Which management action helps reduce slope length-related erosion risk on rangeland slopes?

• A. Increasing bare soil exposure
• B. Deep tillage
• C. Reducing slope length
• D. Overgrazing

Answer: (C)

The key idea is that erosion on slopes is strongly influenced by how far water runs over the soil before it infiltrates or leaves the field. Shorter runout paths mean water has less energy and less volume to detach and transport soil, so erosion is reduced. Reducing the slope length lowers the gradient over which runoff travels, slows flow, increases opportunity for infiltration, and makes it harder for water to concentrate into rills and gullies. In practice, contouring, terracing, or creating short-segment slopes along the hillside are ways to shorten the effective slope length and limit erosion risk. The other actions would typically increase erosion risk: exposing more bare soil removes protective cover, deep tillage can disrupt soil structure and increase runoff, and overgrazing reduces vegetation cover that shields the soil.