The Caspian Sea is freshwater. Caspian Sea or lake? Large bays of the Caspian Sea

The Caspian Sea is located between Asia and Europe. This is the largest salt sea-lake, located on the territory of Kazakhstan, Russia, Azerbaijan, Iran and Turkmenistan. Currently, its level is 28 meters below the level of the World Ocean. The depth of the Caspian Sea is quite large. The area of ​​the reservoir is 371 thousand square kilometers.

Story

About five million years ago, the sea divided into small bodies of water, including the Black and Caspian seas. After these events they united and separated. About two million years ago Caspian lake was cut off from the World Ocean. This period is considered the beginning of its formation. Throughout history, the reservoir has changed its contours several times, and the depth of the Caspian Sea has also changed.

Now the Caspian is the largest inland body of water, containing about 44% of the planet’s lake waters. Despite the changes taking place, the depth of the Caspian Sea did not change very much.

Once it was called Khvalian and Khazar, and the tribes of horse breeders gave it another name - Caspian. This is the name of the tribe living on the southwestern shore of the reservoir. In total, during its existence the lake had more than seventy names, here are some of them:

  1. Abeskunskoe.
  2. Derbent.
  3. Saraiskoe.
  4. Xihai.
  5. Dzhurdzhanskoe.
  6. Hyrcanian.

Depth and relief

The relief and features of the hydrological regime divide the sea-lake into northern, middle and southern parts. Over the entire area of ​​the Caspian Sea, the depth is on average 180-200 m, but the relief in different parts is different.

The northern part of the reservoir is shallow. Here the depth of the Caspian Sea-lake is approximately 25 meters. In the middle part of the Caspian there are very deep depressions, continental slopes, shelves. Here average depth is 192 meters, and in the Derbent depression - about 788 meters.

The greatest depth of the Caspian Sea is in the South Caspian depression (1025 meters). Its bottom is flat, and in the northern part of the depression there are several ridges. It is here that the maximum depth of the Caspian Sea is noted.

Coastline Features

Its length is seven thousand kilometers. Northern part coastline It is a lowland, with mountains in the south and west, and hills in the east. The spurs of Elbrus and the Caucasus Mountains approach the shores of the sea.

The Caspian has large bays: Kazakh, Kizlyar, Mangyshlak, Kara-Bogaz-Gol, Krasnovodsk.

If you go on a cruise from north to south, the length of the route will be 1200 kilometers. In this direction, the reservoir has an elongated shape, and from west to east the width of the sea is different. At its narrowest point it is 195 kilometers, and at its widest it is 435 kilometers. The average width of the reservoir is 315 km.

The sea has several peninsulas: Mangyshlak, Buzachi, Miankale and others. There are also several islands here. The largest are Chygyl, Kur-Dashi, Gum, Dash, and Tyuleni Islands.

Pond food

About one hundred and thirty rivers flow into the Caspian Sea. Most of them flow in the north and west. Main river flowing into the sea is the Volga. Approximately ninety percent of the volume of runoff comes from three large rivers: the Volga (80%), Kura (6%) and Ural (5%). Five percent are from Terek, Sulak and Samur, and the remaining four are brought by small rivers and streams of Iran.

Resources of the Caspian Sea

The reservoir has amazing beauty, a variety of ecosystems and a rich supply of natural resources. When there are frosts in its northern part, magnolias and apricots bloom in the south.

Relict flora and fauna have been preserved in the Caspian Sea, including the largest school of sturgeon fish. As it evolved, the marine flora changed more than once, adapting to salinity and desalination. As a result, these waters became rich in freshwater species, but few in marine species.

After the Volga-Don Canal was built, new species of algae appeared in the reservoir, which were previously found in the Black and Azov Seas. Now in the Caspian Sea there are 854 species of animals, of which 79 are vertebrates, and over 500 species of plants. This unique sea-lake produces up to 80% of the catch of all sturgeon in the world and approximately 95% of black caviar.

Five species of sturgeon are found in the Caspian Sea: stellate sturgeon, thorn, sterlet, beluga and sturgeon. Beluga is the largest representative of the species. Its weight can reach a ton, and its length can be five meters. In addition to sturgeon, herring, salmon, kutum, roach, asp and other types of fish are caught in the sea.

Of the mammals in the Caspian Sea, only the local seal is found, which is not found in other bodies of water in the world. It is considered the smallest on the planet. Its weight is about a hundred kilograms, and its length is 160 centimeters. The Caspian region is a major route for bird migration between Asia, the Middle East and Europe. Every year, approximately 12 million birds fly over the sea during migration (south in spring and north in autumn). In addition, another 5 million remain in these places for the winter.

The most great wealth The Caspian Sea has huge reserves of oil and gas. Geological exploration in the region has discovered large deposits of these minerals. Their potential puts local reserves in second place in the world after

, Kura

42° N. w.  51° east d. HGIOL

Caspian Sea- the largest closed body of water on Earth, which can be classified as the largest closed lake, or as a full-fledged sea, due to its size, and also because its bed is composed of oceanic-type crust. Located at the junction of Europe and Asia. The water in the Caspian Sea is brackish, from 0.05 ‰ near the mouth of the Volga to 11-13 ‰ in the southeast. The water level is subject to fluctuations, according to 2009 data it was 27.16 m below sea level. The area of ​​the Caspian Sea is currently approximately 371,000 km², the maximum depth is 1025 m.

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Etymology

Geographical location

The Caspian Sea is located at the junction of Europe and Asia. The length of the sea from north to south is approximately 1200 kilometers (36°34"-47°13" N), from west to east - from 195 to 435 kilometers, on average 310-320 kilometers (46°-56° in .d.).

According to physical and geographical conditions, the Caspian Sea is conventionally divided into three parts - the Northern Caspian (25% of the sea area), the Middle Caspian (36%) and the Southern Caspian (39%). The conditional border between the Northern and Middle Caspian runs along the line Chechen Island - Cape Tyub-Karagan, between the Middle and Southern Caspian - along the line Chilov Island - Cape Gan-Gulu.

Coast

The territory adjacent to the Caspian Sea is called the Caspian region.

Peninsulas

  • Absheronsky Peninsula, located on west coast Caspian Sea on the territory of Azerbaijan, at the northeastern end of the Greater Caucasus, on its territory the cities of Baku and Sumgayit are located
  • Mangyshlak, located on the eastern coast of the Caspian Sea, on the territory of Kazakhstan, on its territory is the city of Aktau

Islands

There are about 50 large and medium-sized islands in the Caspian Sea with a total area of ​​approximately 350 square kilometers.

Largest islands:

Bays

Large bays:

Kara-Bogaz-Gol

On the eastern coast is the salt lake Kara-Bogaz-Gol, which until 1980 was a bay-lagoon of the Caspian Sea, connected to it by a narrow strait. In 1980, a dam was built separating Kara-Bogaz-Gol from the Caspian Sea, and in 1984 a culvert was built, after which the level of Kara-Bogaz-Gol dropped by several meters. In 1992, the strait was restored, through which water flows from the Caspian Sea to Kara-Bogaz-Gol and evaporates there. Every year, 8-10 cubic kilometers of water (according to other sources - 25 cubic kilometers) and about 15 million tons of salt flow into Kara-Bogaz-Gol from the Caspian Sea.

Rivers flowing into the Caspian Sea

130 rivers flow into the Caspian Sea, of which 9 rivers have a delta-shaped mouth. Large rivers flowing into the Caspian Sea are Volga, Terek, Sulak, Samur (Russia), Ural, Emba (Kazakhstan), Kura (Azerbaijan), Atrek (Turkmenistan), Sefidrud (Iran). The largest river flowing into the Caspian Sea is the Volga, its average annual flow is 215-224 cubic kilometers. The Volga, Ural, Terek, Sulak and Emba provide up to 88-90% of the annual flow into the Caspian Sea.

Basin of the Caspian Sea

Coastal states

According to the Intergovernmental Economic Conference of the Caspian States:

The Caspian Sea washes the shores of five coastal states:

Cities on the Caspian Sea coast

On Russian coast The cities of Lagan, Makhachkala, Kaspiysk, Izberbash, Dagestanskie Ogni and the southernmost city of Russia, Derbent, are located. port city The Caspian Sea is also considered Astrakhan, which, however, is not located on the shores of the Caspian Sea, but in the Volga delta, 60 kilometers from north coast Caspian Sea.

Physiography

Area, depth, volume of water

The area and volume of water in the Caspian Sea varies significantly depending on fluctuations in water levels. At a water level of −26.75 m, the area is approximately 371,000 square kilometers, the volume of water is 78,648 cubic kilometers, which is approximately 44% of the world's lake water reserves. The maximum depth of the Caspian Sea is in the South Caspian depression, 1025 meters from its surface level. In terms of maximum depth, the Caspian Sea is second only to Baikal (1620 m) and Tanganyika (1435 m). The average depth of the Caspian Sea, calculated from the bathygraphic curve, is 208 meters. At the same time, the northern part of the Caspian Sea is shallow, its maximum depth does not exceed 25 meters, and the average depth is 4 meters.

Water level fluctuations

Flora

The flora of the Caspian Sea and its coast is represented by 728 species. The predominant plants in the Caspian Sea are algae - blue-green, diatoms, red, brown, characeae and others, and flowering plants - zoster and ruppia. In origin, the flora is predominantly of Neogene age, however, some plants were brought into the Caspian Sea by humans deliberately, or on the bottoms of ships.

Story

Origin

The Caspian Sea is of oceanic origin - its bed is composed of oceanic-type crust. 13 million l. n. the resulting Alps separated the Sarmatian Sea from the Mediterranean. 3.4 - 1.8 million l. n. (Pliocene) there was the Akchagyl Sea, the sediments of which were studied by N. I. Andrusov. It was originally formed on the site of the dried-up Pontic Sea, from which Lake Balakhanskoe (in the southern Caspian Sea) remained. The Akchagyl transgression was replaced by the Domashkin regression (a drop of 20 - 40 m from the level of the Akchagyl basin), accompanied by strong desalination sea ​​waters, which is due to the cessation of the flow of sea (ocean) waters from the outside. After a short Domashkin regression at the beginning of the Quaternary period (Eopleistocene), the Caspian Sea is almost restored in the form of the Absheron Sea, which covers the Caspian Sea and floods the territories of Turkmenistan and the Lower Volga region. At the beginning of the Absheron transgression, the basin turns into a brackish water body. The Absheron Sea exists from 1.7 to 1 million years ago. The beginning of the Pleistocene in the Caspian Sea was marked by a long and deep Turkic regression (-150 m to −200 m), corresponding to the Matuyama-Brunhes magnetic reversal (0.8 million years ago). The water mass of the Turkian basin with an area of ​​208 thousand km² was concentrated in the South Caspian and part of the Middle Caspian basins, between which there was a shallow strait in the area of ​​the Absheron threshold. In the early Neopleistocene, after the Turkic regression, there existed an isolated Early Baku and a Late Baku (level up to 20 m) drainage basins (approx. 400 thousand years ago). The Vened (Mishovdag) regression divided the Baku and Urundzhik (middle Neopleistocene, up to −15 m) transgressions at the end of the early - beginning of the late Pleistocene (basin area - 336 thousand km²). Between the marine Urundzhik and Khazar deposits, a large deep Cheleken regression (up to −20 m) was noted, corresponding to the optimum of the Likhvin interglacial (350-300 thousand years ago). In the Middle Neopleistocene there were basins: early Khazar (200 thousand years ago), early Khazar middle (level up to 35-40 m) and early Khazar late. In the late Neopleistocene, there was an isolated late Khazar basin (level up to −10 m, 100 thousand years ago), after which a small Chernoyarsk regression occurred in the second half - the end of the Middle Pleistocene (thermoluminescent dates 122-184 thousand years ago), in in turn, replaced by the Hyrcanian (Gyurgyan) basin.

The deep long-term Atelian regression of the mid-Late Pleistocene at the initial stage had a level of −20 - −25 m, at the maximum stage −100 - −120 m, at the third stage - −45 - −50 m. At the maximum, the basin area is reduced to 228 thousand km² . After Atel regression (−120 - −140 m), approx. 17 thousand l. n. The early Khvalynian transgression began - up to + 50 m (the Manych-Kerch Strait was functioning), which was interrupted by the Eltonian regression. The Early Khvalynsky II basin (level up to 50 m) was replaced at the beginning of the Holocene by a short-term Enotayev regression (from −45 to −110 m), coinciding in time with the end of the Preboreal and the beginning of the Boreal. The Enotayevskaya regression gave way to the Late Khvalynskaya transgression (0 m). The Late Khvalynian transgression was replaced in the Holocene (ca. 9-7 thousand years ago or 7.2-6.4 thousand years ago) by the Mangyshlak regression (from −50 to −90 m). The Mangyshlak regression gave way during the first phase of interglacial cooling and humidification (Atlantic period) to the New Caspian transgression. The New Caspian basin was brackish-water (11-13 ‰), warm-water and isolated (level up to −19 m). At least three cycles of transgressive-regressive phases have been recorded in the development of the Novo-Caspian basin. The Dagestan (Gousan) transgression previously belonged to the initial stage of the New Caspian era, however, the absence of a leading New Caspian form in its sediments Cerastoderma glaucum (Cardium edule) gives grounds for identifying it as an independent transgression of the Caspian Sea. The Izberbash regression, separating the Dagestan and the Neo-Caspian transgressions of the Caspian Sea itself, occurred between 4.3 and 3.9 thousand years ago. Judging by the structure of the Turali section (Dagestan) and radiocarbon analysis data, transgressions were noted twice - about 1900 and 1700 years ago.

Anthropological and cultural history of the Caspian Sea

Shipping

Shipping is developed in the Caspian Sea. On the Caspian Sea there are ferry crossings, in particular, Baku - Turkmenbashi, Baku - Aktau, Makhachkala - Aktau. The Caspian Sea has a shipping connection with Sea of ​​Azov through the rivers Volga, Don and the Volga-Don Canal.

Fishing and seafood production

Fishing (sturgeon, bream, carp, pike perch, sprat), caviar production, as well as seal fishing. More than 90 percent of the world's sturgeon catch occurs in the Caspian Sea. In addition to industrial mining, illegal mining of sturgeon and their caviar flourishes in the Caspian Sea.

Recreational resources

Natural environment of the Caspian coast with sandy beaches, mineral waters and healing mud in the coastal zone creates good conditions for relaxation and treatment. At the same time, according to the degree of development of resorts and the tourism industry Caspian coast noticeably loses to the Black Sea coast of the Caucasus. At the same time, in recent years, the tourism industry has been actively developing on the coasts of Azerbaijan, Iran, Turkmenistan and Russian Dagestan. Azerbaijan is actively developing resort area in the Baku region. A world-class resort has now been created in Amburan, another modern tourist complex is being built in the area of ​​the village of Nardaran, holidays in the sanatoriums of the villages of Bilgah and Zagulba are very popular. A resort area is also being developed in Nabran, in northern Azerbaijan. However high prices, in general, the low level of service and lack of advertising lead to the fact that there are almost no foreign tourists. The development of the tourism industry in Turkmenistan is hampered by a long-term policy of isolation, in Iran - by Sharia laws, due to which mass holidays of foreign tourists on the Caspian coast of Iran are impossible.

Environmental issues

Environmental problems of the Caspian Sea are associated with water pollution as a result of oil production and transportation on the continental shelf, the flow of pollutants from the Volga and other rivers flowing into the Caspian Sea, the life activity of coastal cities, as well as the flooding of individual objects due to rising levels of the Caspian Sea. Predatory hunting of sturgeon and their caviar, rampant poaching lead to a decrease in the number of sturgeon and to forced restrictions for their production and export.

Legal status

After the collapse of the USSR, the division of the Caspian Sea has long been and still remains the subject of unresolved disagreements related to the division of Caspian shelf resources - oil and gas, as well as biological resources. For a long time, negotiations were ongoing between the Caspian states on the status of the Caspian Sea - Azerbaijan, Kazakhstan and Turkmenistan insisted on dividing the Caspian along the median line, Iran insisted on dividing the Caspian by one-fifth between all Caspian states.

In relation to the Caspian Sea, the key is the physical-geographical circumstance that it is a closed inland body of water that does not have a natural connection with the World Ocean. Accordingly, the norms and concepts of international maritime law, in particular, the provisions of the 1982 UN Convention on the Law of the Sea, should not automatically apply to the Caspian Sea. Based on this, in relation to the Caspian Sea it would be unlawful to apply such concepts as “territorial sea”, “exclusive economic zone”, “continental shelf”, etc.

The current legal regime of the Caspian Sea was established by the Soviet-Iranian treaties of 1921 and 1940. These treaties provide for freedom of navigation throughout the sea, freedom of fishing with the exception of ten-mile national fishing zones and a ban on vessels flying the flag of non-Caspian states sailing in its waters.

Negotiations about legal status The Caspian Sea is currently ongoing.

Delineation of sections of the Caspian seabed for subsoil use

The Russian Federation concluded an agreement with Kazakhstan on delimiting the bottom of the northern part of the Caspian Sea in order to exercise sovereign rights to subsoil use (dated July 6, 1998 and the Protocol thereto dated May 13, 2002), an agreement with Azerbaijan on delimiting adjacent areas of the bottom of the northern part of the Caspian Sea (dated September 23, 2002), as well as the trilateral Russian-Azerbaijani-Kazakh agreement on the junction point of the demarcation lines of adjacent sections of the Caspian Sea bottom (dated May 14, 2003), which established geographical coordinates dividing lines limiting the areas of the seabed within which the parties exercise their sovereign rights in the field of exploration and production of mineral resources.

Caspian Sea

The Caspian Sea is one of the most amazing closed bodies of water on Earth.


Over the centuries, the sea has changed more than 70 names. The modern one came from the Caspians - tribes inhabiting the central and southeastern part of Transcaucasia 2 thousand years BC.
Geography of the Caspian Sea

The Caspian Sea is located at the junction of Europe and Asia and geographical location is divided into the Southern, Northern and Middle Caspian.
The middle and northern part of the sea belongs to Russia, the southern to Iran, the eastern to Turkmenistan and Kazakhstan, and the southwestern to Azerbaijan.

For many years, the Caspian states have been dividing the Caspian waters among themselves, and quite sharply at that.

Caspian sea map

Lake or sea?


In fact, the Caspian Sea is the world's largest lake, but has a number of marine signs.
These include: a large body of water, strong storms with high waves, high and low tides.

But the Caspian Sea does not have a natural connection with the World Ocean, which makes it impossible to call it a sea.
At the same time, thanks to the Volga and artificially created channels, such a connection appeared.

The salinity of the Caspian Sea is 3 times lower than the usual sea salinity, which does not allow the reservoir to be classified as a sea.

There were times when Caspian seas was truly part of the oceans.
Several tens of thousands of years ago the Caspian Sea was connected to the Sea of ​​Azov, and through it to the Black and Mediterranean.
As a result of long-term processes occurring in the earth's crust, Caucasus Mountains, which isolated the reservoir.
The connection between the Caspian and Black Seas was carried out for a long time through the strait (Kuma-Manych depression) and gradually ceased.

Physical quantities

Area, volume, depth


The area, volume and depth of the Caspian Sea are not constant and directly depend on the water level.
On average, the area of ​​the reservoir is 371,000 km², the volume is 78,648 km³ (44% of all world lake water reserves).

The depth of the Caspian Sea in comparison with lakes Baikal and Tanganyika


The average depth of the Caspian Sea is 208 m; the northern part of the sea is considered the shallowest. The maximum depth is 1025 m, noted in the South Caspian depression.
In depth, the Caspian Sea is second only to Baikal and Tanganyika.

The length of the lake from north to south is about 1200 km, from west to east on average 315 km. The length of the coastline is 6600 km, with islands - about 7 thousand km.

Shores


Mostly, the coast of the Caspian Sea is low and smooth.
In the northern part- strongly indented by the river channels of the Urals and Volga. The swampy shores here are located very low.
Eastern Shores adjacent to semi-desert zones and deserts, covered with limestone deposits.
The most winding banks are in the west in the region Absheron Peninsula, and in the east - in the area of ​​the Kazakh Gulf and Kara-Bogaz-Gol.

Sea water temperature

Temperature of the Caspian Sea at different times of the year


Average water temperature in winter in the Caspian Sea it ranges from 0 °C in the northern part to +10 °C in the southern part.
In Iranian waters, the temperature does not drop below +13 °C.
With the onset of cold weather, the shallow northern part of the lake is covered with ice, which lasts for 2-3 months. The thickness of the ice cover is 25-60 cm, at especially low temperatures it can reach 130 cm. In late autumn and winter, drifting ice floes can be observed in the north.

In summer average temperature The surface water temperature in the sea is + 24 °C.
In most parts the sea warms up to +25 °C…+30 °C.
Warm water and beautiful sandy, occasionally shell and pebble beaches create excellent conditions for a good beach holiday.
In the eastern part of the Caspian Sea near the city of Begdash in summer months saved abnormal low temperature water.

Nature of the Caspian Sea

Islands, peninsulas, bays, rivers


The Caspian Sea includes about 50 large and medium-sized islands, total area of which is 350 km².
The largest of them are: Ashur-Ada, Garasu, Gum, Dash and Boyuk-Zira. The largest peninsulas are: Agrakhansky, Absheronsky, Buzachi, Mangyshlak, Miankale and Tyub-Karagan.

Tyuleniy Island in the Caspian Sea, part of the Dagestan Nature Reserve


To the largest bays of the Caspian Sea include: Agrakhansky, Kazakh, Kizlyarsky, Dead Kultuk and Mangyshlaksky.
In the east is salt lake Kara-Bogaz-Gol, formerly a lagoon connected to the sea by a strait.
In 1980, a dam was built on it, through which water from the Caspian goes to Kara-Bogaz-Gol, where it then evaporates.

130 rivers flow into the Caspian Sea, located mainly in its northern part. The largest of them are: Volga, Terek, Sulak, Samur and Ural.
The average annual drainage of the Volga is 220 km³. 9 rivers have delta-shaped mouths.

Flora and fauna


The Caspian Sea is home to about 450 species of phytoplankton, including algae, aquatic and flowering plants. Of the 400 species of invertebrates, worms, crustaceans and molluscs predominate. There are a lot of small shrimp in the sea, which are the object of fishing.

More than 120 species of fish live in the Caspian Sea and delta. Fishing objects include sprat (“Kilkin fleet”), catfish, pike, bream, pike perch, kutum, mullet, roach, rudd, herring, white fish, pike perch, goby, grass carp, burbot, asp and pike perch. Stocks of sturgeon and salmon are currently depleted, however, the sea is the largest supplier of black caviar in the world.

Fishing in the Caspian Sea is allowed all year round, with the exception of the period from late April to late June. There are many fishing bases with all amenities on the coast. Fishing in the Caspian Sea is a great pleasure. In any part of it, including in large cities, the catch is unusually rich.


The lake is famous for its wide variety of waterfowl. Geese, ducks, loons, gulls, waders, eagles, geese, swans and many others fly to the Caspian Sea during the migration or nesting period.
The largest number of birds - over 600 thousand individuals - is observed at the mouths of the Volga and Ural, in the Turkmenbashi and Kyzylagach bays. During the hunting season, a huge number of fishermen come here not only from Russia, but also from countries near and far abroad.

Caspian seal


The Caspian Sea is home to the only mammal. This is the Caspian seal or seal. Until recently, seals swam close to the beaches, everyone could admire the amazing animal with round black eyes, and the seals behaved very friendly.
Now the seal is on the verge of extinction.

Cities on the Caspian Sea


The largest city on the Caspian Sea coast is Baku.
The number of one of the most the most beautiful cities the world is over 2.5 million people. Baku is located on the picturesque Absheron Peninsula and is surrounded on three sides by the waters of the warm and oil-rich Caspian Sea.
Less major cities: the capital of Dagestan is Makhachkala, the Kazakh Aktau, the Turkmen Turkmenbashi and the Iranian Bender-Anzeli.

Baku Bay, Baku - a city on the Caspian Sea

Interesting facts


Scientists are still debating whether to call a body of water a sea or a lake.
The level of the Caspian Sea is gradually decreasing.
The Volga delivers most of the water to the Caspian Sea.
90% of black caviar is mined in the Caspian Sea. Among them, the most expensive is the albino beluga caviar “Almas” ($2 thousand per 100 g).

Companies from 21 countries are taking part in the development of oil fields in the Caspian Sea. According to Russian estimates, hydrocarbon reserves in the sea amount to 12 billion tons.

American scientists claim that a fifth of the world's hydrocarbon reserves are concentrated in the depths of the Caspian Sea. This is more than the combined reserves of oil-producing countries such as Kuwait and Iraq.

The Caspian Sea is the most big lake on planet Earth. It is called the sea because of its size and bed, which is built like an ocean basin. The area is 371,000 square meters, the depth is 1025 m. The list of rivers flowing into the Caspian Sea includes 130 names. The largest of them are: Volga, Terek, Samur, Sulak, Ural and others.

Caspian Sea

It took 10 million years before the Caspian Sea was formed. The reason for its formation is that the Sarmatian Sea, having lost contact with the World Ocean, was divided into two bodies of water, which were called the Black and Caspian Seas. Between the latter and the World Ocean there are thousands of kilometers of waterless route. It is located at the junction of two continents - Asia and Europe. Its length in the north-south direction is 1200 km, west-east - 195-435 km. The Caspian Sea is an internal endorheic basin of Eurasia.

Near the Caspian Sea, the water level is below the level of the World Ocean, and it is also subject to fluctuations. According to scientists, this is due to many factors: anthropogenic, geological, climatic. Currently, the average water level reaches 28 m.

The river network and wastewater are unevenly distributed along the coast. A few rivers flow into part of the sea from the northern side: Volga, Terek, Ural. From the west - Samur, Sulak, Kura. East Coast characterized by the absence of permanent watercourses. Differences in space in the flow of water that rivers bring to the Caspian Sea are important geographical feature of this reservoir.

Volga

This river is one of the largest in Europe. In Russia it ranks sixth in size. In terms of catchment area it is second only to Siberian rivers flowing into the Caspian Sea, such as the Ob, Lena, Yenisei, and Irtysh. The source from which the Volga begins is taken to be a spring near the village of Volgoverkhovye, Tver Region, on the Valdai Hills. Now at the source there is a chapel that attracts the attention of tourists who are proud to step over the very beginning of the mighty Volga.

A small fast stream gradually gains strength and becomes a huge river. Its length is 3690 km. The source is 225 m above sea level. Among the rivers flowing into the Caspian Sea, the largest is the Volga. Its path runs through many regions of our country: Tver, Moscow, Nizhny Novgorod, Volgograd and others. The territories through which it flows are Tatarstan, Chuvashia, Kalmykia and Mari El. The Volga is home to millionaire cities - Nizhny Novgorod, Samara, Kazan, Volgograd.

Volga Delta

The main channel of the river is divided into channels. A certain shape of the mouth is formed. It's called delta. Its beginning is the place where the Buzan branch separates from the Volga river bed. The delta is located 46 km north of the city of Astrakhan. It includes channels, branches, and small rivers. There are several main branches, but only Akhtuba is navigable. Among all the rivers of Europe, the Volga has the largest delta, which is a rich fishing region in this basin.

It lies 28 m lower than ocean level. The mouth of the Volga is the location of the southernmost Volga city of Astrakhan, which in the distant past was the capital of the Tatar Khanate. Later, at the beginning of the 18th century (1717), Peter 1 gave the city the status of “capital of the Astrakhan province.” During his reign, the city's main attraction, the Assumption Cathedral, was built. Its Kremlin is made of white stone brought from the capital of the Golden Horde, the city of Saraya. The mouth is divided by branches, the largest of which are: Bolda, Bakhtemir, Buzan. Astrakhan is southern city located on 11 islands. Today it is a city of shipbuilders, sailors and fishermen.

The Volga currently needs protection. For this purpose, a reserve was established in the place where the river flows into the sea. Volga Delta, largest river, flowing into the Caspian Sea, is replete with unique flora and fauna: sturgeon fish, lotuses, pelicans, flamingos and others. Immediately after the revolution of 1917, a law was passed on their protection by the state as part of the Astrakhan Nature Reserve.

Sulak River

It is located in Dagestan and flows through its territory. It is fed by the waters of melted snow that flow from the mountains, as well as by tributaries: Maly Sulak, Chvakhun-bak, Akh-su. Water also enters Sulak through a canal from the Aksai and Aktash rivers.

The source is formed by the confluence of two rivers that originate in the basins: Didoiskaya and Tushinskaya. The length of the Sulak River is 144 km. Its pool has a fairly large area - 15,200 square meters. It flows through a canyon with the same name as a river, then through the Akhetlinsky gorge and finally reaches the plane. Rounding the Agrakhan Bay from the south, Sulak flows into the sea.

The river provides Kaspiysk and Makhachkala with drinking water; hydroelectric power stations, urban-type settlements Sulak and Dubki, as well as small town Kizilyurt.

Samur

The river received this name not by chance. The name translated from the Caucasian language (one of them) means “middle”. Indeed, the waterway along the Samur River marks the border between the states of Russia and Azerbaijan.

The sources of the river are glaciers and springs originating in the spurs of the Caucasus Range on the northeastern side, not far from Guton Mountain. The height above sea level is 3200 m. Samur has a length of 213 km. The height at the headwaters and the mouth differs by three kilometers. The drainage basin has an area of ​​almost five thousand square meters.

The places where the river flows are narrow gorges located between high mountains made of clayey shales and sandstones, which is why the water here is muddy. The Samur basin has 65 rivers. Their length reaches 10 km or more.

Samur: valley and its description

The valley of this river in Dagestan is the most densely populated area. Derbent is located near the mouth - ancient city peace. The banks of the Samur River are home to twenty or more species of relict flora. Endemic, endangered and rare species listed in the Red Book grow here.

In the river delta there is a relict forest, which is the only one in Russia. The liana forest is a fairy tale. Huge trees of the rarest and most common species grow here, intertwined with vines. The river is rich in valuable fish species: mullet, pike perch, pike, catfish and others.

Terek

The river received its name from the Karachay-Balkar peoples who lived along its banks. They called it “Terk Suu”, which means “swift water”. The Ingush and Chechens called it Lomeki - “mountain water”.

The beginning of the river is the territory of Georgia, the Zigla-Khokh glacier is a mountain located on the slope of the Caucasus ridge. It is located under glaciers all year round. One of them melts when sliding down. A small stream is formed, which is the source of the Terek. It is located at an altitude of 2713 m above sea level. The length of the river flowing into the Caspian Sea is 600 km. When it flows into the Caspian Sea, the Terek is divided into many branches, resulting in the formation of a vast delta, its area is 4000 square meters. In some places it is very swampy.

The riverbed in this place changed several times. The old branches have now been converted into canals. The middle of the last century (1957) was marked by the construction of the Kargaly hydroelectric complex. It is used to supply water to the canals.

How is the Terek replenished?

The river has a mixed supply, but for the upper reaches, water from melting glaciers plays an important role; they fill the river. In this regard, 70% of the flow occurs in spring and summer, that is, at this time the water level in the Terek is highest, and the lowest is in February. The river freezes if the winters are characterized by a harsh climate, but the ice cover is unstable.

The river is not clean and transparent. The water turbidity is high: 400-500 g/m3. Every year the Terek and its tributaries pollute the Caspian Sea, pouring into it from 9 to 26 million tons of various suspended matter. This is explained by the rocks that make up the shores, which are clayey.

Estuary Terek

The Sunzha is the largest tributary flowing into the Terek, the lower reaches of which are measured from this river. By this time, the Terek flows for a long time through the flat terrain, leaving the mountains located behind the Elkhotov gates. The bottom here is made of sand and pebbles, the current slows down, and in some places stops altogether.

The mouth of the Terek River has unusual look: the bed here is raised above the valley, along appearance resembles a canal, which is fenced with a high embankment. The water level becomes higher than the land level. This phenomenon is due to natural causes. Since the Terek is a turbulent river, it brings sand and stones from the Caucasus ridge to large quantities. Considering that the current in the lower reaches is weak, some of them settle here and do not reach the sea. For residents of this area, sediment is both a threat and a blessing. When they are washed away by water, floods of great destructive power occur, this is very bad. But in the absence of floods, the soils become fertile.

Ural River

In ancient times (until the second half of the 18th century) the river was called Yaik. It was renamed in the Russian way by decree of Catherine the Second in 1775. Just at this time, the Peasant War, the leader of which was Pugachev, was suppressed. The name has been preserved to this day in the Bashkir language, and is official in Kazakhstan. The Urals are the third longest in Europe; only the Volga and Danube are larger rivers.

The Urals originate in Russia, on the slope of the Round Hill of the Uraltau ridge. The source is a spring gushing out of the ground at an altitude of 637 m above sea level. At the beginning of its journey, the river flows in a north-south direction, but after encountering a plateau along the way, it makes a sharp turn and continues to flow in a north-west direction. However, beyond Orenburg its direction changes again to the southwest, which is considered the main one. Having overcome a winding path, the Urals flows into the Caspian Sea. The length of the river is 2428 km. The mouth is divided into branches and tends to become shallow.

The Ural is a river along which the natural water boundary between Europe and Asia passes, with the exception of the upper reaches. This is an inland European river, but its upper reaches east of the Ural Range are Asian territory.

The importance of the Caspian rivers

The rivers flowing into the Caspian Sea are of great importance. Their waters are used for human and animal consumption, domestic, agricultural and industrial needs. Hydroelectric power stations are built on rivers, the energy of which is in demand by people for various purposes. River basins are full of fish, algae, and shellfish. Even in ancient times, people chose river valleys for future settlements. And now cities and towns are being built on their banks. The rivers are plied by passenger and transport ships, performing important tasks for transporting passengers and cargo.