Control effects of aquatic plants on eutrophication in reclaimed water river-lake

Reclaimed water contains lots of nitrogen and phosphorus, which made the environment of water reuse district face a certain pollution risk. Aquatic plants are accepted to become a feasible method for purifying reclaimed water in situ. Based on this, four aquatic plants, Scripus validus, Typha angustifolia (emergent aquatic plants), Water hyacinth (submersed plant) and Potamogeton Crispus L (submerged plant) were chosen for purification effect of TN and TP in reclaimed water with simulated experiments, which are commonly planted in Beijing at present. The results showed that: The optimal time for TN purified in overlying water was concentrated in the second period (incubation time 60-90 d), while TP in the third (incubation time 90-120 d). The emergent aquatic plants had the best removal efficiency for TN and TP in interstitial water and sediment. The emergent aquatic plant itself had better accumulation effect of TN and TP with nice landscape effect, particularly for the compound type. And it could gain the high removal efficiency for the pollutants with harvest timely. The research can provide a reference for constructing artificial wetlands and choosing the aquatic plants in reclaimed water reusing for ecological water in city rivers and lakes.