African lakes. The largest lakes in Africa

Name	Greatest depth (in meters)	Height above sea level (in meters)
Victoria			Tanzania, Kenya, Uganda
Tanganyika			Tanzania, Zambia, Congo, Burundi
			Tanzania, Mozambique, Malawi
			Chad, Cameroon, Nigeria, Niger
			Kenya, Ethiopia
Mobutu-Sese-Seko			Uganda, Congo
			Zambia, Congo
Bangweulu

			Rwanda, Congo
			Uganda, Congo

According to the origin of the lake basin in Africa, 3 types of lakes are distinguished: 1) tectonic, 2) relict, 3) volcanic.

The lakes of East Africa for the most part - tectonic origin. The Great Lakes are generated by the Great Rifts. Most of these lakes lie at the bottom of rift basins, which have been filled with water almost from the moment of their origin (or, more precisely, their revival as a result of the latest 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, defined 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 chain of big lakes, starting in the south of Nyasoy and continuing with the lakes of the Western Rift - Rukvoy, 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 among 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 relief. Almost all large lakes in Africa lie in deep rift depressions (grand breaks in the earth's crust) on the East African plateau and are tectonic (Tanganyika, Nyasa, Edward, Albert, Kyoga, Mweru Rudolph, Victoria). Most of them are different great depths and bordered by steep slopes. Basins of lakes Tanganyika and Nyasa. Tectonic and volcanic processes in East Africa did not occur at the same time, but over a very long period. It is quite natural, therefore, that the East African lakes are of different ages. There are “old people” among them, formed millions of years ago, there are also “youth”, whose age is measured “only” in millennia (and in some small lakes - hundreds and even tens of years). Almost all large lakes are among the "old men". They have gone through a long and complex evolution. Their level and outlines have repeatedly changed depending on the movements of the earth's crust and climate fluctuations, primarily moisture conditions. In epochs of a humid climate, the size of the lakes increased, and some now isolated water bodies merged together. On the contrary, during dry epochs, the area of lakes was greatly reduced, and many of them completely dried up. All these and other features of their history left a noticeable imprint on modern look lake basins and the lakes themselves, 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 subdivided 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, the most distant from the mouth. flowing from this huge natural reservoir the Victoria Nile flows through shallow Lake Kyoga and then flows into Lake Albert; this latter also receives the Semliki River, the outlet of Lake Edward. Finally, the Albert Nile River emerges from Lake Albert - the headwaters of the White Nile, the main (in length) branch of the great African river, ending its journey at the mouth of the Mediterranean Sea.

The second group consists of four lakes belonging to the Conto basin, and thus to the basin Atlantic Ocean. Two of them, Bangweulu and Mweru, are links in 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, have a drain in the Congo (Lualaba) through the Lukuga River.

The third hydrographic element forms Lake Nyasa, which sends its waters along the Shire River to the Zambezi. In addition to it, large lakes belonging to the Indian Ocean basin, in East Africa No.

Numerous lakes that do not have a runoff into the ocean can be distinguished as the fourth and last group. These are, firstly, all the lake reservoirs of the Eastern Rift from Lake Rudolf in the north to Lake Manyara in the south; secondly, Rukva Lake 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 the Kivu it is brackish), the reservoirs of the fourth group are mostly salty. In addition to those listed, there are other endorheic lakes in East Africa (for example, many crater lakes), but all of them are insignificant in size and are of no particular interest to us now.

Nyasa -tectonic lake formed as a result of a break in the earth's crust. A depression is a depression on the earth's surface, the bottom of which lies below ocean level, a crypto-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 deep depression in the earth's crust between Malawi, Mozambique and Tanzania. The lake runs from north to south, 560 km long, 706 m deep. It is the ninth largest and third deepest (after Baikal and Tanganyika) among the world's freshwater reservoirs. 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 depth is 706 m, that is, the most deep places lakes are below sea level. The total volume of the lake is 8,400 km². The depths gradually increase from south to north, where the steep slopes of the mountains surrounding the lake suddenly break right into the water. In other places along the coast, mountains and peaks rising along the edges of the rift valley are separated from the lake by a wide coastal plain; at the mouth of the lake big rivers the coastal plain expands and connects with the river plain, deepening inward mountain ranges. As a result, the relief of the coastline 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 mountains of Livingston in the northeast (up to 2000 m) and the Nyika plateau and the mountains of Vipya and Chimaliro in the northwest and the Dowa upland in the west; in the south, the terrain is gradually lowered. 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 mountains of Livingston. The lake is fed by 14 year-round rivers, including the most important Ruhuhu, Songwe, North and South Rukuru, Dwangwa, Bua and Lilongwe . The only external outflow of the lake is the Shire River, which flows from the lake in the south and flows towards the Zambezi. Despite the large volume of the lake, the volume of its runoff is small: out of about 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 term water renewal: it is estimated that all the water in the lake is renewed within 114 years. Another consequence of the fact that the main water losses 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 (from May to September). It is in this layer that algae grows, which are the basic element of the entire food pyramid of the lake. The middle layer, the metalimnion, is several degrees colder than the upper one and extends from its lower edge 220 m deep. 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 - decomposition products 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 never completely mix, a slow exchange of water between adjacent layers does occur. The volume and speed of this exchange depends on the place and season. The highest influx of nutrient-rich water from the metalimnon and hypolimnon to the surface 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 severe storms, and mixes the water to a considerable depth. In addition to simple mixing in some places of the lake during this time of the year, there is a constant removal of deep water to the surface, the so-called upwelling. Due to the peculiarities of the bottom morphology, the upwelling is especially strong in the southeastern bay of the lake. As a result, during the windy season and 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 of tectonic origin. The second deepest (1435 m) lake in the world after 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 fed by the rivers flowing into the lake. The lake is runoff, the runoff 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 the organic world. The lake is exceptionally rich in fish: in total there are about 250 species of fish, and ¾ of them are endemic. On the shores of the lake there is a national park where lions, leopards, hippos, buffaloes, antelopes, zebras, chimpanzees and other animals live. 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. The lake is divided by an underwater threshold into two deep-sea 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 rocks and only on the eastern side of the coast are gentle. On the west coast, the steep side walls of the East African Rift Zone, which form the coastline, reach 2,000 m in height. Coastline dotted with coves 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, whose delta is located in the northern part of the lake. From the eastern side, the Malagarasi River flows into the lake. Malagarasi is older in origin than Tanganyika and in the past flowed directly into the Congo River. The only outflowing river - Lukuga (Lukuga) begins in the middle part west coast and flows west, joining the Zaire River, which flows into the Atlantic. The annual inflow of water into the lake is 64.8 km³, of which 40.9 km³ falls on precipitation (63%) and 23.9 km³ - on tributaries (37%). A significant proportion of water consumption is evaporation - 61.2 km³ (94.4%), the volume of runoff through Lukuga is estimated at 3.6 km³ (5.6%). Average surface temperature 25 °C, average pH 8.4. The significant depth of the lake and its location in the tropical zone create conditions under which there is no water circulation in the reservoir, that is, the lake is a meromictic reservoir in which the lower layer of water does not mix with the upper layers. In terms of the volume of anoxic waters (eng. Anoxic waters), Tanganyika ranks second after the Black Sea. It is also likely that at different historical times Tanganyika could have different tributaries and sources from modern ones. The waters of Lake Rukva could flow into it, and it could flow out into Lake Malawi and the Nile. Due to the lack of incoming water, there are concerns that any increase in temperature and evaporation due to climate change could lead to an extremely rapid drop in the lake's water level.

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

Rice.

Lake Kivu (area - 2.7 thousand km2, maximum 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 also lies. The basin of the lake is dammed with lava flows, so the origin of the lake is volcanic-tectonic or volcanic-volcanic. On the northern shores of Lake Kivu are active volcanoes. 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, stock, the Ruzizi River flows out of it, which flows into Lake Tanganyika. It is distinguished by an abnormally high temperature of deep waters (+260 C), explained by the influence of volcanic activity and the presence of hot springs at the bottom of the lake, and the accumulation of natural combustible gas - methane in them. 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 African Great Lakes.

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Lake Kivu has a drain through the Ruzizi River, which flows into southbound and flows into Lake Tanganyika.

Scientists studying the complex mixture of chemicals that lie at the bottom of Lake Kivu cannot give a definite answer - whether the reservoir will remain unchanged for another millennium or the gases accumulated under water will soon escape to the surface. Over the past millennium, the concentrations of carbon dioxide and methane have steadily increased in the freshwater waters of Lake Kivu. 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 water bodies of both temperate and tropical climates. Its most important feature can be considered the absence of evaporation at the border of water and air.

Due to the high temperature and humidity of the atmosphere above the lake, a kind of stable “cushion” of hot water vapor forms between water and air, which stops the cycle of water molecules. As a result, the liquid in the lake does not circulate, and the gas accumulating at the bottom does not dissolve.

Lake Kivu is naturally fed by warm underwater springs that erupt to the surface through a layer of solidified 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 kept at the same level, but any imbalance will lead to an explosion of the accumulated mixture of methane and carbon dioxide.

Lake Eduard (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 maximum 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. It is named after Edward VII, the eldest son of Queen Victoria, after whom, in turn, another great lake of Africa, Victoria, is 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 dictator of Uganda, Idi Amin, but today the lake again bears its former name.

The Niamugasani, Ishasha, Rutsuru and Rvindi rivers flow into Lake Edward. Water from the lake flows in the north through the Semliki River into Lake Albert. Lake Edward is also connected via the Casinga 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 \u200b\u200bthe lake is 2325 km² (15th largest on the continent). 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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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 basin of the northern segment of the Western Rift, which, in turn, is part of the Great African Rift. The lake is 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 are rich in species of land African fauna. The Semliki (Lake Edward drain) and Victoria Nile (Lake Victoria drain) rivers flow into the lake, and the Albert Nile River flows out, one of the sources of the Nile. 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 of 24.9 cubic meters. km, evaporation is 7.5 cubic meters. km, stock 22 cub. km, surface water temperature 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 the 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 lying to the southeast through Lake Kyoga, and the Semliki River, flowing from Lake Edward, lying to the southwest. The water of the Victoria Nile contains much less salt than the water of Lake Albert. The river flowing from Albert in the northernmost part of the lake is called the Albert Nile, passing further north into the White Nile.

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

Lake Albert has a shape close to an elongated rhombus, 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, passes 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 of these depressions, is flat and fairly even. The western edge of the rift in this region reaches 1900-2400 m a.s.l. m., or 1300-1800 m above the lake. East edge 1200-1400 m a.s.l. 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 gently sloping trough (trough is an oval-shaped trough of tectonic origin on the Earth's surface), has relatively insignificant for tectonic lakes depths (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 around the lake, the total area of which is 6 thousand km2. Many rivers flow into the lake, including the Kagera - a coil of the Nile; only one river flows out - the Victoria Nile. The shores of the lake are strongly dissected by bays, bays and peninsulas. Crocodiles and hippos, numerous waterfowl are found in the bays and estuaries of the rivers. The lake is rich in fish: there are more than 100 species of fish. One of them - protopterus - is interesting in that it is lungfish and has gills and lungs. During the dry season, this fish burrows into the silt and breathes through its gills. The lake feeds mainly on precipitation, from which it receives almost 80% of its total inflow. In addition, it includes numerous rivers, tributaries and streams. The average water inflow is 114 km3 regardless of the sources. About 16 km3 comes from tributaries, and 98 km3 comes from precipitation. Annual evaporation from the surface reaches 93 km3. It is believed that over all the years of observations, the amount of water evaporating per year remains practically unchanged. The average amplitude of the 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 decreased, 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 level of the lake reached its lowest level in 80 years, it is almost one meter lower than in 1990. Measurements of the lake's water level have been carried out since 1896. The height of its level was noted in 1906 and 1917, but it remains relatively stable until 1961 of the year.

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The relic lakes of Africa are Chad, Tumba, Mai-Ndombe, Ngami. The largest of the relict lakes on the mainland 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 from the language local population translates as "great 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 the rivers flowing (the main Shari River). 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 negligible (4-11 m). The uniqueness of the lake lies in the fact that the upper layers of the lake are fresh, and the lower ones are salty. This is explained by the fact that salty waters are heavy for fresh ones and sink down. In addition, Chad has an underground runoff along the dry channel of the Bahr el-Ghazal to the Bodele basin, so its waters become saline. In 2006, the lake with an area of 23 thousand km², located on the borders of Nigeria, Niger, Cameroon and the Republic of Chad, decreased by 26 times and continues to dry up, which became known thanks to the monitoring of the Earth, carried out by the international system "Disaster Monitoring Constellation".

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

It is known that Chad dries up for the seventh time in the last millennium. Paleontologists have established this from the remains of animals found there.

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

Projects are being developed to transfer part of the flow from the Congo basin (in particular, Ubangi), from 15 to 100 km3 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 Basin, in the northwest Democratic Republic Congo. The length is about 130 kilometers. Located on a marshy lowland. Area - 2300 sq. km. In the north, the Lotoi River flows into the lake. Like other lakes in the Congo Basin, Mai Ndombe is the remnant of a giant endorheic lake that formed about 1 million years ago. The Lukeni and Kassai rivers flow from Lake Mai-Ndombe, which then flow into the Congo.

In deserts and semi-deserts South Africa peculiar dry lakes of relict origin, called peni, are widespread. They are numerous in the sandy Kalahari desert, where there are about 1000 of them. The bottom of the foams is covered with herbaceous vegetation or bare and is composed of lake sediments 2-3 m thick. The foams are rarely filled with water, only during heavy rains. The largest of the penins - Etosha is located in the northwest 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 end of the rains it quickly turns into a swamp.

lake africa geographical

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The largest of volcanic lakes mainland is Lake Tana, dammed with lava flows in the Ethiopian highlands. The area of the lake ranges from 3.1 to 3.6 thousand km2. There are many islands in the lake. Many rivers flow into the lake, one flows out - the Blue Nile. The lake is rich in fish. Height above sea level 1830 meters. The lake is fed by four permanent rivers and numerous seasonal tributaries. The average depth is 8 meters, but during the dry and wet periods it differs by almost two meters. Depending on the season, the surface area of the lake varies from 3,000 to 3,500 square kilometers.

Fish are abundant in Lake Tana. More than 10,000 tons of fish are caught during the year. The variety of birds is also great, they live both in coastal areas as well as on the islands.

The African freshwater lake system includes the largest and deepest lakes in the world. Many of them are part of the so-called African Great Lakes, which are connected to the Nile. Near the lakes there are various attractions, starting from monuments ancient history in archaeological sites that have discovered fossils that are several million years old, and ending tourist coasts where various excursions and water sports 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 telapies, hunt waders, kingfishers, herons and other animals. The waters of the lake are not intended for swimming, but many attractive places are concentrated here.

Surrounded by lake waters, Mfangano Island is home to a wide variety of bird species, as well as white-throated otters, monkeys and lizards living in the lush jungle. Archeology buffs should visit Rusinga Island, where fossils dating back over 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 (named Lake Malawi by the Malawi government). 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 hunt tilapia, campango and other fish species that are very important to the local economy. On the shores of the lake on the side of Malawi, a tourism business has developed: the crystal waters of Nyasa are safe for sailing, diving, snorkeling, boating water skiing and kayaks. The least developed is Matama Beach, located on the north coast, boasting golden sands and warm, clear waters where you can swim or just enjoy the scenery.

Situated behind Africa's largest man-made dam, Lake Kariba sits on the border of Zambia and Zimbabwe and is the fourth largest man-made lake in the world. The fishing industry thrives here: tiger fish, bream and capenta (tiny sardines like fish) live in the waters of the lake. On the lake, tourists are offered a variety of entertainment, including fishing, renting motor boats, water sports, houseboat cruises or just relaxing on the beach. However, swimming in the lake is not recommended. There are several lakeside accommodation 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 the Congo and is part of the upper Nile system. Uganda's coastline has little tourism infrastructure, offering bird watching tours, horseback riding, fossil research, 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. Around the lake are countries such as Tanzania, Zambia, Burundi and the Democratic Republic of the Congo. The waters of Tanganyika are so clear and transparent that tourists have the opportunity to go snorkeling or scuba diving and see more than 350 species of fish. On the shores of the lake are the national parks of Mikumi and Katavi, where you can see the best wild chimpanzees in the world.

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Africa is the second largest continent after Eurasia, washed by the Mediterranean Sea from the north, the Red Sea from the northeast, the Atlantic Ocean from the west and the Indian Ocean from the east and south. Africa is also called the part of the world, consisting of the mainland Africa and adjacent islands. The area of Africa is 29.2 million km², with islands - about 30.3 million km², thus covering 6% of the total surface area of the Earth and 20.4% of the land surface. There are 55 states in Africa.

The population of Africa is about a billion people. Africa is considered the ancestral home of mankind: it was here that the most ancient remains of early hominids and their probable ancestors were found.

The African continent crosses the equator and several climatic zones; it is the only continent that stretches from the northern subtropical climate zone to the southern subtropical one. Due to the lack of constant rainfall and irrigation - as well as glaciers or aquifers mountain systems-- natural regulation of the climate is practically not observed anywhere, except for the coasts.

extreme points

North - Cape Blanco (Ben Secca, Ras Engela, El Abyad)

South - Cape Agulhas (Agulyas)

Western - Cape Almadi

Eastern - Cape Ras Hafun

Africa covers an area of 30.3 million km². The length from north to south is 8 thousand km, from west to east in the northern part - 7.5 thousand km.

For the most part - flat, in the north-west are the Atlas Mountains, in the Sahara - the highlands of Ahaggar and Tibesti. In the east - the Ethiopian Highlands, to the south of it the East African Plateau, where the volcano Kilimanjaro (5895 m) is located - the highest point on the mainland. To the south are the Cape and Dragon Mountains. The most low point(157 meters below sea level) is located in Djibouti, this is the salt lake Assal. The deepest cave is Anu Ifflis, located in the north of Algeria in the Tel Atlas mountains.

The structure of the surface of the mainland is rather peculiar. The relief of Africa is vast plains giving way to high mountains and endless deserts. Plains and plateaus with a height of 200 to 1000 m predominate, there are very few lowlands. The most extensive plateaus are East African and South African. Elevated areas alternate with basins, the most extensive of which are the Kalahari Basin, the Congo Basin, etc.

The features of the relief are connected with the history of the development of the mainland. At the heart of the continent lies the ancient African-Arabian platform - part of the split Gondwana. The platform was formed in the Archean and Proterozoic and acquired greater stability over 2–3 billion years. Only the Atlas Mountains in the north and the Cape Mountains in the south were created by later movements of the earth's crust.

The huge block of Africa experienced ups and downs, while the northern part of the mainland more often sank than rose, flooded with seas. The crystalline basement of the platform is covered by sedimentary rocks and only in the center of the Sahara and on the coast of the Gulf of Guinea comes to the surface.

The relief of East and South Africa was formed differently - the uplift of the earth's crust prevailed, giant faults, horsts and grabens formed. Actively developed volcanic activity. There are many lava plains, grabens are occupied by lakes. Volcanic eruptions and earthquakes still occur today. Volcanoes are located in the rift belt, including the highest point of the mainland - Mount Kilimanjaro (5895 meters)

Africa is the hottest continent on the planet. The reason for this is the geographical location of the mainland: the entire territory of Africa is in hot climatic zones and the mainland is crossed by the equator line. It is in Africa that the hottest place on Earth is located - Dallol.

Central Africa and the coastal regions of the Gulf of Guinea belong to the equatorial belt, where heavy rainfall occurs throughout the year and there is no change of seasons. To the north and south of the equatorial belt are subequatorial belts. Here, humid equatorial air masses dominate in summer (rainy season), and in winter - dry air of tropical trade winds (dry season). To the north and south of the subequatorial belts are the northern and southern tropical belts. They are characterized by high temperatures with low rainfall, which leads to the formation of deserts.

In the north is the Sahara Desert, the largest on Earth, in the south - the Kalahari Desert, in the southwest the Namib Desert. The northern and southern extremities of the mainland are included in the corresponding subtropical belts.

High temperatures throughout the year in the main part of Africa depend on the height of the sun above the horizon and strong insolation. In a significant part of the mainland, the average annual temperature exceeds 20 °C. Northern part Africa is more massive, therefore, in general, it heats up more than southern Africa, and there is the highest average monthly (35 ... 40 ° C), as well as the highest Maximum temperature(up to 58 °C), observed on Earth.

Significant diurnal temperature fluctuations are characteristic of the whole of Africa as a manifestation of the continentality of the climate. For example, in the Sahara, daily temperature amplitudes can reach 50 °C.

Precipitation is distributed across the mainland extremely unevenly. Regular and plentiful convective rains fall in the equatorial part, approximately between 5 ° N. latitude. and 10° S The maximum precipitation in Africa (about 10,000 mm) was recorded on the slopes of the Cameroon massif, facing the prevailing southwestern winds.

Distribution inland waters closely related to topography and climate. Approximately one second of the continent belongs to the areas of internal flow, since vast areas of the mainland receive little rainfall. Where there is a lot of precipitation, the river network is dense. In other words, the river network is unevenly distributed on the mainland.

The East African Plateau is a watershed, so most of the rivers flow into the Atlantic Ocean. There are many rapids and waterfalls on the rivers of Africa, and they are of little use for navigation, but they have huge reserves of hydropower. Almost all rivers are mainly fed by rain. In areas with an equatorial climate, they are full-flowing all year round and form a dense river network. In the subequatorial belts, the rivers are full-flowing only during the rainy season. Territories with a dry tropical climate are almost devoid of surface water, but there are artesian pools. Often there are dry channels - wadis, rarely filled with water from occasional rains. On rivers in the subtropical zone, the water level rises only during the rainy season, on the coast mediterranean sea it happens in winter.

In terms of the total volume of annual runoff (5390 cubic km), Africa is inferior to Asia and South America. In terms of basin area, length, and flow volume, many rivers are among the largest in the world (Nile, Congo). The distribution of the river network and runoff over the territory of the continent is extremely uneven, which depends mainly on the difference in climatic conditions, topography and the nature of the rocks of certain areas. Along with areas with a dense hydrographic network and large lakes, the vast expanses of Africa are almost or completely devoid of a local river network. Many rivers do not reach the ocean and end in inland drainless depressions. Almost all rivers of the continent are fed by rain. Only in deserts and semi-deserts, their food is groundwater, and on the high peaks of the Atlas Mountains and East Africa, the sources of the rivers are also fed by melted waters of snow and glaciers. The rivers Congo, Zambezi, Niger, Senegal, Orange, Nile and others flow through the mainland. Nile is the most long river in the world. The rivers of Africa are full of water only in its equatorial part, since there is a lot of precipitation. Many rivers in Africa are fast, rapids, abound in waterfalls, lakes are concentrated mainly in the east, where water fills the cracks of the faults.

The total area of East African lakes, according to rough estimates, exceeds 170 thousand km2. It's halved more territory Austria and six times - Belgium. The volume of water contained in the Great African Lakes is also huge. In order to fill the deepest of them - Tanganyika, even such a superabundant river as the Congo, it would take a quarter of a century, and, say, the Volga - about 120 years (and this is not taking into account the loss of water for evaporation, with taking into account their named periods, they would have to be much longer). The largest of the Great Lakes of East Africa, Victoria, is third in area among the lakes of the world (after the Caspian and Lake Superior in North America) and second among freshwater lakes. The other two largest East African lakes, Tanganyika and Nyasa, are ranked seventh and ninth among the lakes by the same indicator. the globe, and if we count only fresh lakes, then, respectively, the fifth and seventh.

Most lakes, especially large ones, are concentrated in eastern Africa. Their basins are located in narrow elongated depressions in the East African fault zone of the earth's crust. These lakes have steep banks and great depths. The deepest in Africa and the second deepest in the world after Lake Baikal is Lake Tanganyika (1,435 m). With a width of 60 km, it stretches for 650 km! The lake is stock, so the water in it is fresh. It has a unique organic world and is exceptionally rich in fish. There are about 250 species of fish in the lake, most of which are endemic. Lake Nyasa also has an elongated shape and tectonic origin. However, it is inferior to Tanganyika in area and depth. The lake is fresh and rich in fish.

Lake Victoria is like the sea. The largest lake in East Africa and the entire mainland - Victoria - is not among the rift lakes. It occupies a vast flat basin, also created by tectonic processes, but mostly not by faults (although they seem to occur in some places along the shores of the lake), but by a slow, relatively small vertical amplitude lowering of the axial part of the East African dome. The lake occupies a gentle tectonic trough in the northern part of the East African Plateau, dammed from the north by a lava flow. It arose in the middle of the Anthropogenic period during the formation of the Albert and Edward lake basins in the central branch of the East African fault zone, which disrupted the former flow into the Congo basin. New system the runoff was turned east, to a trough on the plateau, where a huge reservoir was formed, the area of \u200b\u200bwhich was especially large in the pluvial epochs. The ancient lake received a runoff to the west, into Lake Albert and further into the Nile system through the river. Victoria Nile at the formation of Murchison Falls. Victoria and Lake Kyoga to the north are relics of an ancient reservoir. In the same shallow depressions of the ancient basement lie the Kyoga and Bangweulu lakes. It is the largest lake in Africa and one of the largest in terms of area in the world. The lake was formed not in a fault, but in a deflection of the platform. Therefore, the lake is relatively shallow (up to 80 m) and has low-lying shores, strongly dissected by bays and peninsulas. The lake is located at an altitude of 1134 m. The area is 68 thousand km², the volume is 8400 km². This is the second largest fresh lake world (after Lake Superior). Maximum length 320 km, width 274 km. The average depth is 40 m (the largest is 80 m). After the construction of the Owen Falls Dam in 1954, the lake was turned into a reservoir. There are many islands on the lake. The high-water river flows into Kagera, the river flows out. Victoria Nile. Fishing is developed on the lake (more than 100 species of fish, many endemics), shipping. The main ports are Mwanza, Bukoba (Tanzania), Entebbe, Jinja (Uganda), Kisumu (Kenya). On about. Rubondo (Tanzania) is a national park. Hurricane winds, often accompanied by thunderstorms, cause severe storms on the lake.

The oldest lake in Africa is Lake Chad, lying south of the Sahara in a huge flat depression. It is a remnant of an ancient lake that existed in past geological epochs. The lake is shallow (7 m). In the dry season, its area is halved, and in the rainy season it increases again. The shores are low-lying, swampy in many places, covered with thickets of reeds and reeds.

The role of lakes in people's lives is great. For Africa, their transport role is very important, since the rivers are “blocked” by numerous rapids. The lakes are rich in fish and are sources of fisheries.

The freshwater system of the African continent includes the largest and deep lakes on the planet. Most of them belong to the Great African Lakes, which have a connection with the Nile. But directly among the Great, many geographers include only following lakes Africa: Victoria, Edward and Albert. Because only they have a natural outlet to the White Nile. Lake Tanganyika has a natural flow into water system Congo, and Lake Malawi is connected to the Zambezi River. All lakes in Africa (photos are presented below) have very beautiful natural landscapes.

The largest lakes Africa

Name	Greatest depth (in meters)	Height above sea level (in meters)
Victoria			Tanzania, Kenya, Uganda
Tanganyika			Tanzania, Zambia, Congo, Burundi
			Tanzania, Mozambique, Malawi
			Chad, Cameroon, Nigeria, Niger
			Kenya, Ethiopia
Mobutu-Sese-Seko			Uganda, Congo
			Zambia, Congo
Bangweulu

			Rwanda, Congo
			Uganda, Congo

According to the origin of the lake basin in Africa, 3 types of lakes are distinguished: 1) tectonic, 2) relict, 3) volcanic.

The lakes of East Africa are mostly of tectonic origin. The Great Lakes are generated by the Great Rifts. Most of these lakes lie at the bottom of rift basins, which have been filled with water almost from the moment of their origin (or, more precisely, their revival as a result of the latest movements of the 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, defined 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 chain of large lakes, unique in length, starting in the south of Nyasoy and continuing with the lakes of the Western Rift - 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 among 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 relief. Almost all large lakes in Africa lie in deep rift depressions (grand breaks in the earth's crust) on the East African plateau and are tectonic (Tanganyika, Nyasa, Edward, Albert, Kyoga, Mweru Rudolph, 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 at the same time, but over a very long period. It is quite natural, therefore, that the East African lakes are of different ages. There are “old people” among them, formed millions of years ago, there are also “youth”, whose age is measured “only” in millennia (and in some small lakes - hundreds and even tens of years). Almost all large lakes are among the "old men". They have gone through a long and complex evolution. Their level and outlines have repeatedly changed depending on the movements of the earth's crust and climate fluctuations, primarily moisture conditions. In epochs of a humid climate, the size of the lakes increased, and some now isolated water bodies merged together. On the contrary, during dry epochs, the area of lakes was greatly reduced, and many of them completely dried up. 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, the most distant from the mouth. From this vast natural reservoir, the Victoria Nile flows through shallow Lake Kyoga and then flows into Lake Albert; this latter also receives the Semliki River, the outlet of Lake Edward. Finally, the Albert Nile River emerges from Lake Albert - the headwaters of the White Nile, the main (in length) branch of the great African river, ending its journey at the mouth of the Mediterranean Sea.

The second group consists of four lakes belonging to the Conto basin, and thus to the Atlantic Ocean basin. Two of them, Bangweulu and Mweru, are links in 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, have a drain in the Congo (Lualaba) through the Lukuga River.

The third hydrographic element forms Lake Nyasa, which sends its waters along the Shire River to the Zambezi. In addition to it, there are no large lakes belonging to the Indian Ocean basin in East Africa.

Nyasa is a tectonic lake formed as a result of a break in the earth's crust. A depression is a depression on the earth's surface, the bottom of which lies below ocean level, a crypto-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, 560 km long, 706 m deep. It is the ninth largest and third deepest (after Baikal and Tanganyika) among the world's freshwater reservoirs. 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.

Rice. Lake Nyasa. A picture from space.

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 depth is 706 m, that is, the deepest places of the lake are below sea level. The total volume of the lake is 8,400 km². The depths gradually increase from south to north, where the steep slopes of the mountains surrounding the lake suddenly break right into the water. In other places along the coast, mountains and peaks rising along the edges of the rift valley are separated from the lake by a wide coastal plain; in places where large rivers flow into the lake, the coastal plain expands and merges with the river plain, deepening into mountain ranges. As a result, the relief of the coastline 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 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 mountains of Livingston in the northeast (up to 2000 m) and the Nyika plateau and the mountains of Vipya and Chimaliro in the northwest and the Dowa upland in the west; in the south, the terrain is gradually lowered. 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 mountains of Livingston. The lake is fed by 14 year-round rivers, including the most important Ruhuhu, Songwe, North and South Rukuru, Dwangwa, Bua and Lilongwe . The only external outflow of the lake is the Shire River, which flows from the lake in the south and flows towards the Zambezi. Despite the large volume of the lake, the volume of its runoff is small: out of about 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 water losses 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 (from May to September). It is in this layer that algae grows, which are the basic element of the entire food pyramid of the lake. The middle layer, the metalimnion, is several degrees colder than the upper one and extends from its lower edge 220 m deep. 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 - decomposition products 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.

Rice. View of Lake Nyasa from Likoma Island.

Tanganyika is a large lake in Central Africa of tectonic origin. The second deepest (1435 m) lake in the world after 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 fed by the rivers flowing into the lake. The lake is runoff, the runoff 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 the organic world. The lake is exceptionally rich in fish: in total there are about 250 species of fish, and ¾ of them are endemic. On the shores of the lake there is a national park where lions, leopards, hippos, buffaloes, antelopes, zebras, chimpanzees and other animals live. 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. The lake is divided by an underwater threshold into two deep-sea 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 rocks and only on the eastern side of the coast are gentle. On the west coast, the steep side walls of the East African Rift Zone, which form the coastline, reach 2,000 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, whose delta is located in the northern part of the lake. From the eastern side, the Malagarasi River flows into the lake. Malagarasi is older in origin than Tanganyika and in the past flowed directly into the Congo River. The only outflowing river - Lukuga (Lukuga) begins in the middle part of the west coast and flows west, connecting with the Zaire River, which flows into the Atlantic. The annual inflow of water into the lake is 64.8 km³, of which 40.9 km³ falls on precipitation (63%) and 23.9 km³ - on tributaries (37%). A significant proportion of water consumption is evaporation - 61.2 km³ (94.4%), the volume of runoff through Lukuga is estimated at 3.6 km³ (5.6%). Average surface temperature 25 °C, average pH 8.4. The significant depth of the lake and its location in the tropical zone create conditions under which there is no water circulation in the reservoir, that is, the lake is a meromictic reservoir in which the lower layer of water does not mix with the upper layers. In terms of the volume of anoxic waters (eng. Anoxic waters), Tanganyika ranks second after the Black Sea. It is also likely that at different historical times Tanganyika could have different tributaries and sources from modern ones. The waters of Lake Rukva could flow into it, and it could flow out into Lake Malawi and the Nile. Due to the lack of incoming water, there are concerns that any increase in temperature and evaporation due to climate change could lead to an extremely rapid drop in the lake's water level.

Rice. Map of Lake Tangaika

Lake Kivu (area - 2.7 thousand km2, maximum 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 also lies. The basin of the lake is dammed with lava flows, so the origin of the lake is volcanic-tectonic or volcanic-volcanic. There are active volcanoes on the northern coast 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, stock, the Ruzizi River flows out of it, which flows into Lake Tanganyika. It is distinguished by an abnormally high temperature of deep waters (+260 C), explained by the influence of volcanic activity and the presence of hot springs at the bottom of the lake, and the accumulation of natural combustible gas - methane in them. 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 African Great Lakes.

Rice. Lake Kivu seen from space

Lake Kivu has a drain through the Ruzizi River, which flows in a southerly direction and flows into Lake Tanganyika.

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

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

Rice. Lake Edward photographed from space.

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

Lake Albert has a shape close to an elongated rhombus, reproducing the outlines of the tectonic basin of the northern segment of the Western Rift, which is part of the Great African Rift. In the geographic coordinate system, the lake is oriented from southwest to northeast. Close to this axis, conditionally cutting the expanse of the lake into two almost equal parts, is 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 of these depressions, is flat and fairly even. The western edge of the rift in this region reaches 1900-2400 m a.s.l. m., or 1300-1800 m above the lake. Eastern edge 1200-1400 m a.s.l. m., or about 600-800 m above the lake.

Rice. physical map Lake Albert.

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 trough 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 around the lake, the total area of which is 6 thousand km2. Many rivers flow into the lake, including the Kagera - a coil of the Nile; only one river flows out - the Victoria Nile. The shores of the lake are strongly dissected by bays, bays and peninsulas. Crocodiles and hippos, numerous waterfowl are found in the bays and estuaries of the rivers. The lake is rich in fish: there are more than 100 species of fish. One of them - protopterus - is interesting in that it is lungfish and has gills and lungs. During the dry season, this fish burrows into the silt and breathes through its gills. The lake feeds mainly on precipitation, from which it receives almost 80% of its total inflow. In addition, numerous rivers, tributaries and streams flow into it. The average water inflow is 114 km3 regardless of the sources. About 16 km3 comes from tributaries, and 98 km3 comes from precipitation. Annual evaporation from the surface reaches 93 km3. It is believed that over all the years of observations, the amount of water evaporating per year remains practically unchanged. The average amplitude of the 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 decreased, 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 level of the lake reached its lowest level in 80 years, it is almost one meter lower than in 1990. Measurements of the lake's water level have been carried out since 1896. The height of its level was noted in 1906 and 1917, but it remains relatively stable until 1961 of the year.

Rice. Lake Victoria as seen from space

Rice. Lake Victoria and the Great Rift Valley

The relic lakes of Africa are Chad, Tumba, Mai-Ndombe, Ngami. The largest of the relict lakes on the mainland 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 from the language of the local population is translated 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 the rivers flowing (the main Shari River). 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 negligible (4-11 m). The uniqueness of the lake lies in the fact that the upper layers of the lake are fresh, and the lower ones are salty. This is explained by the fact that salty waters are heavy for fresh ones and sink down. In addition, Chad has an underground runoff along the dry channel of the Bahr el-Ghazal to the Bodele basin, so its waters become saline. In 2006, the lake with an area of 23 thousand km², located on the borders of Nigeria, Niger, Cameroon and the Republic of Chad, decreased by 26 times and continues to dry up, which became known thanks to the monitoring of the Earth, carried out by the international system "Disaster Monitoring Constellation".

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

It is known that Chad dries up for the seventh time in the last millennium. Paleontologists have established this from the remains of animals found there.

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

Projects are being developed to transfer part of the flow from the Congo basin (in particular, Ubangi), from 15 to 100 km3 per year.

Rice. satellite image Lake Chad in 2001. Blue - water surface, green - vegetation on the old bed of the lake. Above are pictures of the lake in 1973, 1987 and 1997.

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 Basin, in the northwest of the Democratic Republic of the Congo. The length is about 130 kilometers. Located on a marshy lowland. Area - 2300 sq. km. In the north, the Lotoi River flows into the lake. Like other lakes in the Congo Basin, Mai Ndombe is the remnant of a giant endorheic lake that formed about 1 million years ago. The Lukeni and Kassai rivers flow from Lake Mai-Ndombe, which then flow into the Congo.

In the deserts and semi-deserts of South Africa, peculiar 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 foams is covered with herbaceous vegetation or bare and is composed of lake sediments 2-3 m thick. The foams are rarely filled with water, only during heavy rains. The largest of the penins - Etosha is located in the northwest 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 end of the rains it quickly turns into a swamp.

lake africa geographical

Rice. Peni Etosha

The largest of the mainland's volcanic lakes is Lake Tana, which is dammed with lava flows in the Ethiopian Highlands. The area of the lake ranges from 3.1 to 3.6 thousand km2. There are many islands in the lake. Many rivers flow into the lake, one flows out - the Blue Nile. The lake is rich in fish. Height above sea level 1830 meters. The lake is fed by four permanent rivers and numerous seasonal tributaries. The average depth is 8 meters, but during the dry and wet periods it differs by almost two meters. Depending on the season, the surface area of the lake varies from 3,000 to 3,500 square kilometers.

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

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Lake Victoria

It occupies a huge space. In terms of size, it is quite comparable to the area of an entire state, for example, Ireland. The coastline of the reservoir serves as the border for several African states at the same time: Uganda, Kenya and Tanzania.

The total area is estimated at 68 thousand km 2. The length of the water surface is 320 km, and the maximum width is 275 km. Victoria belongs to one of the deepest lakes in the world. Its maximum depth is 80 m. Its contribution to the replenishment of the reservoir fresh water contributes full-flowing Kagera. Victoria, in turn, gives rise to the Victoria Nile.

The lake is currently a reservoir. It received this status after the construction of the Owen Falls Dam in 1954, which blocked the Victoria Nile River. As a result of such actions, the natural water level rose by 3 m.

Numerous islands that are scattered throughout the water surface are home to a huge variety of birds. The waters of the lake are simply teeming with crocodiles. The area around Victoria is home to many nature reserves and national parks Africa.

Lake Tanganyika

Tanganyika is not only the largest, but also the most of Africa. The maximum water depth in this reservoir reaches 1432 kilometers, which is only slightly inferior to the famous Baikal. The lake is 650 kilometers long and 80 kilometers wide.

The shores of Tanganyika serve as a border to four countries at once: Burundi, Tanzania, Congo and Zambia. Replenishment of the water reserve of the lake is due to several rivers flowing into it. But Tanganyika serves as the source only for the Lukuga River.

Lake Tanganyika is fairly populated. Hippos live here, there are crocodiles. Many birds have chosen it as their permanent habitat. There are many varieties of fish in the waters.

Lake Malawi (Nyasa)

Lake Nyasa or Malawi is quite long and narrow when viewed from above. But this does not prevent him from taking the second place of honor in the list. deepest lakes Africa. The shores of Malawi serve as a border area for three African states: Malawi, Mozambique and Tanzania. The waters of this lake are very rich in fish: there are tilapia, campango and others. Therefore, along its banks there are a lot of fishing villages. Fishing is the most important component of the local economy.

Part of the coast of the lake, belonging to Malawi, has a fairly developed tourism infrastructure. clear waters Nyasa is absolutely safe for sailing, they will appeal to fans of snorkeling and water skiing.

These were the largest lakes in Africa belonging to the network of the Great African Lakes. Then you will get acquainted with other well-known, but much smaller reservoirs of this continent.

Lake Albert

It is located in the eastern part of Africa, on the border of two and Uganda. The total area reaches 5600 square kilometers. The coastline of the reservoir has a small number of bays, the coast for the most part is quite steep.

Lake Albert has a fairly large number of tributaries, but they only carry water during the rainy season. Of the many rivers flowing into it, only two are large: the Victoria Nile and the Semliki. At their confluence, they form huge deltas, which serve as an excellent habitat for many crocodiles and hippos. feel completely safe here. The lake serves as the source for the Albert Nile.

There are quite a lot of fish species in the reservoir (more than 40). This is a tiger fish, and many others. The shipping industry is also quite developed. The main ports are the port of Butiama, which belongs to Uganda, and Kasenyi, the main port of the Republic of the Congo.

The coast of the island, which belongs to Uganda, has a well-developed tourist infrastructure: various excursions are held here, horseback riding is offered.

Lake Edward

It is located in the central part of Africa, just a few kilometers from the equatorial line. It is a border area for two countries: Uganda and the Republic of the Congo.

It received such an unusually sonorous name in honor of the eldest son of the royal family, Edward VII.

There is one rather non-standard circumstance that makes this lake very unusual. This is one of the extremely small number of reservoirs where there are absolutely no crocodiles. These toothy monsters inhabit Lake Albert and the lower reaches of the Semliki in abundance, but for unknown reasons they do not come here.

The largest lakes in Africa

The list is headed by Lake Victoria, which has a total area of just over 68,000 km2. In second place among the largest lakes on the continent is Lake Tanganyika. The area of this reservoir occupies 34,000 km 2. The top three is closed by Lake Nyasa (Malawi). Its surface is almost 30,000 km2.

But these are not all the lakes of Africa, which are among its largest water bodies.

Lake Chad

This is the fourth largest African lake. The area of this reservoir is 27,000 km 2, but this value is not constant. During the rainy season, it can increase to 50,000 km 2, and during the dry season, decrease up to 11,000 km 2.

The lake does not have a natural runoff, so the water simply evaporates or goes into the sandy ground. In the conditions of the incredibly hot climate of the continent, with such a water regime, the water in the lake simply must be salty. But Chad - almost completely Its upper layers of water are suitable for drinking, only at the very bottom it is slightly brackish. But why don't the water layers mix? The answer is pretty simple. To the northeast of the lake there is the Bodele Basin, which is below its level. The body of water is connected to it underground river, through which the bottom salt waters leave.

Chad is home to many birds. Pelicans and flamingos come here for the winter. Many animals live on its banks. These are zebras, and giraffes, and antelopes. The list can be very long. Here you can meet the indigenous sea animal - the manatee. It still remains a mystery how he could end up in this fresh lake.

These are the most big lakes Africa. Other reservoirs have much smaller areas.

The process of formation of the Great Lakes

And they appeared as a result of the so-called Great Rifts. The bed for most of these reservoirs is the rift depression. The Great Lakes began to fill with water almost immediately after their formation.

Rift lakes can be small or large, shallow or, on the contrary, have fairly solid depths, but the only thing that unites them is their outlines. All lakes formed in this way have a specific elongated shape, which is determined by the outlines of the rifts.

African lakes. The largest lakes in Africa

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