Research on Nitrogen Removal and Microorganism in a Subsurface Flow Constructed Wetland System in Sihong County

Experiments in monitoring the removal of organic material and nitrogen and determining the amounts of microorganism at different sites in the subsurface flow constructed wetland in Sihong county were performed. The results show that the removal of CODcr agrees with the kinetic equation of a first order reaction. The removal of pollutants varies with different seasons. The removal rates of CODCr, NH3-N, TN in the spring are 15%–23% higher than those in the autumn. The amount of ammonifier is larger than that of denitrifying bacteria and the amount of denitrifying bacteria is larger than that of nitrosomonas. The amount of bacteria around the plant roots is larger than that on the surface of the packing medium. No apparent change is observed for the amount of denitrifying bacteria and nitrosomonas between spring and autumn.