What is one function of wetlands?

Wetlands play a crucial role in ecosystems, one of their key functions being the absorption and removal of pollutants from water. This process, known as bioremediation, occurs through natural mechanisms involving soil, vegetation, and microbial activity. Wetlands filter out sediments, excess nutrients like nitrogen and phosphorus, and harmful contaminants, improving the overall water quality of nearby rivers, lakes, and streams.

For example, the vegetation in wetlands, such as cattails and reeds, helps trap sediments and can take up some contaminants directly through their roots. Moreover, anaerobic bacteria found in wetland soil can break down organic pollutants, making wetlands vital for mitigating pollution in surrounding aquatic environments. This function not only supports the health of ecosystems but also benefits human communities by enhancing water quality for drinking, recreation, and wildlife.

Other options do not accurately represent the primary functions of wetlands. Wetlands typically reduce salinity rather than increase it, they are not specific habitats for marine mammals, and while they can produce phytoplankton, their primary role is not to generate large volumes of it but rather to maintain water filtration and habitat stability.