Causes and effects of soil erosion

This Biology lesson for Form 1, taught by Toulack Kingsley, explores the various causes and consequences of soil erosion. The lesson identifies several primary human-induced and environmental causes, including overgrazing, deforestation (cutting down trees for fuel or land), overtillage which loosens soil particles, and bush burning which destroys vegetation and soil microorganisms. Other factors discussed include planting crops down the contour of slopes instead of along them, drought conditions associated with climate change, and the excessive use of chemical fertilizers that turn soil powdery. The effects of soil erosion are severe, leading to decreased soil fertility and inadequate food production, which results in starvation and widespread poverty among farmers. Furthermore, the lesson highlights secondary consequences such as the migration of populations from affected areas to more fertile land, water pollution when fertilizers are washed into water bodies, and respiratory health issues caused by wind-blown dust. Key definitions reviewed from the previous lesson include wind and water erosion, with water erosion being categorized into sheet and gully erosion.