Explain the role of soil health in reducing non-point source pollution.

• A. Healthy soils reduce water retention and increase runoff.
• B. Healthy soils retain more water, improve infiltration, reduce erosion, and support vegetation, thereby lowering runoff and nutrient losses.
• C. Soil health has no impact on non-point pollution.
• D. Healthy soils increase nutrient losses.

Answer: (B)

Soil health affects how water moves across the landscape and how nutrients are lost, which is central to reducing non-point source pollution. When soils are healthy, they have better structure, more organic matter, and active roots and microbes that create stable aggregates and many pore spaces. This makes the soil sponge-like enough to hold more water and allow it to infiltrate rather than run off quickly. That infiltration lowers the volume and speed of surface runoff, which in turn reduces the erosion of soil particles that often carry attached nutrients into nearby streams.

Healthy soils also support robust vegetation, whose roots bind the soil and whose canopy protects it from raindrop impact. This vegetation reduces both erosion and the amount of nutrient carried away with sediment. The biological activity in healthy soils helps take up and immobilize nutrients like nitrogen and phosphorus, so less of these nutrients are available to be washed away in runoff.

All of these factors—greater water retention and infiltration, reduced erosion, and active plant and microbial nutrient use—mean fewer sediments and nutrient losses reach water bodies, directly addressing non-point source pollution.