Recent developments in aquatic macrophytes for environmental pollution control: A case study on heavy metal removal from lake water and agricultural return wastewater with the use of duckweed (Lemnacea)

Abstract

Aquatic macrophytes are a remarkable method among the phytoremediation processes and treatment techniques of sediment, water, and wastewater, which have the potential to accumulate high heavy metal concentrations. They play an important role in wetland technologies as they can bioaccumulate heavy metals with their indirect/direct absorption mechanism. Since macrophytes have the ability to transfer toxic metals found in sediments and water at varying levels from root to shoots, they can provide a sustainable cycle in aquatic ecosystems. Duckweed (Lemnacea) is one of the plants used for this purpose and it is based on the principle of growing plants together with microorganisms in these systems. In this sense, this chapter discusses firstly review the recent developments in aquatic macrophytes for environmental pollution control, then biosorption and bioaccumulation mechanisms of heavy metals by macrophytes, factors affecting bioremediation with macrophytes, defences of aquatic macrophytes to the presence of heavy metals in aquatic environments, benefits using macrophytes as bioindicators in determining, and monitoring water pollution and waste management and disposal. Finally, the removal efficiency of heavy metal pollution in lake waters and agricultural activity return waters carried out in this area with duckweed (Lemna Minor), which is widely found in the lake flora, was evaluated within the scope of a case study. According to results from this study, duckweed (L. Minor) was found an effective and low-cost aqua macrophytes for this region for removing heavy metals from surface water. © 2022 Elsevier Inc. All rights reserved.