ГлавнаяENAquatic Bioresources & Environment. Volume 5, Number 2, 2022

Aquatic Bioresources & Environment. Volume 5, Number 2, 2022

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Environmental Concerns and the State of Aquatic Environment

Assessment of the water quality of the Don River downstream from its confluence with the Temernik River based on the saprobity index and bioassay data
M.A.B. Al-Ghizzi , E.N. Bakaeva
Abstract. The Don River is one of the largest rivers in the East European Plain. The right tributary of the Don River—the Temernik River—flows through the metropolis of Rostov-on-Don and affects the water quality of the main watercourse. This study was aimed at the assessment of the organic pollution and toxicity of water in two horizons (0.3 and 9.0 m) of the Don River downstream from its confluence with the Temernik River using the saprobic index S and biotesting. Observations were carried out for 7 months in 2019. The data on the quality of the Don River water have been obtained from the combined results of two biological methods for the first time. The dynamics of changes in the quality of the river water in the course of 7 months is presented. The samples for the investigation were collected сoncurrently. Comparison of the water quality in two horizons (surface and deep) of the river section based on the data obtained using two biological methods has been conducted for the first time. The saprobity results for the phytoplankton indicated the presence of organic water pollution at both levels of the Don River during all 7 months of the study. The saprobity index values ranged from 2.0 to 3.6. Water quality was characterized as ranging from moderately polluted to polluted. This corresponds to α-β-mesosaprobic level. The maximum level of organic pollution according to the saprobity index was recorded in September for both horizons. Saprobity increases with an increase in the proportion of blue-green algae in the phytocenosis. The relative abundance of blue-green algae ranged from 45.83 to 77.77 %. The surface horizon had higher organic pollution during the warm period (May–September), and for the deep horizon it was higher during the cold period (April, October, and November). The toxic effect of the river water was manifested in the inhibition of the growth of Chlorella vulgaris. Water toxicity over the investigated period (7 months) was inconsistent. In each season, it only appeared for one month. Water toxicity at the both horizons was recorded in spring (April), summer (August), and autumn (November). High saprobity and toxic effect of the water did not always coincide. The concurrent presence of these characteristics is typical for the deep horizon. Toxicity fluctuations are apparently associated with the temporal pattern of the Temernik River pollution by the metropolis waste
waters and with the measures for the Temernik River improvement taken by the municipal authorities.
Keywords: phytoplankton, saprobity index S, organic pollution, bioassay, toxicity, Don River, Temernik River, water horizon
Assessment of the physicochemical properties of the Halda River, Bangladesh.
Md.S. Islam , M.A. Azadi , M. Nasiruddin , Md.T. Islam , D. Akter , T.U. Ahmed
Abstract: Water quality in any water body is dependent on its physicochemical properties, the knowledge of which is necessary to maintain the suitability of the environment for aquatic organisms. In Bangladesh, the Halda River, a valuable spawning ground for the Indian major carp species is currently believed to be under threat due to anthropogenic and environmental causes. To identify the physicochemical properties of this river, eleven physical and chemical parameters were under investigation for 24 months, from January, 2017 to December, 2018, at three selected stations on the river. The average and range values of the investigated parameters were: 27.70±1.25 °C and 22.52–30.77 °C for water temperature, 24.96±6.11 cm and 15.33–35.33 cm for transparency, 114.36±14.42 µS/cm and 54.67–162.17 µS/cm for electrical conductivity (EC), 50±10 ppm and 30–70 ppm for total dissolved solids (TDS), 7.46±0.14 and 7.1–7.7 for pH,   6.17±0.88 mg/L and 4.30–10.07 mg/L for dissolved oxygen (DO), 13.14±2.41 mg/L and 7.49–43.29 mg/L for free carbon dioxide (fCO ), 7.71±1.15 mg/L and 4.41–11.62 mg/L for calcium (Ca++), 32.76±5.17 mg/L and 17.83–46.33 mg/L for total hardness (TH), 47.10±12.47 mg/L and 36.17–55 mg/L for total alkalinity (TA), and 1.38±0.38 mg/L and 0.72–2.43 mg/L for biochemical oxygen demand (BOD5). Significant positive relationships between transparency and EC (r=0.78, P<0.01), EC and TH (r=0.96, P<0.001), EC and TDS (r=0.92, P<0.001), EC and Ca++(r=0.87, P<0.001), TDS and TH (r=0.86, P<0.001), Ca++ and TH (r=0.87, P<0.001), and Ca++ and TDS (r=0.86, P<0.001) have been observed. Physicochemical properties indicated that the level of pollution of the Halda River water was low, which made it suitable for aquatic organisms and acceptable for domestic and agricultural purposes.Keywords: physicochemical parameters, pollution, water quality, monthly and seasonal   variation, Halda River

Biology and Ecology of Aquatic Organisms


Evaluation of so-iuy mullet tissues toxicity using whole-cell bacterial luminescent sensors
A.A.K. Al-Rammahi , M.A. Sazykina , BT.O. arabashin , M.V. Klimova, Sh.K. Karchava, M.I. Khammami , I.S. Sazykin
Abstract. Contamination of aquatic organisms with pollutants leads to depletion of genetic resources, both due to a decrease in the number of species, and to degradation of their gene pools caused by accumulation of the changes in   genetic   parameters. In this regard, ecotoxicological studies are important   both in terms of predicting the fish state and in relation to the state and the bioresource potential of the investigated water body. This paper presents the results of ecotoxicological assessment of various tissues of the so- iuy mullet (Planiliza haematocheilus (Temminck & Schlegel, 1845)), living in the Azov Sea, obtained by biotesting based on whole-cell luminescent bacterial sensors (E. coli MG1655 (pAlkA-lux), E. coli MG1655 (pRecA-lux), E. coli MG1655 (pKatG-lux), and E. coli MG1655 (pSoxS-lux)).   It has been shown   that liver, gills and muscle tissue of so-iuy mullet can serve as analytical samples for monitoring the toxicity of aquatic ecosystems. In the majority of the investigated tissue samples of so-iuy mullet, toxic effects, induced by the presence of DNA-tropic agents and prooxidants, have been found. In has been shown that the gills and liver are much more susceptible to the toxic effects of pollutants than the muscle tissue. The obtained results indicate the negative impact of anthropogenic activities on this fish population and may be useful for assessing the ecotoxicological characteristics of aquatic ecosystems.
Keywords: Azov Sea, fish,  liver, gills, muscle tissue, toxicity, lux biosensors

Dynamics of quantitative development of spring and summer zooplankton in the Krasnodar Reservoir
G.S. Kornienko, T.V. Chayka
Abstract.
This paper presents information on the quantitative development and species composition of the spring and summer zooplankton of the Krasnodar Reservoir in 2019, as well as long-term changes in the abundance and biomass of zooplankton for two seasons (spring and summer). The data on the changes in species diversity and quantitative development of zooplankton during   the reservoir   filling period and   25 and 45   years onward are presented. The dominant groups of zooplankters and dominant species among them have been identified. A comparison of the dynamics of qualitative and quantitative development of zooplankton in the Krasnodar Reservoir has shown that for the past 25 and 45 years (from 1974 to 2019), changes in species composition were insignificant. The number of species of planktonic organisms in each period under review is almost the same: 42 species during the reservoir filling period and 45 species in 1999–2001 and 2019. In terms of their abundance, rotifers and copepods prevailed in the present plankton composition, accounting for 57.3 and 40.7 %, respectively. Copepods accounted for 80.1 % of the total biomass. The average abundance of zooplankton organisms in the spring and summer seasons of 2019 exceeded the count for the period after flooding by 1.4 times, and for 1999–2001 it was by 2 times. However, the biomass of zooplankton in previous years was, on average, 3.5 and 8 times higher, respectively, due to the development of larger forms of cladocerans and copepods. The biomass of spring and summer zooplankton in the Krasnodar Reservoir in 2019 was 0.21−0.34 g/m3, which is compliant with the values characteristic for mesotrophic reservoirs. It is concluded that the Krasnodar Reservoir is a water body that has preserved its fishery potential for growing fish on natural feed resources.
Keywords: Krasnodar Reservoir, zooplankton, biomass, abundance, species diversity

Shallow-water taxocene of Gastropoda on soft bottoms in some areas along the Crimean coast (the Black Sea)
M.V. Makarov
Abstract.
This paper summarizes our own data on the spatial and temporal distribution of species composition, abundance, biomass and trophic structure of gastropod mollusсs in the shallow-water (0–9 m, mostly up to 5 m in depth) areas along the Black Sea Crimean coast from Karkinit Bay in the northern part of the Crimean Peninsula to Laspi Bay in its South Coast. Over the period spanning from 2001 to 2020, 441 benthic samples were taken at 7 sites in sandy silt biotopes. A total of 31 species was recorded with a maximum (22 species) in Kruglaya (Round) Bay. However, only one species, Bittium reticulatum, was found in all of the investigated areas. The highest abundance (4,243±253 ind./m2) was recorded in the area covering the estuary of Chernaya (Black) River and the head of Sevastopol Bay, and the highest biomass (5.3±0.2 g/m2) was observed in Kazachya (Cossacks) Bay. By these parameters, Hydrobia acuta prevailed. The maximum abundance and biomass of gastropod molluscs in the investigated areas were characteristic of the spring and summer seasons, when the reproduction of the majority of species occurs. The trophic structure of Gastropoda taxocene was very diverse and represented by the following groups: detritivores, scavengers, polyphages, phytophages, predators, ectoparasites, and others (species with unknown type of feeding). In terms of the number of species, phytophages dominated (11 species); detritophages (1,045 ind./ m2) dominated in terms of abundance, and scavengers (1.13 g/m2) were dominant by biomass.
Keywords: distribution, species, abundance, biomass, substrate, depth, season, trophic characterization

Ichthyofauna of Marine and Inland Water Bodies


Dynamics of the state of the Azov and Black Sea population of the European anchovy (Engraulis encrasicolus Linnaeus, 1758) off the coasts of Abkhazia during the winter migration season in 2011–2021
R.S. Dbar , P.D. Gamakhariya
Abstract. Based on the available data for a ten-year period (2011–2021), the ecological structure and morphobiological composition of the European anchovy (Engraulis encrasicolus L., 1758) population wintering in the coastal waters of Abkhazia have been analyzed. This work is of considerable theoretical and practical value for the fishing industry, since it allows for interpretation of the dynamics of anchovy populations wintering off the coasts of Abkhazia. This work is aimed at the intraspecific analysis of the population characteristics of the European anchovy inhabiting the Azov and Black Seas. To obtain the necessary information, standard methods for collecting and processing ichthyological material were used. Following the data collected in the course of the monitoring during the investigated period, the dynamics of the length and age composition of catches has been considered, and the intra-annual and inter-annual patterns in the anchovy fishing (Black Sea and Azov Sea stocks) are presented. The cyclical nature of the change in its stocks has been revealed, and the changes in population characteristics as evidenced by the composition of catches and the spatial distribution of wintering anchovy aggregations in the Abkhazian waters of the Black Sea have been recorded. The absolute values of catches and their long-term fluctuations are given. This research provided the data characterizing the status of the Azov and Black Sea population of the European anchovy during its wintering season as dynamically stable with a tendency for stock reduction and the decrease in the number of fish individuals exceeding the minimum landing size.
Keywords: European anchovy, morphobiological composition, size–age structure, cyclic stock changes, fishing dynamics, Abkhazia
Genetic polymorphism of the sterlet (Acipenser ruthenus) living in natural conditions and grown in the fish farm environment
I.A. Kotov , O.V. Trofimov , I.V. Pak, A.I. Shanskikh
Abstract. This work is aimed at a comparative assessment of genetic polymorphism of the sterlet population inhabiting the Irtysh River (Uvatsky District, Tyumen Region) and the broodstock of the hatchery “Era” (“Epoch”) (RAS, recirculating aquaculture systems, Tyumen) based on microsatellite markers. The sterlet broodstock was comprised of the offspring from mature individuals caught in the Irtysh River and used for artificial reproduction. Polymorphism has been investigated for three primers: CR–212, CR–215, and X–9. It has been shown that the indicators of genetic diversity—polymorphism, heterozygosity, the number of active and effective alleles—change in the fish reared in the RAS environment. A decrease in the share of polymorphic markers for the primer CR–212 and in heterozygosity by 1.38 times have been recorded for the sterlet from the broodstock as compared to the sterlet from a natural population inhabiting the Irtysh River. A decrease in the number of active and effective alleles in the sterlet cultivated in the RAS environment has been discovered. The observed phenomenon may result from artificial reproduction of the fish, its prior selection, or genetic drift. This paper also provides a comparative assessment of genetic polymorphism of the stelet from the Kama and Irtysh Rivers based on the data collected by its authors and by other researchers.
Keywords: sterlet, natural population, broodstock, ISSR-PCR markers, polymorphism, heterozygosity
Morphology and fluctuating asymmetry of sagittal otoliths of the black scorpionfish Scorpaena porcus Linnaeus, 1758 (Pisces: Scorpaenidae) from the Caucasian and Crimean Shelves of the Black Sea
 A.A. Polin , A.N. Pashkov , T.V. Denisova
Abstract.
Currently, the method of otolithometry is widely used as a tool for studying the population structure and differentiation of populations of various fish species. At the same time, scientific literature contains only fragmentary data on the otolith morphology of the black scorpionfish Scorpaena porcus, a spicies common to the Black Sea coastal fish communities. This work was aimed at the investigation of the morphology of sagittal otoliths of the black scorpionfish inhabiting the Caucasian and Crimean shelves of the Black Sea, as a means for studying its population structure. The morphology of sagittal otoliths of the black scorpionfish from six areas—“Bolshoy Utrish”, “Gelendzhik”, “Magri”, “Adler”, “Sevastopol”, and “Feodosia”—is described in this paper. A positive correlation between the body length of black scorpionfish and the length of its otoliths was found in all investigated areas. The level of difference (similarity) in the morphology of otoliths has been analysed. The degree of fluctuating asymmetry has been estimated based on differences between the values of the morphological features of the right and left otoliths.
Keywords: black scorpionfish, sagittal otoliths, Black Sea, Caucasian shelf, Crimean shelf, otolith morphology, fluctuating asimmetry

Aquaculture and Methods of Artificial Reproduction


Experience of the rearing of so-iuy mullet Planiliza haematocheila fingerlings in polyculture with the European carp Cyprinus carpio in freshwater ponds
E.V. Gorbenko , A.A. Pavlyuk , S.G. Sergeeva, M.A. Grinchenko , A.P. Nagornaya
Abstract. The results of the experiment on the rearing of so-iuy mullet fingerlings in polyculture with the European carp in the ponds with decreased mineralization, which has been conducted at the facilities of Rogozhkino Fish Farm, are presented. The so-iuy mullet juveniles were obtained artificially in a hatchery of the research facility “Zavetnoe” and reared on artificial feeds of two different formulations. In the first mode of rearing, the average weight of juveniles was 1.68 g, and in the second one it was 3.49 g. At the further stages, the juveniles were separated into different ponds based on the feeding mode. The juveniles in these ponds were reared under the controlled hydrochemical and hydrobiological conditions. The species composition of the zooplankton community was typical for pond ecosystems. In the experimental ponds, the biomass of the zooplankton on which the juveniles fed was low—2.2 g/m3 on average. Dietary analysis of the so-iuy mullet juveniles has shown that the detritus content in a food bolus was no less than 30 %. The dynamics of cultivation, biological, physiological, and biochemical parameters of the juveniles have been identified for different modes of rearing. The result obtained with the first mode of rearing was positive; growth characteristics and physiological status of the juveniles were on the normal level for the individuals of such age growing in natural water bodies. The quality and growth rate of the so-iuy mullet juveniles reared in the second mode were satisfactory; total lipid content in the tissues was relatively low. These results reveal the possibility of rearing healthy so-iuy mullet juveniles in fresh water. It is conducive to stock the freshwater bodies with the fingerlings which weight does not exceed 3–4 g; the juveniles of higher weight gain reared on artificial feeds adapt to the aquatic environment of a water body after their transition to the natural feed considerably longer.
Keywords: so-iuy mullet Planiliza haematocheila, European carp Cyprinus carpio, artificial feed, fodder zooplankton, rearing, growth rate, physiological status

Informational Messages


On the announcement of the International Research and Practice Conference, dedicated to the 100th anniversary of “YugNIRO”, held on September 19–21, 2022