Abstract: A pilot scale shale/slag-filled subsurface flow constructed wetland was used in the tertiary treatment of urban wastewater. The results showed that under the condition of average hydraulic loading rate being 0.32 m·d^-1 and when the average concentrations of COD_cr, TN and TP in the influent were 33.9, 15.1 and 1.57 mg·L^-1, respectively, the average concentration of COD_cr in the effluent was 13.6 mg·L^-1, its removal rate was 60%, and the first-order areal rate constant K_A was 0.3 m·d^-1. The removal of COD_cr was less affected by perature. The TN concentration in the effluent fluctuated from 5.4 to 14.3 mg·L^-1, K_A fluctuated from 0.09 to 0.31 m·d^-1, and the N removal was negatively affected by lower temperature while positively affected by higher NO_x-N/TN ratio and longer operation time. At steady stage, the average concentration of TP in the effluent was 0.6 mg·L^-1, its removal rate was 50%, andK_A was 0.26 m·d^-1. Temperature had less effect on TP removal.

Key words: Plant-culture system, Mangrove, Bacteria ecology