Influence of ecological floating bed on density and biodiversity of planktonic algae in winter

To study the operation effect of ecological floating bed in winter, floating bed restoration project of Bailianjing River in Expo Sites was selected as objective. Influence of ecological floating bed in winter on density and biodiversity of planktonic algae investigated. The results showed that density of planktonic algae increased every month during the experiment period, and density of planktonic algae in control area was higher than that in floating bed area. Community structure of planktonic algae density between floating bed area and control area were obviously different. Bacillariophyta was the dominant species in the floating bed area, whereas chlorophyta was the dominant species in the control area. Meanwhile, dominant degree of Cyclotella bodanic and Oscillatoria subtillissima both decreased. In addition, Shannon-Wiener diversity index in floating bed area were obviously higher than that in the control area. All of these results indicated that though the temperature was very low in winter and most of the aquatic plants were grown slowly, the ecological floating bed could influence the density and biodiversity of planktonic algae and improve water quality to a certain extent.