In what way can wetlands contribute to water quality?

Wetlands play a crucial role in enhancing water quality through their natural filtration processes. They serve as barriers against pollutants by absorbing excess nutrients, sediment, and some contaminants from runoff before the water enters other bodies of water. The vegetation in wetlands, such as grasses and shrubs, helps trap and stabilize soil, which reduces erosion and further prevents pollutants from being carried into larger water systems.

Additionally, wetlands can facilitate biochemical processes that break down harmful substances, thus improving overall water quality. They also provide habitat for a diverse range of species, which contributes to ecosystem balance. The other options do not accurately reflect the function of wetlands; increasing water temperature or solely supporting fish populations ignores the broader ecological benefits they provide, while claiming they have no impact on surrounding ecosystems dismisses their important role in maintaining environmental health.