Ecological Restoration by a Multistage Floating-Bed System in a Eutrophic Urban River, China

By constructing a multistage floating-bed system by combination of macrophytes, aquatic animals and aquamats ecobase for ecolgical restoration in a eutrophic urban river, the improvement of water quality and the dynamic variation of phytoplankton was investigated. The results showed that the average removal rates were 9.85%, 15.86%, 24.47% and 12.75%, respectively. phytoplankton quantity was decreased by 22.82×104ind./L and Shannon-Weiner Index was increased by 0.11 averagely, after the restoration work in the demonstration area comparing to control area. The negative correlation between Shannon-Weiner Index of phytoplankton and TN(-0.77, P<0.01) showed that multistage system might effect phytoplankton indirectly through removing nutrients from river, which indicated that the employment of ecological restoration technology of multistage floating-bed system was effective in raising the ecological recovery efficiency of polluted water bodies.