Mouth of the Okavango River. Okavango - a river going nowhere

Seasonal rivers drying up in Africa or in deserts on other continents will not surprise anyone, but this is a special case. In all respects, the Okavango is not an oued, but a normal river that does not even think of drying up during the dry season. It quickly rushes along a narrow rapids channel with the savannah-covered banks of the Angolan plateau of Bie down in a south-easterly direction; Before the border with Botswana, it overcomes the waterfalls that form a cascade of Popa waterfalls, blocking its entire width, which in this place is 1.2 km. Only on the plateau does the river acquire a flat character.
As the slope decreases, the Okavango slows down and spreads out, spreading through a labyrinth of branches, lagoons and lakes that form the world's largest inland delta. The Okavango has a solid annual flow at the mouth; about 10 thousand km 3 of water flows into the delta annually, but... The river’s path usually ends at this gigantic delta. The Okavango does not flow into a lake, nor into another river, nor into the sea, nor into the ocean. “Where does all this water go? It’s just some kind of mysticism!” - exclaimed one of its researchers in the 19th century. In fact, where?
During high water, the southern branch of the delta feeds the freshwater Lake Ngami, the northern branch periodically, once every few years, reaches the Kwando River, a tributary - and then the Okavango briefly finds a way out into Indian Ocean. And the Botletle sleeve occasionally feeds salt Lake Tskau on the southern edge of the swamps, formed during the rainy season on the salt marshes of the Makgadikgadi drainage basin. But this is no more than 5% of all water entering the delta.
The Okavango was once part of a large river system of the ancient Lake Makgadikgadi, which supposedly had an area of 80 thousand km 2 and a depth of 30 m, but gradually dried up about 10 thousand years ago.
The residual reservoirs of the Okavango Delta are almost all that remains of the huge lake. Now in its basin during the dry season there are huge lifeless salt marshes with a cracked salt crust (very large reserves of potash), and during the rainy season two large salt lakes are formed in the depressions and life is in full swing there: animals come, birds fly in, in some places the shores seem pink from thousands of flamingos. Rarely, once every 10-15 years, these lake-swamps are connected to the Okavango Swamp through one of the branches of the Botletle delta during the rainy season.
Recent studies have shown that from total mass Of the water that annually enters the shallow, flat marshy Okavango delta, about 60% is absorbed by plants (thickets of papyrus and shrubs, algae, water lilies, lilies, etc.) and 36% evaporates from the water surface. Approximately 2% goes into the ground, and another 2% feeds Lake Ngami in high-water years. But this is not enough for the “blue heart” of the northern edge of the Kalahari Desert, and Ngami gradually dries up, gradually decreasing in size and turning from a fresh lake into a soda brine sump, with stripes of shallows and white shores.
And the Okavango Delta, which occupies an area of about 15 thousand km 2, and after the summer rains during the flood, all 22 thousand km 2, is not going to dry out and provides shelter for many birds and animals. In the northeastern part of the delta it is organized large nature reserve wildlife Moremi (Botswana).
In the upper reaches, the Okavango River (Cubango) flows from the Bie plateau onto the plain - fast, narrow and rapids. Then it acquires a flat character and flows calmly, but before the border with Botswana its channel along the entire width of 1.2 km is crossed by waterfalls (in the dry season they protrude above the water), forming Popa Falls. After them, the river’s edge drops by 4 m. In the lower reaches, the river gradually slows down as it approaches the northern edge of the Kalahari Desert.
The shallow, swampy and flat (elevation differences of less than 2 m) river delta, also known as the Okavango Swamp, forms an oasis with richest variety flora and fauna. This is where the path of the water flow usually ends.
On a map of northwestern Botswana, the inner Okavango delta, with its central swampy area and branches, resembles the shape of an open palm extended towards the Kalahari.
The Okavango is the only permanent river of the vast Kalahari plain, located between the Zambezi rivers, and South Africa. On maps it is usually designated as the “Kalahari Desert”. But these places are not like the Sahara or the deserts of Arabia; Compared to them, it is not even quite a desert. In summer, the Kalahari experiences heavy rainfall, ranging from 250 mm in the south to 1000 mm in the north of precipitation per year. In addition to one permanent river, there are also temporary rivers and lakes (most of which, however, dry up in winter). Trees, shrubs and herbs grow in the Kalahari, and in large quantities. Therefore, scientists cannot agree on what is more correct to call it: “desert savanna”, “green semi-desert” or, perhaps, “steppe park landscape”. Sometimes on maps its central sandy region is distinguished as the “Kalahari Desert”, and its outskirts as the “Kalahari Basin”. And the vast green wetlands of the shallow, flat Okavango Delta amid the sands of the northwestern sector of the Kalahari Desert are called the world's largest oasis. In terms of its importance for southwest Africa, the Okavango is no less important than the Nile for the northeast. The life of all inhabitants of the surrounding area directly depends on their waters.
Okavango Swamps all year round teeming with all kinds of living creatures. Here, in this giant green oasis, overgrown with reeds, bushes, water lilies and algae, elephants, giraffes and antelopes, lions, leopards and hyenas and many others come from afar to drink. It is a paradise for waterfowl, hippos and all kinds of insects...
Archaeological finds confirm that people have continuously lived in the lower reaches of the Okavango for 30 thousand years, but there have always been few of them: perhaps precisely because of insects that carry malaria, sleeping sickness and other tropical ailments. Nowadays, the banks of the river are mainly inhabited by Bantu peoples, including those who gave the river its name, the Kavango. Also living here are the indigenous peoples of hunters and gatherers - the Bushmen ( common name), who inhabited South Africa long before the Bantu migration. The Tsodilo Hills, west of the Okavango Delta, are a sacred place for the Bushmen and their ancestors, with many legends associated with this place and the firm belief that the ancient gods still live in caves painted by their ancestors with thousands of Stone Age rock paintings.
The Okavango in its upper, middle and lower reaches is divided between Angola, Namibia and Botswana. Moreover, they are dividing in the literal sense, seriously conflicting over water and river resources that are precious in arid areas (these territories suffer from drought). Although there is practically no economic activity directly along the banks of the river (due to which, by the way, the water in the river is very clean), Angola and Namibia are trying to save the situation of existing farms: the first - through the construction of a dam, the second - through the already built water diversion canal and the planned pipeline construction. Botswana has a delta famous for its rich wildlife, and ecotourism in the Moremi Game Reserve and safari activities contribute greatly to the state treasury, so why lose such important source The local government does not intend to generate income due to the threat of water shortage and, as a result, impoverishment of flora and fauna. Therefore, now controversial issues regarding water consumption between neighboring countries are resolved by a special commission.

general information

A river flowing inland and flowing into the Kalahari Desert.

Location: southwest Africa, flowing from the Bie plateau in Angola to the southeast, ending in a vast marshy delta on the northern edge of the Kalahari Desert.

Feeding method: mainly rain.

Basin: an area of internal drainage that does not empty into any ocean.
Source height: 1780 m above sea level (Bie plateau).

Estuary: Okavango swamps (700-1000 m above sea level), formerly Lake Makgadikgadi (dry).

Other names: Cubango (in Angola).

Largest influx: Quito (left).
Flows through the territory: the upper course in Angola, 400 km to the south serves as a natural border between Angola and Namibia, then flows through the territory of Botswana.

Numbers

Length: 1600 km - 4th longest in South Africa.
Width: narrow in the upper reaches, up to 20 km closer to the delta.
Pool area: 721,258 km 2 .

Delta area: about 15,000 km2 (up to 22,000 km2 during the rainy season) - the largest inland delta in the world.

Average water consumption: 475 m 3 /s.

Water flow at the mouth by season: 100-200 m 3 /s in the dry season (November), about 1000 m 3 /s in the rainy season (March and April).

Annual flow: about 10,000 km3.

Solid runoff: about 2 million tons per year of solid sediments (sand, etc.) and another 2 million tons per year of dissolved salts settling in the delta during the evaporation of moisture.

Water level: drops by 4 m after Popa Falls (before the border with Botswana).

Climate and weather

The Okavango Delta is a kind of oasis with a special microclimate, very different from the surrounding tropical arid climate.

Hot and wet season rains: December - March (humidity 50-80%, up to 40°C during the day, warm nights).

The most comfortable period: March - early June (about 30°C during the day, cool nights).
Dry and cold season: June - August (warm during the day, night temperatures can drop to 0°C).

Dry and hot season: September - November.

Average annual precipitation: 450 mm.

Economy

The banks of the river are sparsely populated; There is virtually no agricultural or industrial activity along the Okavango, so the water is very clean.

Agriculture: subsistence farming, hunting and gathering; livestock farming in dry areas on the outskirts of the delta.

Fishery.
Service sector: tourism (safari and ecotourism).

Attractions

■ Natural: gorges and rapids in the upper reaches, Popa waterfalls (to the border of Botswana), Okavango delta (swamp) overgrown with reeds and water lilies; Lake Ngami with acacia, baobabs and palm trees along the banks, the ancient dry lake Makgadikgadi.
■ National Park Moremi(with an area of 3900 km 2, located in the north-eastern part of the Okavango River Delta): the park does not have any fences, animals move freely throughout the reserve and beyond; many come here from afar to drink water during the dry season, such as elephants from the neighboring Chobe Nature Reserve. Among the animals in Moremi Park you can find zebras, elephants, giraffes, buffalos, baboons, hippos, crocodiles, many different antelopes (impala, kudu, bushbuck, springbok, waterbuck, puku and wildebeest); Among the predators there are lions, leopards, cheetahs, hyenas and jackals. More than 400 species of birds (hoopoes, herons, ibises, etc.).
■ Makgadikgadi National Park(4900 km 2, located in the basin of the same name, an ancient lake that dried up about 10,000 years ago. During the rainy season, low-lying areas are filled with water and turn into a swamp, people come here wild animals and thousands and thousands of birds flock (especially many pink flamingos).
■ Cultural-historical: The Tsodilo Hills, sacred to the Bushmen, west of the Okavango Delta - thousands of Stone Age rock paintings have been discovered in the caves there.

Curious facts

■ Most of the salt islands in the Okavango Delta were formed on the site of termite mounds.
■ The surface of the delta is almost flat, the elevation changes are only about 2 m, and the flow there is extremely slow: it takes approximately seven months for river water to reach the southern edge of the delta from the top of the delta.
■ To protect the river delta from poaching and industrial livestock farming, the Botswana government decided to develop tourism. But permission to visit these protected places Only 4,000 people a year can receive it, and it is very, very expensive.
■ Botswana is a leader in diamond mining, but this does not save the majority of the population from hunger. After emergency, which developed in the late 1970s as a result of drought and a foot-and-mouth epidemic among livestock, it was decided to expand grazing resources by fencing off the outlying areas of the Okavango Delta in order to be able to graze livestock in dry areas of the swamp.

This amazing river flows into amazing place and ends in a surprising way. Surprising with its number and diversity and animal world its shores.

No less surprising is the unique language of the people living in its basin.

The Okavango is the only permanent river in a vast and unusual area called the Kalahari, located between the Zambezi, Limpopo and Orange rivers in South Africa.

It is customary to write “Kalahari Desert” on maps. But this is not a desert at all.

In summer it rains heavily here, and in terms of annual precipitation (from a thousand millimeters in the north to two hundred and fifty in the south), these places cannot be compared, for example, with the Sahara or the deserts of Arabia.

Scientists have not been able to agree on what the Kalahari is. Some call it “desert savannah”, others use the term “green semi-desert”, others believe that in relation to such places it is more appropriate to talk about steppe park landscapes.

One way or another, there is water in the Kalahari. There are temporary rivers (during the rainy season), and lakes (most of which, however, dry up in winter). There are trees, shrubs, and herbs here, and in large quantities.

Umbrella acacias and tree-like spurges grow in the Kalahari forty to fifty meters from each other, as befits savanna trees.

Bushes and grass (sometimes up to a meter high) also do not cover the ground with a continuous carpet; Islands of sand are always visible between the green patches of vegetation. But this vegetation is quite enough for thousands of herds of antelope, buffalo and zebra for food, especially since the Okavango, this South African Nile, provides them with water all year round.

Beginning in the savannas of southern Angola, this river quickly rushes south through gorges and rapids, along steep slopes with waterfalls. And only in the Kalahari does it calm down, as if forgetting about its violent temper.

In the endless sea of sandy plain, it spreads through labyrinths of branches, lagoons, lakes, forming a completely unusual river delta at the confluence... into nowhere.

It is called "an island of water in a sea of sand."

Sixteen square kilometers of thickets of papyrus, bushes and algae provide shelter to many birds and animals all year round.

And during the flood, in May-June, the half-dried branches of the delta turn into stormy foaming streams, one of which reaches the “blue heart of the Kalahari” - the beautiful and inhabited freshwater Lake Ngami, opened to science by the great Livingstone.

The remnants of the Okavango waters wander for another three hundred kilometers and disappear into the huge lake-swamp Makarikari.

The lake is a giant settling tank for soda brine.

In the dry season, from an airplane it resembles a lunar landscape: a solid white blanket with rare dark spots of water stretches all the way to the horizon.

The winding stripes of shallows surrounded by a motionless sultry haze are clearly visible.

The Okavango Delta contains all (or almost all) species of African fauna. Hippos coexist with crocodiles on green islands.

Herds of graceful antelopes rush by. Looking around carefully, a timid water goat gallops by - sensing danger, it plunges into the water up to its nostrils.

Graceful giraffes and gloomy buffalos and wildebeest come to drink.

Slowly, with a sense of self-esteem, elephants and rhinoceroses walk towards the water, and shaggy and serious warthogs dart busily through the thickets.

Not far away, zebras, eland antelopes and ostriches graze in a friendly company - together it is easier for them to detect predators, since the birds' vision complements the sensitive hearing of striped horses and the delicate sense of smell of antelopes.

And, of course, around this abundance of game there are leopards, cheetahs and royal lions with their constant retinue of hyenas and jackals, and gloomy vultures slowly circle in the air, looking out for prey.

The abundance of fauna in the Okavango Delta is amazing. In addition to the animals already mentioned, there are about four hundred species of birds and up to seventy species of fish.

And the flora of the delta numbers more than a thousand trees and shrubs.

And a traveler going to this unique oasis on a local pirogue - mokoro, will be able, during such a unique water safari, to see and capture on film water antelopes and hyena dogs, which have almost disappeared in other parts of Africa, admire herds of elephants, zebras and blue wildebeests, or catch a fishing rod of a hefty bream, or even a tiger fish.

And from the shores and islands, flocks of pelicans and storks, flamingos and marabou will look at the floating pirogue...

When the heat gives way to coolness and an impenetrable tropical night thickens over the Kalahari, the inhabitants of these places - Tswana shepherds and Bushmen hunters - find their way along the stars, so bright in these latitudes.

Their main reference point is the southern tropical constellation Capricorn. They turn to him with requests, and they thank him for a successful hunt.

Bushmen - mysterious people. In appearance they do not resemble the majority of South Africans. Yellow skin and narrowed eyes bring them closer to peoples Mongoloid race. How and why they ended up in the depths of the “Dark Continent”, science does not yet know.

The language of the Bushmen puzzled (and still puzzles!) even linguistic experts. A European cannot not only pronounce half of its sounds, but even write them down. The compilers of dictionaries did not have icons to indicate such sounds, and they simply wrote down: “clicking sound,” “smacking sound,” “kissing sound,” and so on.

The Bushmen are nomadic hunters, and the Kalahari, which in the 19th century was considered one of the richest regions in Africa, gave them the opportunity to feed their families with tasty game, as well as the edible roots and juicy fruits of wild melon.

But the appearance of white people with firearms quickly led to a reduction in the number of wild animals, and moreover, more and more watering places began to be captured by the neighboring tribes of Tswana pastoralists, pushing the Bushmen into the driest areas.

However, this intelligent people of born hunters and trackers managed to adapt to new conditions and now roam further south, closer to the basin of the Orange River and its tributaries that dry up in winter.

The ability to find places in dry riverbeds where there may be water under the sand helps them out, allowing them to survive until the rainy season, and the ability to eat everything that moves on the grass or sand, from larvae to locusts, allows them to survive in the event of an unsuccessful hunt.

This amazing tribe evokes involuntary sympathy with its intelligence, musicality, humor and kindness, which, by the way, was demonstrated by the recently released talented film “The gods must have gone crazy...”.

The Okavango crosses from northwest to southeast almost half of the vast southern African country of Botswana, which lies entirely in the Kalahari.

Until recently, this poor pastoral state did not shine with economic success.

But since the 1960s of the 20th century, when several large diamond deposits were discovered in the depths of Botswana, the situation has changed.

Now the country can afford to drill water wells in the dry park forests of the Kalahari, build civilized villages for the Bushmen and Tswana, and, finally, take up the protection of wildlife.

National parks and reserves now occupy almost a fifth of Botswana. They are found in the north, in the Zambezi basin, and in the southwest - on the tributaries of the Orange River.

But the three largest reserves cover the Central Kalahari, Okavango Delta and Lake Makarikari.

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Okavango (Cubango)

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