Floating wetland treatment an ecological approach for the treatment of water and wastewater – A review

Abstract

The demand for water increases day by day due to population growth; on the other hand, water quality is declining globally due to rapid industrialisation and climate change. The surface water sources such as ponds, lakes, rivers, and reservoirs are being polluted and have lost their ecological functions. Floating wetland treatment (FWT) is an emerging natural method for treating surface water bodies and restoring their ecological processes. This study attempted to collect and summarise literature to give an insight into the design, construction, applications, macrophytes, substrates, and pollutant removal efficiency of FWT. The pollutant removal mechanism of FWT mainly depends on the hydrophytes grown on a floating raft with substrates attached for the growth of microorganisms. This paper also reviews the performance of floating wetlands planted with different hydrophytes, growth mediums, and floating rafts in mesocosms, in-situ, and lab-scale environments. Several pollutants were also reviewed, including TN, TP, TSS, BOD, COD, and ammonium nitrogen removal efficiency between plant species and growth medium. This review found that combining native plant species with different substrates under varying climatic conditions has improved the performance of FWT. Many studies recommend further research on FWT by adopting other macrophytes and substrates to improve the removal efficiency of pollutants in water and wastewater.