Investigation and analysis on characteristics of microalgae community in prawn ponds

Based on the analysis of the microalgae samples collected from intensive higher-place prawn, semi-intensive earthen ponds and their intake canal in Zhanjiang, China in October 2005 and April 2006, a preliminary study was carried out on the microalgae community. The results showed that a total of 47 species of microalgae was identified in the culture ponds and intake canal, 28 species identified in spring and 21 species in autumn. The dominant species were Oscillatoria sp. and Cryptomonas erosa Ehr. The average variations of diversity (H′) were 2.29, 1.42 and 1.12 in Dongnan semi-intensive earthen ponds, Dongnan intensive higher-place ponds and Dongshan semi-intensive earthen ponds respectively in spring, 2.14 in intensive higher-place ponds and 1.62 in Dongshan semi-intensive earthen ponds in autumn, and it varied from 0.92 to 3.73 in the intake canal in the two season samplings. Average consistency of microalgae in autumn was higher than that of ponds in spring.