(a) On a sketch map of Nigeria, mark and name the following (i) the Western Uplands, the Udi Hills and the North Central Plateau (ii) one important river ba...

(a) Identification on the sketch map

As shown on the map above, the following features should be correctly located and labelled:

• Western Uplands: located in south-western Nigeria, mainly around the Yoruba highlands of Oyo, Ogun, Osun, Ondo and Ekiti areas.
• Udi Hills: located in south-eastern Nigeria, west of Enugu, around the Udi-Enugu area.
• North Central Plateau: located in central Nigeria, around Jos in Plateau State.
• River basin: the Niger-Benue River Basin, covering much of central Nigeria where River Niger and River Benue meet at Lokoja.
• Natural lake: Lake Chad, in the north-east, on Nigeria's border with Chad, Niger and Cameroon.
• Man-made lake: Kainji Lake, in north-western Nigeria on River Niger. It was formed by the construction of Kainji Dam.

(b) Importance of river basins in the development of Nigeria

• Agriculture: River basins have fertile alluvial soils which support crop cultivation. For example, the flood plains of the Niger-Benue Basin support the cultivation of rice, maize, vegetables and sugar cane, while the Chad Basin supports wheat, rice, tomatoes and vegetables.
• Irrigation: Water from rivers and reservoirs is used to irrigate farmland, especially in the dry northern region. Examples include the Kano River irrigation scheme, Bakolori irrigation project and irrigation around the Hadejia-Jama'are and Chad basins.
• Hydroelectric power generation: Rivers provide water for generating electricity. Kainji, Jebba and Shiroro dams on the Niger River system produce hydroelectric power for homes, industries and commercial activities.
• Fishing: Rivers, lakes and flood plains provide fish and employment for fishing communities. Fishing is important around Lake Chad, Kainji Lake, River Niger and the Niger Delta creeks.
• Water supply: River basins supply water for domestic use, industries and livestock. Major towns obtain treated water from rivers, dams and reservoirs within their drainage basins.
• Transportation and trade: Parts of River Niger and River Benue are navigable during high-water periods. They facilitate the movement of people and goods, particularly between Lokoja, Onitsha, Warri and other riverine settlements.
• Settlement and industry: River valleys provide relatively flat land, water and fertile soils, encouraging settlement and industrial activities. Important towns such as Lokoja, Onitsha, Makurdi and Yola developed along major river basins.
• Tourism and recreation: Lakes and dams such as Kainji Lake attract tourists and support recreational activities such as boating, fishing and wildlife conservation in the Kainji Lake National Park area.

(c) Factors limiting the use of river basins in Nigeria

1. Seasonal flow of rivers: Many rivers have reduced water volume in the dry season, making irrigation, navigation, fishing and water supply difficult at certain times of the year.
2. Swampiness and flooding: Flood plains and deltaic areas are often waterlogged or flooded. This makes road construction, farming, settlement and other development projects difficult and costly.
3. Poor accessibility: Many river-basin areas, especially swampy and remote parts of the Niger Delta and Chad Basin, have inadequate roads and transport facilities. This limits the movement of people, farm produce and equipment.