Organic and Nutrients Removal by 5 Aquatic Plants in Simulated Constructed Wetland

In order to study the contaminant removal characteristics of constructed wetlands (CWs) under high loadings, the performance of CWs planted with Arrowhead, Alisma, Monochoria korsakowii, Thalia dealbata and Oenan the were investigated, respectively, to determine the effects of plants in contaminant removal and for wetland plant selection. The experiment was conducted by sequencing batch feed, with the initial ammonia nitrogen(NH₄⁺-N), total phosphorus(TP)and chemical oxygen demand (COD) concentration of 37.7mg/L, 2.1 mg/L and 71.6 mg/L, respectively. The results showed that, for TP removal, the highest removal efficiency of 79.01% was acquired in Arrowhead treatment, while other plants treatment showed little difference from unplanted control. For NH₄⁺-N removal, all planted treatments showed superior removal rates than unplanted control, the highest removal rate of 63.67% was also acquired in Arrowhead treatment. For the COD removal, the removal rate of treatments all reached 40%-70% and planted treatments performed better than the control treatment, especially for Arrowhead. Generally speaking, Arrowhead was the best plant for CWs under high loadings. Plant factors played an important role in contaminant removal processes of CWs.