Abstract:

Pot experiments were conducted to screen hydrophyte plant species for high uptake potentials of N and P. The plants including three kinds of emerged plants, namely Thalia dealbata, Iris tectorum, Canna indica, and three kinds of floated plants, namely Ludwigia peploides, Myriophyllum spicatum, Pistia stratiotes. The results showed that: among all these species, the dry weight, uptakes of N and P, and the highest abilities of removal of N and P from water of Thalia dealbata and Pistia stratiotes were found in 15 d pot experiments. Furthermore, when combining emerged plants with floated plants into a pot experiment, the increase in dry weight, and the abilities of removal of N and P of emerged plant were higher than those of floated plants. Combination of Thalia dealbata with Pistia stratiotes could remove 90.7% of P and 97.9% of N during 15 d growth period. Thus, these two spices could be recommended as ideal plants in remediation of N and P polluted waters．

Key words: hydrophyte species, phosphorus, nitrogen, removal potential