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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Oil-oxidizing bacteria of Zaporozhskoye reservoir

100%
Zakovenko V., Fedonenko E., Zaychenko E.
International Letters of Natural Sciences
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2016
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tom 56
The study of oil-oxidizing bacteria number and activity has been carried out for the first time in contaminated with oil products and relatively clean areas of Zaporozhskoye reservoir in spring 2014. The research showed high potential oxidative capacity (POC) of water microflora that probably corresponds to the level of water pollution with oil products. During spring season the spatial distribution of oil bacteria as well as dependence on sampling time and water temperature were studied. Analysis of spatial distribution of oil-oxidizing bacteria numbers allowed to perform ranking of the sites with increasing bacteria numbers in direction from the site "Near Kodaki water draw-off" to "Monastyrskiy island". Distribution of oil-oxidizing bacteria observed during the period of study reflects pollution and self-cleaning state of the sites. Using correlation analysis conclusion about connection of oil-oxidizing bacteria with diatoms "bloom" in spring has been made that shows importance of "bloom" for the realization of bacteria role in the reservoir selfcleaning. The results are important for understanding the mechanisms of maintaining Zaporozhskoye reservoir ecosystem stability as well as for forecasting of pollution and self-purification processes and in general for the development and implementation of natural and artificial ecosystems sustainable development.
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Aspects of the reproductive biology of black-striped pipefish Syngnathus abaster Risso, 1827 (Actinopterygii: Syngnathidae) in the Zaporizke Reservoir, Ukraine

84%
Marenkov O.
International Letters of Natural Sciences
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2017
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tom 66
Black-striped pipefish Syngnathus abaster Risso, 1827 (Actinopterygii: Syngnathidae) has successfully spread in freshwater ecosystems of Ponto-Caspian basin. Monitoring studies show a steady increase in the number and biomass of pipefish in waters of Dnipro region. It is highly adaptable and breeds in a fresh water. This fact indicates the physiological plasticity of the reproductive system and ability to adapt to new environmental conditions. In the Zaporizke Reservoir pipefish spawns at a temperature of 18.0–22.0°C in the coastal area of the reservoir. Pipefish with a body length of 8.9 to 12.5 cm had gonads with weight of about 0.13 g, and the number of eggs ranged from 26 to 68. The maximum fertility had female 155 mm long and it reached 69 eggs. Size of eggs reached about 1.2±0.05 mm. The histological analysis of the gonads of pipefish and research of histometric measurements of eggs of fish at various stages of development was first conducted. In the period before pipefish spawning, there were eggs in different stages of maturity in the ovaries: oocyte in the phase of primary follicle «С», oocyte in the phase of vacuolation «D₃», oocyte in the phase of trophoplasmatic growth «Е», beginning phase of mature follicle «F». Research of pipefish reproduction has important theoretical and practical significance for resolving issues with the spread of this species and its adaptation to new conditions.
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The accumulation of heavy metals and cytometric characteristics features of red blood cells in different ages of carp fish from Zaporozhian Reservoir

84%
Fedonenko O., Yesipova N., Sharamok T.
International Letters of Natural Sciences
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2016
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tom 53
The research was held in terms of Zaporozhian Reservoir (Ukraine) from 2014 till 2015 year. It was established that prussian carp (Carassius gibelio Bloch, 1782) and roach (Rutilus rutilus Linnaeus, 1758) underyearlings accumulate essential elements more extensively, especially zinc, comparing to adults ones. The species characteristic of heavy metals accumulation in the carp fish body was observed. The intensity level of erythropoiesis occurrence was higher in young fish of both species of carp fish. The specific features of cytometric characteristics of fish erythrocytes were identified: the relative amount of mature red blood cells prevailed in roach, and the area of mature red blood cells was significantly higher in prussian carp. In addition, in the young roach among immature forms of red blood cells significantly higher percentage of polychromatophil normoblasts was revealed.
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Reproductive biology and quantity evaluation of the Black-striped pipefish Syngnathus abaster (Eichwald, 1831) in the Zaporozhian Reservoir

84%
Fedonenko O., Marenkov O., Stromenko A., Kolesnik N.
International Letters of Natural Sciences
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2016
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tom 52
The article presents the results of biology and ecology studies about the black-striped pipefish Syngnathus abaster (Eichwald, 1831) in the Zaporozhian Reservoir. Quantity and biomass of fish fingerlings and yearlings in different parts of the reservoir was determined. For the first time the reproductive indicators of pipefish in Zaporozhian Reservoir were investigated: the timing of spawning, fish fertility analysis, information on the number of embryos in the brood chamber of males were shown.
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Species composition, seasonal dynamics and distribution of phytoplankton of the Zaporizke Reservoir

67%
Yakovenko V., Melnik S., Fedonenko E.
International Letters of Natural Sciences
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2017
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tom 62
Species composition, seasonal dynamics and distribution of phytoplankton were researched to characterize temporal dynamics and horizontal distribution of phytoplankton and to indicate the ecological status of the sites in the Zaporizke Reservoir. During 2015 - 2016 a seasonal dynamics of species composition and quantitative characteristics of phytoplankton have been studied near Monastyrsky island in upper part of the reservoir both in surface and bottom layers in conjunction with water temperature measurement. At early September 2016 phytoplankton sampling was performed at different sites of the Zaporizke Reservoir including the sites undergone to sewage impact. During phytoplankton seasonal dynamics diatom bloom was reported in March and early April and algae biomass was higher in the bottom layer with a gradual decrease in the direction of the surface layer. From July to October the apparent dominance of blue-green algae took place with a clear concentration in the surface layer. Domination of the species Microcystis aeruginosa determined phytoplankton distribution along the reservoir at the beginning of September. Despite the high resistance to the effects of toxic substances the level of Microcystis aeruginosa (Kützing) Kützing 1846 development decreased at the sites of direct sewage impact. At 100 m below the sewages sites degree of phytoplankton development increased mainly due to increase of blue-green algae abundance. Indexes of phytoplankton showed the best ecological state at the site «near Kodaki water draw-off» and the worst ecological state at the sites of direct sewage impact. The results obtained are important to indicate ecological state of the sites in the Zaporizke Reservoir.
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Indexes of lipid metabolism in fish from the Zaporizke Reservoir

67%
Tamila A.
International Letters of Natural Sciences
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2017
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tom 64
The total lipid contents and iodine value of fats had been determined in fish from two sections of the Zaporizke Reservoir (Ukraine) with different contamination levels. Research was conducted using the muscle and liver tissue samples from pike-perch (Sander lucioperca), european perch (Perca fluviatis), prussian carp (Carassius gibelio), roach (Rutilus rutilus) and rudd (Scardinius erythrophthalmus). Obtained data showed that at the contaminated zone, the total lipid contents were significantly (p ≤ 0.05) reduced in muscle tissue of pike-perch and european perch in comparison with the samples from “conventionally clean” lower section of the reservoir. Increased iodine value of fats in muscle tissue and liver tissue were detected in the predatory fish and both fish groups respectively. The research results could be used for estimation of the adaptation processes in freshwater fish as well as for indication of environmental contamination level in the natural and artificial reservoirs.
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Parameters of the histological adaptation of marmorkrebs Procambarus virginalis (Lyko, 2017) (Decapoda, Cambaridae) to manganese, nickel and lead ions pollution

67%
Naboka A., Marenkov O., Kovalchuk J., Shapovalenko Z., Nesterenko O., Dzhobolda B.
International Letters of Natural Sciences
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2018
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tom 70
Manganese, lead and nickel are heavy metals, which are the primary fresh water toxic contaminants being in the most dangerous class of chemicals. Heavy metals cause functional disorders in the tissues and organs of hydrobionts, affecting their linear and weight indices, reproductive system, digestive and extraction organs. In our experiment on marbled crayfish Procambarus virginalis (Lyko, 2017) we studied the long-term effects of various concentrations of heavy metal ions on the physiological state and histostructure of tissues and organs. According to the results of research, it was found that among the studied heavy metals nickel ions influenced the weight indexes and mortality of crustaceans the most negatively. The results of morphometric studies on marbled crayfish indicate no significant differences between the control group and experimental one, but heavy metals influenced the form of the hepatopancerase lobes and the size of the lumen of the gland. Research on adipocytes of the connective tissue showed a significant difference between the size of cells under the influence of heavy metals. Dimensions of adipocytes fluctuated over a wide range from 144 μm² to 537 μm². In control group the adipocyte area was 406.96 μm². Experimental studies of hemolymph showed that, under the influence of lead ions, a significant 1.4 times increase was observed in the area of hemolymph cells; when manganese and nickel were added, moderate decrease was observed in cells. It was found that under the influence of nickel, the area of round hyalinocytes has reduced by 1.7 times.
8
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Reproductive features of roach, bream and common carp of Zaporozhian (Dnipro) Reservoir in contemporary environmental conditions

67%
Marenkov O.
International Letters of Natural Sciences
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2016
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tom 57
Over the past 50 years, the complete histological study of carp fish gonads was first carried out at Zaporozhian Reservoir. In conditions of environmental transformation of the reservoir the regularities of oogenesis and gonadogenesis, passing sexual cycles were found and the ecology of spawning carp fish was investigated. The adaptive potential of the carp fish reproductive systems, which is expressed through the asynchrony of reproductive products development as well as the functional peculiarities of the fish spawning process, was brought to light. Both environmental assessment and faunal analysis of biodiversity and distribution of young fish of Zaporozhian Reservoir were carried out. The growth and development of the fish larvae dwelling within the industrial agglomerations of Dnipropetrovsk city are found to be under anthropogenic influence. The efficiency of the use of artificial spawning nests for the carp fish spawning was studied, and practical recommendations for their installation and operation in the waters of the reservoir were elaborated.
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The technology for reduction of fishes suffocation during winter period on example of Dnieper reservoirs

67%
Timchenko V. M., Timchenko O. V.
International Journal of Ecohydrology and Hydrobiology
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2001
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tom 01
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nr 3
The two ways of modification the oxygen conditions of dam reservoirs in order to protect fish from suffocation at freezing periods were presented: 1) the ice-hole size enlargement, and 2) short-term rises of a water level to raise oxygen concentration in the waters in fishes wintering sites. Both the methods are based on the modifications of the water flow through hydroelectric power stations as the only management tool. The mathematical formulae for calculating water flows and its effects are presented, as well as examples of calculation for January and February for Kremenchuk Reservoir (Dnieper River).
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