The Zambezi (also spelled Zambeze and Zambesi) is the fourth-longest river in Africa, the longest east-flowing river in Africa and the largest flowing into the Indian Ocean from Africa. Its drainage basin covers , slightly less than half of the Nile's. The river rises in Zambia and flows through eastern Angola, along the north-eastern border of Namibia and the northern border of Botswana, then along the border between Zambia and Zimbabwe to Mozambique, where it crosses the country to empty into the Indian Ocean.
The Zambezi's most noted feature is Victoria Falls. Its other falls include the Chavuma Falls at the border between Zambia and Angola and Ngonye Falls near Sioma in western Zambia.
The two main sources of Hydroelectricity power on the river are the Kariba Dam, which provides power to Zambia and Zimbabwe, and the Cahora Bassa Dam in Mozambique, which provides power to Mozambique and South Africa. Additionally, two smaller power stations are along the Zambezi River in Zambia, one at Victoria Falls and the other in Zengamina, near Kalene Hill in the Ikelenge District.
Eastward of the source, the watershed between the Congo Basin and is a well-marked belt of high ground, running nearly east–west and falling abruptly to the north and south. This distinctly cuts off the basin of the Lualaba River (the main branch of the upper Congo) from the Zambezi. In the neighborhood of the source, the watershed is not as clearly defined, but the two river systems do not connect.Dorling Kindersley, pp. 84–85
The region drained by the Zambezi is a vast, broken-edged plateau 900–1,200 m high, composed in the remote interior of metamorphic rock beds and fringed with the of the Victoria Falls. At Chupanga, on the lower Zambezi, thin strata of grey and yellow , with an occasional band of limestone, crop out on the bed of the river in the dry season, and these persist beyond Tete, where they are associated with extensive seams of coal. Coal is also found in the district just below Victoria Falls. Gold-bearing rocks occur in several places.
The first of its large tributaries to enter the Zambezi is the Kabompo River in the North-Western Province of Zambia. The savanna through which the river flows gives way to a wide floodplain, studded with Borassus . A little farther south is the confluence with the Lungwebungu River. This is the beginning of the Barotse Floodplain, the most notable feature of the upper Zambezi, but this northern part does not flood so much and includes islands of higher land in the middle.
About 30 km below the confluence of the Lungwebungu, the country becomes very flat, and the typical Barotse Floodplain landscape unfolds, with the flood reaching a width of 25 km in the rainy season. For more than 200 km downstream, the annual flood cycle dominates the natural environment and human life, society, and culture. About 80 km further down, the Luanginga River, which with its tributaries drains a large area to the west, joins the Zambezi. A short distance higher up on the east, the main stream is joined in the rainy season by overflow of the Luampa River/Luena system.
A short distance downstream of the confluence with the Luanginga is Lealui, one of the capitals of the Lozi people, who populate the Zambian region of Barotseland in the Western Province. The chief of the Lozi maintains one of his two compounds at Lealui; the other is at Limulunga, which is on high ground and serves as the capital during the rainy season. The annual move from Lealui to Limulunga is a major event, celebrated as one of Zambia's best-known festivals, the Kuomboka.
After Lealui, the river turns south-southeast. From the east, it continues to receive numerous small streams, but on the west, it is without major tributaries for 240 km. Before this, the Ngonye Falls and subsequent rapids interrupt navigation. South of Ngonye Falls, the river briefly borders Namibia's Caprivi Strip. Below the junction of the Cuando River and the Zambezi, the river bends almost due east. Here, the river is broad and shallow and flows slowly, but as it flows eastward towards the border of the great central plateau of Africa, it reaches a chasm into which the Victoria Falls plunge.
At this point, the river enters Lake Kariba, created in 1959 following the completion of the Kariba Dam. The lake is one of the largest man-made lakes in the world, and the hydroelectric power-generating facilities at the dam provide electricity to much of Zambia and Zimbabwe.
The Luangwa River and Kafue River rivers are the two largest left-hand tributaries of the Zambezi. The Kafue joins the main river in a quiet, deep stream about wide. From this point, the northward bend of the Zambezi is checked, and the stream continues due east. At the confluence of the Luangwa (15°37' S), it enters Mozambique.
The middle Zambezi ends where the river enters Lake Cahora Bassa, formerly the site of dangerous rapids known as Kebrabassa; the lake was created in 1974 by the construction of the Cahora Bassa Dam.
About from the sea, the Zambezi receives the drainage of Lake Malawi through the Shire River. On approaching the Indian Ocean, the river splits up into a River delta. Each of the primary distributaries, Kongone, Luabo, and Timbwe, is obstructed by a Shoal. A more northerly branch, called the Chinde River mouth, has a minimum depth at low water of at the entrance and further in, and is the branch used for navigation. About further north is a river called the Quelimane, after the town at its mouth. This stream, which is silting up, receives the overflow of the Zambezi in the rainy season.
The discharges of these systems contribute to a much larger flood in March or April, with a mean monthly maximum for April of per second at the delta. The record flood was more than three times as big, per second being recorded in 1958. By contrast, the discharge at the end of the dry season averaged just per second.
In the 1960s and 1970s, the building of dams changed that pattern completely. Downstream, the mean monthly minimum–maximum was per second; now it is per second. Medium-level floods especially, of the kind to which the ecology of the lower Zambezi was adapted, happen less often and have a shorter duration. As with the Itezhi-Tezhi Dam's deleterious effects on the Kafue Flats, this has these effects:
Although the dams have stemmed some of the annual flooding of the lower Zambezi and caused the area of floodplain to be greatly reduced, they have not removed flooding completely. They cannot control extreme floods, and they have only made medium-level floods less frequent. When heavy rain in the lower Zambezi combines with significant runoff upstream, massive floods still happen, and the wetlands are still an important habitat. The shrinking of the wetlands, though, resulted in uncontrolled hunting of animals such as African buffalo and waterbuck during the Mozambican Civil War.
Although the region has had a reduction in the populations of the large mammals, it is still home to some, including the reedbuck and migrating common eland. Carnivores found here include lion ( Panthera leo), leopard ( Panthera pardus), cheetah ( Acinonyx jubatus), spotted hyena ( Crocuta crocuta), and side-striped jackal ( Canis adustus). The floodplains are a haven for migratory waterbirds, including northern pintail, garganey, African openbill ( Anastomus lamelligerus), saddle-billed stork ( Ephippiorhynchus senegalensis), wattled crane ( Bugeranus carunculatus), and great white pelican ( Pelecanus onocrotalus).
Reptiles include Nile crocodile ( Crocodylus niloticus), Nile monitor lizard ( Varanus niloticus), Python sebae ( Python sebae), the endemic Pungwe worm snake ( Leptotyphlops pungwensis), and three other snakes that are nearly endemic - floodplain water snake ( Lycodonomorphus whytei obscuriventris), dwarf wolf snake ( Lycophidion nanus), and swamp viper ( Proatheris).
Several butterfly species are endemic.
The Zambezi also supports several hundred species of fish, some of which are endemic to the river. Important species include , which are fished heavily for food, as well as catfish, tigerfish, yellowfish, and other large species. The bull shark is sometimes known as the Zambezi shark after the river, not to be mistaken with River shark freshwater shark genus that inhabit the river, as well.
Middle Zambezi cumulatively 1,050,000 km2, 2442 m3/s, measured at Cahora Bassa Gorge
Lower Zambezi cumulatively, 1,378,000 km2, 3424 m3/s, measured at Marromeu
Total Zambezi Basin: 1,390,000 km2, 3424 m3/s discharged into delta
Source: Beilfuss & Dos Santos (2001) The Kalahari Basin is not included in the figures because it only occasionally overflows to any extent into the Zambezi.
Because of the rainfall distribution, northern tributaries contribute much more water than southern ones; for example: The Northern Highlands catchment of the upper Zambezi contributes 25%, Kafue 8%, Luangwa and Shire Rivers 16% each, total 65% of Zambezi discharge. The large Cuando basin in the south-west, though, contributes only about 2 m3/s because most is lost through evaporation in its swamp systems. The 1940s and 1950s were particularly wet decades in the basin. Since 1975, it has been drier, the average discharge being only 70% of that for the years 1930 to 1958.
Meanwhile, east, a western tributary of the Shire River in the East African Rift's southern extension through Malawi eroded a deep valley on its western escarpment. At a slow rate, the middle Zambezi started cutting back the bed of its river towards the west, aided by () forming along its course in an east–west axis. As it did so, it Stream capture several south-flowing rivers such as the Luangwa and Kafue.
Eventually, the large lake trapped at Makgadikgadi (or a tributary of it) was captured by the middle Zambezi cutting back towards it, and emptied eastwards. The upper Zambezi was captured, as well. The middle Zambezi was about lower than the upper Zambezi, and a high waterfall formed at the edge of the basalt plateau across which the upper river flows. This was the first Victoria Falls, somewhere down the Batoka Gorge near where Lake Kariba is now. AWF Four Corners Biodiversity Information Package No 2: Summary of Technical Reviews Accessed 1 March 2007.
In 1552, Portuguese chronicler João de Barros noted that the same Cuama River was called Zembere by the inland people of Monomatapa.Barros, Da Asia, Dec. I, Lib. X, vol. 2, p.374) The Portuguese Dominican friar João dos Santos, visiting Monomatapa in 1597 reported it as Zambeze (Bantu languages frequently shifts between z and r) and inquired into the origins of the name; he was told it was named after a people.
Thus, the term "Zambezi" is after a people who live by a great lake to the north. The most likely candidates are the "M'biza", or Bisa people (in older texts given as Muisa, Movisa, Abisa, Ambios, and other variations), a Bantu people who live in what is now central-eastern Zambia, between the Zambezi River and Lake Bangweulu (at the time, before the Lunda invasion, the Bisa would have likely stretched further north, possibly to Lake Tanganyika). The Bisa had a reputation as great cloth traders throughout the region.The connection between Santos/Monomatapa "Zambezi" and the "M'biza" is suggested in Cooley (1845).
In a curious note, Goese-born Portuguese trader Manuel Caetano Pereira, who traveled to the Bisa homelands in 1796, was surprised to be shown a second, separate river referred to as the "Zambezi"."Notícias dadas por Manoel Caetano Pereira, comerciante, que se entranhou pelo interior da África", as published in José Acúrsio das Neves (1830) Considerações Políticas e Comerciais sobre os Descobrimentos e Possessões na África e na Ásia. Lisbon: Imprensa Regia. p.373 This "other Zambezi" that puzzled Pereira is most likely what modern sources spell the Chambeshi River in northern Zambia.
The Monomatapa notion (reported by Santos) that the Zambezi was sourced from a great internal lake might be a reference to one of the African Great Lakes. One of the names reported by early explorers for Lake Malawi was "Lake Zambre" (probably a corruption of "Zambezi"), possibly because Lake Malawi is connected to the lower Zambezi via the Shire River. The Monomatapa story resonated with the old European notion, drawn from classical antiquity, that all the great African rivers—the Nile, the Senegal River, the Congo, and the Zambezi—were all sourced from the same great internal lake. The Portuguese were also told that the Mozambican Espirito Santo "river" (actually an estuary formed by the Umbeluzi, Matola River, and Tembe River Rivers) was sourced from a lake (hence its outlet became known as Maputo Bay). As a result, several old maps depict the Zambezi and the "Espirito Santo" Rivers converging deep in the interior, at the same lake.
However, the Bisa-derived etymology is not without dispute. In 1845, W.D. Cooley, examining Pereira's notes, concluded the term "Zambezi" derives not from the Bisa people, but rather from the Bantu term "mbege"/"mbeze" ("fish"), and consequently it probably means merely "river of fish".W.D. Cooley (1845) "The Geography of N'yassi, or the Great Lake of Southern Africa, investigated, with an account of the overland route from the Quanza in Angola to the Zambezi in the government of Mozambique", Journal of the Royal Geographical Society, p.185-235. David Livingstone, who reached the upper Zambezi in 1853, refers to it as "Zambesi", but also makes note of the local name "Leeambye" used by the Lozi people, which he says means "large river or river par excellence". Livingstone records other names for the Zambezi—Luambeji, Luambesi, Ambezi, Ojimbesi, and Zambesi—applied by different peoples along its course, and asserts they "all possess a similar signification and express the native idea of this magnificent stream being the main drain of the country".David Livingstone (1857) Missionary Travels and Researches in South Africa ( p.208)
Other historical records show that the river was called Kasambabezi by the Tonga people, which means "only those who know the river can bath in it." a name which is still in use to this day.
In Portuguese records, the "Cuama River" term disappeared and gave way to the term "Sena River" ( Rio de Sena), a reference to the Swahili (and later Portuguese) upriver trade station at Sena. In 1752, the Zambezi Delta, under the name "Rivers of Sena" ( Rios de Sena) formed a colonial administrative district of Portuguese Mozambique, but common usage of "Zambezi" led eventually to a royal decree in 1858 officially renaming the district "Zambézia".
The first European to visit the inland Zambezi River was the Portuguese degredado António Fernandes in 1511 and again in 1513, with the objective of reporting on commercial conditions and activities of the interior of Central Africa. The final report of these explorations revealed the importance of the ports of the upper Zambezi to the local trade system, in particular to East African gold trade.
The first recorded exploration of the upper Zambezi was made by David Livingstone in his exploration from Bechuanaland between 1851 and 1853. Two or three years later, he descended the Zambezi to its mouth and in the course of this journey found the Victoria Falls. During 1858–60, accompanied by John Kirk, Livingstone ascended the river by the Kongone mouth as far as the falls, and also traced the course of its tributary the Shire and reached Lake Malawi.
For the next 35 years, very little exploration of the river took place. Portuguese explorer Serpa Pinto examined some of the western tributaries of the river and made measurements of the Victoria Falls in 1878. In 1884, Scottish-born Plymouth Brethren missionary Frederick Stanley Arnot traveled over the height of land between the watersheds of the Zambezi and the Congo and identified the source of the Zambezi. He considered that the nearby high and cool Kalene Hill was a particularly suitable place for a mission. Arnot was accompanied by Portuguese trader and army officer António da Silva Porto.
In 1889, the Chinde channel north of the main mouths of the river was seen. Two expeditions led by Major A. St Hill Gibbons in 1895 to 1896 and 1898 to 1900 continued the work of exploration begun by Livingstone in the upper basin and central course of the river.
Communities by the river fish it extensively, and many people travel from far afield to fish. Some Zambian towns on roads leading to the river levy unofficial "fish taxes" on people taking Zambezi fish to other parts of the country. Game fishing, as well as fishing for food, is a significant activity on some parts of the river. Between Mongu and Livingstone, several safari lodges cater to tourists who want to fish for exotic species, and many also catch fish to sell to Public aquarium.
The river valley is rich in mineral deposits and fossil fuels, and coal mining is important in places. The dams along its length also provide employment for many people near them, in maintaining the hydroelectric power stations and the dams themselves. Several parts of the river are also very popular tourist destinations. Victoria Falls receives over 100,000 visitors annually, with 141,929 visitors reported in 2015.[6] Republic of Zambia Ministry of Tourism and Arts 2015 Tourism Statistical Digest Mana Pools and Lake Kariba also draw substantial tourist numbers.
In the 1930s and 40s, a paddle-barge service operated on the stretch between the Katombora Rapids, about upstream from Livingstone, and the rapids just upstream from Katima Mulilo. Depending on the water level, boats could be paddled through—Lozi paddlers, a dozen or more in a boat, could deal with most of them—or they could be pulled along the shore or carried around the rapids, and teams of oxen pulled barges over land around the Ngonye Falls.E. C. Mills: "Overlanding Cattle from Barotse to Angola" , The Northern Rhodesia Journal, Vol 1 No 2, pp 53–63 (1950). Accessed 16 December 2017.
Road, rail, and other crossings of the river, once few and far between, are proliferating. They are, in order from the river's source:
A number of small ferries cross the river in Angola, western Zambia, and Mozambique, notably between Mongu and Kalabo. Above Mongu in years following poor rainy seasons, the river can be forded at one or two places. In tourist areas, such as Victoria Falls and Kariba Dam, short-distance tourist boats take visitors along the river.
The river currently passes through Ngonye Falls National Park, Mosi-oa-Tunya National Park, and Lower Zambezi National Park (in Zambia), and the Zambezi National Park, Victoria Falls National Park, Matusadona National Park, Mana Pools National Park, and the Middle Zambezi Biosphere Reserve (in Zimbabwe).
Namibian officials have consequently banned monofilament nets and imposed a closing period of about 3 months every year to allow the fish to breed. They also appointed village fish guards and the Kayasa Channel in the Impalila conservancy area was declared a fisheries reserve. The Namibian ministry also promotes aquaculture and plans to distribute thousands of fingerlings to registered small-scale fish farmers of the region.
Middle Zambezi
Lower Zambezi
Discharge
! rowspan="2" >Year
! colspan="3" Discharge (m3/s)
! rowspan="2" Year
! colspan="3" Discharge (m3/s) 1998 1,141 3,335 11,183 2011 17 2,619 6,117 1999 600 4,259 11,084 2012 1,383 3,522 7,553 2000 338 3,041 6,696 2013 1,243 3,877 8,622 2001 112 9,151 39,802 2014 2,394 4,161 8,946 2002 631 2,536 4,910 2015 3,307 6,095 15,826 2003 329 2,536 8,952 2016 1,754 4,418 9,124 2004 79 2,013 4,824 2017 2,133 4,686 9,215 2005 888 3,030 7,973 2018 2,177 4,988 8,802 2006 1,549 3,651 7,575 2019 2,867 5,942 12,091 2007 2,208 4,636 14,141 2020 3,001 5,131 10,031 2008 2,881 6,949 31,975 2021 2,331 5,977 10,196 2009 154 2,648 5,930 2022 868 4,953 14,361 2010 58 2,284 6,342 17 4,217 39,802
Delta
Ecology of the delta
Climate
Wildlife
Tributaries
Geological history
History
Etymology
Exploration
Economy
Transport
Ecology
Pollution
Effects of dams
Conservation measures
Fish stocks management
EUS outbreak
Major towns
See also
Further reading
External links
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