Course_of_the_river Zambezi

1 course of river

1.1 sources
1.2 upper zambezi
1.3 middle zambezi
1.4 lower zambezi
1.5 delta

1.5.1 ecology of delta

course of river
sources

the zambezi , river basin

the river rises in black marshy dambo in dense undulating miombo woodland 50 kilometres (31 mi) north of mwinilunga , 20 kilometres (12 mi) south of ikelenge in ikelenge district of north-western province, zambia @ 1,524 metres (5,000 ft) above sea level. area around source national monument, forest reserve , important bird area.

eastward of source, watershed between congo , zambezi basins well-marked belt of high ground, running east-west , falling abruptly north , south. distinctly cuts off basin of lualaba (the main branch of upper congo) of zambezi. in neighborhood of source watershed not defined, 2 river systems not connect.

the region drained zambezi vast broken-edged plateau 900–1200 m high, composed in remote interior of metamorphic beds , fringed igneous rocks of victoria falls. @ shupanga, on lower zambezi, thin strata of grey , yellow sandstones, occasional band of limestone, crop out on bed of river in dry season, , these persist beyond tete, associated extensive seams of coal. coal found in district below victoria falls. gold-bearing rocks occur in several places.

upper zambezi

the river flows south-west angola 240 kilometres (150 mi), joined sizeable tributaries such luena , chifumage flowing highlands north-west. turns south , develops floodplain, extreme width variation between dry , rainy seasons. enters dense evergreen cryptosepalum dry forest, though on western side, western zambezian grasslands occur. re-enters zambia 400 metres (1,300 ft) wide in rainy season , flows rapidly, rapids ending in chavuma falls, river flows through rocky fissure. river drops 400 metres (1,300 ft) in elevation source @ 1,500 metres (4,900 ft) chavuma falls @ 1,100 metres (3,600 ft), in distance of 400 kilometres (250 mi). point victoria falls, level of basin uniform, dropping 180 metres (590 ft) in distance of around 800 kilometres (500 mi).

the first of large tributaries enter zambezi kabompo river in north-western province of zambia. major advantage of kabompo river irrigation. civilization built on farming, , surplus of crops. savanna through river has flowed gives way wide floodplain, studded borassus fan palms. little farther south confluence lungwebungu river. beginning of barotse floodplain, notable feature of upper zambezi, northern part not flood , includes islands of higher land in middle.

thirty kilometres below confluence of lungwebungu country becomes flat, , typical barotse floodplain landscape unfolds, flood reaching width of 25 km in rainy season. more 200 km downstream annual flood cycle dominates natural environment , human life, society , culture.

eighty kilometres further down, luanginga, tributaries drains large area west, joins zambezi. few kilometres higher on east main stream joined in rainy season overflow of luampa/luena system.

a short distance downstream of confluence luanginga lealui, 1 of capitals of lozi people populate zambian region of barotseland in western province. chief of lozi maintains 1 of 2 compounds @ lealui; other @ limulunga, on high ground , serves capital during rainy season. annual move lealui limulunga major event, celebrated 1 of zambia s best known festivals, kuomboka.

after lealui, river turns south-south-east. east continues receive numerous small streams, on west without major tributaries 240 km. before this, ngonye falls , subsequent rapids interrupt navigation. south of ngonye falls, river briefly borders namibia s caprivi strip. strip projects main body of namibia, , results colonial era: added german south-west africa expressly give germany access zambezi.

below junction of cuando river , zambezi river bends due east. here, river broad , shallow, , flows slowly, flows eastward towards border of great central plateau of africa reaches chasm victoria falls plunge.

middle zambezi

victoria falls, end of upper zambezi , beginning of middle zambezi

the victoria falls considered boundary between upper , middle zambezi. below them river continues flow due east 200 kilometres (120 mi), cutting through perpendicular walls of basalt 20 60 metres (66 200 ft) apart in hills 200 250 metres (660 820 ft) high. river flows swiftly through batoka gorge, current being continually interrupted reefs. has been described 1 of world s spectacular whitewater trips, tremendous challenge kayakers , rafters alike. beyond gorge succession of rapids end 240 km (150 mi) below victoria falls. on distance, river drops 250 metres (820 ft).

at point, river enters lake kariba, created in 1959 following completion of kariba dam. lake 1 of largest man-made lakes in world, , hydroelectric power-generating facilities @ dam provide electricity of zambia , zimbabwe.

the luangwa , kafue 2 largest left-hand tributaries of zambezi. kafue joins main river in quiet deep stream 180 metres (590 ft) wide. point northward bend of zambezi checked , stream continues due east. @ confluence of luangwa (15°37 s) enters mozambique.

the middle zambezi ends river enters lake cahora bassa (also spelled cabora bassa). formerly site of dangerous rapids known kebrabassa, lake created in 1974 construction of cahora bassa dam.

lower zambezi

the lower zambezi s 650 km cahora bassa indian ocean navigable, although river shallow in many places during dry season. shallowness arises river enters broad valley , spreads out on large area. @ 1 point, lupata gorge, 320 km mouth, river confined between high hills. here scarcely 200 m wide. elsewhere 5 8 km wide, flowing gently in many streams. river bed sandy, , banks low , reed-fringed. @ places, however, , in rainy season, streams unite 1 broad fast-flowing river.

about 160 km sea zambezi receives drainage of lake malawi through shire river. on approaching indian ocean, river splits delta. each of 4 primary distributaries, kongone, luabo , timbwe, obstructed sand bar. more northerly branch, called chinde mouth, has minimum depth @ low water of 2 m @ entrance , 4 m further in, , branch used navigation. 100 km further north river called quelimane, after town @ mouth. stream, silting up, receives overflow of zambezi in rainy season.

delta

the delta of zambezi today half broad before construction of kariba , cahora bassa dams controlled seasonal variations in flow rate of river.

before dams built seasonal flooding of zambezi had quite different impact on ecosystems of delta today brought nutritious fresh water down indian ocean coastal wetlands. lower zambezi experienced small flood surge in dry season rain in gwembe catchment , north-eastern zimbabwe rushed through while rain in upper zambezi, kafue, , lake malawi basins, , luangwa lesser extent, held swamps , floodplains. discharge of these systems contributed larger flood in march or april, mean monthly maximum april of 6,700 cubic metres (240,000 cu ft) per second @ delta. record flood more 3 times big, 22,500 cubic metres (790,000 cu ft) per second being recorded in 1958. contrast discharge @ end of dry season averaged 500 cubic metres (18,000 cu ft) per second.

in 1960s , 1970s building of dams changed pattern completely. downstream mean monthly minimum–maximum 500 cubic metres (18,000 cu ft) 6,000 cubic metres (210,000 cu ft) per second; 1,000 cubic metres (35,000 cu ft) 3,900 cubic metres (140,000 cu ft) per second. medium-level floods especially, of kind ecology of lower zambezi adapted, happen less , have shorter duration. itezhi-tezhi dam s deleterious effects on kafue flats, has following effects:

fish, bird , other wildlife feeding , breeding patterns disrupted
less grassland after flooding grazing wildlife , cattle
traditional farming , fishing patterns disrupted.

ecology of delta

annotated view of zambezi river delta space.

as zambezi section applies buzi, pungwe, , save rivers drain zambezi basin. floodplains of these 4 rivers make world wildlife fund s zambezian coastal flooded savanna ecoregion. mixture of open grassland , freshwater swamp inland indian ocean in mozambique.

although dams have stemmed of annual flooding of lower zambezi , caused area of floodplain reduced have not removed flooding completely. cannot control extreme floods, have made medium-level floods less frequent. when heavy rain in lower zambezi combines runoff upstream, massive floods still happen , wetlands still important habitat. however, shrinking of wetlands further severe damage wildlife caused uncontrolled hunting of animals such buffalo , waterbuck during mozambique civil war , conflict has ceased floodplains become more populated, , further damming has been discussed. protected area of floodplain marromeu game reserve near city of beira.

although region has seen reduction in populations of large mammals, still home including reedbuck , migrating eland. carnivores found here include lion (panthera leo), leopard (panthera pardus), cheetah (acinonyx jubatus), spotted hyena (crocuta crocuta) , side-striped jackal (canis adustus). floodplains haven migratory waterbirds including pintails, garganey, african openbill (anastomus lamelligerus), saddle-billed stork (ephippiorhynchus senegalensis), wattled crane ( bugeranus carunculatus ), , great white pelican (pelecanus onocrotalus).

reptiles include nile crocodile (crocodylus niloticus), nile monitor lizard (varanus niloticus) , african rock python (python sebae), endemic pungwe worm snake (leptotyphlops pungwensis) , 3 other snakes endemic; floodplain water snake (lycodonomorphus whytei obscuriventris), dwarf wolf snake (lycophidion nanus) , eyebrow viper (proatheris).

there number of endemic butterflies.