Floating phytoremediation system by planting Canna generalis for dual purposes of purification of piggery wastewater and nursery

A floating phytoremediation system made by polyfoam plate was used to plant Canna generalis in order to study the effects of the purification of N, P and COD_Cr of piggery wastewater and the possibility of the system used as a nursery for rapid asexual reproduction of the plant. The results showed that Canna generalis could grow well, and had high biomass and huge roots. The purification effects of total nitrogen (TN), total phosphate (P) and COD_Cr of piggery wastewater were significant, with the removal rate up to 90%. The tillering numbers per plant were 2.5 after 35 days of growth, the total tillering numbers per plant per year could be up to 20 to 25. That was a good method for the use of nursery.