scholarly journals Phytoplankton as an indicator of the current ecological status of the Ob River

2021 ◽  
Vol 7 ◽  
pp. 573-591
Author(s):  
Natalya N. Barsukova ◽  
Olga P. Bazhenova ◽  
Larisa G. Kolesnichenko

The species composition, taxonomic structure, and the dominant complex of algae, and the distribution of phytoplankton abundance in the studied watercourse were identified based on data obtained for phytoplankton from the Ob River (from Tomsk to Salekhard) in summer 2019. Green algae (division Chlorophyta) make up the basis of the phytoplankton abundance in the river. The dominant complex is represented mainly by centric diatoms (genera Aulaсoseira, Cyclotella, Stephanodiscus) and non-heterocyst forms of cyanoprokaryotes (genus Aphanocapsa). The numbers and biomass of phytoplankton gradually decrease downstream of the Ob River; below the confluence of the Irtysh River, the edge effect occurs: increase in the diversity and density of organisms at the boundaries of ecosystems. Compared to the previous studies, the proportion of green and euglena algae, and cyanoprokaryotes in the taxonomic spectrum of phytoplankton increased, the composition of the dominant complex enriched, including due to non-heterocyst forms of cyanoprokaryotes, and the trophic status of the river increased to the category of eutrophic waters.

2021 ◽  
Vol 22 (3) ◽  
Author(s):  
Irina V. Mashkova ◽  
Anastasiya Kostryukova ◽  
Elena Shchelkanova ◽  
Viktor Trofimenko

Abstract. Mashkova IV, Kostryukova AM, Shchelkanova EE, Trofimenko VV. 2021. Short Communication: Zooplankton as indicator of trophic status of lakes in Ilmen State Reserve, Russia. Biodiversitas 22: 1448-1455. Zooplankton is a potentially powerful tool for assessing the trophic state of aquatic ecosystems. The current paper studied taxonomic composition and biomass of zooplankton communities in ten lakes within Ilmen State Reserve, Chelyabinsk region, Russia and identified the influence of trophic status on its formation. Integrated samples were taken from epilimnion in the summer of 2016-2019. Several criteria were used to determine trophic status: the taxonomic structure and biomass of zooplankton; some hydroecological indicators some hydroecological indicators and the Carlson index. The trophic status of the studied lakes, determined based on the zooplankton biomass, revealed that most of the lakes were in the status of mesotrophic. The number of zooplankton species in the lakes was 44 with Pleuroxus laevis, Bosmina longirostris, Simocephalus vetulus were the most numerous species in mesotrophic lakes; while Chaetonotus ploenensis, Keratella quadrata frenzeli, Leptodora kindti are rare. Zooplankton communities of Bolshoye Miassovo and Maloye Miassovo Lakes were characterized by high species diversity and considered as one of the most significant among the foothill lakes of the eastern slope of South Ural. The study reveals that hydroecological assessment of the ecological status is not exactly precise, as values are not stable and can change not only under the anthropogenic influence but also due to many natural abiotic environmental factors. The research shows that species composition and biomass of zooplankton communities could provide a more accurate assessment of the trophic status of water-bodies.


Author(s):  

Issues concerning the Irtysh River and the Ob River interaction and the backwater processes during the Irtysh River mouth areas depressions formation (their origin is still disputable) have been discussed. The backwaters hydro/climatic and geo/morphologic factors have been analyzed; a hydrodynamic hypothesis to explain river moth areas backwaters has been suggested.


2019 ◽  
Vol 9 (4) ◽  
pp. 481-501
Author(s):  
Aleksandra Maiurova ◽  
Marina Kustikova

In this paper the dynamics of invasion extensiveness of freshwater Bithyniidae snails by trematodes Opisthorchis felineus (cat fluke) in the waters of Khanty-Mansi Autonomous Area was determined. The study was conducted for the Ob river (Surgut) and the Irtysh river (Khanty-Mansiysk) for 7 years. As a result of the study, it was determined that the population density of snails and the extensiveness of their invasion by O. felineus trematodes are higher in the Irtysh River, which is associated with the hydrological regime of the river. Indicators of invasion extensiveness are higher for Bithynia tentaculata snails than Bithynia troscheli.


Purpose. Determination of the main factors of anthropogenic impact of the urban system of the city of Lutsk on the river basin of the river Sapalaivka and assessment of the ecological condition of the river on the basis of MIR "Macrophytic index of rivers". Methods. Comparative-geographical, generalization, systematization, statistical, comparative-analytical, descriptive, cartographic. Results. In the Sapalaivka River, 21 indicator species of macrophytes were found in the surveyed test areas, among which - 8 plants belong to dicotyledons, and 13 plants belong to monocotyledons, using which the MIR values ​​were calculated. Depletion of macrophyte species composition from 15-16 in test plots 1 and 2 to 2 species in test plot 3 indicates deterioration of the ecological condition of the river and the emergence of unfavorable conditions for macrophyte habitats. On the territory of the city, the section of the Sapalaivka riverbed, from the beginning of Potapova Street to the mouth, is mostly canalized, the species composition of macrophytes is depleted here and there is a specific smell of sewage. The part of the river that flows in the city (before Potapova Street), which was renaturalized in 2012-2016, has a richer species composition of macrophytes. Outside the city, the Sarpalaivka river basin is in good condition, as evidenced by the species composition of flora and fauna, as well as the intensive development of higher aquatic vegetation. Conclusion. As a result of the calculated ecological index of macrophytes MIR it is established that the water quality in the river Sapalaivka on the test site № 1, belongs to the II class, category - good and by trophic status is mesotrophic; on the test site № 2, belongs to the III class, category - satisfactory and eutrophic in trophic status; on the test site № 3, belongs to class IV, category - poor and trophic status is polytrophic. It is advisable to carry out further environmental measures, especially in the lower reaches of the river, in order to eliminate sources of water pollution, and to monitor the ecological status of the reservoir in order to restore the species composition of macrophytes and the ability to self-clean.


2019 ◽  
pp. 61-72
Author(s):  
T. V. Belich ◽  
S. Ye. Sadogurskiy ◽  
S. A. Sadogurskaya

The results of nomenclature-taxonomic revision of the flora marine macrophytes of the Kazantip Nature Reserve (KNR) are presented. Currently, with the new data the species composition includes 73 species and intraspecific taxon (IST) of macroalgae and sea grasses. Taxonomic structure of flora of the macrophytes of the KNR includes 4 phylums, 7 classes, 19 orders, 28 families, (F), 37 genera. Chlorophyta - 33 species, Ochrophyta - 11, Rhodophyta - 25, Tracheophyta - 4. In the flora prevail mesosaprobic (44%), annuae (58%), brackish-sea (51%), warm-water (40%) species. The category of rare fraction includes 14 species.


Zootaxa ◽  
2017 ◽  
Vol 4247 (2) ◽  
pp. 141 ◽  
Author(s):  
OLEG E. KOSTERIN ◽  
NAZYMGUL AKIMBEKOVA ◽  
VLADIMIR V. DUBATOLOV ◽  
IGNAC SIVEC

Taeniopteryx araneoides Klápalek, 1902, a stonefly species with brachypterous males, known historically from the Danube, Elbe, and Dniester rivers, but considered to be extinct at least in Europe for more than a century. This species has also been doubtfully reported from Krasnoyarsk, Central Siberia. However, we report this species to be still thriving in the Irtysh River at the cities of Omsk (West Siberia, Russia) and Pavlodar (North Kazakhstan). The occurrence of this species reported least fifty years ago from the Yenisey River at Krasnoyarsk, Russia is considered possible. Unlike the widespread Palaearctic T. nebulosa (Linnaeus, 1758) that occurs in a broad range of stream types, T. araneoides is a potomon species, apparently confined to large rivers. In this habitat, it appears vulnerable to anthropogenic impacts and may be unable to compete with T. nebulosa. The construction of dams and reservoirs has apparently extirpated T. araneoides from most of its former geographical range. 


2015 ◽  
Vol 49 (1) ◽  
pp. 75-86 ◽  
Author(s):  
M. V. Orlova ◽  
O. L. Orlov

Abstract The article presents the most complete data on the distribution of ectoparasites in the boreal Palaearctics (gamasid mites of the genera Spinturnix, Macronyssus, and Steatonyssus, bat flies of the family Nycteribiidae, fleas of the family Ischnopsyllidae) and its preferences for the hosts. On the basis of these data as well as the data for the resettlement of bats in Eurasia 30 species of boreal bat ectoparasites combined into three faunal complexes (Transpalaearctic, European-Ural and Siberian-Far East) and two groups (European-Ural species, penetrating to the east and Siberian-Far East, penetrating to the west). The boundary between the European-Ural and Siberian-Far East faunal complexes is situated presumably along the Irtysh River. The resulting zoning provides a new look at the parasitocenosis of ectoparasites in the taiga zone of the Palaearctics.


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