A Comparision Of Phytoplankton Communities In Restored And Un-restored Areas In Huizhou West Lake

The investgations of phytoplankton community structures in restored area (Nanhu) and un-restored area(Pinghu) of Huizhou West Lake were carried out to study the effects of lake restoration on the phytoplankton community, from February to November,2010. Results showed:(1) The diversity indices of phytoplankton in Nanhu was higher than that of Pinghu, the maximum values were 0.88 (nit) in February and 1.93 (nit) in August, respectively while the minimum values were in May and November in both lakes. (2) Seasonal variation of dominant phytoplankton species were as follows: Cryptophyta-Chlorophyta(Scenedesmus quadricuda)-Pyrrophyta(Peridinium sp.) in Nanhu, however, it was dominant absolutly by Cyanophyta in Pinghu, which did not change significantly all year round; the dominant species were Merismipedia sp. and limnolothix sp.. (3) The mean biomass and cell densities were higher in Pinghu than that in Nanhu. Which idicates that macrophytes restoration can not only decrease the biomass of phytoplankton, but also change the phytoplankton community, increase the diversity indices of phytoplankton, thus improve the water quality.