Soil Conservation

Why conserve soil?

Topsoil is the thin, fertile layer that feeds crops. When it is lost, farms produce less food. The KICD Grade 5 Agriculture curriculum teaches learners to protect soil, which matters in hilly areas such as Murang'a, Kisii and Elgeyo Marakwet.

Soil erosion

Soil erosion is the removal of topsoil by water, wind or animals.

Causes

• Heavy rain on bare land
• Overgrazing by livestock
• Cutting down trees (deforestation)
• Ploughing up and down a slope
• Burning vegetation

Effects

• Poor harvests and hunger
• Gullies in the land
• Mud in rivers and dams
• Floods and landslides

Conservation methods

1. Terracing: building steps across a slope to slow water.
2. Contour ploughing: ploughing across the slope, not down it.
3. Mulching: covering soil with dry grass or leaves.
4. Planting trees and grass: roots hold soil together.
5. Cover crops: such as sweet potato vines that cover the ground.
6. Controlled grazing: not keeping too many animals on one field.
7. Cut-off drains: channels that direct water away safely.

Community action

Kenyans protect soil through tree-planting days and Nyayo-style soil campaigns. School agriculture clubs can plant Napier grass on terrace edges.

Try it

• Pour water on a bare slope and on a grass-covered slope. Compare what happens.
• List three ways to conserve soil at home.
• Draw a terraced farm.