USE OF VEGETATED WETLAND TO REMOVE NITROGEN FROM DOMESTIC SEWAGE THROUGH AMMONIA VOLATILIZATION

Direct disposal of raw municipal sewage for crop irrigation without an y prior treatment revealed evidence of its rich ammonium-nitrogen cont ent. The present study revealed significantly higher (x 2.8 times) nit rogen loss through ammonia volatilization in the vegetated wetland (fl ux, 113 mg ammonia/m2 surface/day) because of higher flood water ammon ium-N concentration compared to the wetland area without any macrophyt es (nux, 40 mg ammonia/m2 surface/day). The amount of ammonia loss and nitrate-N status in sewage irrigated soil without any crop was 1.5 ti mes higher (nux, 89) than the soil with the crop (flux 57). Absence of rhizospheric factor and nitrate-N uptake enhanced both the processes at the former site. The overall study pointed that vegetated aquatic s ystem provides a better treatment avenue for nitrogen removal.