Soil roughness applied to a Disturbed Soil Area (DSA) tends to

Soil roughness applied to a Disturbed Soil Area (DSA) tends to

• A. Promote sedimentation
• B. Reduce erosion
• C. Have no effect
• D. Increase erosion

Answer: (B)

Increasing surface roughness on a disturbed soil surface reduces erosion. When the soil is disturbed, it’s bare and easily detached by raindrop impact and carried away by surface runoff. Adding roughness—through elements like mulch, straw, wood fibers, or small ridges—creates obstacles that slow down advancing water, increase friction, and promote water infiltration. This energy dissipation lowers the shear stress acting on the soil particles, making it harder for particles to detach and be transported. The slowed runoff also allows more time for sediment to settle within the roughened surface, and the area becomes more conducive to vegetation establishment, which provides long-term stabilization. Because of these effects, soil roughness lowers erosion rather than increasing it or having no effect.

Increasing surface roughness on a disturbed soil surface reduces erosion. When the soil is disturbed, it’s bare and easily detached by raindrop impact and carried away by surface runoff. Adding roughness—through elements like mulch, straw, wood fibers, or small ridges—creates obstacles that slow down advancing water, increase friction, and promote water infiltration. This energy dissipation lowers the shear stress acting on the soil particles, making it harder for particles to detach and be transported. The slowed runoff also allows more time for sediment to settle within the roughened surface, and the area becomes more conducive to vegetation establishment, which provides long-term stabilization. Because of these effects, soil roughness lowers erosion rather than increasing it or having no effect.