Improving low-temperature performance of surface flow constructed wetlands using Potamogeton crispus L. plant.

In this study, enhanced organics and nitrogen removal efficiency in SFCWs by different submerged plants for polluted river water treatment under cold temperature was evaluated. High average removal efficiencies of COD (92.45%), NH4(+)-N (93.70%) and TN (55.62%) were achieved in experimental SFCWs with Potamogeton crispus compared with SFCWs with other plants. SFCWs with underground Phragmites australis root also presented better performance than the unplanted systems, indicating its positive role of contamination removal in winter. The results of this study indicated SFCWs with hardy submerged plant P. crispus could be a more effective and sustainable strategy for removing organics and nitrogen in shallow nutrient enriched river water ecosystems under cold climate.