An experiment on the effects of nitrogen content on artificial sewage purification in modelling stabilization pond systems has been carried out in laboratory during spring to summer in 1988 and 1989. The results obtained indicate that when TP concentrations are kept at 7mg/l and TN concentrations are varied from 77.4, 44.4, 24.8 to 13.5 mg/l in raw sewage, the removal rates of TP, BOD and LAS in the stabilization pond are decreased with TN concentration increasing, but the removal rates of TN appear an oppo...