2001 年 49 巻 4 号 p. 517-518
Efficiency of domestic sewage disposal water on the growth of Heterosigma akashiwo during the early stage of red tide formation was tested under three treatments, namely, (1) domestic sewage disposal water laid on filtered sea water, (2) mixture of domestic sewage disposal water and filtered sea water, and (3) distilled water laid on filtered sea water. Culture was continued for 4 days and repeated three times. H. akashiwo cells collected in sampling area were used as seed for the first inoculation, and H, akashiwo cells which grew in the treatment of sewage disposal water laid on filtered sea water were used for the second and third inoculation. In the treatment (1), cell density increased during the culture period. In the treatment (2), cell density increased during the first 2 to 3 days and kept its density after that. In the treatment(3), cell density increased for 2 days after initiation of culture but decreased rapidly as time elapsed. On the base of those results, there is a possibility that the cell density continues to increase when domestic sewage disposal water is supplied.