Aquatic plants can utilize large amounts of
nitrogen and phosphorus, and the aboveground biomass could be
harvested to remove these nutrients from wastewater ultimately.
In addition, the harvested aquatic plants also could be used to
generate valuable products, such as biogas, biofertilizer and biomaterial
(Singhal and Rai, 2003). At present, at least three approaches
are being used to remove nitrogen and phosphorus through utilization
of aquatic plants, which are macrophytes pond systems with
free-floating plants, constructed wetlands with emergent plants
and rhizofiltration system of floating bed (Li et al., 2007).