Bioremediation of Nutrients and Heavy Metals in Watersheds: The Role of Floating Treatment Wetlands

Floating treatment wetlands (FTWs) are engineered systems that use floating platforms planted with aquatic vegetation to treat polluted water such as stormwater, agricultural runoff and wastewater. FTWs have emerged as promising and environmentally sustainable solutions for water purification. This review synthesized current knowledge on FTWs design, plant selection, and performance evaluation. It highlights key factors influencing nutrient and heavy metal removal, including hydraulic retention time, mat thickness, and plant species. Recent findings on the roles of root architecture, microbial interactions, and seasonal variability in treatment efficiency are also discussed. Additionally, the review explores advanced analytical methods for monitoring water quality and assessing plant growth and contaminant uptake. Case studies from both laboratory and field-scale experiments illustrate how variation in FTW configurations impacts pollutant removal efficiency. The review concludes by identifying critical research gaps, including the need for standardized monitoring protocols, strategies to enhance long-term performance, and the integration of FTWs with complementary treatment technologies to improve effectiveness across diverse aquatic environments.