Nitrogen transformation in horizontal subsurface flow constructed wetlands II: Effect of biofilm

On the other hand, biofilm activities had significant influence on ammonia-nitrogen and nitrate-nitrogen transformation. The developed model output indicates that the effluent ammonia concentration was 2 gN/m2, but in absence of biofilm the effluent ammonia concentration increases to 3.5 gN/m2. Statistical analysis indicates that the mean average nitrogen-nitrogen in the effluent was 0.71 gN/m2 when aggregate-biofilm was considered, but increased to 0.83 gN/m2 when it was not considered.