Diversity of bacterial community during spring phytoplankton blooms in the central Yellow Sea.

Bacterial community diversity and the effects of environmental factors on bacterial community composition during 2 spring phytoplankton blooms in the central Yellow Sea were investigated by using denaturing gradient gel electrophoresis (DGGE) and multivariate statistical analysis. The Shannon-Weaver indices (H') of bacterial diversity from samples at station B23 were higher than those at station B20. Cluster analysis based on DGGE band patterns indicated temporal variations of bacterial community at the 2 bloom stations but a vertical distribution pattern only at station B20. The predominant bacterial groups were affiliated with Alphaproteobacteria, Gammaproteobacteria, Cytophaga-Flavobacterium-Bacteroides, Deltaproteobacteria, and Actinobacteria. The effects of environmental factors on bacterial community were analyzed by canonical correspondence analysis. Bacterial community structures were significantly affected by silicate at station B20 and by Paralia sulcata and Heterocapsa spp. at station B23. From the results, phytoplankton species composition had a significant effect on bacterial community structure during phytoplankton blooms in the central Yellow Sea.