抄録
The distribution of dormant cells of the red tide flagellate Heterosigma akashiwo (Raphidophyceae) was investigated by the extinction dilution method in sediments of northern Hiroshima Bay where red tides of H. akashiwo occur almost every year. Densities of the dormant cells in sediment samples ranged from 56 to 5, 950 cells·cm-3 wet sediment in April 1987, and from 56 to 29, 300 cells·cm-3 in March 1989. No significant relationship was observed between the number of dormant cells of H. akashiwo and mud content of sediment sample. High density stations of the dormant cells in sediments appeared to coincide with the areas with high concentrations of vegetative cells in water columns during the red tide season.
