Theory question 106
Nigeria: Physical Setting(a) On an outline map of Nigeria, locate and name (i) one inland drainage basin (ii) three rivers that flow into the basin (iii) the Bight of Benin and Bight of Bonny (iv) the Idanre Hill, Oban Hills and Biu plateau
(b) Account for the shallowness of the rivers and the lake of the inland drainage basin
(c) Describe any four benefits of the lake.
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(a) Chad basin; rivers Komadugu-Yobe, Hadejia, Jama'are (also El Beid, Ngadda); Bight of Benin (west coast) and Bight of Bonny (east coast); Idanre Hill (Ondo), Oban Hills (Cross River), Biu Plateau (Borno)
(b) Low and seasonal rainfall; very high evaporation and temperatures; flat, low gradient land; heavy silting with sand; seepage into porous sediments; dams and irrigation upstream take water; long dry season
(c) Fishing; irrigation farming around the lake (South Chad Irrigation Project); water for people and livestock; transport across the lake; fertile lake-bed farmland when the water recedes; tourism
Explain shallowness by water input versus loss.