Which is a key ecologic function of wetlands and green infrastructure in water quality protection?

• A. Wetlands filter pollutants, trap sediments, and support microbial degradation; green infrastructure like bioswales and rain gardens reduce runoff and nutrient loading.
• B. Wetlands release pollutants; green infrastructure increases runoff.
• C. Wetlands store pollutants permanently; green infrastructure replaces wastewater treatment.
• D. Wetlands are only for wildlife; green infrastructure only aesthetics.

Answer: (A)

Wetlands and green infrastructure protect water quality by using natural processes to remove pollutants and slow or reduce the flow of water. Wetlands filter pollutants, trap sediments, and support microbial degradation, while the roots and soils create conditions for nutrient uptake and processes like denitrification. Green infrastructure—bioswales, rain gardens, and similar features—slows runoff, increases infiltration, and promotes sediment settling and nutrient uptake by plants and soil microbes, all of which lowers pollutant and nutrient loads entering water bodies. The other statements don’t fit because wetlands don’t release pollutants or store them permanently, and green infrastructure does more than aesthetics—it helps manage runoff and pollution.