Riparian constructed wetlands have been promoted as a means of reducing nutrient inputs from nonpoint pollution and river pollution.Riparian constructed wetlands have combined the treatment principles of both natural riparian wetlands and constructed wetlands.A three dimensional numerical model was developed for modeling TP transport in cascaded riparian constructed wetlands.The effects of plant roots and filler to TP transport and removal efficiency were discussed from the aspects of the flow fields

TP concentration fields and the fate of TP.The removal efficiencies of the riparian constructed wetlands with plants are higher than the corresponding riparian constructed wetlands without plants.The removal efficiencies of the riparian constructed wetlands with pisolite（degradation parameter and conductivity parameter were relatively larger） are a little higher than the corresponding riparian constructed wetlands without pisolite.