In the context of water quality, what is one direct effect of sediment from erosion?

• A. It increases turbidity and can lead to deposition of suspended sediments.
• B. It purifies water by filtering contaminants.
• C. It increases dissolved oxygen levels.
• D. It reduces nutrient availability to aquatic plants.

Answer: (A)

Sediment from erosion directly adds suspended particles to the water, making it more turbid or cloudy. That increased turbidity reduces light penetration, which can hinder photosynthesis in aquatic plants and affect habitat and clarity of the stream or lake. As these particles settle, they don’t improve water quality; they deposit on the bottom and can smother habitats. The other statements don’t describe what sediment does right away: it doesn’t purify water by filtering contaminants, it doesn’t raise dissolved oxygen (in fact, turbidity can limit oxygen production and decomposition can consume oxygen), and while sediment can interact with nutrients in complex ways, the immediate, direct effect of erosion-derived sediment is the rise in turbidity and deposition of suspended sediments.