TO STUDY THE BIOECOLOGY OF CASPIAN SHRIMPS

2021 ◽  
pp. 98-102
Author(s):  
Kais M. Guseynov ◽  
Aysha Sh. Gasanova ◽  
Marina V. Khlopkova
Keyword(s):  
Caspian Sea ◽  
Regression Equations ◽  
The Caspian Sea ◽  
Macrobrachium Nipponense ◽  
The North ◽  
Current State ◽  
Palaemon Elegans ◽  
Near Future ◽  
The Relationship ◽  
Shrimp Population

Only two species of shrimps live in the Caspian Sea: Palaemon elegans and P. adspersus (Crustacea, Decapoda: Palaemonidae), which were introduced to the Caspian Sea in 1931-1934 during the introduction of mullets. Data on the biology of these species of shrimps are reflected only in the works by E.N. Kudelina (1950) and M.P. Marochkina (1980). This determines the relevance of research on the current state of the Caspian shrimp population. The material was collected in various areas of the Middle Caspian Sea in the summer-autumn period. Both species live up to five meters deep. P. elegans prefer coastal underwater objects with dense thickets, P. adspersus - open shallow waters with sandy-muddy soil. To the north of Makhachkala, P. elegans predominates, to the south, the number of both species is the same, and to the east, P. adspersus dominates. The characteristics of breeding females are presented, and the dependence of fecundity on the length of egg-bearing females is revealed. The absolute fecundity increased with the increase in the size of the females. Regression equations reflecting the relationship between fecundity and length of egg-bearing females of P. elegans and P. adspersus are calculated, expressed by power equations, respectively: E = 0.044947 · L265356 and E = 2.323 · L17.4, where: E - fecundity, L-length. In October 2017, in May and October 2018, several specimens of the subtropical freshwater shrimp Macrobrachium nipponense were found downstream of the Terek River. Probably, in the near future, the species composition of the Caspian shrimp will be replenished with another species.

scholarly journals Biology and current state of anchovy kilka (Clupeonella engrauliformis Borodin)

2020 ◽  
Vol 2020 (2) ◽  
pp. 45-51
Author(s):  
Vjacheslav Petrovich Razinkov ◽  
Yuriy Aleksandrovich Paritskiy ◽  
Yulia Nikolaevna Grozesku
Keyword(s):  
Survival Rate ◽  
Caspian Sea ◽  
Small Fish ◽  
Way Of Life ◽  
The Caspian Sea ◽  
Dynamics Of Abundance ◽  
Current State ◽  
Beroe Ovata ◽  
The Relationship ◽  
A New Species

In the Caspian Sea sprats is the name of the numerous small fish of herring family (Clupeonella). One of Clupeonella representatives is anchovy sprat. It differs from other types of kilka not only in appearance, but also in its way of life. A brief biology of the species and the state of ecosystem of the Caspian pelagic zone has been described. Anchovy kilka has been a leading targeted fish for over 50 years. Invading the Caspian Sea by ctenophore-mnemiopsis has undermined the stocks of anchovy sprats and caused the crisis of anchovy kilka fishing. Recently, there has been observed a slight increase in the number of the species. The survey materials confirm the increase in the number of juveniles in the studied catches. There are presented the materials from the last six years (2014–2019) of observations (eight research runs), shown the dynamics of abundance, biomass, spawning females, and total fertility of the population. Spawning efficiency and survival rate in early ontogenesis are analyzed. The relationship between kilka survival rate and the number of emerging generations is stated. Recommendations on restoring the stock of anchovy kilka are given. To restore the ecosystem of the Caspian Sea there has been proposed the invasion of a new species – ctenophore-beroe (Beroe ovata), which, due to the structure of its mouthparts eats only jelly-skinned (ctenophore-mnemiopsis, exceptionally) and can significantly reduce the number of ctenophore-mnemiopsis

CURRENT STATE FOR FOOD SUPPLY OF BENTHOPHAGIC FISH IN THE URAL RIVER DELTA AND THE NORTH PART OF THE CASPIAN SEA

2017 ◽  
pp. 54-61
Author(s):  
Leila Kamidullaevna Seydalieva
Keyword(s):  
Caspian Sea ◽  
Hediste Diversicolor ◽  
The Caspian Sea ◽  
The North ◽  
Current State ◽  
Chironomidae Larvae ◽  
North Part ◽  
Average Biomass ◽  
June July ◽  
Made In

The paper presents the results of the research held in spring-autumn, 2014. In the course of the research there were used complex field observations. There was determined qualitative composition of zoobenthos of the lower reaches and the delta of the Ural (13 taxons) and the North part of the Caspian Sea (33 taxons, main groups: crustaceans, molluscas and worms), quantity and biomass of main species and groups of zoobenthos. In the lower reaches of the Ural Oligochaeta worms made the largest group, Chironomidae larvae made a smoller group. In August average biomass of zoobenthos in the delta of the Ural made 16.66 g/m2. In the North part of the Caspian Sea maximum domination index belonged to Oligochaeta - 12.5; Hypanis vitrea vitrea had 7.1; Chironomidae larvae - 6.4. Corophiidae were numerous , with domination index 6.3; Balanus improvisus had 6.2; Hediste diversicolor - 4.7. Domination index of other bottom organisms didn’t exceed 3.8. Average biomass of bottom organizms in the North Part of the Caspian Sea made: in June - July 20.48 g/m2, in September 9.212 g/m2. Stern zoobenthos took (without taking into account large molluscas and barnacles) 8.14 and 3.8 g/m2, respectively. The data obtained can be used for determining methods of saving and stable use of fish resources in the Ural-Caspian Sea basin.

ICE CONDITIONS IN THE NORTH-WESTERN PART OF THE CASPIAN SEA IN THE MODERN PERIOD

2020 ◽  
Vol 19 (6) ◽  
pp. 4-17
Author(s):  
Nepomenko Leonid ◽  
◽  
Popova Natalia ◽  
Zubanov Stepan ◽  
Ostrovskaya Elena ◽  
...  
Keyword(s):  
Caspian Sea ◽  
The Caspian Sea ◽  
The North ◽  
Modern Period ◽  
Ice Conditions ◽  
North Western

scholarly journals Legal Status Of The Caspian Sea: History And Present

2012 ◽  
Vol 6 ◽  
Author(s):  
Ardak Kapyshev
Keyword(s):  
Caspian Sea ◽  
Legal Status ◽  
Oil Fields ◽  
Present Stage ◽  
The Caspian Sea ◽  
Interstate Relations ◽  
The Usa ◽  
History Of ◽  
The Right ◽  
Near Future

At  the  present  stage  one  of  the  unsolved   problems in  interstate relations of  Caspian bordering countries is defining international­legal status of the Caspian Sea. It is noted in the article that this problem is not a new one at all. The history of “division” of the Caspian Sea begins in the ancient age, namely in VIII century. It is underlined that the basic stumbling block  is the position of Iran on the right to use the Caspian Sea, and also occurrence of extra regional players, such as  the USA, China, etc. First of  all, it is connected with rich oil fields and other minerals, and also with convenient geopolitical and geostrategic position. The only way to worry out the international­legal delimitation of the Caspian Sea problem is a negotiating process. By now, despite of  certain disagreements on  legal status of  the Caspian Sea, five Caspian bordering countries managed to achieve certain progress, admitting the possibility of applying the principle of sectorial sectioning on the Caspian Sea.  Clear proof  of  it is the agreements on  division of ground on the northern part of Caspian Sea signed between Kazakhstan, Russia and Azerbaijan. It is important that Kazakhstan, Russia, Azerbaijan and Turkmenistan clearly stated their positions and agreed to make a compromise in their official statements. More than likely, in the near future Iran will soften its position, considering its present  situation and   strained relations with the USA. It has been alleged that the constructive  dialog  already  started; everything depends on  the mobility,  concurrency and rationality of actions of all Caspian bordering countries.

scholarly journals The length of coastlines in Ptolemy's Geography and in ancient periploi

2018 ◽  
Vol 9 (1) ◽  
pp. 9-24 ◽  
Author(s):  
Dmitry A. Shcheglov
Keyword(s):  
Caspian Sea ◽  
Simple Explanation ◽  
The Caspian Sea ◽  
The North ◽  
True Value ◽  
The Earth ◽  
Erroneous Estimate ◽  
Remarkable Agreement ◽  
East West

Abstract. The lengths of the coastlines in Ptolemy's Geography are compared with the corresponding values transmitted by other ancient sources, presumably based on some lost periploi (literally "voyages around or circumnavigations", a genre of ancient geographical literature describing coastal itineraries). The comparison reveals a remarkable agreement between them, suggesting that Ptolemy relied much more heavily on these or similar periploi than it used to be thought. Additionally, a possible impact of Ptolemy's erroneous estimate of the circumference of the Earth is investigated. It is argued that this error resulted in two interrelated distortions of the coastal outlines in Ptolemy's Geography. First, the north–south stretches of the coast that were tied to particular latitudes are shown compressed relative to the distances recorded in other sources in roughly the same proportion to which Ptolemy's circumference of the Earth is underestimated relative to the true value. Second, in several cases this compression is compensated by a proportional stretching of the adjacent east–west coastal segments. In particular, these findings suggest a simple explanation for the strange shape of the Caspian Sea in Ptolemy's Geography.

scholarly journals Mental health services in Azerbaijan

2004 ◽  
Vol 1 (3) ◽  
pp. 16-17
Author(s):  
Fuad Ismayilov
Keyword(s):  
Mental Health ◽  
Soviet Union ◽  
Mental Health Services ◽  
Health Services ◽  
Caspian Sea ◽  
Total Population ◽  
The Other ◽  
The Caspian Sea ◽  
The North ◽  
The Soviet Union

Azerbaijan is a nation with a Turkic population which regained its independence after the collapse of the Soviet Union in 1991. It has an area of approximately 86 000 km2. Georgia and Armenia, the other countries comprising the Transcaucasian region, border Azerbaijan to the north and west, respectively. Russia also borders the north, Iran and Turkey the south, and the Caspian Sea borders the east. The total population is about 8 million. The largest ethnic group is Azeri, comprising 90% of the population; Dagestanis comprise 3.2%, Russians 2.5%, Armenians 2% and others 2.3%.

scholarly journals Geothermal field and geology of the Caspian Sea region

2019 ◽  
pp. 104-118 ◽  
Author(s):  
Vladimir I. Zui ◽  
Siamak Mansouri Far Far
Keyword(s):  
Heat Flow ◽  
Flow Pattern ◽  
Caspian Sea ◽  
Sedimentary Basins ◽  
Geothermal Field ◽  
Flow Density ◽  
General Tendency ◽  
The Caspian Sea ◽  
Northern Iran ◽  
The North

The Caspian Sea and adjacent areas form the vast oil and gas-bearing megabasin. It consists of North Caspian, Middle Caspian, and South Caspian sedimentary basins. The granite-metamorphic basement of the basins becomes from north to south younger in the direction from Early Precambrian to Early Cimmerian age. It represents a transitional zone from the southern edge of the East European Craton to Alpine folding. Geothermal investigations have been carried out both in hundreds of deep boreholes and within the Caspian Sea and a few preliminary heat flow maps were published for the Caspian Sea region. All they excluded from consideration the southern part of the region within Iranian national borders. We prepared a new heat flow map including the northern Iran. The purpose of the article is to consider heat flow pattern within the whole Caspian Sea region including its southern part. Two vast high heat flow anomalies above 100 mW/m2 distinguished in the map: within the southwestern Iran and in waters of the Caspian Sea to the North of the Apsheron Ridge, separated by elongated strip of heat flow below 50 –55 mW/m 2 . A general tendency of heat flow from growing was distinguished from the Precambrian crustal blocks of the North Caspian Depression to the Alpine folding within the territory of Iran. Analysis of the heat flow pattern is discussed and two heat flow density profiles were compiled.

scholarly journals Numerical modelling of the Caspian Sea tides

Ocean Science ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 209-219
Author(s):  
Igor P. Medvedev ◽  
Evgueni A. Kulikov ◽  
Isaac V. Fine
Keyword(s):  
Caspian Sea ◽  
Ocean Model ◽  
Tidal Range ◽  
The South ◽  
Tidal Dynamics ◽  
The Caspian Sea ◽  
Sea Levels ◽  
The North ◽  
Anticlockwise Rotation ◽  
Diurnal Tides

Abstract. The Caspian Sea is the largest enclosed basin on Earth and a unique subject for the analysis of tidal dynamics. Tides in the basin are produced directly by the tide-generating forces. Using the Princeton Ocean Model (POM), we examine details of the spatial and temporal features of the tidal dynamics in the Caspian Sea. We present tidal charts of the amplitudes and phase lags of the major tidal constituents, together with maps of the form factor, tidal range, and tidal current speed. Semi-diurnal tides in the Caspian Sea are determined by a Taylor amphidromic system with anticlockwise rotation. The largest M2 amplitude is 6 cm and is located in Türkmen Aylagy (called Turkmen Bay hereafter). For the diurnal constituents, the Absheron Peninsula separates two individual amphidromes with anticlockwise rotation in the north and in the south. The maximum K1 amplitudes (up to 0.7–0.8 cm) are located in (1) the south-eastern part of the basin, (2) Türkmenbaşy Gulf, (3) Mangyshlak Bay; and (4) Kizlyar Bay. As a result, the semi-diurnal tides prevail over diurnal tides in the Caspian Sea. The maximum tidal range, of up to 21 cm, has been found in Turkmen Bay. The strongest tidal currents have been located in the straits to the north and south of Ogurja Ada, where speeds reach 22 and 19 cm s−1, respectively. Numerical simulations of the tides using different mean sea levels (within a range of 5 m) indicate that spatial features of the Caspian Sea tides are strongly sensitive to changes in mean sea level.

scholarly journals DISTRIBUTION AND NUTRITION OF RUSSIAN STURGEON JUVENILES ( АCIPENSER GUELDENSTAEDTII, АCIPENSERIDAE) IN THE NORTH-WESTERN PART OF THE CASPIAN SEA

2019 ◽  
Vol 20 (3) ◽  
pp. 326-338
Author(s):  
S.V. Shipulin ◽  
◽  
S.V. Kanat’ev ◽  
I.N. Lepilina ◽  
E’.Ju. Tikhonova ◽  
...  
Keyword(s):  
Caspian Sea ◽  
Russian Sturgeon ◽  
The Caspian Sea ◽  
The North ◽  
North Western
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