Environmental Hazard IV: Deforestation

Subject: Basic Science

Class: JSS 3

Term: First Term

Week: 8

Age: 12 – 14 years

Topic: Environmental Hazard – Deforestation

Sub-Topic: Causes, Effects, and Prevention of Deforestation

Duration: 40 minutes

Behavioural Objectives

By the end of the lesson, students should be able to:

1. Define deforestation.
2. List the reasons for deforestation (commercial and domestic).
3. Identify the effects of deforestation on the environment.
4. Suggest solutions to reduce deforestation.
5. Understand environmental regulations on deforestation.

Keywords

• Deforestation: The cutting down of trees or forests without adequate reforestation.
• Reforestation: Planting trees to replace those cut down.
• Commercial Logging: Cutting trees for industrial purposes.
• Erosion: Washing away of soil due to lack of vegetation.
• Carbon Sequestration: The process by which forests absorb carbon dioxide.

Set Induction

The teacher asks:

• “Have you ever seen large areas of land where all the trees were removed? What impact did this have on the environment?”
  This helps students connect the lesson to their environment and experiences.

Entry Behaviour

Students may have seen or heard about deforestation activities in their community or country.

Learning Resources and Materials

• Picture charts showing deforested areas and reforestation efforts.
• Video clips demonstrating the impact of deforestation.
• Maps of forested and deforested regions in Nigeria.

Building Background/Connection to Prior Knowledge

The teacher refers to previous lessons on soil erosion and flooding, explaining how deforestation worsens these hazards.

Embedded Core Skills

• Environmental Awareness: Understanding the role of forests in the ecosystem.
• Critical Thinking: Analyzing the consequences of deforestation.
• Civic Responsibility: Learning the importance of environmental laws and community involvement.

Instructional Materials

• Basic Science textbooks
• Lagos State Scheme of Work
• Markers and whiteboard

Content

1. Definition of Deforestation

Deforestation refers to the large-scale cutting down of forests without replacing the trees, often leading to environmental damage.

2. Reasons for Deforestation

1. Commercial Firewood: Trees are cut to produce wood for industrial purposes.
2. Domestic Firewood: Trees are used for cooking and heating in rural areas.
3. Agriculture: Land is cleared to grow crops or raise livestock.
4. Urbanization: Expanding cities and building infrastructure.
5. Logging: Trees are cut for timber and paper production.

3. Effects of Deforestation on the Environment

1. Soil Erosion: Without trees, rain washes away fertile soil.
2. Climate Change: Fewer trees mean less absorption of carbon dioxide, contributing to global warming.
3. Loss of Biodiversity: Animals lose their natural habitat.
4. Desertification: Deforested land becomes barren over time.
5. Flooding: Fewer trees lead to poor water absorption, increasing flood risks.

4. Regulations on Deforestation

1. Reforestation: Government encourages planting new trees to replace those cut down.
2. Forest Conservation Laws: Some areas are legally protected from logging.
3. Awareness Campaigns: Communities are educated on the dangers of deforestation.
4. Eco-friendly Alternatives: Promoting the use of alternative fuels like gas instead of firewood.

Board Summary

• Deforestation: Large-scale cutting of forests without replacement.
• Causes: Commercial firewood, agriculture, logging, urbanization.
• Effects: Soil erosion, biodiversity loss, climate change, flooding.
• Prevention: Reforestation, conservation laws, awareness campaigns.

Class Activity Discussion (FAQs)

1. What is deforestation?
   • The large-scale removal of forests without replanting trees.
2. Why do people cut down trees?
   • For firewood, agriculture, and building cities.
3. How does deforestation cause flooding?
   • Without trees, water cannot be absorbed into the soil.
4. What is reforestation?
   • Planting trees to replace those cut down.
5. What are some alternatives to firewood?
   • Gas, solar energy, and electricity.
6. How does deforestation affect animals?
   • It destroys their habitats, leading to extinction.
7. What role do trees play in controlling climate change?
   • Trees absorb carbon dioxide, reducing global warming.
8. What is biodiversity loss?
   • The disappearance of plants and animals from ecosystems.
9. How can communities prevent deforestation?
   • By participating in tree planting campaigns and using eco-friendly materials.
10. What happens if deforestation is not controlled?

• It leads to environmental problems like erosion, desertification, and flooding.

Teacher’s Activities

1. Display visuals showing the impact of deforestation.
2. Lead a discussion on the causes of deforestation in Nigeria.
3. Guide students to brainstorm solutions to deforestation.
4. Explain government regulations to protect forests.

Learners’ Activities

1. Share their experiences with deforestation in their community.
2. Participate in group discussions on preventing deforestation.
3. Complete worksheets on the causes and effects of deforestation.

Evaluation: 15 Fill-in-the-Blank Questions

1. __________ refers to the large-scale cutting down of trees without replacement.
   a) Deforestation
   b) Reforestation
   c) Afforestation
   d) Conservation
2. One cause of deforestation is __________ firewood.
   a) domestic
   b) industrial
   c) toxic
   d) commercial
3. Deforestation can lead to __________, where soil is washed away by rain.
   a) erosion
   b) irrigation
   c) fertilization
   d) combustion
4. A consequence of deforestation is the loss of __________.
   a) biodiversity
   b) factories
   c) rainfall
   d) minerals
5. The process of planting new trees is called __________.
   a) reforestation
   b) erosion
   c) logging
   d) urbanization
6. Cutting trees for paper and timber is known as __________.
   a) logging
   b) farming
   c) afforestation
   d) industrialization
7. __________ is an alternative fuel to firewood.
   a) Gas
   b) Plastic
   c) Diesel
   d) Charcoal
8. Deforestation contributes to __________ change by increasing carbon dioxide levels.
   a) climate
   b) population
   c) agricultural
   d) cultural
9. A law that protects forests is known as a __________ law.
   a) conservation
   b) deforestation
   c) plantation
   d) reforestation
10. Without trees, land may become barren, leading to __________.
    a) desertification
    b) reforestation
    c) urbanization
    d) conservation

Conclusion

The teacher summarizes the lesson, highlighting the importance of forests and the need to prevent deforestation. Students receive feedback on their answers.