The loss of soil through erosion can be reduced by?

Analyze the question The question asks which practice helps reduce soil erosion, which is the washing or blowing away of topsoil by water or wind.

Explain the concept Soil erosion is controlled by keeping the soil covered and held together. Common methods include:

• Cover cropping and planting grass
• Afforestation (planting trees) and shelterbelts
• Terracing and contour ploughing
• Crop rotation, which keeps the soil covered and its structure good
• Mulching

Solution: checking each option

• A. Watering: Adding water, especially heavy watering, can loosen soil and increase runoff. It does not reduce erosion.
• B. Crop rotation: Different crops with different root systems and canopy cover are grown in turn. This keeps the soil covered and bound by roots, improves its structure, and avoids leaving land bare for long. This helps reduce erosion.
• C. Manuring: Manure mainly adds nutrients and organic matter, so it improves fertility. It can help soil structure a little, but its main purpose is fertility, not erosion control.
• D. Irrigation: Supplying water to crops can actually promote erosion if it is poorly managed, because it causes runoff.

Answer The best choice is B. crop rotation.

Tip For "erosion control" questions, think "cover and hold the soil": cover crops, trees, terracing, contour ploughing, and crop rotation. Fertility answers, such as manuring and fertilizers, are about nutrients, not erosion.