Lesson Notes By Weeks and Term - Senior Secondary 2

TERM – 1^ST TERM

WEEK ONE

Class: Senior Secondary School 2

Age: 16 years

Duration: 40 minutes of 5 periods each

Date:

Subject: Geography

Topic: EARTHS EXTERNAL PROCESSES AND LANDFORM DEVELOPMENT (ACTION OF RUNNING WATER)

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

1. Describe water as an energy system.
2. Identify the stages of rivers and their characteristics.
3. Explain the processes associated with each stage
4. describe the features associated with each stage of the river and their benefits to man

INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers,

demonstration, videos from source

INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, pictures

INSTRUCTIONAL PROCEDURES

PERIOD 1-2

NOTE

EARTHS EXTERNAL PROCESSES AND LANDFORM DEVELOPMENT (ACTION OF RUNNING WATER)

Water as an Energy.

Water can be harnessed as a renewable energy source through hydropower. The kinetic energy of flowing water such as in rivers or dams, is used to generate electricity, this renewable energy form is environmentally friendly and plays a significant role in global power production.

Stages of a River

Rivers typically go through several stages as they flow from their source to the mouth. These stages include:

1. Source/Headwaters: The source or headwater of a river refers to the point where the river begins, typically at the highest elevation. It is the starting point of the river's flow, often located in mountainous or hilly regions.

 Characteristics:

The characteristics of a river's source or headwaters include:

1. The river often begins as small, narrow streams at higher elevations.
2. Being in mountainous or hilly areas, the source area tends to have cooler temperatures.
3. The initial path of the river is typically confined to a narrow channel.
4. Water at the source is often clear and cold due to its origin in higher altitudes..

2. Youthful/Upper Course: The youthful or upper course of a river refers to the section where the river begins, typically in highland or mountainous terrain. In this phase, the river is characterized by steep gradients, rapid flow, and erosion, shaping its course and forming features like V-shaped valleys.

Characteristics

1. The youthful river has a steep slope or gradient as it descends from its source in the mountains, leading to swift water flow.
2. Erosion by the fast-moving water creates V-shaped valleys, carving through the landscape over time.
3. As the river cuts through the uneven terrain, it may encounter rapids and waterfalls, showcasing the erosive power of the water.
4. Sediment transport is more dominant than deposition in the youthful stage, as the river primarily focuses on carrying away eroded material.

 Benefit of youthful/upper course river to Man

The benefits of a youthful or upper course river to Man include:

1. The steep gradient and rapid flow in the upper course provide an opportunity for hydropower generation, contributing to renewable energy sources.
2. The V-shaped valleys and dramatic landscapes attract tourism, providing recreational opportunities and supporting local economies.
3. The clear, fast-flowing water in the upper course can serve as a source of clean and fresh water for drinking and agricultural purposes.
4. The valleys formed through downcutting erosion create natural transportation routes, facilitating trade and connectivity.

3. Mature/Middle Course: The mature or middle course of a river represents an intermediate stage in its development. In this phase, the river exhibits distinctive characteristics related to its flow, erosion, and sedimentation processes.

1. The gradient of the river is less steep compared to the youthful stage, leading to a more moderate flow and reduced erosive power.
2. The river channel widens as a result of prolonged lateral erosion, creating a broader and more stable watercourse.
3. Meanders, or winding bends, may develop as the river swings from side to side across its floodplain, sculpting a more sinuous path.
4. The river carries a greater load of sediment acquired from upstream erosion, leading to increased sediment transport and deposition.

Benefits of mature/middle course river to Man

The mature or middle course of a river offers several benefits to humanity:

1. Meanders and floodplains in the middle course provide fertile soils, ideal for agriculture. These areas support the cultivation of crops, contributing to food production.
2. The moderate gradient allows for controlled water flow, enabling efficient irrigation systems that enhance agricultural productivity.
3. III. The meandering nature of the river in this stage, along with associated landscapes, provides opportunities for recreational activities such as boating, fishing, and hiking, boosting tourism.
4. While not as pronounced as in the youthful stage, the moderate flow in the middle course can still offer hydropower potential, contributing to energy generation.
5. The river's flow in the middle course often serves as a consistent and reliable source of water for human consumption and industrial needs.

4. Old Age/Lower Course: The old age or lower course of a river represents the final stage in its lifecycle as it approaches the sea. This phase is characterized by distinct features and behaviors:

1. The river has a minimal slope or gradient in its lower course, leading to a slow and tranquil flow towards the sea.
2. The river channel is significantly wider and deeper due to prolonged erosion and sediment deposition over time.
3. The river carries a substantial amount of sediment, acquired from upstream erosion, contributing to the formation of deltas and sedimentary deposits.
4. Near the river's mouth, deltas may form as sediment is deposited at the point where the river meets a body of water, creating a fan-shaped landform.
5. The flow of water becomes sluggish as the river loses much of its energy, resulting in a slow and meandering movement towards the sea.

Benefits of old age/lower course river to Man

The old age or lower course of a river offers various benefits to humanity:

1. Delta formations in the lower course provide fertile soils, supporting agriculture. Deltas become valuable areas for cultivating crops due to the accumulation of nutrient-rich sediment.
2. Estuaries, formed in the lower course, are rich ecosystems where freshwater meets saltwater. These areas support diverse marine life, providing fishing opportunities and supporting commercial fisheries.
3. The mouth of the river in the lower course often forms ports and harbors. These become crucial for shipping, trade, and transportation, contributing to economic activities and global commerce.
4. The wide and deep channel in the lower course facilitates navigability, allowing for efficient transportation of goods and fostering trade along the river.
5. While the energy in the lower course is less intense compared to the youthful stage, there may still be hydropower potential due to the consistent flow of water.

EVALUATION: 1. Describe water as a source of energy system

            2.dentify the stages of a river and discuss two characteristics each.

3. Mention 3 benefits of a youthful/upper course river to man
4. Mention 3 benefits of a old age/lower course river to man

CLASSWORK: As in evaluation

CONCLUSION: The teacher commends the students positively