What role do wetlands play in reducing pollution?

Wetlands are crucial ecosystems that serve a variety of functions, one of the most important being their ability to filter pollutants from water. They act as natural buffers, absorbing excess nutrients, sediments, and contaminants from surface water runoff before it reaches larger bodies of water, such as rivers or lakes.

This filtration process occurs through a combination of physical, chemical, and biological processes. As water flows through wetland vegetation and soil, pollutants can be trapped, broken down, or converted into less harmful substances by the microbial community present in these systems. The presence of plant roots and complex soil structures enhances this filtering capability, allowing wetlands to effectively reduce nitrogen and phosphorus levels that can lead to eutrophication in nearby water bodies.

The other choices do not accurately represent the role of wetlands. Certain functions, such as providing recreational areas or promoting algae growth, do not align with the principal ecological benefits wetlands offer regarding pollution control. Increased water temperature is generally a negative impact associated with human activities and does not reflect a function of wetland ecosystems. Thus, the role of wetlands in filtering pollutants is a significant service they provide to maintain water quality and ecosystem health.