Which practice would best reduce nutrient runoff in a watershed?

• A. Buffer strips and best management practices to reduce runoff.
• B. Clear-cutting riparian zones.
• C. Routine fertilizer application near streams.
• D. Draining wetlands for development.

Answer: (C)

Managing nutrient runoff hinges on keeping nutrients out of streams by slowing, filtering, and absorbing them before they reach water bodies. Vegetated buffers along waterways and practices that limit how fertilizers are applied are two of the most effective tools. Buffer strips—pronounced bands of grasses or shrubs beside streams—trap sediments and absorb or take up nutrients from surface runoff, while their roots help hold soil in place, reducing erosion. Best management practices optimize when, where, and how much fertilizer is applied, and also promote soil health and reduced disturbance (for example, conservation tillage, cover crops, and nutrient management plans). Together, these approaches lower both the volume of runoff and the nutrient load it carries, protecting water quality and aquatic life.

Why the other options don’t fit as well: removing vegetation in riparian zones destabilizes banks and increases runoff and erosion, delivering more nutrients to streams; applying fertilizer routinely near streams adds nutrients directly to the hydrologic pathway that leads to water bodies; draining wetlands eliminates natural storage and filtration zones, releasing stored nutrients and reducing the landscape’s capacity to filter pollutants.