What do wetlands primarily improve in ecosystems?

Wetlands play a crucial role in improving water quality within ecosystems. They act as natural filters, trapping pollutants, sediments, and excess nutrients from surface runoff before these substances can enter larger bodies of water, such as rivers and lakes. The biological processes occurring in wetlands—including the absorption by plants and the decomposition of organic matter—further enhance their ability to purify water. Microbial activity also breaks down harmful substances, thereby contributing to the reduction of toxins and pathogens.

While nutrients are important for ecosystems, wetlands specifically address issues of water quality rather than simply increasing nutrient density. Soil compaction is generally not a function attributed to wetlands; instead, wetlands often have organic soils that can retain water effectively without compaction. Additionally, while wetlands can contribute to air quality indirectly—such as through the absorption of carbon dioxide—this is not their primary function. The main ecosystem service provided by wetlands is their profound impact on enhancing and maintaining clean water.