Nitrogen and Phosphorus Absorption Capacity of Phragmites australis in Constructed Pond-Wetland System for Reclaimed Water Treatment

A typical area,Tianjin Airport Industrial Park with reclaimed water supplement for river system was selected as a case study to explore phosphorus and nitrogen absorptive capacity in different components of Phragmites australis in a constructed pond-wetland combination system during one growing season.Results showed that mass fractions for nitrogen and phosphorus in different tissues were(1.17±0.82)%,(0.067±0.057)% respectively,and it was the highest in panicles while the lowest in stems of Phragmites australis.Mass fraction of nitrogen and phosphorus varied significantly from habitats and ranged between 0.22% and 2.34%,while phosphorus ranged among 0.012% and 0.23%.Aboveground biomass(119.37±62.25) kg/m2 in constructed pond-wetland system was obviously higher than that in natural condition(19.08±5.73) kg/m2,and cumulative ability of Phragmites australis ground components to nitrogen and phosphorus was much higher(4.10 and 5.20 times respectively) than that of its underground components,which indicated the supply of reclaimed water might enhance the primary productivity of Phragmites australis.