scholarly journals HYDROBIOLOGICAL STUDIES OF PLANKTON COMMUNITIES OF MAKHACHKALA SEAPORT

2019 ◽  
pp. 12-18
Author(s):  
Magomed Magomedovich OSMANOV ◽  
Frangiz Shamilievna AMAEVA ◽  
Ayshat Abdulmajidovna ABDURAKHMANOVA
Keyword(s):  
Aquatic Organisms ◽  
Water Area ◽  
Acartia Tonsa ◽  
Anthropogenic Influence ◽  
The Caspian Sea ◽  
Spring Period ◽  
Brackish Water Species ◽  
Water Species ◽  
Plankton Communities ◽  
Planktonic Communities

The article presents data from spring hydrobiological studies in the Makhachkala l Seaport during the period of dredging. It is noted that plankton of the studied water area of the Caspian Sea is a typical community of the spring period, formed mainly by marine and brackish-water species of phytoplankton and zooplankton. Diatoms mainly dominate in phytoplankton, and Copepods in zooplankton, where the main dominant is the Azov-Black sea invader Acartia tonsa Dana,1843. The analysis of planktonic communities indicates a rather developed quantitative and qualitative community of aquatic organisms with a characteristic abundance of species inhabiting it in the spring, despite a significant anthropogenic influence. It is established that the ongoing dredging operations do not have a tangible effect on the productivity of planktonic organisms.

scholarly journals MODERN CONDITION AND PECULIARITIES OF DISTRIBUTION OF THE ZOOPLANKTON OF THE COASTAL AQUATORIA OF THE MANAS-OZEN OF THE CASPIAN SEA

2019 ◽  
pp. 6-11
Author(s):  
Magomed Magomedovich OSMANOV ◽  
Frangiz Shamilievna AMAEVA ◽  
Magomed Abdulaevich GURUEV ◽  
Murad Mukhtarovich ALIGADZHIEV ◽  
Ayshat Abdulmajidovna ABDURAKHMANOVA
Keyword(s):  
Caspian Sea ◽  
Biological Diversity ◽  
Water Area ◽  
Acartia Tonsa ◽  
Mnemiopsis Leidyi ◽  
Biological Productivity ◽  
The Caspian Sea ◽  
Positive Role ◽  
Modern Condition

The article presents the research data on the biological diversity and dynamics of the zooplankton complexes structure of the Manas-ozen of the Daghestan coastal water area of the Caspian Sea in modern conditions. It is noted that the formation of the zooplankton complex of the studied area is seasonal. The positive role of Acartia tonsa Dana in maintaining the biological productivity of the studied area under the conditions of Mnemiopsis leidyi A. Agassiz introduction is also noticed.

scholarly journals Assessing Diazinon Pollution in the Three Major Rivers Flowing into the Caspian Sea (Iran)

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 335
Author(s):  
Reza Dahmardeh Behrooz ◽  
Abbas Esmaili-sari ◽  
Magdalena Urbaniak ◽  
Paromita Chakraborty
Keyword(s):  
High Risk ◽  
Organophosphorus Pesticides ◽  
Aquatic Organisms ◽  
The United States ◽  
The Caspian Sea ◽  
Worst Case ◽  
Pollution Levels ◽  
Haraz River ◽  
Significant Difference ◽  
Medium Risk

The aim of this study was to investigate the seasonal and spatial variations in the concentrations of a widely used organophosphorous pesticide (OPP), diazinon, and the associated risk posed by this OPP in the surface water from the three largest rivers located in the northern province of Iran: the Haraz, the Talar and the Babolrood rivers. These rivers are located in the agriculture province of Mazandaran, and are exposed to high doses of organophosphorus pesticides, especially diazinon. The concentration of diazinon was determined using gas chromatography, while the potential risk posed by diazinon was elucidated using a Risk Quotient (RQ) calculated for general (RQm) and worst-case (RQex) scenarios. The obtained results demonstrated that the average diazinon concentrations ranged from 41 ± 76 ng/L in the Talar River and 57 ± 116 ng/L in the Haraz River, to 76.5 ± 145 ng/L in the Babolrood River, with a significant difference noted between summer and autumn seasons for all three rivers. For some stations, the concentration of diazinon is higher than the standard guidelines of Australian/New Zealand Guidelines for Fresh and Marine Water Quality (FMWQ) and the United States Criteria Maximum Concentration (CMC). The calculated RQs indicated a medium risk of diazinon, RQm = 0.73 and RQex = 2.27, in the Talar River; RQm = 1.02 and RQex = 2.49 in the Haraz River; and RQm = 1.35 and RQex = 4.54 in the Babolrood River. The overall exposure of diazinon was defined to have a high risk (RQm and RQex > 1); however, the summer sampling revealed a high risk (RQm and RQex > 1), while the autumn had a medium risk (RQm and RQex < 1). The obtained results revealed not only elevated concentrations of diazinon in the studied rivers but most importantly the high risk posed by this OPP for the aquatic organisms and the wellbeing of the whole river ecosystem. The current study showed that development and implementation of appropriate standards and regulations toward diazinon in countries such as Iran are required to reduce the pollution levels and risks related to elevated concentrations of the studied pesticide.

scholarly journals Cadmium content in aquatic organisms of the Caspian Sea

2022 ◽  
Vol 16 (4) ◽  
pp. 37-46
Author(s):  
T. S. Ershova ◽  
V. F. Zaitsev ◽  
V. A. Chaplygin ◽  
A. S. Khursanov
Keyword(s):  
Caspian Sea ◽  
Aquatic Organisms ◽  
Cadmium Content ◽  
The Caspian Sea

scholarly journals MICROALGAE FROM THE COASTAL WATERS OF TYULENY ISLAND IN THE CASPIAN SEA

2019 ◽  
Vol 14 (2) ◽  
pp. 120-131
Author(s):  
R. M. Barkhalov ◽  
A. A. Abdurakhmanova ◽  
F. Sh. Amaeva
Keyword(s):  
Coastal Waters ◽  
Caspian Sea ◽  
Biomass Concentration ◽  
Water Area ◽  
Trophic Chain ◽  
The Caspian Sea ◽  
Standard Procedures ◽  
Water Surface Layer ◽  
Rich Flora ◽  
Positive Effect

Aim. In this work, we set out to study the composition of a phytoplankton community in an important fishery area, the coastal water area of Tyuleny Island in the Caspian Sea.Methods. We present the results of seasonal observations (2016) on the state of phytoplankton in the coastal waters of Tyuleny Island in the Caspian Sea. In total, 120 phytoplankton samples were collected at four stations from the water surface layer (May–October) using the Nansen bottle and subsequent fixation by Lugolʹs solution. Sedimentation and concentration were carried out using standard procedures. The samples were processed in the Nageotte chamber with a volume of 0.1 ml under a light microscope.Results. According to the research results (2016), 103 species and varieties of microalgae were found in the phytoplankton samples collected from the water area of Tyuleny Island. The microalgae were represented by four divisions: Bacillariophyta – 49 species, Cyano‐ phyta – 24 species, Chlorophyta – 23 species and Pyrrophyta – 7 species. The greatest species diversity of phytoplankton in the studied water area was noted during the autumn period (61 spe‐ cies). In general, phytoplankton was found to be distributed homogeneously throughout the coastal area of the island, with the biomass concentration not reaching 1 g/m3.Conclusion. In 2016, favorable hydrological and hydrochemical conditions for the development of microalgae were observed. The desalinated water around Tyuleny Island, which is well warmed in the summer and does not freeze in the winter, contributed to the development of rich flora. Although bi‐ omass values were not high due to the prevalence of small‐celled microalgae in phytoplankton, in general, it should have a positive effect on the development of subsequent links in a trophic chain, as well as promote an increase in the productivity of waters of the Northern Caspian Sea. 

Mastogloia jahniae sp. nov., a new diatom (Bacillariophyceae) from the Baltic Sea coast of Sweden

Phytotaxa ◽  
2021 ◽  
Vol 484 (1) ◽  
pp. 121-128
Author(s):  
ADIL Y. AL-HANDAL ◽  
ANGELA WULFF ◽  
CHIARA PENNESI
Keyword(s):  
New Species ◽  
Baltic Sea ◽  
East Coast ◽  
Central Area ◽  
The Baltic Sea ◽  
The Baltic ◽  
Brackish Water Species ◽  
Water Species ◽  
Sea Coast ◽  
Scanning Electron

Described is here Mastogloia jahniae sp. nov. a species new to science from Skatan on the Baltic Sea, east coast of Sweden. Description of this new species is based on light and scanning electron microscopy. The new species is classified in the Mastogloia section Ellipticae and is characterized by having radiating short and long striae around the central area, sinuous raphe branches and partecta displaced toward the middle of the valve by a siliceous flange. M. jahniae sp. nov. in terms of size is rather small whereas in terms of ecology appears an epipelic brackish water species. The new species was rather rare in all samples collected from Skatan and has not been found in the other adjacent regions sampled. A comparison with similar established Mastogloia species is provided.

New Stage in the Geopolitical Struggle around the Caspian Sea after 1991

2021 ◽  
Vol 13 (1) ◽  
pp. 21-36
Author(s):  
Stanislav Aleksandrovich Pritchin
Keyword(s):  
Caspian Sea ◽  
Legal Status ◽  
Oil And Gas ◽  
Political Influence ◽  
Water Area ◽  
The Caspian Sea ◽  
Regional Powers ◽  
Complete Work ◽  
Strategic Goals ◽  
The Military

For almost three centuries, starting with the campaign of Peter the Great in 1721-1722, Russia has traditionally played a key role in the Caspian Sea. The situation changed dramatically with the collapse of the USSR in 1991 and the emergence of three new regional players-Azerbaijan, Kazakhstan and Turkmenistan. For Russia, this meant a significant reduction in influence in the region and the loss of control over most of the water area and the sea and its resources. In the historiography devoted to the region, the emphasis is placed on assessing the new round of geopolitical struggle, the position and interests of Western and regional powers. The author of this article provides a critical analysis of changes in Russian policy towards the Caspian Sea over the past 30 years and assesses the effectiveness of these changes. The difficult transition from the role of a dominant player in a region closed to external competitors to an open geopolitical confrontation over resources, their transportation routes, and political influence at the first stage was not in favor of Russia. Russia could not defend the principle of a condominium for joint development of hydrocarbon resources of the sea. With the active assistance of Western competitors, Russia lost its status as a monopoly transit country for oil and gas from the region. At the same time, thanks to diplomatic efforts and increased political dialogue with its neighbors in the region, Russia managed to resolve all territorial issues at sea by 2003, maintain the closed status of the sea for the military forces of third countries, and by 2018 complete work on the Convention on the international legal status of the sea, which established the principles of cooperation in the region that are important for the Russian Federation. Thus, official Moscow managed to achieve the strategic goals adapted after the collapse of the USSR by using the traditional strengths of its foreign policy and consolidate its status as the most influential player in the region.

HYDROGEOLOGICAL CHARACTERISTICS OF RESERVOIR WATERS OF THE CASPIAN SEA DEPOSITS

2021 ◽  
Vol 82 (3) ◽  
pp. 33-48
Author(s):  
NABIEVA VICTORIA V. ◽  
◽  
SEREBRYAKOV ANDREY O. ◽  
SEREBRYAKOV OLEG I. ◽  
◽  
...  
Keyword(s):  
Oil Recovery ◽  
Caspian Sea ◽  
Oil And Gas ◽  
Chemical Properties ◽  
Water Area ◽  
Water Soluble ◽  
Salt Composition ◽  
The Caspian Sea ◽  
Recovery Coefficient ◽  
Hydrogeological Characteristics

Hydrogeological conditions of reservoir waters of oil and gas fields in the northern water area of the Caspian Sea characterize the geological features of the structure of the Northern Caspian shelf, as well as the thermodynamic parameters of the exploitation of productive deposits, production and transportation of oil and gas. Reservoir waters contain water-soluble gases. According to the size of mineralization, the ratio of the main components of the salt composition, as well as the presence of iodine and bromine, reservoir waters can be attributed to a relatively "young" genetic age, subject to secondary geochemical processes of changing the salt composition in interaction with "secondary" migrated hydrocarbons. The physical and chemical properties of reservoir waters are determined by PVT analysis technologies. Hydrogeological and geochemical studies of compatibility with reservoir waters of marine waters injected to maintain reservoir pressures (PPD) during the development of offshore fields in order to increase the oil recovery coefficient (KIN) indicate the absence of colmating secondary sedimentation in mixtures of natural and man-made waters.

Macrostomum shenda and M. spiriger, two new brackish-water species of Macrostomum (Platyhelminthes: Macrostomorpha) from China

Zootaxa ◽  
2019 ◽  
Vol 4603 (1) ◽  
pp. 105
Author(s):  
FAN XIN ◽  
SI-YU ZHANG ◽  
YONG-SHI SHI ◽  
LEI WANG ◽  
YU ZHANG ◽  
...  
Keyword(s):  
Brackish Water ◽  
Phylogenetic Analyses ◽  
28S Rdna ◽  
Body Region ◽  
Rdna Sequences ◽  
Molecular Phylogenetic ◽  
28S Rdna Sequences ◽  
Pore Opening ◽  
Brackish Water Species ◽  
Water Species

In this study, two new brackish-water species of Macrostomum (M. shenda n. sp. and M. spiriger n. sp.) collected from Shenzhen, China, were described based on morphological, histological, and molecular phylogenetic analyses. Macrostomum shenda n. sp. differs from its congeners in the oblique and non-thickening distal opening of its narrow funnel-shaped stylet. In addition, its sperm have neither bristles nor brush, and are surrounded by an undulating membrane in the mid-body region. In M. spiriger n. sp., the stylet is spirally twisted. Its reproductive apparatus has a seminal bursal pore opening exteriorly. Results of the 18S and 28S rDNA phylogenetic analyses also support the establishments of these two new species. Moreover, the 18S and 28S rDNA sequences of some species within Macrostomum in previous studies have been revised to avoid ambiguity, while Macrostomum dongyuanensis Wang & Sun, 2015 was re-identified as a new record of M. quiritium Kolasa, 1973 from China.

Chaetoceros pauciramosus sp. nov. (Bacillariophyceae), a Widely Distributed Brackish Water Species in the C. lorenzianus Complex

Protist ◽  
2018 ◽  
Vol 169 (5) ◽  
pp. 615-631 ◽  
Author(s):  
Zuo Yi Chen ◽  
Nina Lundholm ◽  
Øjvind Moestrup ◽  
Janina Kownacka ◽  
Yang Li
Keyword(s):  
Brackish Water ◽  
Brackish Water Species ◽  
Water Species

Observations by Means of Cine Photography on the Behaviour of the Haptonema in Plankton Flagellates of the Class Haptophyceae

1971 ◽  
Vol 51 (1) ◽  
pp. 207-217 ◽  
Author(s):  
B. S. C. Leadbeater
Keyword(s):  
Fine Structure ◽  
Light Microscopy ◽  
Brackish Water ◽  
Type Species ◽  
Smooth Surface ◽  
Marine Species ◽  
Phaeocystis Globosa ◽  
The Third ◽  
Brackish Water Species ◽  
Water Species

INTRODUCTIONInitially the haptonema was recorded as a ‘little additional flagellum’ by Scherffel (1899) when he described Phaeocystis globosa. Similarly, the haptonema was referred to as the ‘third flagellum’ on the apparently tri-flagellate, brackish-water Prymnesium saltans Massart (Massart, 1920). Two further brackish water species of Prymnesium were described by Carter (1937) and all were characterized by a very short immobile ‘third appendage’. Lackey (1939) found a freshwater organism similar to Prymnesium but it possessed a ‘third flagellum’ several times the length of the true flagella. He re-corded that the third appendage was held out rigidly when the cell was at rest but during rapid swimming he was unable to see it and thought that this was due to an extremely rapid beat. He named his new organism Chrysochromulina parva and C. parva Lackey is now the type species of a considerable genus.Parke, Manton & Clarke (1955,1956,1958,1959) made a study of the light microscopy and fine structure of numerous marine species of Chrysochromulina. Their results showed that the ‘third flagellum’ differed in appearance and structure from that of a true flagellum and hence they decided to call this organelle a haptonema owing to its thread-like form and its ability to adhere to a smooth surface (Parke, Manton & Clarke, 1955). Their observations revealed that the haptonema could attach to a surface by an ‘adhesive tip’ and that the majority of species could coil their haptonemata into a helix and extend it again. In some species, e.g. C. strobilus (Parke, Manton & Clarke, 1959), the haptonema was usually tightly coiled whilst the cell was swimming.

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