Phytoremediation of contaminated waters: An eco-friendly technology based on aquatic macrophytes application

Abstract

The quality of waters is disturbing day by day by various inorganic and organic pollutants. Among various strategies developed so far the technique of phytoremediation using aquatic plants is most preferable. Aquatic ecosystems are facing high level of stress and depletion due to the inputs of polluting materials. Nonetheless, there are certain species of aquatic macrophytes that have ability to cope with these stressful conditions even high concentration of various organic and inorganic pollutants present in water. These species are useful in polluted water treatment through phytoremediation or bioremediation technologies. Among the various aquatic plant species, Azolla, Eichhornia, Lemna, Potamogeton, Spirodela, Wolfia, and Wolfialla have been reported as phytoremediators and also they are highly efficient in reducing aquatic contamination through bioaccumulation of contaminants in their body tissues. Among the various aquatic species, water hyacinth (Eichhornia) is highly resistant and can tolerate the toxicity of heavy metals, phenols, formaldehydes, formic acids, acetic acids and oxalic acids even in their high concentrations. Likewise some other species of the family Lemnaceae are very efficient to reduce the percentage of biochemical oxygen demand (BOD), chemical oxygen demand (COD), as well as impact of HMs (heavy metals), and various ionic forms of nitrogen and phosphorus. Here in this review we are providing up-to-date information regarding the utilization of these aquatic plants for the bioremediation of contaminated waters. The review is primarily focused on the specific capabilities of aquatic plants and as an important tool in phytotechnologies in the management of contaminants in aquatic environment.