Wetlands are natural or constructed; both types can be used for removal of metals, particles, etc. In constructed wetlands, the flow is constructed as surface flow, subsurface flow or vertical flow, or a mixture . The most important role of plants in wetlands is that they increase theresidence time of water, which means that they reduce the velocity and thereby increase the sedimentation of particles and associated pollutants. Thus, they are indirectly involved in water cleaning. Plants also add oxygen, thus providing a physical site of microbial attachment to the roots and generating
Was this article helpful?