Community Structure of Zooplankton and Assessment of Water Quality in Weishan Lake

The community structure of zooplankton was surveyed four times in Weishan Lake from April of 2010 to December of2010. Totally, 77 species of zooplankton including 18 species of protozoa, 45 species of rotifers, 8 species of cladocera and 6 species of copepods were found, the maximal zooplankton species(48)in summer and autumn and the minimal(43)in spring and winter.There was zooplankton density of 0.75×103ind.·L-1in autumn and 0.71×103ind.·L-1in winter, the highest density(1.26×103ind.·L-1)in spring and the lowest(0.47×103ind.·L-1)in summer. The biomass of zooplankton was found 2.41 mg·L-1 in spring and 4.03 mg·L-1in autumn, the maximum(6.69mg·L-1)in summer and the minimum(1.52mg·L-1)in winter. The Shannon-Weiner index was varied from 1.74 to 2.15 while the Pielou index was changed from 0.48 to 0.74. The water quality in Weishan Lake was comprehensively evaluated as moderate pollution.