The Caspian Sea is the greatest among the lakes of the earth with a surface of more than 400 thousand km3 and is a unique enclosed water reservoir. Situated on the juncture of European and Asian continents, the Caspian is stretched in the meridian direction for more than 1,200 km with an average width of 310 km. The shoreline length due to the water level variations is changeable and exceeds 6,000 km. The volume of the sea is estimated to be almost 80 thousand km3, which is more than 44% of the general lake water resources of the earth. The waters of the Caspian Sea wash the coasts of Azerbaijan, Russia, Kazakhstan, Turkrnenistan and the Islamic Republic of Iran and its basin involves the most important, densely populated regions of the European continent with developed industrial potential.
A unique flora and fauna, including 90% of the world’s sturgeon stock has been preserved in the Caspian till present. A deterioration in the ecological situation has first and foremost influenced the endemic fauna. The number of commercial fish (sturgeon, herring) has considerably been reduced, some fish species have been included into the Red Book, and two species have practically disappeared the zander and Caspian thorn fish.
The Caspian is divided into three uneven parts: North, Middle and South. The southern border of the North Caspian extends from the Chechen island to the Tub Karatan cape. The Middle Caspian is situated between this border on the line extending from the Sworn Rock island (Apsheron Peninsula) to the Kuulin cape on the eastern coast. The South Caspian is situated south of this border. The North Caspian has an average depth of 5 6 m, the Middle Caspian 190 m. The deepest water part is in the South Caspian 1025 m in the area east of the Kura Mouth, the shelf area in general is within 100 m here. The water border of the Republic, as well as the length and legal status of the water area, has not been defined until now. However, more than 800 km of the shoreline falls onto Azerbaijan.
The Caspian shoreline from the Samur River to the Apsheron Peninsula is a relatively straight line. There are no peninsulas or gulfs strongly cutting into the Caspian, and there are no islands. From the Apsheron to the Akstafachay River the shoreline is rather twisting: a number of protuberant capes and spits, together with the Kizil Agach Bay and a big group of islands, create a unique picture of this region. In the South, Caspian islands form archipelagoes: Apsheron (Zhiloy, Urnus, Peschany and others) and Baku (Bulla, Svinnoy, Duvanny, Glinany and others). The development of mud volcanoes is characteristic of the South Caspian. Almost all the islands of Baku are periodically active mud volcanoes. Eolian sandy (dunes, hillock sands, sand reaches) landscape and sandy beaches are dominant in the coastal area of the Middle and South Caspian. The distribution of vegetation groups depends upon the marine zone distribution, conditioned by chan ges in the water and salt regimes. Typically from the sea to the shore, parallel to the shoreline, vegetation groups consequently vary from primitive to more complicated as follows:
Vegetation groups in the coastal area of Apsheron are destroyed and do not form a dense cover. The plants are represented by species and subspecies of undemanding plants typical of dry semi deserts.
The vegetation of the coastal area of the South Caspian has some differences. The main type of vegetation is represented by Halocnemum, Halo stachys cane and Salicornia formations, which are deve loped on salines.
The Halocnemum vegetation occupies the main part of the territory. The main species is Halocnemum strobilaceum.
centers. Prior to the regulation of the Volga River (1951 1955) the average catch constituted 2.9 million metric centers (without sprat), including: big bony fish 1.08 million metric centers, vobla 0.79 million metric centers, herring 0.54 million metric centers, and sturgeon 0.12 million metric centers. The sturgeon catch during 1980 1990 decreased from 0.25 million metric centers to 0.13 million metric centers. In 1991, 4.05 million metric centers of fish were caught in the Caspian, of them sturgeon constituted 10.08 thousand tons; salmon 0.02 thousand tons; big bony fish 11.3 thousand
tons; herring 1.51 thousand tons; and sprat 365.16 thousand tons. centers. Prior to the regulation of the Volga River (1951 1955) the average catch constituted 2.9 million metric centers (without sprat), including: big bony fish 1.08 million metric centers, vobla 0.79 million metric centers, herring 0.54 million metric centers, and sturgeon 0.12 million metric centers. The sturgeon catch during 1980 1990 decreased from 0.25 million metric centers to 0.13 million metric centers. In 1991, 4.05 million metric centers of fish were caught in the Caspian, of them sturgeon constituted 10.08 thousand tons; salmon 0.02 thousand tons; big bony fish 11.3 thousand tons; herring 1.51 thousand tons; and sprat 365.16 thousand tons. During the following years the catch of commercial fish species kept decreasing on average by 10%. As is seen, the species composition of some catches changed sharply: sprat production significantly increased, but the catch of valuable commercial fish decreased by 9 10 times. At present, there is an even further decrease in the catches and a reduction in the density of valuable fish species.
The socio economic development of the whole Caspian region depends mostly on the state of the Caspian ecosystem and its natural resources. The ecological capacity of the water reservoir, characterizing the self purification ability of the ecosystem, is practically exhausted for the Caspian because the permanent income and the absence of flow leads to an accumulation of contaminating substances in seabed sediments. The Caspian ecological zone makes a great climate forming influence for the whole region, and the condition of the water reservoir is a determinant for the whole environment of the Republic.
Systematic water sampling in different parts of the Caspian basin show contamination by phenols, oil products, surfactant (synthetic surface active substances) and others. It should be noted that more that 12 billion m3 of contaminated sewage is discharged into the Caspian annually, 95% of which comes from the Volga river.
Azerbaijan has been taking measures to reduce environmental pollution. Only during the last decade, 59 water protecting measures have been undertaken and about 170 water treatment facilities have been constructed. As a result of these measures, the project capacity of the treatment facilities of the Republic constituted 1.28 million m3 / per 24 hours, the capacity of circulating and repeated consecutive water supply systems reached up to 4.46 million m3 per 24 hours. At first sight the taken measures enabled a decrease in the negative effects on the ecology of the Caspian, reduced the discharge of untreated sewage by half a million m3 per 24 hours. However, these measures did not take into account the increase in the sewage amount and turned out to be insufficient. Today Azerbaijan discharges about 0.3 billion of highly contaminated, and 300 million of nominally treated, sewage. As a result, these waters bring 4 thousand tons of oil products, 28 thousand tons of suspended substances, 500 550 thousand tons of solid residue, 74 thousand tons of sulfates, 150 thousand tons of chlorine, 300 tons of surfactant 5 tons of phenols and other substances hazardous to the ecosystem, to the sea.
Today in Azerbaijan six oil and gas extraction departments (OGED), seven drilling departments (which have more than 2,000 oi1 and gas wells on their books), over 400 stationary platforms, 180 km long stockades, 255 thousand km of underground and more than 1.5 tho
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