Phytoremediation by Constructed Wetlands

Abstract

A constructed wetland is a wastewater treatment facility that duplicates the processes in natural wetlands. Constructed wetlands are complex, integrated systems in which water, plants, animals, microorganisms, and the environment interact to improve water quality. Phytoremediation, defined as cleansing of the environment using vegetation, is the primary water treatment process in constructed wetlands. The advantages of phytoremediation using constructed wetlands are that it is environmentally friendly, a sustainable technology, and cost‐effective; the primary disadvantages are potentially incomplete removal of pollutants and pest attraction. Successful implementation of phytoremediation technology in constructed wetlands is a function of a number of interrelated biophysicochemical factors, including the types and fate of toxicants, characteristics of soil and sediment, plant species and plant uptake, hydrology and water flow, and microbial population. Hence, phytoremediation by constructed wetlands generally reflects an integrated multidisciplinary effort that combines plant biology, microbiology, surface chemistry, hydrology, and environmental engineering. The initial construction of wetlands, taking into account all these factors to design the most appropriate and effective method for removing target pollutants is labor‐intensive and expensive, but low maintenance and operating costs make constructed wetlands a much more economically viable alternative to conventional physical and chemical treatments. Above all, the use of plants in environmental cleanup may guarantee a greener and cleaner planet for us and for future generations.