Pontederia cordata L.was hydroponic cultivated in two purifying-tanks（with and without aeration） with same planting density of 13（plants/m2 water area）

to investigate physiological characteristics of the plants and main physical and chemical characteristics of the effluents.The physiological responses of P.cordata L.and the nitrogen（N） and phosphorus（P） variation of polluted water under long-term aeration were analyzed.Another tank without plant was prepared for control（CK）.Results showed aeration affected physiological characteristics of the plants.The lengths of the roots

stems and leaves of the plants in the non aeration exceeded the aeration by 12.67 cm

18.30 cm and 2.33 cm

respectively.POD and CAT activities of plants roots at the aeration status exceeded the non aeration by 0.028 3 U/（g·min） and 0.179 0 mg/（g·min）

while Chla

Chlb and SP contents of the leaves were lower than the non aeration by decreasing 0.314 2 mg/g

0.118 4 mg/g and 15.75 mg/g.Aeration influenced N and P accumulations and the biomass of the plants.The N and P contents of root tissues were higher with the non aeration than those with aeration by increasing 5.04 g/kg and 1.03 g/kg

respectively.Similarly

The N and P contents increased 6.57 g/kg and 1.32 g/kg for stem tissues

8.67 g/kg and 1.46 g/kg for leaves.Biomass of roots

stems and leaves with aeration was lower than that without aeration by decreasing 3.03（per plant）

2.32（per plant） and 0.74 g（per plant）.Aeration affected the N and P concentrations of polluted water.TN and NH+4-N concentrations at the aeration were lower by declining 11.22 mg/L and 7.81 mg/L

while TP and soluble P concentrations exceeded those with the non aeration by 0.089 mg/L and 0.044 mg/L.