ABSTRACT
Water is a non-replaceable natural asset, pollution of which is one of the most significant issues of concern at the global level. The water purification proficiency of wetlands is now being renowned as an eye-catching choice in wastewater treatment. Construction of wetland for treatment of water and wastewater is one of the eco-friendly and cost-efficient methods that do not generate secondary pollutants. These are engineered wetlands designed and constructed to mimic natural wetland systems for treating water and wastewater. They work on the principle of collective interactions of water, substrate, soil, plants, and microbes. The main advantage of wetlands lies in the usage of natural processes for treating different kinds of wastewater as well as drinking water. Almost all kinds of water pollutants, e.g., nitrates, chlorides, heavy metals, and organic pollutants can be treated with the help of wetlands. The main factors that affect the pollutant removal by wetlands are different mechanisms involved in the uptake of pollutants by the plants and its degradation or conversion into less toxic substances by different microbial activities. Furthermore, aquatic plants used in wetlands also add esthetic value to the location of the system. In the present study, a detail account of wetlands, their composition, properties, working, and advantages in terms of plant–water–soil relationships have been discussed.
