scholarly journals TAXONOMIC COMPOSITION OF THE PHYTOPLANKTON IN THE MIDLE CASPIAN SEA

2019 ◽  
pp. 11-17
Author(s):  
Magomedzagid Kaisovich GUSEYNOV ◽  
Aysha Sharapatinovna GASANOVA ◽  
Kais Magomedovich GUSEYNOV ◽  
Marina Vladimirovna KHLOPKOVA
Keyword(s):  
Caspian Sea ◽  
Phytoplankton Community ◽  
Water Area ◽  
Taxonomic Composition ◽  
Small Cell ◽  
Dynamic State ◽  
Shallow Waters ◽  
The Caspian Sea ◽  
Russian Water ◽  
Size Groups

A high variyety of vegetation and a predominance of small cell forms are typical of the current structure of the phytoplankton of the seacoastal shallow waters of the Russian coastline of the Caspian Sea. The replacement of the dominating complex and the size groups of the phytoplankton has occurred. The phytoplankton community is represented by six categories: Cyanophyta, Bacillariaphyta, Dinophita, Euglenophyta, Chlorophyta, and the small flagellates. The basis of the taxonomic variety consists of the Diatoms algae. The composition of species of the phytoplankton of the sea coastal shallow waters of the Russian water area of the Middle Caspian is in a dynamic state and depends on the direction of the change of water regime.

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. 

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.

scholarly journals ORGANIZATION OF ENVIRONMENTAL MONITORING IN THE CASPIAN SEA

ScienceRise ◽  
2020 ◽  
Vol 2 ◽  
pp. 3-9
Author(s):  
Nazila Ali Ragimova ◽  
Vugar Hajimahmud Abdullayev ◽  
Vasila Soltanaga Abbasova
Keyword(s):  
Environmental Monitoring ◽  
Monitoring System ◽  
Caspian Sea ◽  
Ecological Monitoring ◽  
Water Area ◽  
Environmental Data ◽  
The Caspian Sea ◽  
Environmental Situation ◽  
Environmental Monitoring System ◽  
Technological Product

The object of research is ecological monitoring of the Caspian Sea. This article addressed the objectives and components of environmental monitoring. It also describes the objectives for the establishment of a Unified State Environmental Monitoring System. Special attention is paid to the structure of the environmental network monitoring system, which consists of three levels: low, medium and high. One of the main problems is the establishment of the Unified State Environmental Monitoring System of the Caspian Sea. This article considered the main functions and objectives of the Unified State Environmental Monitoring System. Here are also discussed the computing center of the environmental monitoring system and its functions and components. The research used three main components for environmental data processing: database management systems, geographic information system and integrated software packages. Examples of a computer system of environmental monitoring include: ArcGIS, MapInfo, ArcView and OCEAN. The main scientific results of this research are the main functions, objectives and components of environmental monitoring of the Caspian Sea to reduce pollution levels. The obtained results can be used to optimize the characteristics of environmental information systems, which are used to organize environmental monitoring. Innovative technological product of this research is the development of an algorithm for the organization of environmental monitoring of the Caspian Sea. It will allow ecologists to monitor the environmental situation of the Caspian Sea and further improve it. The obtained innovative technological product will be useful for carrying out environmental monitoring of the most contaminated section of the water basin, and more precisely for monitoring the scale of pollution and further improving the environmental situation of the water area.

State of populations and fishing of semi-anadromous fish in the North-Eastern Caspian sea

2021 ◽  
pp. 22 (87)-30 (94)
Author(s):  
Askarbay Kadralievich Kamelov
Keyword(s):  
Caspian Sea ◽  
Water Area ◽  
The State ◽  
Anthropogenic Factors ◽  
Anadromous Fish ◽  
The Caspian Sea ◽  
The North ◽  
Natural Reproduction ◽  
Pike Perch ◽  
North Eastern

Semi-anadromous fish (roach, bream, pike-perch, asp) are the main objects of fishing in the coastal zone of the North-Eastern part of the Caspian Sea. The state of the populations of these fish changes significantly under the influence of natural and, especially, anthropogenic factors, which have increased in recent years. The aim of this work was to study the current state of populations of semi-anadromous fish in the NorthEastern Caspian Sea. Based on the materials of three years of research (2016, 2018, 2020), with the involvement of literary sources, long-term changes in the size-weight and, age indicators, nutritional status of fish and the sex ratio in populations are considered. It has been established that the state of the semi-anadromous fish populations in the North-Eastern Caspian remains tense at the present time. All populations are characterized by general negative patterns of state change. There are tendencies of decrease in size, weight and age indicators, the number of populations and fish catches are decreasing. These changes were least of all manifested in bream (whose state is relatively stable) and were most pronounced in pike perch. The depressive state of the populations is explained by a decrease in the scale of natural reproduction in recent years, due to a decrease in the water content of the Ural River and the number of spawners allowed to spawn on the river. Marine fisheries in the North-Eastern Caspian are concentrated in shallow waters, which increases the fishing load on semi-anadromous fish and prevents their passage to spawning. It is necessary to reduce the pressure of fishing by reducing the number of nets used in the shallow water area of the North-Eastern Caspian and strict observance of the rule of the forbidden pre-estuary space of the river Ural. English version of the article on pp. 87-94 is available at URL: https://panor.ru/articles/state-of-populations-and-fishing-of-semi-anadromous-fish-in-the-north-eastern-caspian-sea/64076.html

scholarly journals TSUNAMI HAZARD ASSESSMENT IN THE CASPIAN SEA

2019 ◽  
Vol 47 (5) ◽  
pp. 74-88
Author(s):  
E. A. Kulikov ◽  
A. Yu. Medvedeva ◽  
I. V. Fine
Keyword(s):  
Hazard Assessment ◽  
Caspian Sea ◽  
Water Area ◽  
Tsunami Hazard ◽  
Estimation Of Parameters ◽  
The Caspian Sea ◽  
Tsunami Waves ◽  
The North ◽  
Tsunami Hazard Assessment ◽  
Run Up

The article describes the tsunami hazard assessment for the coast of the Caspian Sea, in particular for the Absheron Peninsula. Due to the high socio-economic load on the coast of this region by electric power and oil production industries requirements, it is necessary to take into account risks even for such extremely rare natural phenomena like tsunamis. An earthquake with M = 8 ± 0.2 can occur throughout the Caspian Sea region, including land, once every 216 years, while for the water area the frequency of occurrence of such an event is 1620 years. The article presents the results of a tsunami hazard assessment based on a deterministic approach for the Absheron Peninsula. This approach of the tsunami hazard assessing of an arbitrary part of the coast consists of selecting of the strongest observed (or hypothetical) tsunami event from a neighborhood and from a distant zone, of the subsequent estimation of parameters for model sources and, finally, of the numerical modeling of tsunami generation and propagation from these sources. It was obtained that with the propagation of tsunami waves from the north to the coast of the Absheron Peninsula, its height can reach 3‒4 m for some parts of the coast with run-up 500‒1500 m.

scholarly journals FEATURES OF BEHAVIOR OF ORDINARY SPRAT (BY RESULTS OF HYDROACOUSTIC RESEARCHES)

2018 ◽  
pp. 65-73
Author(s):  
Igor Borisovich Balchenkov ◽  
Tatiana Vasilievna Pomogaeva
Keyword(s):  
Caspian Sea ◽  
Water Area ◽  
Early Spring ◽  
Middle Part ◽  
Summer Period ◽  
The Caspian Sea ◽  
Research Ship ◽  
Study Results ◽  
Seasonal Aspect ◽  
Made In

Caspian sprats are reserve target species. The study of species identification of Caspian sprats was carried out on board a research ship “Researcher of the Caspian Sea” using EK-60 hydroacoustic complex having stationary antennas with a split beam of 38 and 120 kHz. The behavior and distribution of ordinary sprats in the western part of the Caspian Sea (Middle part of the Caspian Sea off the coast of Dagestan) was investigated. Echo recordings of hydroacoustic surveys made in 2011-2017 covering the water area with depths from 20 to 300 meters were considered. A database with hydroacoustic research files was created, containing the parameters of the surveys and the graphic display of the echograms. Taking into account the negative reaction of ordinary sprat to light, both day and night recordings were considered. Characteristic echoes of ordinary sprat are described in the seasonal aspect. These studies, describing the nature of the behavior of ordinary sprats, are important for the organization of fishing in the western part of the Caspian Sea. It has been stated that density of sprat shoals during spring-summer period is not high, fishing by bottom trawl is efficient only at the end of August. The most promising sprat accumulations can be found in early spring (March) and in October and November, when sprat is caught in the industrial scale. The study results describing special behavior of ordinary sprats can be used in organizing sprat fishing in the Western part of the Caspian Sea.

scholarly journals ECOLOGICAL RISK OF A SAND QUARRY EXCAVATION IN THE RIVERBED

2018 ◽  
pp. 7-16
Author(s):  
Andrey Stepanovich Aldokhin ◽  
Andrey Aleksandrovich Chemagin
Keyword(s):  
Water Quality Assessment ◽  
Biological Indicators ◽  
Fish Population ◽  
Water Area ◽  
Taxonomic Composition ◽  
Fish Density ◽  
Negative Consequences ◽  
Sturgeon Species ◽  
Size Groups ◽  
Taxonomic Groups

The article describes the potential negative consequences of hydraulicking a sand quarry in the Irtysh channel: vibration and noise impact on fish and hydrobionts, changes in the bathymetric and hydrological characteristics of the riverbed, increased turbidity, secondary pollution of water and bottom sediments, and deterioration of the hydrochemical regime. The projected quarry will be located in the riverbed of the Irtysh in the Tobolsk District of the Tyumen Region, at a distance of 5 and 10 km upstream from two wintering holes - Nizhne-Filatovskaya and Nadtsinskaya, which are of great importance for preserving the aquatic biological resources. To prevent possible negative consequences for the fish population, including sturgeon species, it has been proposed to conduct monitoring studies. There is given a list of physical, chemical and biological indicators that should be monitored during the quarry operation: fish density, proportion of fish taxonomic groups and size groups, content of oxygen dissolved in water, content of heavy metals and oil products in water and sediments, turbidity, bathymetric characteristics. Using Horiba, a multi-parameter system of water quality assessment, and AsCor and PanCor hydroacoustic complexes there have been studied the initial indicators of water turbidity and fish density in the water area adjacent to the site of the projected quarry, as well as taxonomic composition of the fish population. Additionally, in order to minimize damage to fisheries, it has been proposed to limit the period of quarry operation by the time of its drying in the period of low water - from 2d decade of August to October.

scholarly journals DISTRIBUTION OF CASPIAN SPRATS IN THE NORTH-WESTERN PART OF THE CASPIAN SEA (BASED ON RESULTS OF HYDROACOUSTIC RESEARCH IN NOVEMBER 2018)

2019 ◽  
pp. 41-50
Author(s):  
Tatiana Vasilievna Pomogaeva
Keyword(s):  
Caspian Sea ◽  
Water Surface ◽  
Bottom Layer ◽  
Water Area ◽  
Middle Part ◽  
Average Density ◽  
Layer By Layer ◽  
The Caspian Sea ◽  
The North ◽  
Study Results

Since Caspian sprat today is a reserve fishery object, hydroacoustic studies are the main purpose of solving the problem of estimating concentrations, areas and terms of the organization of the Russian marine fishery. A promising fishing area is the region of the middle part of the Caspian Sea, off the Dagestan coast, which has been studied since 2011. As it was found during previous studies, the densest sprat schools form in the autumn period in the bottom layer. The present research focuses on Caspian sprat distribution in the western part of the Middle Caspian in November 2018. Hydroacoustic tacks covered a water area of 630 NM. The echo recordings of hydroacoustic surveys covering the water area at the depths 20-60 m were analyzed. The recordings were studied considering the response of sprat to the day and night light. Processing of hydroacoustic data was carried out in several stages: analytical viewing of echograms purposed to identify specific features of sprat; recording minimum and maximum values of echo intensity depending on the depth; data post-processing in SIMRAD BI-60 program. The distribution of Caspian sprats is represented totally from the water surface to the ground, and layer by layer, in layers of 10 meters from the water surface. It has been stated that in the surface layer there are practically no sprat schools. The maximum value of the average density (8.7 t / mile2) was registered in the bottom layer (40-50 m). The study results can be used in organization of Russian sprats fishing in the Caspian Sea.

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