As the river flows towards the southeast, the vegetation becomes lush and the river enters coastal rainforest near Onitsha, Nigeria less than km above the delta. The upland vegetation along the Benue River consists of tropical savanna and moist savanna-woodland.
Two endemic fish genera, Dagetichthys and Dasyatis , are present in the Niger-Benue ecoregion. The endemic Dagetichthys lakdoensis , a benthic, freshwater sole or flatfish, is the only freshwater representative of this family in Africa and lives primarily in the upper Benue Welcomme a.
Several fish species may undertake long-range migrations in this large savanna river. Most longitudinal migrations occur during the wet season when fish travel to spawning grounds. Anecdotal evidence exists of fish traveling up to km upstream towards the inner delta Welcomme a. One study found Brycinus leuciscus to travel at rates up to 9 km per day as floods receded, for a total distance of km Welcomme Several marine fish species, such as Trachinotus goreensis , Mugil cephalus , Pomadasys jubelini , and Cynoglossus senegalensis , migrate upstream as far as km above the delta and Eleotris spp.
Many fish of the Niger River have special adaptations for surviving the anoxic conditions that often occur during the dry season. Lungfish Protopterus possess lungs for aerial respiration and can also aestivate in a mucous cocoon in dry conditions, while other species are capable of burrowing in the mud or producing drought-resistant eggs Lowe-McConnell A representative of the Polypterus genus has lung-like modifications of the air bladder that allow it to breathe surface oxygen Welcomme a.
Many species in the genera Epiplatys , Aphyosemion, and Aplocheilichthys have dorsally-oriented mouths and a flattened head, which facilitates breathing from the surface film. This ecoregion comprises the Benue River basin and the lower and middle portions of the Niger River basin below the Inner Niger Delta [] and above the Niger Delta []. In contrast to conditions in the two deltas, the river is characterized by broad channels with numerous sandbanks and floodplains are limited in this ecoregion.
The river flows largely through savanna vegetation and the species assemblages are typical of the Nilo-Sudanian bioregion Roberts Obviously, the distribution and health of wetlands across the basin depend on water from the Niger River. These wetlands often have high biodiversity values and deliver ecosystem services that are important to the livelihoods of local people drinking water, small-scale irrigation, fishing etc.
In particular the riverine floodplains and exposed banks cover extensive areas. Important wetlands in the UNB include:. The Inner Niger Delta forms a huge floodplain ecosystem of Although it is a wetland of global importance the area at the same time is used by almost 2 million people for rice cultivation, grazing and fisheries. The Inner Niger Delta is vegetated with plant and tree species adapted to steep fluctuations in water level, seasonal flooding and long dry periods.
The presence of the main vegetation types is determined by the depth of water. During flooding, wild rice, bourgou, and also Vossia cuspidata known in other parts of Africa as Hippo Grass, but as didere in the Delta , form huge floating meadows.
In practice this refers to the Niger river proper and the deepest parts of the lakes. Their structure stems up to 6 m in length constitutes an ideal habitat for the reproduction and growth of first-year fish populations. Bourgou constitutes a key habitat for populations of several bird species, including those of resident and migratory herons and egrets.
Bourgou fields are essential as grazing ground for livestock through the dry season. Being essential as feed for the large herds, bourgou is often planted by the local populations. Wild rice vegetations Wild rice Oryza barthii and O.
Controlled submerged rice These rice fields are surrounded by small dikes and get flooded during high water levels. The dikes also keep the water in during the retreat of the flood. Rice cultivations People are cultivating an increasing proportion of the floodplains to grow rice. Cultivated rice Oryza glaberrima requires the same water depth zone as wild rice and flood forests, and so extension of cultivated rice fields occurs at the expense of natural habitats.
Mares ponds and water lilies Ponds are temporary habitats for fish, being used by local inhabitants for communal fishing when the flood retreats. In addition, the vegetation is exploited by waterbird populations, especially by Garganey feeding on water lily seeds.
Flood forests The flooded forests form a unique habitat in the IND. Brown pp states that de Lagarde is also of this opinion for he considers that the name Nile derives from the Semitic word el meaning river el is kindred with the Hebrew words nahar and naghal meaning river accept this derivation for the name Nile meaning in Semitic just river Eastern Whites drawn largely from Asia minor and hence belonging to the Semitic group of languages had penetrated extensive regions of western Africa For instance the diaspora sent Jews westwards and by A.
D Arabs had reached the Atlantic coasts in the regions of the Senegal river It would be unreasonable to expect no repercussions on locality names as result of this white invasion If now it is agreed that the sound in nahar or in nahal can also be represented by the sound gh then one realises how close Rendei Harris came to solving the etymologies of the names Nile and Niger when he wrote when we made the suggestions which gave us Negelos instead of Ne-ilos we see the river Niger looking out at us from the upper waters of the Nile and we remember that from the earliest times the Nile and the Niger were believed to be branches of the same stream..
More than the Niger looks at us from the waters of the Nile An early name for the Senegal river was Ce- naga r Thus from nahal derive the name Nile and from the dialectal variant naghar derive the names Niger and Senegal These two rivers were long regarded as one river and so would share common name hence the similarity in the roots Se-negal and Niger There is river in. Nile Encyclopedia Britannica lA ed. MEEK K. Timbuctu he grand ssima cidade jaz sobre ho ryo Ennyll.
Niger : Origins of the Word [article] M. Here one realises that words Nigeria and Nigerian derive from the name Niger JEFFREYS What then is the origin of the word Niger Because it flows through the land of the Negroes which for the Arabs was the Sudan Nigey was at first erroneously derived from the Latin world niger meaning black Gir The stem Gir is part of the word Niger and Crone editing the voyages of Ca da Mosto has some remarks on the two main river systems of the Sahara He writes geography of the interior of northern Africa is characterised by two hydrographical systems one formed by the Chelonidas Paludes and the river Gir with an independent Nuba Palus the other and more westerly by the river Nigir the Liby ae Palus and the Nigritis Palus These are said to flow in the middle of the land.
Mungo Park, the Scottish explorer who was the first known European to travel the central section of the Niger River in , died in when his party was attacked by natives and he drowned. The Niger River floods each year from September to May. The Niger River delta is home to the African Lion. The West African manatee, a creature near extinction lives in the Niger River.
The Niger River has been an important source of water to those in its region since the first inhabitants settled there.
0コメント