How natural plants and wetlands purify water

Plants and wetlands purify water by acting as filter media. The roots of the plants and the wetlands would trap pollutants like sediments and hold onto the. In wetlands, the flow of water is slow allowing for the sediments to settle due to gravity onto the bottom where the plants would accumulate them into place. With this, excess nutrients would be remove and will prevent polluting bodies of water. Also, bacteria like E. coli and Salmonella can be filtered out from the water. There are plants that works excellent for filtering out pollutants like the lilies, hornwort, bulrushes and rushes.