How are soil erosion and soil fertility linked to sustainable farming practices?

• A. Erosion increases soil fertility through mineral exposure.
• B. Erosion has no impact on yields.
• C. Erosion depletes soil health and yields; practices like contour farming, cover crops, terraces, and reduced tillage protect soil fertility.
• D. Erosion only occurs in wetlands.

Answer: (C)

Soil erosion and soil fertility are linked because when erosion wears away the topsoil, the most fertile part of the soil—the layer rich in organic matter and nutrients—is lost. That topsoil loss directly lowers soil health and crop yields. Sustainable farming practices are designed to slow or stop that loss, helping keep fertility in place.

Erosion depletes soil health and yields; practices like contour farming, cover crops, terraces, and reduced tillage protect soil fertility by reducing runoff, preserving organic matter, and improving soil structure. Contour farming follows the land’s shape to slow water flow and keep soil from washing away, especially on slopes. Cover crops shield the soil from raindrop impact, add biomass and nutrients when they decompose, and improve soil structure and moisture-holding capacity. Terraces break a steep slope into flat steps, dramatically decreasing runoff and preventing topsoil loss on hillsides. Reduced tillage minimizes disturbance, keeps crop residues on the surface to protect soil, and preserves soil structure and beneficial organisms, reducing erosion and nutrient leaching.

By limiting erosion, these practices help maintain nutrient levels and soil moisture, supporting higher and more stable yields over time. In contrast, the idea that erosion increases fertility or that it has no impact on yields is incorrect, and erosion is not confined to wetlands—it occurs in many landscapes where rainfall, wind, or slope erode the soil.