in the studied reservoirs varied within the range of (1.91–8.74) · 106 cells/mL (on average (3.8±1.2) · 106 cells/mL), biomass – 44.1–190.8 µg C/L (91.0 ± 29.3 µg C/L), which corresponds to the mesotrophiceutrophic level of productivity. The composition of bacterioplankton was dominated by small single free-floating heterotrophic bacteria, mainly cocci and cocobacilli. Unicellular filamentous cells constantly present in the samples during the observation period, and were an integral component of heterotrophic bacterioplankton, despite their small abundance at most stations. In the mouth areas of the tributaries, the number of bacteria was 1.5–2.0 times higher than in the adjacent areas of the reservoirs. This may be due to the fact that mouth areas are a kind of barrier between the tributary and the reservoir, where transformation and accumulation of river flow occur, i.e. they represent ecotones characterized, among other things, by an increase in the abundance of organisms. Aggregated bacterioplankton was mainly associated with detritus particles and made a significant contribution to the total abundance of bacteria, mainly in the mouth areas of tributaries. Picodetritic particles were constantly present in all samples and exceeded the mass of bacterioplankton by 2.8 times, and their greatest number was found in the mouths of tributaries. The water in all reservoirs of the cascade corresponded to the IV (polluted) quality class in terms of the number of bacterioplankton.
Keywords: heterotrophic bacteria, detritus, spatial distribution, the Kama reservoirs’ cascade
Article published in number 2 for 2026 DOI: 10.25750/1995-4301-2026-2-092-099
Views: 6
Using microalgae biomass to capture CO2 from flue gases and produce biodiesel: a review
A significant number of industrial enterprises, particularly in the energy sector, emit greenhouse gases, resulting in the formation of large quantities of carbon dioxide (CO2). Capturing CO2 contained in flue gases, particularly from thermal and combined heat and power plants, is possible for microalgae cultivation, as their biofixation efficiency is significantly higher than that of plants. Flue gases can serve as a source of CO2 and nutrients for microalgae cultivation. Thus, modern technologies make it possible to convert polluting flue emissions into valuable products. Moreover, microalgae can be used as a basis for creating a range of useful substances, including biodiesel. Vegetable and animal oils are the source of biodiesel today, but these feedstocks cannot fully replace traditional diesel fuel due to the large land resources required for growing oilseeds. Biodiesel is considered a renewable fuel because it can be produced by converting oils. Microalgae convert carbon dioxide and, in some countries, are the only source of biodiesel fuel with the potential to completely replace fossil fuels. This article reviews and analyzes global experience using microalgae to absorb CO2, with potential for using microalgae biomass to produce biodiesel. The undeniable potential of microalgae as a promising technology for significantly reducing greenhouse gas emissions from industrial flue gases is substantiated. Microalgal lipids represent a promising feedstock for biodiesel production in the transportation sector. However, successful implementation of this technology requires comprehensive evaluation of cultivation parameters, including flue gas composition, temperature regimes, and selection of appropriate microalgal strains. An economic assessment of biodiesel production from microalgae biomass is presented, demonstrating the feasibility of producing biodiesel from biomass cultivated on a large scale.
Section: Methodology and research methods. Models and forecasts
Results of analysis of various water samples (drinking water, wastewater, and treated wastewater) for anionic surfactants content are presented. The study was conducted using high-performance liquid chromatography with mass spectrometric detection. A comprehensive analytical methodology, including simplified sample preparation, gradient chromatographic separation, mass-spectrometric detection in various modes (including tandem mass spectrometry) is described. Special attention is paid to the anionic surfactants identification using open-access mass-spectrometric databases that based on molecular mass and characteristic fragments. An example of assessing the quantitative composition of contaminants in wastewater before and after treatment is given. It demonstrates the effectiveness of the applied approach. The results of the chromatographic analysis of the wastewater sample revealed anionic surfactants – alkyl-benzene sulfonates (C10-, C11-, and C12-) and alkylsulfates (C14). After wastewater treatment, the concentration of the above substances significantly decreases; a removal efficiency is 97–99 %. The detection of trace amounts of surfactants in the treated water indicates the need for continuous water quality monitoring to assess the level of contamination by anionic surfactants.
Keywords: anionic surfactants, mass spectrometry, chromatography, wastewater
Article published in number 2 for 2026 DOI: 10.25750/1995-4301-2026-2-040-047
Views: 9
Study of cobalt ions’ sorption from water by Lissachatina fulica shell
N.A. Voronin, V.A. Somin
Section: Population ecology
Cobalt compounds are among the most toxic pollutants of water bodies that can enter them due to discharges of insufficiently treated wastewater from engineering and chemical industries. In the environment cobalt accumulates in plant and animal tissues and can enter the human body through the trophic chain, causing toxic and mutagenic effects. In this regard, it is important to use technologies that effectively extract cobalt from water using various materials. This paper presents the results of studies on the cobalt sorption from water by the shell of the Lissachatina fulica (Férussac, 1821) mollusk. For the research, a shell with geometric dimensions from 2 to 5 mm, pre-washed and crushed on a jaw crusher, was used both in its native form and modified with a sodium hydroxide solution with a concentration of 10 % and treated with ultrasound at a frequency of 40 kHz. A static sorption capacity was determined for all materials, which was 37 mg/g for native material, 31 mg/g modified with sodium hydroxide, and 17 mg/g modified with ultrasound. Linearized isotherms of sorption of cobalt ions are constructed according to the Langmuir, Freundlich, Dubinin-Radzhdankevich, and Temkin models. The sorption equilibrium constants and the values of the limiting sorption are calculated according to these models. It is revealed that the sorption of cobalt ions is satisfactorily described by the Langmuir, Freundlich, and Temkin models for both native and modified shells and has a physical character. The Dubinin-Radostkevich model is not suitable for describing the sorption of the studied materials, since the correlation coefficient was less than 0.2. Activation with sodium hydroxide and ultrasound is impractical, since it leads to a decrease in the sorption capacity of the material by 1.2 and 2.2 times, respectively.
Keywords: adsorption, cobalt ions, shellfish, water pollution
Article published in number 2 for 2026 DOI: 10.25750/1995-4301-2026-2-210-218
Views: 3
Monitoring of small mammals’ communities in natural and disturbed biotopes in the Central Caucasus foothills
L.H. Shugusheva, M.S. Gudova, M.M. Emkuzheva
Section: Monitoring of natural and anthropogenically disturbed areas
The development of horticulture in the region, including intensive and super-intensive technologies, as well as the activities of hydrometallurgical plant in the city-resort of Nalchik lead to an increase in anthropogenic impact on the ecosystems in the Central Caucasus foothills. It is shown that the species composition, species ratio, and community structure of Micromammalia depend on the degree of anthropogenic load. In the theriofauna we distinguished three species groups. Sorex satunini Ognev, 1922, and Micromys minutus Pallas, 1771, inhabit exclusively natural habitats. Crocidura suaveolens Pallas, 1811, Mus musculus Linnaeus,1758, Dryomys nitedula Pallas, 1778, Cricetus cricetus Linnaeus,1758, and Microtus arvalis Pallas, 1778, inhabit disturbed ecosystems. Apodemus uralensis Pallas, 1811, Apodemus agrarius Pallas, 1773, and Terricola majori Thomas, 1906, inhabit both disturbed and natural habitats. Apodemus uralensis is the dominant eurybiont, which reaches its maximum share in the community in highly modified landscapes, forming stable populations. The field mouse is a subdominant species, with maximum contribution to the community in slightly disturbed biotopes. At the same time, it gravitates to natural landscapes, reaching high abundance there. Rich species diversity and minimal dominance index are characteristic of communities of weakly disturbed biotopes. On the contrary, the theriocomplex of highly disturbed habitats has the maximum dominance index and minimal equalization index, with maximum equalization in the therio-population of Micromammalia in natural ecosystems. The greatest similarity was noted between the communities of weakly and highly disturbed habitats, converging them are: Apodemus uralensis, Apodemus agrarius, Dryomys nitedula, Microtus arvalis and Crocidura suaveolens.
Keywords: monitoring, small mammals, biodiversity, community
Article published in number 2 for 2026 DOI: 10.25750/1995-4301-2026-2-083-091
Views: 4
Bioaccumulation and biochemical effects of diesel on Mediterranean mussel Mytilus galloprovincialis Lamarck, 1819
Petroleum hydrocarbons’ pollution of the aquatic environment is a serious ecological problem. This requires a detailed study of their accumulation in the tissues of aquatic organisms and identification of informative biomarkers to assess the animals’ functional state under oil pollution. The aim of the work was to study diesel (DF) effect on the bioaccumulation, prooxidant-antioxidant system (level of oxidized proteins and lipid peroxidation, antioxidant enzyme (superoxide dismutase (SOD), catalase (CAT) activities) and aminotransferase (aspartate aminotransferase, alanine aminotransferase) activities in the Mytilus galloprovincialis hepatopancreas after five days’ experiment. It was shown that hydrocarbon content in mussels’ hepatopancreas in the control, I (0.5 mg/L DF) and II (1 mg/L DF) experimental groups were 0.01, 0.10 and 1.43 mg/g dry weight, respectively. The level of lipid peroxidation in I and II experimental groups was significantly higher (+59 % and +95 %, respectively) as compared to the control (p < 0.05). The levels of neutral aldehydes from both experimental groups and basic aldehydes from II group significantly increased (+59 %, +47 %, 52 %, respectively) as compared to the control (p < 0.05). SOD activity in II group mussels was significantly higher compared to the control (+30 %) and I group (+45 %) (p < 0.05). Contrastingly, CAT activity in II group mollusks was significantly lower as compared to the control (–125 %) and I group (–114 %) (p < 0.05). Aminotransferase activities did not differ in the control and the experimental groups. Thus, it was determined, that parameters of prooxidanta-ntioxidant system demonstrate high sensitivity to DF and can be used as biomarkers for assessing the functional state of mollusks in oil polluted environment.
Keywords: diesel, mussel Mytilus galloprovincialis, hepatopancreas, parameters of prooxidant-antioxidant system, activity of aminotransferases
Article published in number 2 for 2026 DOI: 10.25750/1995-4301-2026-2-165-173
Views: 4
Soil respiratory activity and oil products degradation when adding granulated sewage sludge
Oil contamination of soils is one of the most serious environmental problems that require developing effective and cost-efficient remediation methods. Biological approaches, particularly bioremediation using organic ameliorants, are of special interest as they can activate the indigenous microflora and accelerate pollutant degradation. One promising material for the bioremediation of oil-contaminated soils is thermally treated granulated sewage sludge (granulate). It contains microorganisms, organic matter, and biogenic elements, which warrants an assessment of its efficacy in the remediation of oil-polluted soils. A model experiment was conducted for the first time studying the granulate effect on the remediation parameters of an oil-contaminated grey forest soil. These parameters included respiratory activity, the eco-physiological status of the microbial pool, and the efficiency of total petroleum hydrocarbon (TPH) degradation. The research encompassed three remediation approaches: technological, microbiological, and phyto-microbiological. The study established that 2 % and 4 % granulate application significantly enhanced both the basal and substrateinduced respiration of the contaminated soil. The maximum CO2 emission was observed in the phyto-microbiological remediation trials with 4 % granulate. It was shown that the use of granulate in samples with low TPH content (up to 3.7 g/kg) did not intensify their degradation. The highest TPH degradation efficiency (a 69–79 % reduction from the initial content) was achieved at a contaminant concentration of 4.4–15.4 g/kg in the microbiological remediation experiment with 2 % granulate. We conclude that the application of 2 % granulated sewage sludge provides an optimal “degradation efficiency / CO2 emission” ratio for soils with a TPH content exceeding 3.7 g/kg. This leads to maximum pollutant breakdown with a minimal increase in carbon dioxide emissions. The cultivation of higher plants did not yield a significant additional effect, indicating the promise of applying the technologically simpler microbiological approach with 2 % granulate for the remediation of oil-contaminated soils.
Section: Chemistry of natural environments and objects
Tetrazolium salts are used in monitoring the ecological state of environmental objects, especially after exposure to factors unfavorable to organisms: forest fires, oil spills, industrial and household pollution. The possibility of identifying the indicator properties of iodinitrotetrazolium chloride (INT) to assess the viability of the aerobic bacterium Bacillus stearothermophilus is shown. The dependence of the concentration of the iodomonoformazane (IMF) reduction product on the exposure time at an optimal for the vital microorganisms’ activity temperature of 37 оC was studied as a criterion for quantifying the bacterium reducing ability in relation to a tetrazolium salt. The IMF concentration was determined spectrophotometrically at 490 nm wavelength after extraction of an aliquot of the reaction mixture with ethyl acetate. It was found that the reaction rate slows down when the reagent conversion reaches 60–70 %. It has been suggested that a decrease in the regenerative capacity of bacterial cells may be due to the IMF recovery product inhibitory effect. Formazane is less polar than INT, and has a greater affinity for cellular components. This argument suggests that IMF forms inactive complexes with cellular reducing agents. The blocking of cellular redox centers by the reduction product may be the main reason for the decrease in reagent conversion over time. A formal kinetic scheme of the IMF reduction reaction by cellular electron donors is proposed based on experimental data on the dependence of the IMF current concentration on the exposure time. According to the scheme, the reaction product does not selectively interact with cellular redox centers to form inactive complexes with an inhibition constant Ki. The scheme is processed by the diagram method based on the quasi-equilibrium approximation of kinetic scheme analysis. The integral kinetic equation in Walker-Schmidt coordinates, which are widely used in enzymatic catalysis, is obtained by the diagram method. The kinetic equation obtained is consistent with the experimental data. The numerical value of the inhibition constant by the product equal to (1.42 ± 0.12) . 10-5 M was determined.
Keywords: iodonitrotetrazolium chloride, Bacillus stearothermophilus, kinetic scheme of inhibition by the reaction product, diagram method, inhibition constant
Article published in number 2 for 2026 DOI: 10.25750/1995-4301-2026-2-137-144
ISSN 1995-4301
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