The methods of Protargol staining and sedimental counting were adopted in quantitative and qualitative analyses of planktonic ciliates from Dayawan Bay Based upon the structural parameters of the planktonic ciliates

some characteristics of planktonic ciliate communities are shown as follows: the planktonic ciliate communities were composed of 9 to 29 species of ciliates; the abundances were from 2 000 to 13 400 ind/L; the dominant species of the communities were Strombidium ventropinnum and Strombidium strobila ; and the community biodiversity indices were from 2 713 2 to 4 233 9 The influences of cooling water from Dayawan Nuclear Power Plant on the planktonic ciliate communities were analyzed as well.