Soil

Syllabus tag: KCSE | Geography | Form 3 | Topic 28 Soil

Lesson objectives

By the end of this topic, you should be able to:

• State the composition of soil and the factors influencing its formation.
• Describe the soil forming processes and the soil profile.
• Describe soil properties and the soil catena.
• Explain soil degeneration, erosion and conservation measures.

Summary

Soil is the thin loose layer on the earth's surface in which plants grow. It contains mineral matter, organic matter, water and air. Its formation depends on parent material, climate, living organisms, topography and time. A soil profile is a vertical section showing horizons A, B, C and D. Erosion is its greatest threat.