Constructed wetland: multi-functional benefits of an ecological engineered system

Introduction and aim: Constructed wetlands (CWs) are engineered systems inspired by natural wetlands and commonly used for decentralized wastewater treatment. Although their efficiency in pollutant removal is well recognized, other ecosystem services they provide are often overlooked. This work highlights these broader multifunctional benefits through a real-scale horizontal subsurface flow CW (HSSF-CW) operating at a tourism facility in northern Portugal. Results and discussion: System has shown stable long-term operation, providing a reliable basis to explore additional ecosystem services beyond conventional wastewater treatment. Carbon sequestration is being assessed through biomass accumulation and carbon retention in the substrate. Energy recovery is under evaluation using microbial fuel cell integration Harvested plant biomass is being tested for composting and soil amendment, supporting nutrient recycling within the system. The treated effluent demonstrates potential for safe water reuse in irrigation, promoting circular water use on site. Treatment performance is being enhanced using photocatalytic and nanostructured filter modules. Future research would be advanced system optimization and modeling. Conclusion: Recognizing other broader functions of CWs is essential to repositioning them as more than just wastewater treatment technology but rather as multifunctional ecosystem systems that they are.