The largest lake in Africa

The largest rivers and lakes in Africa are our topic today. Most big river Africa is the Nile (length 6500 km). It originates in the mountains of East Africa and flows through Lake Victoria. In this case, a series of waterfalls are formed in the upper reaches. Coming out onto the plain, the Nile flows slowly through vast swamps and breaks into separate branches.

Whole floating islands are formed from densely intertwined swamp plants, which, moving along the river, clutter its bed and impede navigation.

Here the river is called the White Nile. It connects with the Blue Nile, flowing from the Abyssinian Highlands. After this confluence, the river makes large bends, many rapids are formed, along which its waters quickly rush through granite rocks. Navigation here is possible only in certain areas.

In its lower reaches, the Nile passes through deserts, receiving no tributaries at all and losing a lot of water from strong evaporation. The river flows into the Mediterranean Sea and forms a large delta.

Due to tropical rainfall in the upper reaches, especially in the Abyssinian Highlands, the Nile rises in summer and carries a mass of muddy water, gradually spreading downwards.

Therefore, the Nile in its lower reaches (in Egypt), despite the prevailing heat and complete absence of rain, floods widely at the end of summer and beginning of autumn. It provides water for irrigating fields and leaves fertile silt on them after the spill. Egypt, a country of ancient agriculture, lying among deserts, is entirely a “gift of the Nile.”

The largest rivers and lakes in Africa. The second largest major river in Africa is the Congo, it flows through the humid equatorial region and is characterized by extreme high water levels. There are a lot of waterfalls and rapids on the river, so only certain sections of it are navigable.

The deep-flowing Niger flows into the Gulf of Guinea. It begins in the mountains near the shores of the Atlantic Ocean and first heads into the interior of Africa, but then turns back to the ocean. The Niger also has many rapids and waterfalls, and forms a delta at its mouth.

The Zambezi is the largest river flowing into the Indian Ocean. It is home to the large Victoria Falls. The water here falls with a strong roar from a height of 120 m into a narrow crevice crossing the river bed. The roar and roar of water can be heard for tens of kilometers around.

Above the waterfall, huge columns of spray and water dust rush upward for hundreds of meters. Reflecting in them, the sun's rays give rise to multi-colored rainbows that flash, go out and light up again, shimmering with wonderful colors.

The largest rivers and lakes in Africa. The largest and deepest lakes are located in eastern Africa. They occupy depressions in the East African fault zone.

Sub-Saharan Africa in the middle of Africa is the drainless but freshwater Lake Chad. It is shallow, often changes the outline of the banks, becoming smaller and larger in size - this depends on the frequency and intensity of rains and the flood of the rivers flowing into it.

African inland waters

Ground and underground waters

Groundwater and groundwater are of great importance for deserts and semi-deserts. Groundwater has a mainly linear distribution in the form of sub-channel flows of episodic rivers. Large artesian basins are especially important in the Sahara and in the arid regions of South Africa. In the Sahara, fresh or slightly saline groundwater is confined mainly to Lower Cretaceous continental sandstones. In the semi-deserts and deserts of South Africa, groundwater accumulates mostly in bedrock cracks, karst limestones and, presumably, sandstones of the Karoo system. Where groundwater comes to the surface, oases are formed. Date palms grow in the oases, various fruit trees, tropical crops are grown. U artesian wells watering places for livestock are arranged. Searching, mining and rational use groundwater is one of the vital important issues African states located in the dry regions of the continent. Hydrogeologists from Russia are helping in the search for groundwater in the deserts of North Africa.

Rivers of Africa

In terms of the total volume of annual runoff (4600 km3), Africa ranks third after Eurasia and South America, and in terms of layer thickness (less than 160 mm) it is inferior to all continents except Australia and Antarctica. The main watershed of the African continent runs along its most elevated eastern edge, so more than 1/3 of the surface drains into the Atlantic Ocean, only about 1/4 into the Indian Ocean, and even less into the Mediterranean Sea. About 1/3 of Africa's surface (approximately 9 million km2) has no flow into the ocean and belongs to inland basins or has no surface flow at all. Surface waters are distributed extremely unevenly across the continent, and both the distribution and the regime of flowing waters are closely dependent on the amount and regime of rainfall in a particular part of the continent. Snow and glacier feeding plays an insignificant role in Africa. In the equatorial regions, rivers have a uniform flow throughout the year, without pronounced minimums, but with two periods of maximums due to rains. Areas with a subequatorial climate (Sudan, the southern part of the Congo Basin and others) are characterized by a pronounced summer maximum runoff and a corresponding increase in river flow. On the northwestern and southwestern edges of the continent, rivers have a clearly defined winter maximum associated with winter cyclonic rains in each hemisphere.

Between the areas with summer and winter maximum flows there are vast areas that are generally devoid of constant flow. These are the Sahara in the northern and a significant part of the Kalahari in the southern hemisphere, which are practically devoid of watercourses; they are crossed by a network of dry riverbeds that fill with water only for a short time after rare occasional rains. A developed network of dry riverbeds and an abundance of dry depressions, only periodically filled with water and characteristic of the now arid regions of Africa, indicate the existence previously of more humid areas within its borders. climatic conditions. The last pluvial period corresponded to the period of the last glaciation in the high latitudes of the northern hemisphere. All of Africa's most significant rivers irrigate vast basins separated from the oceans by plateaus and mountain ranges. The uplifts caused a revival of erosion activity and contributed to the formation of large rapids and waterfalls in the valleys of many rivers. They impede navigation and greatly reduce transport value African rivers, but at the same time contain huge hydropower resources, the use of which has been expanding in recent decades in a number of African states

North Africa

North Africa

Nile - Egypt, Sudan
White Nile - Sudan
Upper Nile - Uganda
Atbara - Sudan, Ethiopia
Tekaze - Sudan, Ethiopia
Blue Nile - Sudan, Ethiopia

West Africa

Bandama - Ivory Coast
Cavalli - Liberia, Ivory Coast
Gambia - Gambia, Senegal
Niger - Nigeria, Benin, Niger, Mali
Veme - Benin
Saint Paul - Liberia
Sanaga - Cameroon
Senegal - Senegal, Mauritania, Mali
Volta - Ghana, Burkina Faso
Black Volta - Burkina Faso
White Volta - Burkina Faso
Red Volta - Burkina Faso

East Africa

Juba - Ethiopia, Somalia
Dawa - Ethiopia
Gabele - Ethiopia
Wabe Shabelle - Ethiopia, Somalia
Kerio - Kenya
Maputo - Mozambique
Mara - Kenya, Tanzania
Rufiji - Tanzania
Ruvuma - Tanzania, Mozambique
Tana - Kenya

Central Africa

Congo
Kwango
Kassai
Lualaba
Crowbars
Ubangi - Democratic Republic of the Congo, Republic of the Congo, Central African Republic
Uele
Mbomou
Gabon
Kwilu in the upper reaches - Niari - Congo
Mbini
Ntem
Nianga - Gabon
Ogooue - Gabon

South Africa

Breede - South Africa
Kwanzaa - Angola
Fishriver - Namibia
Groot - South Africa
Kuiseb - Namibia
Kunene - Angola - Namibia, Botswana
Kwando - Namibia (downstream of Linyanti)
Limpopo - Mozambique, South Africa, Zimbabwe, Botswana
Molopo - Botswana, South Africa
Okavango - Botswana, Namibia, Angola
Orange - South Africa, Lesotho, Namibia
Tugela - South Africa
Vaal - South Africa
Zambezi - Angola, Zambia, Namibia, Zimbabwe, Mozambique
Shire - Malawi, Mozambique

The longest river in Africa - the Nile (6671 km) - is the longest river on the ground. The area of ​​the Nile basin is 2870 thousand km2. The average water flow near Aswan is 2600 m3/s. By features natural conditions basin, the nature of the hydrographic regime and the significance that the Nile has in the life of the peoples living in its valley, it is one of the most unique and remarkable rivers in the world. The source of the Nile is considered to be the Kagera River, which originates at an altitude of more than 2000 m on one of the massifs of East Africa, south of the equator, and flows into Lake Victoria. A river called the Victoria Nile emerges from the lake. It flows through Lake Kyoga and empties into Lake Albert, below which it is called Albert Nile. Throughout this entire section of the river, the river has a mountainous character, is very rapid and forms several waterfalls. The largest waterfall is Kabalega (Murchison) on the river. Victoria Nile - reaches 40 m in height. Leaving the highlands under the Arabic name Bahr El Jabal, which means “river of the mountains,” the river enters a vast and flat basin. Its flow slows down, and the channel breaks up into branches. The largest tributaries in this part of the stream are El Ghazal (“river of gazelles”) and Sobat. Flowing from the mountains, Sobat carries muddy yellow water containing a large number of suspended material. Below Sobat the river is called the White Nile (Bahr el-Abyad). Near the Sudanese city of Khartoum, the White Nile merges with the Blue Nile (Bahr el-Azraq) and here it receives the name Nile. The Blue Nile originates in the Ethiopian Highlands, flowing from Lake Tana. From the same highlands the Nile receives its last large tributary, the Atbaru. Below its confluence, the Nile cuts through a plateau composed of hard sandstones and crosses a series of rapids (cataracts). There are a total of six rapids between Khartoum and Aswan. Below Aswan, the Nile flows in a valley 20-50 km wide, which at the beginning of the Anthropocene was a bay of the Mediterranean Sea. The Nile Valley ends with a delta formed on the site of a bay, which was gradually filled with sediment from the river. The delta area is 24 thousand km2.

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Neil - the only river North Africa, which crosses the Sahara and brings its waters to the Mediterranean Sea, being the source of life in the arid desert. The permanent flow of the Nile exists due to the precipitation that falls in more southern regions and feed its origins. White Nile, starting at equatorial belt, receives nutrition from the rains that fall throughout the year. In the upper reaches, the water level in the river is very high and fairly constant, as it is regulated by lakes. But within the Upper Nile Basin, a large amount of water is lost to evaporation, and in the supply of the Nile below Khartoum, the White Nile plays a smaller role than the Blue Nile, which carries abundant water (60-70% of the total flow) after the summer rains that fall on the Ethiopian Highlands. The highest flow on the lower Nile during this period is approximately five times higher than the flow during low water. The tributaries of the Nile, flowing from the Ethiopian Highlands, bring large amounts of silt, which settles during the flood. Before the construction of the Aswan High Dam, there was no through navigation route along the Nile due to numerous rapids. Overcoming rapids throughout the year was only possible by boat. For permanent navigation, areas between Khartoum and Juba, Aswan and Cairo, Cairo and the mouth of the Nile were used. Several dams and reservoirs have been built on the Nile to regulate water flow throughout the year. At one time, a large hydroelectric complex was created near Aswan to irrigate cotton fields. However, these outdated hydraulic structures did not solve the most important economic problems - expanding acreage and obtaining cheap energy. With the help of the Soviet Union in the late 60s. A large dam was built in the Nile Valley near Aswan, thanks to which the area of ​​Egypt's irrigated land was increased by 1/3, the electricity necessary for the development of the country's economy was generated, and navigation conditions were improved. Above the dam, in a flooded valley, a huge reservoir was formed, called Lake Nasser.

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Congo River

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The Congo ranks second among African rivers in terms of length, but in terms of basin area and water content, the Congo ranks first in Africa and second in the world after the Amazon. The sources of the Congo are considered to be the Lualaba and Chambeshi rivers (a tributary of the Luapula, which flows into the Lualaba). The length of the river from the first source is 4320 km, from the second - 4700 km. The basin area is about 3.7 million km2. The average annual flow rate at the mouth is 46 thousand m3/s, i.e. it is more than 15 times the average flow of the Nile. The Congo flows in the northern and southern hemispheres, crossing the equator twice. Before flowing into the Atlantic Ocean, the river cuts through a highly elevated array of crystalline rocks. Large tributaries of the Congo are the Ubangi, Sanga (right), Kwa (Kasai), Ruki, Lomami (left). The upper reaches of the Congo and its tributaries, crossing high plateaus and mountains, are replete with rapids and waterfalls. The rivers form seven waterfalls at the equator, named after the African explorer Stanley. Stanley Falls (or, as they now appear on maps, Boyoma Falls) ends the upper section of the Congo. In the middle reaches, within the basin, the Congo flows calmly in a wide valley. The river bed in some places forms lake-like extensions, reaching 20 km in diameter. Here the Congo receives its largest tributaries. In the lower reaches, cutting through the crystalline massif, the Congo again forms a series of waterfalls (there are 32 of them), united by the common name of Livingston Falls. Having reached the coastal plain, the Congo expands, reaches great depths (up to 70 m) and becomes navigable. The river at its mouth splits into branches and ends in a wide and deep estuary. In the Atlantic Ocean, the Congo channel continues in the form of an underwater groove at a distance of 150 km from the coast. Large masses The waters carried out by the Congo desalinate the ocean at a distance of several tens of kilometers. The huge amount of Congo's flow is explained by the near-equatorial position of the basin and the fact that the river receives inflows from the northern and southern hemispheres, in which maximum precipitation occurs at different times of the year. Northern tributaries bring the bulk of water to the Congo from March to November. The discharge in the middle and lower Congo, gradually increasing, reaches a maximum in October-November. The second maximum, more significant, is associated with rains in the southern hemisphere and occurs in February - April. The diet and regime of the Congo and the Amazon have much in common. During floods, the Congo in its middle reaches overflows its banks and floods the flat surface of the basin for hundreds of kilometers. All rivers of the Congo Basin have enormous reserves of water energy. Several hydroelectric power plants have been built in the Shaba region, the most important mining area within Democratic Republic Congo.

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Niger River

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The Niger River is inferior to the Congo and the Nile in terms of length and basin area, but is still one of the largest rivers Earth. The length of the Niger is 4184 km, the basin area is more than 2 million km2. Its average annual flow significantly exceeds the flow of the Nile (9300 m3/s). The Niger begins on the North Guinea Upland, at an altitude of 900 m. Its sources are located just a few tens of kilometers from the ocean, from where the Niger flows first to the northeast, and on the border of the Sahara it sharply changes direction to the southeast. In this part of the basin there is the vast inland delta of the Niger, formed during the period of the existence of an ancient reservoir into which the upper Niger carried its waters. Flowing into the Gulf of Guinea, the river forms a vast delta. The largest tributary of the Niger, the Benue, flows into it in its lower reaches from the left. In the upper and lower reaches of the Niger there are rapids, on average it has the character plain river. The peculiarities of the Niger regime are due to the fact that its upper and lower reaches are located in areas rich in precipitation, and the middle reaches basin is characterized by great dryness and strong evaporation. There are two floods in the lower reaches of the Niger, and one in the middle and upper reaches. Flood in the upper reaches depends on summer rains, lasts from June to September and is transmitted downstream. In the middle reaches there is a gradual rise in level. The Niger is flooded, water fills numerous branches, and dry riverbeds accompanying the main watercourse. Due to the dry climate, a lot of water in the middle reaches is spent on evaporation; this flood is transmitted to the lower reaches in a weakened form around January. In the lower reaches there is another flood associated with local summer rains. On the border with the Sahara, Niger is of great importance in the irrigation system: several dams and canals have been built there, and a large rice growing area has been created.

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Zambezi River

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The Zambezi is South Africa's largest river and the largest mainland river flowing into the Indian Ocean. Its length is 2736 km, the basin area is 1330 thousand km2. The average annual flow of the Zambezi is very high (16,000 m3/s): it is more than 1.5 times the flow of the Niger and many times the average flow of the Nile. The Zambezi originates at an altitude of more than 1000 m on the Congo-Zambezi watershed plateau. On its way, the river crosses flat basins and plateaus separating them, forming numerous rapids and waterfalls. The largest waterfall on the Zambezi and one of the largest in the world - Victoria - has a height of 120 m and a width of 1800 m (). The water rushes into a basalt gorge located perpendicular to the river bed. For the deafening noise of falling water, which can be heard at a great distance, and the snow-white column of spray local residents They gave the waterfall a figurative name - “thundering smoke”. Lake Nyasa (Malawi) through the Shire River has a drainage into the Zambezi. Floods on the Zambezi occur in the summer of the southern hemisphere. The navigability of the Zambezi due to sharp fluctuations in water content is small. For large vessels it is accessible only in the lower reaches for 450 km. The hydropower resources of the Zambezi are used by countries located in its basin. Below the Victoria Falls in Zimbabwe, the powerful Kariba hydroelectric complex was built, above the dam of which a reservoir of the same name was created - one of the largest in the world. Another large hydroelectric complex, Cahora Basa, is located on the territory of the Republic of Mozambique, and the energy it generates is used by several countries in Southern and Eastern Africa.

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Great African Lakes

The African Great Lakes are several large lakes located in and around the East African Rift Zone.
List of lakes:
Tanganyika
Victoria
Albert
Edward
Kivu
Malawi
Some consider only Lakes Victoria, Albert and Edward to be Great Lakes, since only these three lakes drain into the White Nile. Tanganyika and Kivu drain into the Congo River system, and Malawi drains into the Zambezi via the Shire River.

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Great Lakes Region

Great Lakes Region

The region is one of the most densely populated in the world, with approximately 107 million people. Due to past volcanic activity, this part of Africa contains some of the best grassland in the world. The altitude above sea level determines the relatively temperate climate, despite the equatorial position. Due to population density and agricultural surpluses, the Great Lakes region was historically divided into a number of small states, the most powerful of which were Rwanda, Burundi, Buganda and Bunyoro. Due to the long search for the source of the Nile, the region for a long time attracted the interest of Europeans. The first Europeans to arrive there were missionaries who found no laurels in converting the aborigines to Christianity, but opened up the region for subsequent colonization. Increased contact with the rest of the world led to several devastating epidemics that affected both people and animals. As a result, the region's population has dropped by almost 60% in some areas. It was not until the 1950s that the region's population reached pre-colonial levels.

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Lake Victoria

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Victoria - lake in East Africa, in Tanzania, Kenya and Uganda. Located in the tectonic trough of the East African Platform, at an altitude of 1134 m. It is the second largest freshwater lake in the world after Lake Superior and the largest lake in Africa by area. It is also the largest among tropical lakes. The lake was discovered and named in honor of Queen Victoria by British traveler John Henning Speke in 1858.

Area 68.870 thousand km², length 320 km, maximum width 275 km. It is part of the Victoria Reservoir. Many islands. The high-water Kagera River flows in and the Victoria Nile River flows out. The lake is navigable; local residents fish on it. The northern coast of the lake crosses the equator. The lake, with a maximum depth of 80 m, is a fairly deep lake. Unlike its deep-sea neighbors Tanganyika and Nyasa, which lie within the African gorge system, Lake Victoria fills the shallow depression between the eastern and western sides of the Great Gorge valley. The lake receives a huge amount of water from rain, more than from all its tributaries. 30 million people live in the vicinity of the lake. On the southern and western shores of the lake live the Haya people, who knew how to grow coffee long before the arrival of Europeans. Main ports: Entebbe (Uganda), Mwanza, Bukoba (Tanzania), Kisumu (Kenya), near the northern coast of Kampala, the capital of Uganda.

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Lake Albert

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Albert is a lake in East Africa, on the border of Uganda and the Democratic Republic of the Congo. In Uganda it is called Lake Nyanza, in Congo (Zaire) in 1973-97 it was called Mobutu Sese Seko in honor of President Mobutu. Located at an altitude of 617 m. Area 5.6 thousand square meters. km, depth up to 58 m. It lies in a tectonic depression in the Central African graben system. The banks are poorly dissected, mostly steep; the bottom is flat. The Semliki (Lake Edward drainage) and Victoria Nile (Lake Victoria drainage) rivers flow into the lake, and the Albert Nile River flows out. The average annual flow of water into the lake due to precipitation is 4.6 cubic meters. km, due to the runoff from the pool 24.9 cubic meters. km, evaporation is 7.5 cubic meters. km, stock 22 cubic meters. km, water temperature on the surface is up to 30 °C. Rich in fish (over 40 species: Nile perch, tiger fish and etc.). Shipping. The main ports are Butiaba (Uganda), Kasenyi (DRC).
Discovered in 1864 by the English traveler S.W. Baker and named after the husband of Queen Victoria (see Albert of Saxe-Coburg-Gotha), after whom, in turn, another great lake in Africa, Victoria, was named.

Lake Albert is part of a complex system of reservoirs in the upper Nile. The main rivers flowing into the lake are the White Nile (known locally as the Victoria Nile), flowing from Lake Victoria to the southeast through Lake Kyoga, and the Semliki River, flowing from Lake Edward to the southwest. Victoria Nile water contains much less salts than Lake Albert water. The river flowing from Albert, in the northernmost part of the island, is called the Albert Nile, which becomes the White Nile in the north. In the southern part of the lake, at the confluence of the Semliki River, there are swamps. Further south lies the Rwenzori Range, and a series of hills called the Blue Mountains dominate the north-west coast. There are several villages on the shore of the lake, including Butiaba and Pakwach.

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African waterfalls

Tugela (cascade) 933 m. Tugela (South Africa)
Kalambo (cascade) 427m r. Kalambo (Tanzania-Zambia border)
Augrabis (cascade) 146m r. Orange (South Africa)
Victoria 120m r. Zambezi (border between Zambia and Zimbabwe)
Kabarega 40m r. Victoria Nile (Uganda)
Boyoma (cascade) 40m r. Zaire (Democratic Republic of Congo), Congo

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Tugela Falls

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Tugela is the second highest waterfall in the world. It consists of five free-falling cascades, the largest of which is 411 meters.
The Tugela falls in a narrow ribbon from the eastern cliff of the Drakensberg Mountains, in the Royal Natal National Park in KwaZulu, Natal Province, South Africa. It is clearly visible after heavy rain or at the end of the day, shining from the reflection of the Sun. The source of the Tugela River is located in Mont-Aux-Sources, a few kilometers from the cliff from which the waterfall falls. The water above the falls is clean and safe to drink. The cliff is often covered with snow in winter months. There are two paths leading to the waterfall. One mountain hiking trail to the top of Mount-Aux-Sources starts in Witsieshoek, from where there is a relatively short climb to the top along a path and then over two suspension bridges. Another trail starts in the Royal Natal National Park. The seven-kilometre climb along the gorge meanders through native forest before boulder hopping and a small suspension bridge leads to the base of the Tugela Falls.

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Augrabies Falls - “a ferocious riot of the water element.”

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Augrabies Falls is located in the north-west of South Africa, almost at the very border with Namibia. Modern territory The national park spreads over 10 thousand hectares, which combine deserts, semi-deserts and areas of floodplain thickets. All this biodiversity is located in the area of ​​​​the famous 130-meter Augrabies Falls on the Orange River. Augrabies Falls National Park was created in 1966. The Orange River, on which the Augrabies Falls are located, is the largest river in South Africa. This river received its modern name from the Dutch Boer settlers, who christened it in honor of the Dutch ruling house Princes of Orange (in Dutch - Orange). The Orange River carries a mighty water flow; it is only twice as rich in water as the Niger. The river originates in the Drakensberg Mountains, where it rises above the coast Indian Ocean almost 4 km, then follows the High Veld plain, after which it merges with its main tributary, the Vaal River. After long wanderings throughout the African continent, Orange flows into the Atlantic Ocean. Augrabisu Falls along the Orange River is preceded by a 7-kilometer delta with a large number small islands, from where this powerful water flow rushes into a narrow gap. In the area of ​​Augrabis Falls, the river flow during flood exceeds 1000 cubic meters. m per second. Having flown almost 140 meters, the river hits the rocky shores, and already below the waterfall waves rise as high as a two-story house. The name of the waterfall was invented by the local Hottentots; translated from their language, Augrabis means “a very noisy place.” The Hottentots are still afraid to approach the waterfall; they are sure that an evil deity lives in a deep pool under Augrabis, and as if it was his terrible roar that resounds over the water. Among others, there is a local legend about a large treasure of diamonds at the bottom of the waterfall, as if the Orange River itself brought them to the site of the waterfall from the upper Vaal, where diamond deposits have long been known. In general, the Orange River becomes full-flowing only for a short period of time - during the rainy season. And for most of the year it is a rather inconspicuous river. But even in the dry season, the basin of the waterfall is full of water. But at this time, the so-called wells are clearly visible here - over many centuries, falling water has hollowed out quite deep “wells” at the bottom of the basin.

Victoria, Victoria Nyanza, Ukerewe (Victoria, Victoria Nyanza) is a lake in East Africa, in the territory of Tanzania, Kenya and Uganda. Located in the tectonic trough of the East African Platform, at an altitude of 1134 m. The 2nd largest freshwater lake in the world after Lake Superior and the largest lake in Africa.
Area 68 thousand sq. km, length 320 km, maximum width 275 km. It is part of the Victoria Reservoir. Many islands. The high-water Kagera River flows in and the Victoria Nile River flows out. The lake is navigable; local residents fish on it.
The northern coast of the lake crosses the equator. The lake, with a maximum depth of 80 m, is a fairly deep lake.
Unlike its deep-sea neighbors Tanganyika and Nyasa, which lie within the African gorge system, Lake Victoria fills the shallow depression between the eastern and western sides of the Great Gorge valley. The lake receives a huge amount of water from rain, more than from all its tributaries.
Its waters are home to a huge number of crocodiles, and the lang fish (fish) that lived here 300 million years ago still lives here. She can inhale and hold air in her gills, like in her lungs. This rare fish is a link between ordinary fish and land animals.

Lake Chad (Tchad, Chad, in Arabic Bar es Salaam) is an endorheic relict lake located in central Africa. Located at an altitude of 240 m above sea level.
The surface of the lake is not constant: usually occupying about 27 thousand square meters. km, the lake in the rainy season overflows to 50 thousand, and in the dry season it shrinks to 11 thousand square meters. km. From the south, the rivers Shari with a wide and shallow delta and Mbulu flow into the lake, from the west - Komadugu-Vaube, and from the east - the shallow Bar el-Ghazal. According to Nachtigall, the influx of water through rain and rivers is 100 cubic meters. km, and the loss of water through evaporation is 70 cubic meters. km. Due to the absence of a visible source of water from the lake, while the water of the lake remains fresh, Nachtigall suggests the existence of an underground channel in the northeast direction to the Aegean and Borku. Near the river mouths the water in the lake is fresh, in the rest of the lake it is slightly brackish; the insignificance of mineralization is apparently explained by permanent shift water in the lake due to the underground outflow of infiltration water. In a very rainy season (which happens extremely rarely), with extraordinary high levels the water's edge, a temporary surface runoff of the lake is formed in the north-east (along the dry bed of the Bahr el-Ghazal). The dark, dirty water of the lake is thickly overgrown with algae in places. From July to November, under the influence of rains, the water level gradually rises and the low southwestern coast is widely flooded almost to Cook. Over a considerable area, the lake is very shallow (you can wade across it on horseback); The western part near Ngornu and Maduari is distinguished by great depth. The maximum depth during the rainy season is 11 meters. The banks are mostly marshy and overgrown with papyrus; to the northeast the area has the character of a steppe, and only the southern coast is distinguished by rich tropical vegetation.
In the eastern part, the lake is covered with a network of islands (up to 100 in number), of which the Buduma, Karka and Kuri groups are inhabited (up to 30 thousand people) by people from neighboring tribes (Buduma, Kuri, Kanemba, Kanuri, Bulala and Datsa).
In 2006, the lake with an area of ​​23 thousand square kilometers, located on the borders of Nigeria, Niger, Cameroon and the Republic of Chad, shrank 26 times and continues to dry out, which became known thanks to Earth monitoring carried out by the international Disaster Monitoring Constellation system. It is known that Chad is drying out for the seventh time in the last millennium. Scientists-paleontologists established this from the remains of animals found there.

Information
photo from the site

The African freshwater lake system contains the largest and deepest lakes in the world. Many of them are part of the so-called Great African lakes, which are associated with the Nile. Near the lakes there are various attractions, starting with monuments of ancient history in places archaeological excavations from discovering fossils dating back several million years to tourist coastlines offering a variety of excursions and water sports.

Surrounded by Kenya, Uganda and Tanzania, Lake Victoria is the largest freshwater lake in Africa and the second largest freshwater lake in the world. Here local fishermen catch telapia, hunt waders, kingfishers, herons and other animals. The waters of the lake are not intended for swimming, but there are many attractive places concentrated here.

On the island of Mfangano, surrounded by lake waters, live the most various types birds, as well as white-throated otters, monkeys and lizards living in the lush jungle. Archeology buffs should visit Rusinga Island, where fossils dating back more than 18 million years have been found, including the first complete skull of a proconsul, one of the greatest species in human evolution.

Lake Nyasa is the eighth largest lake in the world (the government of Malawi gave it the name Lake Malawi). Nyasa, a long but narrow lake, is the second deepest lake in Africa and the third largest lake in the East African Rift Valley. It borders Malawi, Mozambique and Tanzania: on the shores of the lake there are fishing villages that produce tilapia, kampango and other types of fish that are very important for the local economy. The shores of the lake on the Malawi side have developed a tourism business, with Nyasa's clear waters safe for sailing, scuba diving, snorkeling, water skiing and kayaking. The least developed beach is Matama Beach, located on the northern coast: the beach boasts golden sand and warm, clear waters where you can swim or just admire the scenery.

Located behind Africa's largest man-made dam, Lake Kariba straddles the border of Zambia and Zimbabwe and is the fourth largest man-made lake in the world. There is a thriving fishing industry here, with tiger fish, bream and kapenta (tiny sardine-like fish) found in the lake's waters. The lake offers tourists a variety of activities, including fishing, motorboat rentals, water sports, houseboat cruises or simply relaxing on the beach. However, swimming in the lake is not recommended. There are several lakeside lodging options, including campsites.

Lake Albert is the seventh largest lake in Africa, it is located in the rift valley: its length is 145 km and its width is 32 km. It is shared by Uganda and the Democratic Republic of Congo and is part of the upper Nile system. The Ugandan coast has little tourism infrastructure, offering bird watching excursions, horseback riding, fossil exploration, village fishing, and walking and cycling trails. You can swim in the lake, and it is surrounded by a fairly spacious shore.

Lake Tanganyika is the seventh largest lake on earth, the longest freshwater lake and the second deepest lake in the world. In some places the depth of the lake reaches 1432 meters. Countries around the lake include Tanzania, Zambia, Burundi and the Democratic Republic of Congo. The waters of Tanganyika are so clean and clear that tourists have the opportunity to snorkel or scuba dive and see more than 350 species of fish. Located on the shore of the lake National parks Mikumi and Katavi, where you can see the best wild chimpanzees in the world.

Based on the origin of the lake basin in Africa, there are 3 types of lakes: 1) tectonic, 2) relict, 3) volcanic.

The lakes of East Africa are for the most part of tectonic origin. The Great Lakes are created by the Great Rifts. Most of these lakes lie at the bottom of rift basins, which began to fill with water almost from the moment of their origin (or, more precisely, their revival as a result of newest movements earth's crust). Among the rift lakes there are large and small, deep and shallow, fresh and salty. But almost all of them have a characteristic elongated shape, determined by the outlines of the rifts themselves. As a rule, lakes are located in fault depressions (grabens) in a row, one after another, forming long chains or garlands. The first thing that catches your eye when looking at the physical map of East Africa is a unique chain of large lakes, starting in the south with Nyasa and continuing with the Western Rift lakes - Rukwa, Tanganyika, Kivu, Edward and Albert. Another lake garland is located on the territory of the Eastern Rift and its spurs; Here, however, there is only one large lake - Rudolf, but there are many small ones. Mveru stands somewhat apart from the lakes of fault origin: it occupies an independent graben, which is believed to be a side branch of the Western Rift, but has no direct connection with it in the modern topography. Almost all large lakes in Africa lie in deep rift basins (grandiose faults in the earth's crust) on the East African Plateau and are classified as tectonic (Tanganyika, Nyasa, Edward, Albert, Kyoga, Mweru Rudolf, Victoria). Most of them are deep and bordered by steep slopes. Basins of lakes Tanganyika and Nyasa. Tectonic and volcanic processes in East Africa did not occur simultaneously, but over a very long period. It is therefore natural that East African lakes have different ages. Among them there are “old people”, formed millions of years ago, there are also “young people”, whose age is measured “only” in thousands of years (and in some small lakes - hundreds and even tens of years). Almost all large lakes are considered “old people”. They have undergone a long and complex evolution. Their level and outlines changed repeatedly depending on the movements of the earth's crust and climate fluctuations, primarily moisture conditions. During eras of humid climates, the size of the lakes increased, and some bodies of water now isolated from each other merged together. On the contrary, during dry periods the area of ​​lakes was greatly reduced, and many of them dried up altogether. All these and other features of their history left a noticeable imprint on the modern appearance of lake basins and the lakes themselves, and had a strong influence on the development of life in lake waters.

From a hydrographic point of view, the lakes of East Africa can be divided into four large groups. The first is formed by the famous Nile lakes. The upper, “head”, natural reservoir of the Nile system is Lake Victoria, which receives many tributaries - including the Kageru, the source of the Nile farthest from the mouth. Emerging from this vast natural reservoir, the Victoria Nile River flows through shallow Lake Kyoga and then flows into Lake Albert; this latter also receives the Semliki River - the drainage of Lake Edward. Finally, the Albert Nile River emerges from Lake Albert - the upper reaches of the White Nile, the main (in length) branch of the great African river, which ends its path by flowing into the Mediterranean Sea.

The second group consists of four lakes belonging to the Conto basin, and thereby to the Atlantic Ocean basin. Two of them, Bangweulu and Mweru, are parts of a complex lake-river system (Chambeshi River - Lake Bangweulu - Luapula River - Lake Mweru - Lovua River), which is considered the eastern source of the Congo. The other two lakes, Kivu and Tanganyika, connected by the Ruzizi River, flow into the Congo (Lualaba) through the Lukugu River.

The third hydrographic element is Lake Nyasa, which sends its waters along the Shire River to the Zambezi. Apart from this, there are no large lakes belonging to the Indian Ocean basin in East Africa.

The fourth and final group can include numerous lakes that do not drain into the ocean. These are, firstly, all the lake reservoirs of the Eastern Rift from Lake Rudolf in the north to Lake Manyara in the south; secondly, Lake Rukwa in the southern branch of the Western Rift; thirdly, Lake Shirva in one of the side spurs of the Nyasa rift. Unlike the lakes of the three previous groups, in which the water is fresh (only in Kivu it is brackish), the reservoirs of the fourth group are mostly salty. In addition to those listed, there are other closed lakes in East Africa (for example, many crater lakes), but they are all insignificant in size and are not of particular interest to us now.

Nyasa is a tectonic lake formed as a result of a fracture in the earth's crust. Depression is a depression earth's surface, the bottom of which lies below ocean level, crypto is a prefix to the name of the structure, denoting its thin appearance. The third largest and most southern of the lakes of the Great Rift Valley in East Africa, which fills a deep depression in the earth's crust between Malawi, Mozambique and Tanzania. The lake runs from north to south, length is 560 km, depth is 706 m. It is the ninth largest and third deepest (after Baikal and Tanganyika) among freshwater reservoirs in the world. It contains 7% of the world's liquid fresh water and creates the most diverse lake ecosystem in terms of the number of species, most of which are endemic.

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The lake fills a crack in the earth's crust at the southern end of the Great Rift Valley, as a result of which it is elongated in the meridional direction and has a length of 584 km, its width varies from 16 to 80 km. The surface of the lake lies at an altitude of 472 m above sea level, its area is 29,604 km², the average depth is 292 m, the maximum is 706 m, that is, the deepest places of the lake are below sea level. The total volume of the lake is 8,400 km³. The depths gradually increase from south to north, where the steep slopes of the mountains surrounding the lake suddenly burst straight into the water. Elsewhere on the coast, the mountains and peaks that rise along the edges of the rift valley are separated from the lake by a wide coastal plain; at the confluence of the lake big rivers The coastal plain expands and connects with the river plain, going deeper into the mountain ranges. As a result, the coastline topography varies from rocky cliffs to extensive beaches. The coastal plains are especially wide in the northwest, where the Songwe River flows into the lake, as well as in the southern part of the coast.

The bottom of the lake is covered with a thick layer of sedimentary rocks, in some places up to 4 km thick, which indicates the great age of the lake, which is estimated at least several million years.

The main part of the lake basin is occupied by highlands and mountains, which are the boundaries of the rift valley. The highest of them are the Livingstone Mountains in the northeast (up to 2000 m) and the Nyika Plateau and the Vipya and Chimaliro Mountains in the northwest and the Dowa Hills in the west; in the south the terrain gradually decreases. The lake basin is much wider to the west of the lake. In the east, the mountains come close to the water, and the basin narrows, expanding only in the northeast thanks to the Ruhuhu River, which cuts through the Livingston Mountains. The lake is fed by 14 year-round rivers, including the most important Ruhuhu, Songwe, North and South Rukuru, Dwangwa, Bua and Lilongwe . The lake's only external drainage is the Shire River, which emerges from the lake in the south and flows towards the Zambezi. Despite the large volume of the lake, the volume of its flow is small: of the approximately 63 km3 of water entering the lake annually, only 16% flows through the Shire River, the rest evaporates from the surface. Because of this, the lake has a very long water renewal period: it is estimated that all the water in the lake is renewed within 114 years. Another consequence of the fact that the main losses of water occur due to evaporation, and not runoff, is the increased mineralization of lake water compared to the waters of the rivers flowing into it - the water in the lake is hard and brackish. The waters of the lake are vertically distributed into three layers, which differ in the density of water due to its temperature. The thickness of the upper layer of warm water (epilimnion) varies from 40 to 100 m, reaching a maximum in the cool, windy season (May to September). It is in this layer that the growth of algae occurs, which is the basic element of the entire food pyramid of the lake. The middle layer, the metalimnion, is several degrees cooler than the top layer and extends from its lower edge to 220 m in depth. In the thickness of this layer, vertical movements of biological substances and oxygen dissolved in water occur. The space from the lower level of the metalimnon to the bottom of the lake is occupied by the hypolimnon. The water here is even colder (has the highest density) and has a high concentration of dissolved nitrogen, phosphorus and silicon - products of decomposition of organic matter. This area is almost completely free of dissolved oxygen, and therefore deeper than 220 m the lake is practically devoid of life.

Although these water layers are never completely mixed, a slow exchange of water between adjacent layers does occur. The volume and speed of this exchange depends on the place and time of year. The greatest influx to the surface of the rich nutrients water from metalimnon and hypolimnon occurs during the cool windy season from May to September, when the westerly wind, which the locals call mwera, blows continuously. This wind disturbs the surface of the lake, sometimes causing strong storms, and mixes the water to a considerable depth. In addition to simple mixing, in some places of the lake during this time of year there is a constant transport of deep water to the surface, the so-called upwelling. Due to the peculiarities of the bottom morphology, the upwelling is especially powerful in the southeastern bay of the lake. As a result, during the windy season and for a short time after its end, the highest concentration of plankton is observed here.

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Tanganyika is a large lake in Central Africa tectonic origin. The second deepest lake (1435 m) in the world after Lake Baikal (1620 m) and the largest in the world in length (650 km). The water level in the lake depends on the amount of rain that feeds the rivers flowing into the lake. The lake is a runoff lake, the flow occurs through the Lukuga River in the city of Congo. The water temperature in the upper layer fluctuates throughout the year from +23 to +270 C, and at a depth below 400 m it does not change and is +230 C. Lake Tanganyika is distinguished by the uniqueness of its organic world. The lake is exceptionally rich in fish: in total there are about 250 species of fish, and 7 of them are endemic. On the shores of the lake there is national park, in which lions, leopards, hippopotamuses, buffalos, antelopes, zebras, chimpanzees and other animals are found. The shores of the lake belong to four countries - the Democratic Republic of the Congo, Tanzania, Zambia and Burundi. Lake Tanganyika is located in the deepest tectonic depression in Africa, at an altitude of 773 meters above sea level and is part of the ancient East African Rift System. An underwater threshold divides the lake into two deep-water basins. The lake is part of the Congo River basin, one of the largest rivers in the world. The lake was discovered in 1858 by English travelers R. Burton and J. Speke. Coastal landscapes, as a rule, are huge cliffs and only on the eastern side the shores are gentle. On the west coast, the steep sidewalls of the East African Rift Zone that form the coastline reach 2000 m in height. The coastline is dotted with bays and bays. The largest of them is Burton Bay. The lake is fed by several tributaries; the basin area is 231 thousand km2. The largest inflowing river is the Ruzizi, the delta of which is located in the northern part of the lake. From the eastern side, the Malagarasi River flows into the lake. The Malagarasi is older in origin than Tanganyika and in the past flowed directly into the Congo River. The only river that flows out is the Lukuga, which begins in the middle part of the west coast and flows west, connecting with the Zaire River, which flows into the Atlantic. The annual flow of water into the lake is 64.8 km³, of which 40.9 km³ comes from precipitation (63%) and 23.9 km³ from tributaries (37%). A significant share of water consumption is evaporation - 61.2 km³ (94.4%), the volume of flow through the Lukuga is estimated at 3.6 kmі (5.6%). average temperature surface 25 °C, pH average 8.4. The considerable depth of the lake and its location in tropical zone create conditions under which there is no water circulation in the reservoir, that is, the lake is a meromictic reservoir in which bottom layer water does not mix with the upper layers. In terms of volume of anoxic waters, Tanganyika ranks second after the Black Sea. It is also likely that at different historical times Tanganyika could have had different inflows and sources from modern ones. The waters of Lake Rukwa could flow into it, and it could flow out into Lake Malawi and the Nile. Due to the lack of water supply, there are concerns that any increase in temperature and evaporation due to climate change could cause the lake's water level to drop extremely quickly.

The lake is divided into three volumetric basins: the Kigoma basin in the northern part with maximum depth 1310 meters, Kungwe Basin in the middle with a maximum depth of 885 meters and Kipili Basin in the southern part with a maximum depth of 1410 meters.

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Lake Kivu (area - 2.7 thousand km2, greatest depth - about 500 m) lies north of Lake Tanganyika in the depression of the same western branch of the East African rifts in which Lake Tanganyika lies. The basin of the lake is dammed with lava flows, so the origin of the lake is volcanic-tectonic or zagatno-volcanic. There are active volcanoes on the northern shore of Lake Kivu. During their eruption, powerful lava flows slide into the lake and the water in the lake boils in these places. Unlike other rift lakes, which have predominantly straight shores, Kivu has very winding shores with many picturesque bays and islands. The lake is freshwater, drainage, and the Ruzizi River flows from it, which flows into Lake Tanganyika. It is characterized by an abnormally high temperature of deep waters (+260 C), which is explained by the influence of volcanic activity and the presence of hot springs at the bottom of the lake, and the accumulation of natural flammable gas - methane. Kimvu is a lake in Central Africa, on the border between Rwanda and the Democratic Republic of the Congo in the East African Rift Valley, one of the Great African Lakes.

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Lake Kivu drains through the Ruzizi River, which flows south into Lake Tanganyika.

Scientists studying the complex mixture of chemicals lying at the bottom of Lake Kivu cannot give a definite answer - whether the reservoir will remain unchanged for another millennium or whether the gases accumulated under the water will soon break out to the surface. Over the past millennium, the concentrations of carbon dioxide and methane in the freshwater waters of Lake Kivu have steadily increased. The situation is further complicated by the fact that the region in which the lake is located is seismically dangerous and volcanic activity continues here. Lake Kivu differs in many ways from other bodies of water in both temperate and tropical climates. Its most important feature can be considered the absence of evaporation at the boundary of water and air

Because of high temperature and atmospheric humidity above the lake, a kind of stable “cushion” of hot water vapor is formed between the water and air, which stops the circulation of water molecules. As a result, the liquid does not circulate in the lake, and the gas accumulating at the bottom does not dissolve.

Lake Kivu is naturally fed by warm underwater springs that break through to the surface through a layer of hardened volcanic lava and sedimentary ash.

Periodically, the temperature of these springs changes under the influence of volcanic activity and climatic fluctuations, but this does not affect the overall picture. Under conditions of such stability, the gas accumulating under water is deposited in the form of a compressed layer.

The pressure holding it is also maintained at the same level, but any imbalance will lead to an explosion of the accumulated mixture of methane and carbon dioxide.

Lake Edward (Idi-Amin-Dada) lies north of Lake Kivu. Named after the son of Queen Victoria of England. The area of ​​the lake is 2.15 thousand km2, the greatest depth is 111 meters, the average depth is 17 meters. The lake is located in Central Africa, on the border between Uganda and the Democratic Republic of the Congo, a few kilometers south of the equator. The smallest of the Great Lakes of Africa. Named after Edward VII, the eldest son of Queen Victoria, after whom another great lake in Africa, Victoria, was named. The name of the lake was given by Henry Morton Stanley, who visited the lake in 1888. The lake was later renamed Idi Amin Dada in honor of the Ugandan dictator Idi Amin, but today the lake again bears its former name.

The Niamugasani, Ishasha, Rutsuru and Rwindi rivers flow into Lake Edward. Water from the lake flows north through the Semliki River into Lake Albert. Lake Edward is also connected via the Kazinga Canal to Lake George to the northeast. The lake is located at an altitude of 920 m, it is 77 km long and 40 km wide, the surface area of ​​the lake is 2325 km² (15th largest on the continent). The western shore is high and steep, the other shores are flat, marshy, covered with reeds and papyrus. The color of the water in the lake is light green aquamarine, which is associated with a large amount of phytoplankton. The lake is famous for the abundance of birds living on its shores (pelicans, cormorants, gulls, herons, ibises and many others). Herds of antelope and buffalo gather to drink, followed by lions, leopards and hyenas. Almost the entire area around the lake has been declared a nature reserve.

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Even further north is Lake Albert (Mobutu Sese Seko). Named after the husband of the Queen of England. Discovered in 1864 by the English traveler S.W. Baker. The area of ​​the lake is 5.6 thousand km2, the greatest depth is 58 m. It is a tectonic depression in the northern segment of the Western Rift, which, in turn, is part of the Great African Rift. The lake marks the border between the Democratic Republic of the Congo and Uganda. Albert is famous for the richness and diversity of fish stocks, and its shores for many species of land African fauna. The Semliki rivers (the drainage of Lake Edward) and Victoria Nile (the drainage of Lake Victoria) flow into the lake, and the Albert Nile River, one of the sources of the Nile, flows into the lake. The average annual flow of water into the lake due to precipitation is 4.6 cubic meters. km, due to the runoff from the pool 24.9 cubic meters. km, evaporation is 7.5 cubic meters. km, stock 22 cubic meters. km, water temperature on the surface is up to 30 °C. Rich in fish (over 40 species: Nile perch, tiger fish, etc.). Shipping. The main ports are Butiaba in Uganda and Kasenyi in Congo. Lake Albert is located in the Albertine Rift Valley and is part of a complex system of reservoirs in the upper Nile. The main rivers flowing into the lake are the Victoria Nile of the White Nile system, flowing from Lake Victoria to the southeast through Lake Kyoga, and the Semliki River flowing from Lake Edward, which lies to the southwest. Victoria Nile water contains much less salts than Lake Albert water. The river flowing from Albert in the northernmost part of the lake is called the Albert Nile, which further north becomes the White Nile.

The southern part of the lake, at the confluence of the Semliki River, is swampy. Further to the south stretches the Rwenzori Range, and the Blue Mountains rise above the northwestern coast. There are several villages on the shores of the lake, including the harbors of Butiaba and Kasenyi.

Lake Albert has a shape close to an elongated diamond, reproducing the outlines of the tectonic basin of the northern segment of the Western Rift, which is part of the Great African Rift. In system geographical coordinates The lake is oriented from southwest to northeast. Close to this axis, conditionally cutting the surface of the lake into two almost equal parts, lies the state border between the Democratic Republic of the Congo in the west and Uganda in the east. The bottom of the lake, as in most similar depressions, is flat and fairly even. Western region the rift in this region reaches 1900-2400 m above sea level. m., or 1300-1800 m above the lake. Eastern edge 1200-1400 m above sea level. m., or about 600-800 m above the lake.

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Lake Victoria is the largest lake in Africa and the second largest freshwater lake in the world after Lake Superior in North America(68 thousand km2). Discovered in 1858 by the English traveler D. Speke. Named after the English Queen Victoria. It is located in a huge flat trough (a trough is an oval-shaped deflection of tectonic origin on the Earth's surface), has relatively shallow depths for tectonic lakes (up to 80 m) and low-lying shores. The upper layer of water in the lake has a temperature of +23 ... +260 C. Numerous islands are scattered throughout the lake, with a total area of ​​6 thousand km2. Many rivers flow into the lake, including the Kagera - a loop of the Nile; Only one river flows out - the Victoria Nile. The shores of the lake are strongly dissected by bays, bays and peninsulas. In the bays and river mouths there are crocodiles and hippopotamuses, and numerous waterfowl. The lake is rich in fish: in total there are more than 100 species of fish. One of them - Protopterus - is interesting because it is lungfish and has gills and lungs. During the dry season, this fish burrows into the mud and breathes through its gills. The lake is fed mainly by sediments, from which it receives almost 80% of the total influx. In addition, numerous rivers, tributaries and streams flow into it. The average water inflow is 114 km3 regardless of sources. About 16 km3 comes from tributaries, and 98 km3 from precipitation. Annual evaporation from the surface reaches 93 km3. It is believed that over all the years of observation, the amount of water evaporating per year remains virtually unchanged. The average amplitude of lake level fluctuation is 0.3 m, and the maximum annual amplitude of the indicated 45-year observation is 1.74 m. The lake level largely depends on the amount of rain. In recent years they have declined, which is explained, in addition to the general warming of the Earth's climate, also by the destruction of the forests of Africa, and the area around the lake. In 2010, the lake level reached its lowest level in 80 years and is almost one meter lower than in 1990. The lake's water level has been measured since 1896. Its level was recorded in 1906 and 1917, but it remained relatively stable until 1961 of the year.

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The relict lakes of Africa are Chad, Tumba, Mai-Ndombe, Ngami. The largest of the relict lakes of the continent is the freshwater (according to some sources, brackish) drainless Lake Chad, located at the southern border of the Sahara Desert in a huge flat basin of the same name. The name of the lake is translated from the language of the local population as “a large expanse of water.” The area of ​​the lake varies from 12 thousand km2 in June-July to 26 thousand km2 in November-December, depending on the amount of precipitation and the full flow of rivers flowing into ( main river Shari). Modern Lake Chad is the remains of a huge reservoir with an area of ​​300-400 thousand km2, which existed in the Pleistocene (for comparison: the area of ​​the Black Sea is 420 thousand km2). The depths of the lake are insignificant (4-11 m). The uniqueness of the lake lies in the fact that the upper layers of the lake are fresh, and the lower layers are salty. This is explained by the fact that salt water is heavy behind fresh water and sinks down. In addition, Chad has an underground drainage along the dry Bahr el-Ghazal channel into the Bodele Basin, so its waters become saltier. In 2006, the lake with an area of ​​23 thousand km², located on the borders of Nigeria, Niger, Cameroon and the Republic of Chad, shrank 26 times and continues to dry out, which became known thanks to Earth monitoring carried out by the international Disaster Monitoring Constellation system.

The drying up of Lake Chad was also reported by NASA employees who compared space images from 2001 with images taken 38 years ago.

It is known that Chad is drying out for the seventh time in the last millennium. Paleontologists established this from the animal remains found there.

Satellite images taken by Nigeria's first satellite, Nigeria Sat-1, were part of the "The Story of a Dying Lake" exhibition held in Abuja, the capital of Nigeria.

Projects are being developed to transfer part of the flow from the Congo Basin (in particular, Ubangi), from 15 to 100 km per year.

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The relict lakes Tumba and Mai Ndombe (Leopold II) lie in the Congo Basin, Lake Ngami in the Kalahari Basin. The area of ​​Lake Mai-Ndombe (Leopold II) is 2.3 thousand km2, during rains - up to 8.2 thousand km2. The average depth of the lake ranges from 2.5 to 5 m. The shores are low, swampy. A freshwater lake in the western part of the Congo River basin, in the north-west of the Democratic Republic of the Congo. The length is about 130 kilometers. Situated on a swampy lowland. Area -- 2300 sq. km. In the north, the Lotoi River flows into the lake. Like other lakes of the Congo Basin, Mai Ndombe is the remnant of a giant endorheic lake that formed about 1 million years ago. From Lake Mai-Ndombe flow the rivers Lukeni and Kassai, which then flow into the Congo.

In the deserts and semi-deserts of South Africa, unique dry lakes of relict origin, called peni, are common. They are numerous in the sandy Kalahari Desert, where there are about 1000 of them. The bottom of the pens is covered with grass vegetation or bare and composed of lake sediments 2-3 m thick. The pens are rarely filled with water, only during heavy rains. The largest of the penivs, Etosha, is located in the north-west of the Kalahari Desert and is a flat clay basin. During the rainy season, the Etosha Basin becomes a large shallow lake, and after the rains stop it quickly turns into a swamp.

lake africa geographical

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The largest of the mainland's volcanic lakes is Lake Tana, dammed with lava flows, on the Ethiopian Highlands. The area of ​​the lake ranges from 3.1 to 3.6 thousand km2. There are many islands in the lake's waters. Many rivers flow into the lake, but one flows out - the Blue Nile. The lake is rich in fish. The height above sea level is 1830 meters. The lake is fed by four permanent rivers and numerous seasonal tributaries. The average depth is 8 meters, but during dry and wet periods it differs by almost two meters. Depending on the time of year, the surface area of ​​the lake varies from 3000 to 3500 square kilometers.

Fish are found in abundance in Lake Tana. More than 10,000 tons of fish are caught during the year. The diversity of birds is also great, they live both in coastal areas and on the islands.