Marine Biological Journal <p>Морской биологический журнал Marine Biological Journal.</p> <div><em><strong>Launched in February 2016.</strong></em></div> <div><em><strong>Certificates of registration:</strong></em></div> <div>print version: <a href="" target="_blank" rel="noopener">ПИ № ФС 77 - 76872 of 24.09.2019</a>,</div> <div>online version: <a href="" target="_blank" rel="noopener">ЭЛ № ФС 77 - 76873 of 24.09.2019</a>.</div> <div> <div><em><strong>Founder:</strong></em></div> <div>A.&nbsp;O.&nbsp;Kovalevsky Institute of Biology of the Southern Seas of&nbsp;RAS.</div> </div> <div><em><strong>Publishers</strong></em>:</div> <div><a href="" target="_blank" rel="noopener">A.&nbsp;O.&nbsp;Kovalevsky Institute of Biology of the Southern Seas of&nbsp;RAS</a>,</div> <div><a href="" target="_blank" rel="noopener">Zoological Institute of&nbsp;RAS</a>.</div> <div>ISSN 2499-9768 print, ISSN 2499-9776 online.</div> <div><em><strong>Languages:&nbsp;</strong></em>Russian, English.</div> <div><em><strong>Periodicity:</strong></em> four issues a&nbsp;year.</div> <div>&nbsp;</div> <div><strong>Authors do&nbsp;not need to&nbsp;pay an&nbsp;article-processing charge.</strong></div> <div>The payment of&nbsp;royalties is&nbsp;not&nbsp;provided.</div> <div>&nbsp;</div> <div>Author recieves one copy of&nbsp;printed version of&nbsp;the journal as&nbsp;well as&nbsp;.pdf file.</div> <div>&nbsp;</div> <div> <div class="siteorigin-widget-tinymce textwidget"> <p>Marine Biological Journal is&nbsp;an&nbsp;open access, peer reviewed (double-blind) journal. The journal publishes original&nbsp;articles as&nbsp;well as&nbsp;reviews and brief reports and notes focused on new data of&nbsp;theoretical and experimental research in&nbsp;the fields of&nbsp;marine biology, diversity of&nbsp;marine organisms and their populations and communities, patterns of&nbsp;distribution of&nbsp;animals and plants in&nbsp;the World Ocean, the&nbsp;results of&nbsp;a&nbsp;comprehensive studies of&nbsp;marine and oceanic ecosystems, anthropogenic impact on&nbsp;marine organisms and on&nbsp;the ecosystems.</p> <p>Intended audience: biologists, hydrobiologists, ecologists, radiobiologists, biophysicists, oceanologists, geographers, scientists of other related specialties, graduate students, and students of&nbsp;relevant scientific profiles.</p> <p>The subscription index in&nbsp;the “<a title="Russian Press MBJ" href="" target="_blank" rel="noopener">Russian Press</a>” catalogue is Е38872.</p> </div> </div> A. O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Sevastopol, Russian Federation en-US Marine Biological Journal 2499-9768 Transfer of free methane by gas bubble streams from anaerobic to aerobic waters of the Black Sea <p>“Breath of earth” in the form of methane gas bubble streams from a seabed (methane seeps, bubble emanations) is a planetary phenomenon that was noticed only at the end of the XX century. The study of this phenomenon, being an important link in processes of lithosphere, hydrosphere, atmosphere, and biosphere interaction, is relevant to date. In this work, methane fluxes were determined in the known area of intense methane occurrences of biogenic nature, geographically tied to Dnieper River paleochannel in the northwest of the Black Sea. Bubbling (free) methane flux from anaerobic to aerobic waters in the active methane seeps area of Dnieper River paleochannel in the depth range of 140–725 m is estimated averagely as 1.2·10³ m³·km<sup>−2</sup>·year<sup>−1</sup> (STP), or 2.8 % of bubbling methane emitted from a seabed. The value of the investigated flux was 4.2 % of the specific flux of bubbling methane to a water column on shelf depths (less than 140 m) in the same area. Methane flux estimate, obtained in this work, seems to be a significant environmental factor in conditions of strong stratification of Black Sea waters, where methane transfer by gas bubble streams is the main mechanism for introducing deep-water methane into biogeochemical cycles and carbon transformation processes of Black Sea aerobic zone.</p> Yu. G. Artemov Copyright (c) 2020 A. O. Kovalevsky Institute of Biology of the Southern Seas of RAS 2020-09-30 2020-09-30 5 3 4 10 10.21072/mbj.2020.05.3.01 Baromembrane method for analysis of ultra-low concentrations of radionuclides in water samples <p>This paper demonstrates the use of the baromembrane method for measuring ultra-low concentrations of radionuclides in water of freshwater reservoirs. The relevance is due to the need to determine radionuclides introduction into water cooling ponds used by enterprises of nuclear fuel cycle. Radionuclides of natural and technogenic origin, not associated with enterprise discharge, are always present in water cooling ponds, forming a natural or technogenic altered background. Its presence often makes it difficult to identify contribution of enterprise’s discharge to water activity, since routine monitoring methods are characterized by a very high detection limit for radionuclides. Traditional methods for determining background radionuclides concentrations require sampling of at least 500 L of water, followed by their evaporation to get a dry residue. This procedure takes at least 5 days. It is possible to reduce time and energy spent on vaporizing hundreds of liters of water by pre-concentrating radionuclides in a smaller sample volume with the baromembrane method. To demonstrate this method, a portable installation with osmotic membranes was used being characterized with initial productivity of 6.0 L·min<sup>−1</sup>. The osmotic membranes separate source water sample into two components: demineralized permeate and concentrate, containing radioactive substances. This method allows preliminary concentration of water samples from 500 to 20 L in 10–15 hours with minimal losses of radionuclides (time period depends on water mineralization level). The method is universal; it can be used for concentration of dissolved salts of any heavy metals and other organic compounds. It allows preparation of water countable samples in much shorter time that traditional method (evaporation).</p> M. E. Vasyanovich A. A. Ekidin A. V. Trapeznikov A. P. Plataev Copyright (c) 2020 A. O. Kovalevsky Institute of Biology of the Southern Seas of RAS 2020-09-30 2020-09-30 5 3 11 22 10.21072/mbj.2020.05.3.02 Molecular bases of the effect of low doses of radiation <p>By definition, low doses are minimum doses of a damaging agent, in particular radiation, causing a recorded biological effect. The problem of exposure to low doses of radiation is being discussed in scientific literature for decades, but there is still no generally accepted conclusion concerning the existence of some features of the effect of low doses in contrast to that of acute exposure. This is due to the fact as follows: if being fixed, these effects have a weak expression and can be easily criticized. The second important aspect of this problem is that biological effects are mainly described phenomenologically in literature, without deciphering their molecular causes. In recent years, a number of articles appeared in which the authors, when studying exposure to low doses of DNA-tropic agents, show that postreplication repair (in particular, its error-free branch) plays a key role in these effects. In the laboratory of eukaryotic genetics of Petersburg Nuclear Physics Institute named by B. P. Konstantinov, it was possible to isolate unique yeast mutants with a disrupted branch of error-free postreplication repair. A study of the processes of eliminating DNA damage with minimal deviations of their number from a spontaneous level made it possible to explain at the molecular level the differences in cell response to low doses from acute exposure.</p> V. G. Korolev Copyright (c) 2020 A. O. Kovalevsky Institute of Biology of the Southern Seas of RAS 2020-09-30 2020-09-30 5 3 23 29 10.21072/mbj.2020.05.3.03 Comprehensive radioecological monitoring of freshwater ecosystems in the vicinity of Rooppur NPP (People's Republic of Bangladesh) <p>The paper presents experience of developing and maintaining a system of radioecological monitoring of freshwater ecosystems in the vicinity of Rooppur Nuclear Power Plant (Bangladesh). Components of freshwater ecosystems in the zone of NPP impact are both very informative for determining the environmental state and very important for conducting economic activities. Therefore, the issue of assessing and predicting quality of freshwater ecosystems in the vicinity of NPP is relevant for ensuring radiation and environmental safety. During the studies, we developed a detailed monitoring program; selected observation points for the state of surface water and groundwater at different distances from Rooppur NPP; determined monitoring objects (water, bottom sediments, higher aquatic vegetation, and fish), list of parameters to be studied, observation regulation, methods, and regulatory and technical support. Among the indicators controlled we considered the following ones: physicochemical properties of water and bottom sediments; radionuclide content of components of freshwater ecosystems including natural (<sup><sup>40</sup></sup>K, <sup><sup>226</sup></sup>Ra, and <sup><sup>232</sup></sup>Th) and technogenic (<sup><sup>90</sup></sup>Sr, <sup><sup>137</sup></sup>Cs, and <sup><sup>3</sup></sup>H) radionuclides; and content of 19 heavy metals, as well as chemical pollutants. Monitoring studies were conducted in 2014–2017, considering climatic peculiarities of the region at different periods of the year. Radionuclides in environmental objects were determined by spectrometry and radiochemistry; heavy metals – by atomic absorption and plasma emission analysis methods. It was established that higher aquatic vegetation in the Padma River is found not in all seasons. In December, it was almost absent. The maximum species diversity was registered in June. Differences between surface water and groundwater in the vicinity of Rooppur NPP were distinguished for several physical and chemical characteristics. Values of drinking water total mineralization and hardness were higher than that of surface water by 2–3 times. This is due to Padma River water composition, the basis of which is meltwater and rainwater. Organic pollutants content in surface water and groundwater was below detection limits or at minimum ones (benzopyrene – less than 0.01 μg·L<sup><sup>−1</sup></sup>; phenols – 1.3–3.5 μg·L<sup><sup>−1</sup></sup>; and petroleum products – 0.01–0.043 mg·L<sup><sup>−1</sup></sup>). Activity concentration of <sup><sup>137</sup></sup>Cs in Padma River water did not exceed 0.18 Bq·L<sup><sup>−1</sup></sup> (with a mean of 0.07 Bq·L<sup><sup>−1</sup></sup>) during the observation period. The content of <sup><sup>90</sup></sup>Sr was 0.02–0.12 Bq·L<sup><sup>−1</sup></sup>, and the concentration of <sup><sup>3</sup></sup>H varied in the range of 0.8–2.1 Bq·L<sup><sup>−1</sup></sup>. Mean specific activity of <sup><sup>90</sup></sup>Sr in bottom sediments was 0.5–1.8 Bq·kg<sup><sup>−1</sup></sup>, and <sup><sup>137</sup></sup>Cs – 0.8–2.1 Bq·kg<sup><sup>−1</sup></sup>. Specific activity of <sup><sup>3</sup></sup>H in bottom sediments was less than 3 Bq·kg<sup><sup>−1</sup></sup>, except for 3 samples in 2017 (12–30 Bq·kg<sup><sup>−1</sup></sup>), which was most likely due to a local pollution. Specific activity of <sup><sup>90</sup></sup>Sr in higher aquatic vegetation was 0.4–3.9 Bq·kg<sup><sup>−1</sup></sup>, and <sup><sup>137</sup></sup>Cs – 0.4–1.0 Bq·kg<sup><sup>−1</sup></sup>. In drinking water, activity concentrations of radionuclides were as follows: <sup><sup>137</sup></sup>Cs – 0.03–0.27 Bq·L<sup><sup>−1</sup></sup>; <sup><sup>90</sup></sup>Sr – 0.01–0.16 Bq·L<sup><sup>−1</sup></sup>; <sup><sup>3</sup></sup>H – 0.4–1.2 Bq·L<sup><sup>−1</sup></sup>. Specific activity of <sup><sup>90</sup></sup>Sr in fish was 0.02–1.6 Bq·kg<sup><sup>−1</sup></sup>.The content of <sup><sup>137</sup></sup>Cs in fish was 0.26–0.3 Bq·kg<sup><sup>−1</sup></sup>. Analysis of monitoring data on heavy metal levels in components of freshwater ecosystems in the vicinity of Rooppur NPP showed that for a number of elements their increased concentrations were recorded, most of which belong to monsoon season. In Padma River surface water, a repeating increase in As, Cd, Mn, and Al concentrations was noted, and in bottom sediments – an increase in As, Cd, Ni, Co, and Zn content, which was associated with anthropogenic impact and increasing runoff of pollutants during monsoon rains. Repeatedly increased As and Mn concentrations were noted in drinking water of Rooppur NPP 30-km zone. In separate samples, there was an increase in Fe and Al content. This might be due to both natural peculiarities of the region (relatively high As content in aquifers) and the state of water supply systems. Obtained results and developed network of radioecological monitoring of freshwater ecosystems would make it possible to register a change in the situation and to identify impact of Rooppur NPP operation on human population and the environment.</p> R. A. Mikailova D. N. Kurbakov E. V. Sidorova I. V. Geshel N. V. Andreeva Yu. V. Sorokin A. V. Panov Copyright (c) 2020 A. O. Kovalevsky Institute of Biology of the Southern Seas of RAS 2020-09-30 2020-09-30 5 3 30 54 10.21072/mbj.2020.05.3.04 137Cs concentration in surface waters of Far Eastern seas: Results of expeditionary research in 2018 <p>Based on the results of expeditionary research carried out during the 82<sup>nd</sup> cruise of the RV “Akademik M. A. Lavrentyev” (01.06.2018–20.07.2018), the assessment of current levels of concentration activity of technogenic radionuclide <sup>137</sup>Cs in surface waters of Far Eastern seas is given. The studies were carried out in the northwestern part of the Sea of Japan, the southern part of the Sea of Okhotsk, the coastal waters of the Pacific Ocean near the Kamchatka Peninsula, and the western part of the Bering Sea. Activity of <sup>137</sup>Cs in seawater samples was determined by sorption method using two series-connected adsorbers with subsequent measurement of <sup>137</sup>Cs content <em>via</em> its gamma-emitting daughter radionuclide <sup>137m</sup>Ba. Sorption efficiency was assessed by the difference in activity on the first and second adsorbers. A comparative analysis of contamination levels of water areas studied was made. It was revealed that <sup>137</sup>Cs volumetric activity in surface water of the Sea of Japan varied from (2.9 ± 0.1) to (5.1 ± 0.3) Bq·m<sup>−3</sup>, in the Sea of Okhotsk – from (1.8 ± 0.1) to (2.3 ± 0.1) Bq·m<sup>−3</sup>, and in the Bering Sea – from (1.7 ± 0.1) to (3.1 ± 0.1) Bq·m<sup>−3</sup>. The maximum <sup>137</sup>Cs concentrations were registered in the Sea of Japan, which might be due to its isolation from other water areas and presence of secondary sources of radionuclide intake. In general, contamination of adjacent water areas is insignificant, and fluctuations in concentrations occur within technogenic isotopes global background in the marginal seas of the Pacific Ocean.</p> O. N. Miroshnichenko A. A. Paraskiv Copyright (c) 2020 A. O. Kovalevsky Institute of Biology of the Southern Seas of RAS 2020-09-30 2020-09-30 5 3 55 63 10.21072/mbj.2020.05.3.05 Adaptation of natural yeast strains to heavy metal and radionuclides salts <p>Ability of natural yeast strains to grow in conditions of high concentrations of heavy metal and radionuclides salts was studied. More than 500 strains were tested for resistance to salts of heavy metals (U, Cs, Sr, Ni, Ar, Cu, Cd, and Co) and to elevated temperature (t) (+37…+52 °C). Most of the strains tested were resistant to one or more selective factors. Combinations of (t, Cd, Cu, Co) and (Cd, Cu, Co) occurred with the highest frequencies: 36 and 26 %, respectively. Ability of isolated strains to grow in the presence of high concentrations of radioactive isotopes Cs and Ni and to bind them with high efficiency was established. The results showed the possibility of potential using of libraries of natural microorganisms for disposal of both radionuclides and heavy metals, which are the main pollutants of natural and anthropogenic objects, as well as the possibility of using of isolated and tested strains of microorganisms for concentrating metals from low-grade ores or mining industry waste. Phenotypes diversity revealed indicates probable existence of several mechanisms of resistance to high heavy metals concentrations.</p> V. P. Stepanova A. V. Suslov I. N. Suslova E. A. Sukhanova B. F. Yarovoy V. N. Verbenko Copyright (c) 2020 A. O. Kovalevsky Institute of Biology of the Southern Seas of RAS 2020-09-30 2020-09-30 5 3 64 73 10.21072/mbj.2020.05.3.06 Mercury accumulation in suspended matter of foam and water of the Black Sea <p>The ability of suspended matter to concentrate mercury may be the prevailing factor in Black Sea purification. As a result of sedimentation, suspended particles transport pollution from the surface layer of the water column and, as a consequence, can deposit them in bottom sediments, thus participating in self-purification of marine area. Suspended matter, as a dispersed phase of an aqueous medium, considered as a heterogeneous dispersed system, can be more saturated with mercury than water itself, as a dispersion medium. In this work, contribution of dissolved and suspended forms of mercury to its total content was determined, and concentrating ability of suspended matter relative to mercury, which affects biogeochemical self-purification of waters from mercury, was estimated. All water samples were separated into filtrate and suspension by filtration through nucleopore filters with a pore diameter of 0.45 μm. Measurements of mercury concentration were carried out using a Hiranuma-1 analyzer by the method of atomic absorption spectrophotometry. Concentration of dissolved mercury in water was determined per liter, while in suspended matter – per liter and per gram of dry weight. Prevalence of dissolved form of mercury was revealed regardless of the season, with its percentage varying from 66.3 to 85.8 % of total mercury concentration. Average content of suspended form varied in the range of 14.2–33.7 % of its total form. Values of the dry weight of suspended matter (m<sub>ss</sub>) varied from 0.1 to 15.0 mg·L<sup>−1</sup> over the entire period studied, and an accumulation coefficient of mercury in suspended matter (K<sub>ss</sub>) varied from n·10³ to n·10<sup>7</sup>. Significant contribution of suspended form of mercury in sea foam to its total content in stormy weather was established. With dry weight of suspended matter in seawater reaching 9.6 mg·L<sup>−1</sup>, the concentration of dissolved form of mercury reached 55 ng·L<sup>−1</sup>, and the concentration of suspended one reached 20 ng·L<sup>−1</sup>. In sea foam, the concentration of suspended sedimentary matter was of 895.2 mg·L<sup>−1</sup>; mercury concentration reached 200 ng·L<sup>−1</sup> in dissolved form and 260 ng·L<sup>−1</sup> in suspended one. Total mercury concentration in sea foam in this case exceeded the threshold limit value (100 ng·L<sup>−1</sup>) for seawater. The accumulation coefficient of mercury in suspended matter (K<sub>ss</sub>) was 3.8·10<sup>4</sup> for seawater and 1.5·10<sup>3</sup> for foam. Such distribution of mercury in sea suspension, foam, and water, as well as K<sub>ss</sub> values obtained, may indicate high significance of suspended matter in self-purification of marine area. At a low mercury content in water, the concentrating ability of suspended matter, characterized by relatively high values of its mercury accumulation coefficient, becomes a very significant factor in the sedimentation self-purification of waters from mercury; however, with an increase in water pollution with mercury, the effect of this factor decreases.</p> A. P. Stetsiuk Copyright (c) 2020 A. O. Kovalevsky Institute of Biology of the Southern Seas of RAS 2020-09-30 2020-09-30 5 3 74 84 10.21072/mbj.2020.05.3.07 Application of the G. G. Polikarpov conceptual model of chronic action zonality of ionizing irradiation doze rates to biosphere objects in applied hydrobiology <p>Evolution of the approach to assessing ionizing radiation effects on living organisms is briefly discussed in this paper. Using the example of Black Sea hydrobionts, possibility of applying the G. G. Polikarpov conceptual radiochemoecological model of chronic action zonality of ionizing irradiation dose rates in nature to assess ecological exposure of technogenic radioisotopes ionizing radiation on aquatic biota was shown. In applied hydrobiology, this model can serve as the basis for a complex approach in assessing aquatic biota ecological state and its prediction for a wide range of <sup>239,240</sup>Pu activity concentration in seawater. The necessity of combined use of biogeochemical and equidosimetric indicators of radionuclide behavior in a water area is emphasized. In particular, for predictive dosimetric assessments, it is important to take into account quantitative characteristics of accumulative ability of Black Sea hydrobionts and a type of radioelement biogeochemical behavior, reflecting peculiarities of plutonium biogeochemical migration in a marine ecosystem.</p> N. N. Tereshchenko Copyright (c) 2020 A. O. Kovalevsky Institute of Biology of the Southern Seas of RAS 2020-09-30 2020-09-30 5 3 85 100 10.21072/mbj.2020.05.3.08