Goals and objectives of the lesson:
1.Introduce the natural complexes of the seas using the example of the White and Azov Seas.
2. Develop students’ cognitive interest and geographical thinking.
3.Improve skills in working with various sources of geographic
information.
4.Form a feeling of love for native nature.
Equipment:Physical card Russia, atlases, presentation “Sea of Azov”, film “Seas of Russia”.
During the classes
I. Organizational moment
II. Checking homework.
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Working with average students (Front survey)
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Working with weak students (Test)
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1. Choose the correct statements. A. Facies – large PTC. B. Zoning is a study of the nature of the Uporovo region IN. V.V. Dokuchaev created the science of PTC - landscape science. 2. The largest PC in terms of rank is: A. Mainland Eurasia. B. West Siberian Plain, IN. Geographical envelope. 3. Any human impact on nature A. They do not cause any consequences. B. Do not change the PC. IN. Change PC. 4.The science of natural territorial complexes is called: A. Zoning B. Facies IN. Landscape science Answers: 1B 2B 3B 4B
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III. Learning new material.
1) Teacher's story.
Natural complexes exist not only on land, but also in the ocean. L. S. Berg was the first to write about the existence of natural complexes of the bottom and surface of the sea. Underwater natural complexes are similar to the terrestrial complex in the unity and interaction of its constituent components: the underlying surface, water, flora and fauna.
Today our task is to use the example of the White and Azov Seas to show the specifics of the marine natural complex.
2) Working with a physical card.
Find in the Sea of Azov Kerch Strait, Sivash Bay, rivers flowing into the Sea of Azov: Don, Kuban.
Both seas are connected to the oceans by narrow straits, therefore they have a special appearance and are special natural complexes.
3) Presentation “Sea of Azov”.
4) Independent work of students.(Do it in a notebook)
Plan for studying (comparing) the PC of the seas.
Which ocean basin does it belong to?
Outlying or internal (connection with the ocean)
Area (compared to other seas)
Depths (predominant and greatest, conclusion: deep or shallow)
Salinity
Temperature (freezing or not)
Sea resources
Human activities aimed at preserving PC.
Why does the Azov Sea remain muddy for a long time after a storm? (It is shallow, depth - 5-7 m. Bottom silt also affects the excitement.)
Why is the salinity in Sivash 60%, although in Azov itself it is 11-13%0. (Very strong evaporation of heated waters, the bay is shallow and the influx of already salty water from Azov.)
V. Watching videos “Solovetsky Islands”, “Kandalaksha Nature Reserve”, “Bay (Lake) Sivash”
Homework.: § 22. Weak students - talk about the White Sea PC.
Individual assignments for average students
Prepare reports on natural areas of Russia:
Birds of the Arctic desert. - Diana
3) The wealth of the tundra. - Sasha Chiryatiev
Additional material
Sea of Azov
The Sea of Azov is almost a lake, a remnant of a more extensive system of straits that once connected the Black Sea with the Caspian Sea. The Sea of Azov is a record holder in its own way. This is one of the smallest seas in the world (only the Sea of Marmara is smaller) and the smallest sea washing the territory of Russia - its area (38,840 km2) is 11 times smaller than the Black Sea.
This is the shallowest sea in our country and the world: the greatest depth does not exceed 15 m, and the prevailing depths are 5-7 m. It can be compared to a flat-bottomed saucer. Therefore, during storms, waves cover the entire thickness of the water and bottom silt, after which the sea remains cloudy for a long time.
Sea of Azov (in ancient times it was called the Sea of Surozh) - “Mediterranean” - internal in the basin Atlantic Ocean. The Kerch Strait connects it with the Black Sea. The largest bay (Taganrog) protrudes deep into the land in the northeastern part of the sea. Off the western and northern shores there is a system of small bays, collectively called Sivash. Sivash is separated from the sea by the narrow Arabat Spit.
The Don and Kuban are major rivers that flow into the Sea of Azov. River waters significantly desalinate sea water at their confluence - up to 5-6%o with an average sea salinity of 11 - 130/00.
Decrease river flow due to the construction of reservoirs and the consumption of Don and Kuban waters for irrigation, it led to an increase in the salinity of the Azov Sea. This turned out to be disastrous for part of the plankton on which the fish feed, and for the juveniles of many valuable fish (pike perch, bream, sturgeon, stellate sturgeon). The amount of fish in the sea has decreased, although its commercial value is still great.
In summer, sea water temperature is +25-30 3C, in winter below 0 °C. From the end of December to the end of February - beginning of March, the sea is covered with ice.
The northern shores of the Sea of Azov have excellent natural conditions for sea and climatic resorts.
Sivash can only formally, due to the presence of a strait at the Arabat Spit, be considered a gulf of the Sea of Azov. This body of water is so isolated and has such a unique appearance and regime that some oceanographers call it a sea, despite its amazing shallowness (about 1 m) and small size (2560 km 2). The second name of Sivash also sounds reasonable - Rotten Sea (from the smell of algae decomposing in it).
Sivash is a natural reservoir of salts. Over the summer, it evaporates up to half the volume of its water. In addition to rare rains, they are replenished only by a trickle of Azov water entering through the strait. With this water, salts also enter Sivash. Evaporation in shallow water is so intense that even in the strait, the brackish Azov water turns into bitter-salty water, reaching 60%o, and in Sivash itself it contains up to 170 mg of salts per 1 kg of water, t . i.e. 5 times more than the average in the World Ocean.
To restore and increase the marine resources of the Azov Sea, there is a fish farm in the coastal zone of the Taganrog Bay.
With the participation of geographers, projects for resort and health complexes are being created on the Sea of Azov, the shores of which have not yet been sufficiently developed.
TEST
Introduction
Vast spaces of Russia are washed by a number of different natural conditions seas located mainly on the periphery of Russian territory. Together with natural features Economic activities in marine and coastal areas shape the ecological state of the sea, that is, environmental conditions that are real in time and space. They are not constant in time and space, which causes variability in the ecological state of the sea.
The topic of my thesis is the ecological state of the seas of Russia. Recent decades have been marked by increased anthropogenic impacts on marine ecosystems as a result of pollution of the seas and oceans. The distribution of many pollutants has become local, regional and even global scale. Therefore, pollution of the seas and their biota has become the most important problem countries, and the need to protect the marine environment from pollution is dictated by the requirements rational use natural resources. No one will dispute the advisability of protecting the seas and the life developed in it from the harm that waste emissions can cause. Because of this, the chosen topic of work is currently very relevant.
The purpose of the work is comprehensive characterization ecological state of Russian sea waters. The main objectives are:
1) Consideration of the seas of Russia as large natural complexes, highlighting their main properties;
2) Determination of the main substances polluting sea waters and the sources of their entry into the sea;
3) Analysis of the current ecological state of the seas of Russia (the basins of the Atlantic, Arctic and Pacific oceans, as well as the Caspian sea-lake);
4) Assessment of the environmental consequences of sea water pollution, clarification of the main protection measures and methods of controlling sea pollution.
The structure of the thesis corresponds to the assigned tasks. The material is presented in three main chapters.
The first chapter gives an idea of the seas washing the shores of Russia as large natural complexes.
The second chapter reflects an analysis of the current ecological state of the seas of Russia (as well as a description of the main pollutants and sources of their entry into sea waters).
The third chapter is devoted environmental consequences sea pollution, as well as the problem of protecting the seas from pollution.
In preparing the thesis, various sources of information were used - literature, periodicals, statistical data, cartographic materials, resources of the global Internet information network (there are links in the text).
The seas of Russia as large natural complexes
The territory of our country is washed by thirteen seas: 12 seas of the world ocean and the Caspian Sea, which belongs to the internal closed basin (Fig. 1). These seas are very diverse both in natural conditions and in natural resources, and according to the degree of their knowledge and mastery.
Figure 1. Seas of Russia
The total area of Russia's territorial waters and exclusive economic zone is about 7 million square kilometers.
Area of continental shelf under jurisdiction Russian Federation- about 5 million square kilometers, which is about 1/5 of the shelf area of the World Ocean.
The Far Eastern Marine Reserve is the only reserve in Russia, founded in 1978. as exclusively marine. In addition to it, marine nature is protected in 8 more reserves and 2 sanctuaries Far East, 2 Arctic reserves, 2 reserves and 1 reserve in the Barents and White Seas and 2 reserves in the Caspian Sea (see Appendix 1).
The seas of Russia have a number unique features:
· The Barents, Bering and Okhotsk seas are among the most productive seas in the world, and the productivity of the West Kamchatka shelf is the highest in the world and amounts to about 20 t/km².
· In the Far Eastern seas of Russia, stocks of commercial species with global significance: pollock, Pacific salmon, Kamchatka crab.
· Significantly larger cod stocks (compared to the North Atlantic) remain in Arctic and Pacific waters.
· Russian seas have the highest diversity of sturgeon and salmon fish in the world.
· The most important migration routes of marine mammals and birds of the northern hemisphere pass along the coast of the Russian seas.
· Unique ecosystems have been discovered in the Russian seas: the relict ecosystem of Lake Mogilnoye, relict ecosystems of kelps in the Arctic (Chaunskaya Bay), shallow hydrothermal communities in the bays of the Kuril Islands.
The seas of the Arctic Ocean are located within the continental shallows (shelf). Their depth rarely exceeds 200 m, and their salinity is lower than oceanic. The coastline is very indented. The climate of almost all northern seas is very harsh, with the only exception being the Barents Sea, which receives the waters of the warm North Atlantic Current.
Most seas are covered with ice for 8-10 months.
The Northern Sea Route, an important transport route for Russia, passes through the seas of the Arctic Ocean. This is the shortest route from St. Petersburg to Vladivostok.
The Barents Sea is a marginal water area of the Arctic Ocean on the border with the Atlantic Ocean, between the northern coast of Europe in the south and the Vaigach Islands, New Earth, Franz Josef Land in the east, Spitsbergen and Bear Island in the west (Fig. 2). The sea area is 1424 thousand km², depth is up to 600 m. The sea is located on the continental shelf. The southwestern part of the sea does not freeze in winter due to the influence of the North Atlantic Current. The southeastern part of the sea is called the Pechora Sea.
Figure 2. Barents Sea
In the West it borders on the Norwegian Sea basin, in the South - on the White Sea, in the East - on the Kara Sea, in the North - on the North Sea. Arctic Ocean. Area Barents Sea, located east of Kolguev Island, is called the Pechora Sea. The shores of the Barents Sea are predominantly fjord, high, rocky, and heavily indented.
The salinity of the surface layer of water in the open sea throughout the year is 34.7-35.0 ppm in the southwest, 33.0-34.0 in the east, and 32.0-33.0 in the north. In the coastal strip of the sea in spring and summer, salinity drops to 30-32, and by the end of winter it increases to 34.0-34.5.
The climate of the Barents Sea is influenced by the warm Atlantic Ocean and the cold Arctic Ocean. Frequent intrusions of warm Atlantic cyclones and cold Arctic air determine greater variability weather conditions. In winter, southwestern winds prevail over the sea, and in spring and summer, northeastern winds. Storms are frequent. average temperature air in February varies from?25°C in the north to?4°C in the southwest. The average temperature in August is 0°C, 1°C in the north, 10°C in the southwest. Cloudy weather prevails over the sea throughout the year.
Arrival of warm Atlantic waters determines the relatively high temperature and salinity in the southwestern part of the sea. Here in February - March the water temperature on the surface is 3°C, 5°C, in August it rises to 7°C, 9°C. North of 74° N. w. and in the southeastern part of the sea in winter the water temperature on the surface is below? 1°C, and in the summer in the north 4°C, 0°C, in the southeast 4°C, 7°C. In summer, in the coastal zone, the surface layer of warm water 5-8 meters thick can warm up to 11-12°C.
The Barents Sea is rich various types fish, plant and animal plankton and benthos. Seaweed is common along the southern coast. Of the 114 species of fish living in the Barents Sea, 20 species are the most commercially important: cod, haddock, herring, sea bass, catfish, flounder, halibut, etc. Among the mammals found: polar bear, ringed seal, harp seal, beluga whale, etc. There is a seal fishery. Bird colonies abound on the coasts (guillemots, guillemots, kittiwake gulls). In the 20th century, the Kamchatka crab was introduced, which was able to adapt to new conditions and begin to reproduce intensively.
Seas Pacific Ocean wash the eastern shores of Russia from Chukotka to Vladivostok. They are separated from the ocean by archipelagos of islands, but freely communicate with it through numerous straits.
These seas are distinguished by significant depth - from 2500 to 4000m.
The Bering Sea is a sea in the north of the Pacific Ocean, separated from it by the Aleutian and Commander Islands; The Bering Strait connects it to the Chukchi Sea and the Arctic Ocean. The Bering Sea washes the shores of Russia and the USA. In winter it is covered with ice.
Area 2.304 million km². The average depth is 1600m, the maximum is 4773m. The air temperature over the water area is up to +7, +10°C in summer and -1, -23°C in winter. Salinity 33-34.7 ppm.
The Sea of Okhotsk is part of the Pacific Ocean, separated from it by the Kamchatka Peninsula, Kuril Islands and the island of Hokkaido (Fig. 3). The sea washes the shores of Russia and Japan.
Figure 3. Sea of Okhotsk
Area 1.603 million km². Average depth 1780m maximum depth 3521m. The western part of the sea has shallow depth and is located on the continental shelf. In the eastern part there is the Kuril Basin, where the depth is maximum.
From October to May-June, the northern part of the sea is covered with ice. The southeastern part practically does not freeze.
The coast in the north is strongly indented; in the northeast of the Sea of Okhotsk its largest bay is located - Shelikhov Bay.
The Sea of Japan is a sea within the Pacific Ocean, separated from it by the Japanese Islands and Sakhalin Island. It washes the shores of Russia, Korea, Japan, and the DPRK. In Korea, the Sea of Japan is called " East Sea" A branch comes to the south warm current Kuroshio.
Area 1.062 million km². The greatest depth is 3742m. Northern part The sea freezes in winter.
The Atlantic Ocean basin includes the Baltic, Black and Azov seas, connected to the ocean through neighboring seas and narrow straits.
The Black Sea is an inland sea of the Atlantic Ocean. The Bosphorus Strait connects with the Sea of Marmara, then, through the Dardanelles Strait, with the Aegean and Mediterranean Seas (Fig. 4). The Kerch Strait connects with the Sea of Azov. From the north, the Crimean Peninsula cuts deep into the sea. The water border between Europe and Asia Minor runs along the surface of the Black Sea.
Figure 4. Black and Azov Seas
Area 422,000 km² (according to other sources - 436,400 km²). The outline of the Black Sea resembles an oval with the longest axis about 1150 km. The greatest length of the sea from north to south is 580 km. The greatest depth is 2210m, the average is 1240m.
The sea washes the shores of Russia, Ukraine, Romania, Bulgaria, Turkey and Georgia. On the northeastern coast of the Black Sea there is an unrecognized public education Abkhazia.
A characteristic feature of the Black Sea is the complete (with the exception of a number of anaerobic bacteria) absence of life at depths above 150-200 m due to the saturation of the deep layers of water with hydrogen sulfide.
The Sea of Azov is the northeastern side basin of the Black Sea, with which it is connected by the Kerch Strait (Fig. 4). This is the shallowest sea in the world, its depth does not exceed 15 meters.
Its greatest length is 343 km, its greatest width is 231 km; coastline length 1472 km; surface area - 37605 km². (this area does not include islands and spits, which occupy 107.9 sq. km).
According to its morphological characteristics, it belongs to the flat seas and is a shallow body of water with low coastal slopes. In terms of distance from the ocean to the mainland, the Sea of Azov is the most continental sea on the planet.
In terms of biological productivity, the Sea of Azov ranks first in the world. The most developed are phytoplankton and benthos. The hydrochemical features of the Sea of Azov are formed primarily under the influence of the abundant influx river waters(up to 12% of water volume) and difficult water exchange with the Black Sea.
The salinity of the sea before the regulation of the Don was three times less than the average salinity of the ocean. After the creation of the Tsimlyansky hydroelectric complex, the salinity of the sea began to increase (up to 13 ppm in the central part). Average seasonal fluctuations in salinity values rarely reach 1%.
During the 20th century, almost all more or less large rivers flowing into the Sea of Azov were blocked by dams to create reservoirs. This has led to a significant reduction in discharge fresh water and mud in the sea.
The Baltic Sea (from antiquity until the 18th century in Russia was known as the “Varangian Sea”) is an inland marginal sea that protrudes deeply into the mainland (Fig. 5). The Baltic Sea is located in northern Europe, belongs to the Atlantic Ocean basin.
Figure 5. Baltic Sea
Area: 415 thousand km². Depth: average - 52m, maximum - 459m. The Baltic Sea is rich in seafood, in addition, there are oil reserves, in particular, the D-6 field is being developed (territorial waters of the Kaliningrad region of the Russian Federation)
The Caspian Sea is the largest lake on Earth, located at the junction of Europe and Asia and called a sea because of its size. The Caspian Sea is an endorheic lake, and the water in it is salty, from 0.05 ‰ near the mouth of the Volga to 11-13 ‰ in the southeast. The water level is subject to fluctuations, currently approximately 28 m below the level of the World Ocean. The area of the Caspian Sea at present is approximately 371,000 km², the maximum depth is 1025 m (Fig. 6).
Figure 6. Caspian Sea
The seas of Russia are of great economic importance. First of all, these are cheap transport routes, the role of which is especially important in foreign trade transport. Of significant value biological resources seas. The seas washing the territory of our country are home to almost 900 species of fish, of which more than 250 are commercial, and many marine mammals, mollusks and crustaceans. The importance of the mineral resources of the seas is increasing. You can use the energy of sea tides to generate electricity; in addition, the sea coasts are vacation spots.
IN Lately, as a result of the ever-increasing influence economic activity human impact on the World Ocean has sharply worsened ecological situation seas. To preserve the natural complexes of the seas, a special state program is needed.
The Sea of Azov belongs to the Atlantic Ocean and is connected to the Black Strait through the Kerch Strait
by sea. The Sea of Azov is the shallowest in the world, its maximum depth is 14 meters, the average depth is about 7.5 m. The area is 37,000 km². The sea has many bays and estuaries. The largest bays:
Taganrog, Temryuk, Kazantip, Arabat, Obitochny, Berdyansk. In the west, the Arabat Spit separates the Sivash Bay (Rotten Sea) from the sea; its shores are covered with a layer of salt in summer.
The gently sloping and low bank is strewn with shell rock. The spits are formed only on the northern coast, this is the result of long work sea waves, which washed shell rock along the shore. In the north, sea spits lined up: Biryuchiy Island, Obitochnaya, Berdyanskaya, Belosarayskaya, Krivaya, Tuzlinskaya. A large number of braids - characteristic feature shores of the Azov Sea.
Temperature The Sea of Azov is characterized by great seasonal variability. Minimum temperature observed in winter (January–February), the water cools to +3 ... –3 0С. Starting in December, the Sea of Azov freezes. In summer +24…+26°С.
The main current is a circular current along the shores of the Sea of Azov in a counterclockwise direction. average speed current movement is 10–20 cm/s.
The salinity of the sea is three times less than the average salinity in the ocean, and is 12 ‰. The maximum water salinity is observed in Sivash Bay – 250 ‰. Minimum salinity indicators in the north of the sea, in the Taganrog Bay. The salinity indicator is constantly changing due to a decrease in the flow of fresh water from rivers. In the sea
The rivers Don, Kuban, Mius, Kalmius, Berda, and Obitochnaya carry their waters.
By biological productivity The Sea of Azov occupies first place in world. The diversity and richness of life in the Sea of Azov is explained by the content of organic substances, which is 5-6 times higher than in other bodies of water. Rivers supply the sea with a mass of inorganic and organic substances that are washed out of the soil.
Inorganic substances necessary for development flora, organic - for the animal.
Among the inhabitants of the Sea of Azov there are many ancient ones that have already become extinct in other seas. Among them
include two types of mollusks, one type of crustacean and annelids. 115 species of fish have been registered in the Sea of Azov. In addition to sea sturgeon, bream, pike perch, ram, sabrefish, mullet, herring, anchovy, flounder, and goby, there are also freshwater fish: crucian carp, gudgeon, roach, tench, and pike. Tuna, mackerel, and eel swim here from the Mediterranean and Black Sea, making constant migrations. Among the marine mammals, the Azov white-sided dolphin, harbor porpoise are found here, and the Black Sea dolphin swims.
Azov water has healing properties . The shallow depth promotes good water heating. The combination of sea air and water, sun, beaches with golden sand makes it possible to develop
recreational resources. On the territory of the Donetsk region settlements: Melekino, Yalta, Urzuf, Novoazovsk, Sedovo are recognized as resorts.
The Sea of Azov is important transport route. The main port of the Donetsk region is Mariupol.
Problems:
During the twentieth century, almost all rivers flowing into the Sea of Azov were blocked by dams to create reservoirs. This has led to a significant reduction in discharge fresh water and silt in the sea. After
creation of a hydroelectric complex on the Don, The salinity of the sea began to increase. Due to this spawning conditions have worsened fish
Main sources of pollution are industrial enterprises.
The transparency of the waters of the Azov Sea is low. In summer, due to rapid development in upper layers The water of the smallest plant and animal organisms takes on a bright green color. This phenomenon is called " bloom" of the sea.
Lesson summary on geography 8th grade
Subject: Natural complex of the Azov Sea. Practical work: “Drawing up a navigational route for the Sea of Azov.”
Target:
Educational: to form primary knowledge about the Sea of Azov; consider water world;
Developing: develop the ability and skills to work with a map in the Donetsk region.
Educational: fostering the importance of studying geography, curiosity, local history approach.
Equipment: Physical map of the Donetsk region, contour maps, atlases, handouts.
Lesson type: lesson in mastering knowledge and skills.
During the classes
1. Organizational moment.
2. Checking homework.
Give answers to the questions:
Determine what factors determine the landscape structure of the Donetsk steppe?
Explain why within one steppe natural area Are different landscapes united?
What types of economic activities are favored by the nature of the steppe?
Think about it, if all kinds of economic activity stopped in our region, would the steppe be restored?
3. Communicating the topic, the purpose of the lesson objectives and the motivation for learning activities.
The aquatic natural complex of our region is the Sea of Azov. The sea is a natural complex in which, as in land complexes, all components are closely interconnected and interdependent.
4. Learning new knowledge.
The Sea of Azov belongs to the Atlantic Ocean and is connected to the Black Sea through the Kerch Strait. The Sea of Azov is the shallowest in the world, its maximum depth is 14 meters, the average depth is about 7.5 m. The area of the Sea of Azov is 37,000 km². Its greatest length is 343 km, its greatest width is 231 km. The length of the coastline is 2686 km, of which more than 100 km are in the Donetsk region.
The sea has many bays and estuaries. The largest bays:
Taganrog, Temryuk, Kazantip, Arabat, Obitochny, Berdyansk. In the west, the Arabat Spit separates the Sivash Bay (Rotten Sea) from the sea; its shores are covered with a layer of salt in summer.
In origin, the Azov Sea basin is a neotectonic depression on the border of the East European Platform and the Mediterranean Mobile Belt. Therefore, the topography of the bottom of the sea and its bays is monotonous: the slope, steep enough for the coast, turns into a smooth flat bottom, in the center of which the greatest depths are observed. The basin resembles a saucer with a smooth and flat bottom. The gently sloping and low bank is strewn with shell rock. The shores are flat, only in the southern part of the Kerch and Taman peninsulas they are raised and separated by a strait.
Rice. 1. Sea of Azov
The smooth curves of the sea coastline, indented by long sand spits, create the uniqueness of the Azov coast. In the north there are sea spits lined up: Biryuchiy Island, Obitochnaya, Berdyanskaya, Belosarayskaya, Krivaya, Tuzlinskaya. A large number of spits is a characteristic feature of the shores of the Azov Sea. The spits are formed only on the northern coast; this is the result of the prolonged work of sea waves that washed shell rock along the shore. Such sediment accumulates where the shore protrudes significantly into the sea
compared to neighboring shores.
The steppes come close to the sea, and in some placesreed floodplains.
The climatic conditions of the Azov Sea have continental features. The temperature regime of the Azov Sea is characterized by great seasonal variability. The minimum temperature is observed in winter (January–February), the water cools to +3 ... –3 0 C. Starting in December, the Sea of Azov freezes. At the end of February the ice melts. Only in the southern part of the sea near the Kerch Strait is the surface water temperature positive. The southern part of the sea does not freeze. In summer, a fairly uniform surface temperature is established almost throughout the entire sea, +24...+26°C. Her maximum values observed in the surface layer of water: in July +28.0…+28.5°С.
Sea currents depend on the strong north-eastern and south-western winds blowing here and therefore change direction very often. The main current is a circular current along the shores of the Sea of Azov in a counterclockwise direction. The average speed of currents is 10–20 cm/s.
The hydrochemical features of the Sea of Azov are formed under the influence of the influx of river water (up to 12% of the water volume) and difficult water exchange with the Black Sea. The salinity of the sea is three times less than the average salinity in the ocean, and is 12‰ . The maximum water salinity is observed in Sivash Bay - 250‰ . Minimum salinity indicators in the north of the sea, in the Taganrog Bay. The salinity indicator is constantly changing due to a decrease in the flow of fresh water from rivers. The rivers Don, Kuban, Mius, Kalmius, Berda, and Obitochnaya carry their waters to the sea.
The salinity of the sea before the regulation of the Don ranged from 1‰ at the mouth of the Don up to 10.5‰ in the central part of the sea and 11.5 ppm near Kerch
Strait.
During the twentieth century, almost all rivers flowing into the Sea of Azov were blocked by dams to create reservoirs. This has led to a significant reduction in the discharge of fresh water and silt into the sea. After the creation of a hydroelectric complex on the Don, the salinity of the sea began to increase.
The transparency of the waters of the Azov Sea is low. The color of the water here varies from greenish-yellow to brownish-yellow. In summer, due to the rapid development of the smallest plant and animal organisms in the upper layers of water, the water acquires a bright green color. This phenomenon is called sea bloom.
The soils of the sea are soft, loose, and are constantly transported by currents, which causes rapid siltation of shipping channels and port waters. There are mud volcanoes at the bottom of the sea.
In terms of biological productivity, the Sea of Azov ranks first in the world.
The diversity and richness of life in the Sea of Azov is explained by the content of organic substances, which is 5-6 times higher than in other bodies of water. Rivers supply the sea with a mass of inorganic and organic substances that are washed out of the soil. Inorganic substances are necessary for the development of the plant world, organic substances are necessary for the animal world.
The desalinated, well-warmed and fertilized waters of the Sea of Azov provide an environment for the development of phytoplankton and zooplankton. There are 150 species of planktonic algae alone in the sea. In summer, masses of these algae make the water thick and affect the color of the water. During the flowering period in water at 1 m 3 phytoplankton weighs up to 2 kg. The number and variety of small animals swimming in the water column varies depending on the seasons. Among the zooplankton there is an exclusively Azov species of jellyfish, not found anywhere else.
Among the inhabitants of the Sea of Azov there are many ancient ones that have already become extinct in other seas. These include two types of mollusks, one type of crustacean and annelids. A great variety of worms, mollusks, and crustaceans live at the bottom; their productivity is very high and amounts to 19 million tons per year. They serve as food for fish.
In terms of the number of fish per unit area, the Azov Sea is 6.5 times greater than the Caspian Sea, 40 times greater than the Black Sea and 160 times greater than the Mediterranean Sea.
115 species of fish have been registered in the Sea of Azov. In terms of fish diversity, it surpasses the Black Sea. In addition to sea sturgeon, bream, pike perch, ram, sabrefish, mullet, herring, anchovy, flounder, and goby, there are also freshwater fish: crucian carp, gudgeon, roach, tench, and pike. Freshwater species usually live permanently in one area of a body of water and do not make large migrations. Tuna, mackerel, and eel swim here from the Mediterranean and Black Sea, making constant migrations.
Among the marine mammals, the Azov white-sided dolphin, harbor porpoise are found here, and the Black Sea dolphin swims.
Azov water has healing properties. The shallow depth promotes good water heating. The combination of sea air and water, sun, beaches with golden sand makes it possible to develop recreational resources.On the territory of the Donetsk region, the settlements: Melekino, Yalta, Urzuf, Novoazovsk, Sedovo are recognized as resorts.
The Sea of Azov is an important transport route. The main port of the Donetsk region is Mariupol.
In the middle of the twentieth century, due to human activity, the natural complex of the Azov Sea began to change. As a result of river regulation, the use of river waters for economic activities, and the construction of reservoirs, the flow of fresh water decreased, and more salty Black Sea water began to flow through the Kerch Strait. As a result, fish spawning conditions have worsened.
IN last years The ecological situation in the Sea of Azov has worsened. The main sources of pollution are industrial enterprises.
4. consolidation of the studied material.
Exercise 1.
Give answers to the questions.
Compare the natural-territorial complex and the natural-aquatic complex.
Describe the hydrological regime of the Sea of Azov.
Determine the consequences of increasing salinity in the waters of the Sea of Azov.
Explain the reasons for the high biological productivity of the Azov Sea.
Task 2.
Practical work No. 9 “Drawing up a navigational route for the Sea of Azov” On contour map in the waters of the Sea of Azov, designate:
coastline elements;
rivers that flow into the sea;
hydrological regime of the sea;