A comparison of two aquatic plants purifying the low-concentration polluted river water in the bio-rack wetland

A comparative study of the purifying efficiency between two plant species was conducted in the bio-rack wetlands for low-concentration polluted river water treatment in order to evaluate the purified effects of different wetland plants. When TN, NH3-N, NO3-N, TP, and COD concentrations of the influent were 1.42–5.92 mg/L, 0.153–2.04 mg/L, 0.392–1.966 mg/L, 0.074–0.211 mg/L and 5.38–12.73 mg/L, respectively, the average removal efficiencies of wetland planted with Thalia dealbata and Acorus calamus were 67.36% and 58.42%, 63.31% and 50.13%, 71.69% and 54.73%, 80.62% and 70.01%, and 24.03% and 19.19%. It indicated that the bio-rack wetland was an efficient approach for nutrient treatment, and removal efficiencies were influenced by plant species. Thalia dealbata showed higher contaminant removal rate than that of Acorus calamus, indicating Thalia dealbata was suitable for selected plant to purify low-concentration polluted river water in the bio-rack system