Abstract:Four emerged Macrophytes, Sagittaria trifolia, Echinodorus berteroi, Acorus calamus and Phragmites australis, were cultured with synthetic wastewater in phytotron hydroponic system. The eco-physiological characteristics, such as biomass, root length, root lifespan, root porosity, root radial oxygen loss (ROL), photosynthesis and decontamination efficiency of total nitrogen, total phosphorus and COD were compared. The results showed that ROL positive correlated to root porosity, photosynthetic rate and biomass (P<0.05), and significant to root length (P<0.01). The removal rate of TP and COD correlated to photosynthetic rate and ROL, respectively, while the removal rate of TN significantly positive correlated to biomass (P<0.01), and it is negative to root/shoot ratio. Compared with A. calamus and P. australis, S. trifolia and E. berteroi had large biomass, well-developed root system, relatively high physical index in root porosity, ROL and photosynthesis, and a closer or even better decontamination efficiency. It suggested that S. trifolia and E. berteroi might be excellent species for constructing wetlands.
