THE FORMATION OF THE SOIL
AGRICULTURAL SCIENCE THIRD TERM E NOTES FOR BASIC FOUR
3rd Term Agricultural Science
Primary 4
Subject : AGRICULTURAL SCIENCE
Topic : FORMATION OF SOIL
Class : BASIC FOUR / PRIMARY 4 / GRADE 4
TERM : THIRD TERM
WEEK : WEEK 4
LEARNING MATERIALS
- Whiteboard/Chalkboard
- Explanatory posters/pictures
- Explanatory videos
Instructional Materials :
- Lagos State Scheme of Work.
- Online Materials.
- Textbooks
- Workbooks
- Different types of soil
Previous Knowledge :
The pupils have been taught
in their previous lesson
PERFORMANCE OBJECTIVES
At the end of the lesson , pupils should be able to
1. say how soil is formed
Content :
FORMATION OF SOIL
Soil formation show us how soil is formed. Soil is formed when rocks break down into smaller particles. It can also be called Weathering. This happens as a result of the following Agents.
Weathering is the process of breaking down rocks into simpler units or forms to form soil.
Agents of soil formation
The agent of soil formation is:
Rain
Temperature
Wind
Man
Animals
Plants
RAIN
When rain falls, it touches the rocks which tears out tiny pieces of rocks. The water from the rain will wash these pieces of rock to form soil
TEMPERATURE
High temperature makes rock to expand, crack and break down into small pieces. It is cause by hot sun or heat
WIND
When heavy wind blows, it will blow away small pieces of rocks from the large ones which creates more room for loose rock to fall which later turn to soil.
MAN
Man help in soil formation when he/she make use of some farm tools like hoe on rocky areas, he try to break the little rocks or stones which later turn to soil. Man splitting firewood on the rock or breaking objects on the rock leads to soil formation.
ANIMALS
When huge animal like cattle’s, elephant walk on a rocky place, it breaks the rock into smaller pieces thereby forming soil. Also when animal dies their body decays and mixed with the soil.
PLANT
As plant keeps growing, the root of the plants keep expanding and getting strong on the ground. Like the root of trees breaks down rock particle during expansion and growth. Also when plants die their body decays and mixed with the soil.
THE PROCESS OF SOIL FORMATION
The decomposition and dissolution of rocks through weathering and with the help of soil organisms like earthworm. Bacteria, fungi, protozoa and the help of chemical substances in the soil bring about soil formation
Presentation
The topic is presented step by step
Step 1:
The class teacher revises the previous topics
Step 2.
He introduces the new topic
Step 3:
The class teacher allows the pupils to give their own examples and he corrects them when the needs arise
Evaluation:-
Theory
- What is weathering?
- What is soil formation?
- What are the agents of soil formation
- Mention four agents of weather
- How does temperature affect soil formation
Objectives
Answer the following questions
- The process whereby rocks are broken down to form soil is known as ______ (a) Transformation (b) Weathering (c) Osmosis
- The parent materials of soil are ______ (a) Men (b) Rocks (c) Mineral resources
- The processes of breaking down rocks are physical, chemical and ______ (a) biological (b) systematic (c) Manually
- ______ makes the rock to expand, crack and break down into small pieces. (a) Rainfall (b) High temperature (c) Tension
Conclusion :
The teacher summarize the lesson. He or she gives out a board summary of the topic as note . He or she goes round to mark and does the necessary corrections
