scholarly journals Spatio-temporal variability of organic matter contents in the waters of the Caspian Sea

2019 ◽  
Vol 46 (1) ◽  
pp. 70-81
Author(s):  
A. I. Agatova ◽  
N. I. Torgunova ◽  
E. A. Serebryanikova ◽  
L. K. Dukhova
Keyword(s):  
Organic Matter ◽  
Hydrogen Sulfide ◽  
Caspian Sea ◽  
Vertical Mixing ◽  
Qualitative Change ◽  
Border Region ◽  
The Caspian Sea ◽  
Sea Levels ◽  
The North ◽  
Spatio Temporal

We analyzed spatio-temporal changes in concentrations and elemental compositions of dissolved organic matter in the waters of the Caspian Sea over the period 2010–2015. These studies showed that over the past 5 years of lowering of sea levels, mean concentrations of Corg and Norg remained virtually unchanged, whereas concentrations of Porg decreased more than three-fold, suggesting a qualitative change in organic matter. Based on data averages, concentrations of Corg, Norg, and Porg in Southern waters were slightly higher than in the North and Middle-Caspian waters during the monitoring period. In deep areas at the border region of hydrogen sulfide occurrence, concentrations of Corg, Norg, and Porg increase. Hence, the presence of hydrogen sulfide in the deep waters of the Derbent and South Caspian basins, and the corresponding increase in organic matter contents, indicates no radical improvement of vertical mixing of the sea in these areas during the eight years of our regression model. Moreover, according to the carbohydrate distribution, organic substances of petroleum hydrocarbons contribute considerably to a common pool.

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 Analysis of the Content of Hydrogen Sulfide in the Air of the City of Atyrau

2021 ◽  
Vol 16 (3) ◽  
pp. 479-483
Author(s):  
Mansiya Yessenamanova ◽  
Zhanar Yessenamanova ◽  
Anar Tlepbergenova ◽  
Gaukhar Batyrbayeva
Keyword(s):  
Hydrogen Sulfide ◽  
Caspian Sea ◽  
Maximum Permissible Concentration ◽  
Air Pollutant ◽  
Oil Refinery ◽  
The Caspian Sea ◽  
Atmospheric Air ◽  
The North ◽  
The Republic ◽  
The City

This study is aimed at analyzing the content of hydrogen sulfide in the air of the city of Atyrau, located in the northern part of the Caspian Sea of the Republic of Kazakhstan. The analysis was carried out on the basis of monitoring the indicators of the Republican State Enterprise "Kazhydromet" from 8 points located in different directions from the Atyrau oil refinery. Measurements of atmospheric air pollution are made by the GANK-4AR gas analyzer designed for continuous automatic measurement of concentrations of pollutants in the atmospheric air. Hydrogen sulfide was selected as an indicator air pollutant. Atyrau oil refinery is the main object of pollution of the territory of the city of Atyrau, located in the western part of the Republic of Kazakhstan, on the shore of the Caspian Sea. The results obtained show that the content of hydrogen sulfide in the territory of the city of Atyrau in most places shows an excess of the maximum permissible concentration. Especially the excess is observed in the north-western part up to 4-8 maximum permissible concentrations. At two points (in the north-eastern and western parts), the content of hydrogen sulfide did not exceed the maximum permissible concentration.

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 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 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

scholarly journals STATE OF POPULATION OF PIKE PERCH OF THE LOWER FLOW OF THE URAL RIVER

2018 ◽  
pp. 83-89
Author(s):  
Sergey Vladimirovich Kuzmenko ◽  
Arkadii Fedorovich Sokolsky ◽  
Alexander Nickolaevich Nevalennyy ◽  
Nikolay Nikolayevich Popov
Keyword(s):  
Caspian Sea ◽  
Fishing Ground ◽  
Commercial Fishing ◽  
The Caspian Sea ◽  
Foreign Markets ◽  
North East ◽  
The North ◽  
Pike Perch ◽  
Exploration And Production ◽  
Commercial Species

In domestic and foreign markets a great demand for pike perch is caused by the fact that its meat is a digestible and dietetic product. Due to growing scales of exploration and production of oil, as well as of poaching in the last years pikeperch and other species suffer from anthropogenic load. In 1990 spike perch catches reached 4.49.000 tons and made 1/3 of total catch of semi anadromous and river fish. During the last decade pike perch catches have decreased in the Ural-Caspian region up to 380 t, according to data of 2016. The study of pike perch populations on fishing zones of the Ural (delta, Malaya Dambinskaya fishing ground) covered the data obtained in 2010-2016. There have been studied migrating periods of pike perch to the spawning grounds. Since 2011 there has been stated a drastic decrease of sire number and a much less catch of pike perch per one casting in autumn, which was caused by the permission for fishing in the coastal part of the Caspian Sea. According to the research data, there have been given size-weight parameters of pike-perch producers in the Ural river during 10 years (2006-2016). The tendency to juvenation of spawning pike perch species is stated due to increasing share of the first spawning species, as well as due to decreasing number of male species in the catches as their age increased. Fultin and Clark’s condition coefficients are shown. Importance of pike perch as a commercial species in the ecosystem of the Ural-Caspian fishery zone contributes to define the following recommendations on saving and restoring pike perch population: to reduce commercial catches in the estuarine area of the Ural; to forbid commercial fishing in the coastal area of the north-east part of the Caspian Sea; to intensify fishery inspection in the Urals.

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