Lesson Notes By Weeks and Term - Senior Secondary 1

TERM – 3^RD TERM

WEEK TWO

Class: Senior Secondary School 1

Age: 15 years

Duration: 40 minutes of 5 periods each

Date:

Subject: Geography

Topic: RELIEF AND DRAINAGE OF NIGERIA

SPECIFIC OBJECTIVES: At the end of the lesson, pupils should be able to

1. Identify with examples the major highlands and lowlands.
2. Highlight the advantages and disadvantages of highlands and lowlands.
3. Describe the distribution of drainage system (river and lakes) in Nigeria.
4. Examine the characteristics, importance and limitations of rivers in Nigeria

INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers,

demonstration, videos from source

INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, pictures

INSTRUCTIONAL PROCEDURES

PERIOD 1-2

NOTE

RELIEF AND DRAINAGE OF NIGERIA

Relief refers to the variations in elevation and terrain features of a land surface. It includes mountains, hills, valleys, plateaus, and other physical characteristics of the Earth's surface. Relief is a crucial aspect of geography, influencing factors such as climate, vegetation, and human settlement patterns.

Nigeria as a country is basically grouped into two; the lowlands and the highlands.

Lowlands in Nigeria

Lowlands typically are areas below 300m above the sea level. Examples of lowlands in Nigeria includes:

1. The Niger – Benue Trough / Valley (100 – 300m)
2. The Niger Delta (0 – 100)
3. The Sokoto Plain (200 – 300m)
4. The Cross River Basin (120 – 180)
5. The Coastal Plain (0 – 100)
6. The Chad Basin or Bornu Plain

Rocks associated with lowlands

The lowland areas in Nigeria, particularly in the Niger Delta region and surrounding coastal plains, are associated with sedimentary rocks such as shale, sandstone, and limestone. These rocks often characterize lowland regions due to the geological processes that have shaped these landscapes over time.

Advantages of Lowlands in Nigeria

1. Lowlands often have rich, fertile soil suitable for agriculture, promoting the cultivation of crops such as rice, maize, and vegetables.
2. The availability of water in lowlands supports consistent agricultural production, contributing to food security and economic stability.
3. Lowlands are generally more accessible, facilitating transportation and infrastructure development, which is crucial for economic growth and connectivity.
4. Lowlands serve as natural reservoirs, providing a potential source of water for irrigation, industrial processes, and domestic use.

Disadvantages of Lowlands in Nigeria

1. Lowlands are prone to flooding, especially during the rainy season, posing a threat to communities, agriculture, and infrastructure.
2. Stagnant water in lowlands can become a breeding ground for disease-carrying vectors, leading to an increased risk of waterborne diseases like malaria and cholera.
3. Continuous cultivation and improper land management in lowlands can lead to soil erosion and degradation, impacting long-term agricultural sustainability.

Highlands in Nigeria

Highlands are areas that are over 300m above the sea level. The major highlands in this region are

1. The Obudu Plateau above 1,584 m (5,197 ft),
2. Mambilla Plateau above 1,524 m (5,000 ft)
3. Mt. Chappal Waddi above 2,000 m (6,562 ft).

Rocks associated with highlands

1. Jos plateau is made up of volcanic rocks.
2. Udi hills are made up of Carboniferous sedimentary rock.
3. North central plateau, Western highland, Mandara Mountain, Shebshi, Alantika, Obudu and Oban hills are made up of basement complex rocks (a combination of igneous and metamorphic rocks).

Advantages of Highlands in Nigeria

1. Highlands often host diverse ecosystems, contributing to rich biodiversity and providing habitats for various plant and animal species.
2. Highlands serve as water catchment areas, supplying rivers and streams that are vital for both agricultural irrigation and domestic water supply.
3. The scenic landscapes of highlands can attract tourism, potentially boosting local economies through activities such as hiking, eco-tourism, and adventure sports.
4. Highlands may offer cooler temperatures compared to lowlands, creating favorable conditions for certain crops and providing relief from the heat.

Disadvantages of Highlands in Nigeria

1. The rugged terrain of highlands can limit the availability of arable land, making large-scale agriculture challenging and potentially affecting food production.
2. The steep slopes and challenging topography of highlands can hinder transportation and infrastructure development, impacting connectivity and economic growth.

3. High-altitude areas are susceptible to soil erosion, especially if vegetation cover is removed, leading to the degradation of fertile soil.

 Drainage system in Nigeria

Nigeria's drainage system is characterized by a network of rivers and lakes distributed across various regions.

Rivers:

1. Niger River: One of Africa's longest rivers, the Niger River flows in a curved course through Nigeria, creating a significant drainage basin.
2. Benue River: The Benue River is a major tributary of the Niger River, originating in the Cameroonian highlands. It flows through central Nigeria, contributing to the overall drainage pattern.
3. Cross River: Originating in Cameroon, the Cross River flows through southeastern Nigeria, forming part of the country's drainage system and supporting agriculture in the region.
4. Kaduna River: A tributary of the Niger River, the Kaduna River flows through north-central Nigeria, adding to the country's diverse river network.

Lakes:

1. Lake Chad: Although shared with other African countries, Nigeria has a portion of Lake Chad in its northeastern region. The lake's water levels have fluctuated over the years, impacting the local ecology and communities.
2. Kainji Lake: Formed by the Kainji Dam on the Niger River, this artificial lake is significant for hydroelectric power generation and contributes to the overall water resources in Nigeria.
3. Oguta Lake: Located in southeastern Nigeria, Oguta Lake is one of the natural lakes in the country, contributing to the regional drainage system.

Characteristics of Rivers in Nigeria

1. Diverse Sizes: Nigeria is home to rivers of varying sizes, from major ones like the Niger and Benue to smaller tributaries, contributing to a diverse hydrological landscape.
2. Seasonal Variability: Some rivers exhibit seasonal variations in flow, with water levels rising during the rainy season and decreasing in the dry season, impacting their usability for different purposes.
3. Fluvial Erosion: Rivers in Nigeria are associated with fluvial erosion, particularly in areas with poor land management practices, leading to soil degradation and changes in river courses.
4. Biodiversity: Rivers support diverse aquatic ecosystems, hosting various fish species and contributing to the overall biodiversity of the regions they traverse.

Importance of Rivers in Nigeria

1. Rivers are a crucial source of freshwater for agricultural irrigation, industrial processes, and domestic use, contributing significantly to the country's water resources.
2. Many rivers serve as natural transportation routes, facilitating the movement of goods and people. The Niger River, for example, is navigable and plays a vital role in transportation.
3. Rivers with dams, like the Niger River (Kainji Dam), contribute to hydropower generation, providing electricity for both urban and rural areas.
4. River valleys often have fertile soils, supporting agriculture along their banks and contributing to food production and livelihoods.

Limitations of Rivers in Nigeria

1. Rivers can pose a threat of flooding, particularly during the rainy season, causing damage to infrastructure, farmlands, and communities.
2. Increased human activities along riverbanks can lead to water pollution, affecting the quality of water for both aquatic life and human consumption.
3. Uncontrolled human activities, deforestation, and improper land use contribute to erosion and sedimentation in rivers, impacting their health and navigability.
4. Competition for water resources among different sectors, such as agriculture, industry, and urban development, can lead to conflicts over water use and allocation.

EVALUATION: 1. Identify 3 lowlands and 3 highlands in Nigeria

2. Mention 2 advantages and 2 disadvantages of highlands in Nigeria
3. Give 3 importance of Rivers in Nigeria
4. Identify 4 limitations of rivers in Nigeria

CLASSWORK: As in evaluation

CONCLUSION: The teacher commends the students positively