Journal of the Faculty of Fisheries and Animal Husbandry, Hiroshima University Volume 6 Issue 2
1966-12-20 発行


A study on the vertical distribution of vibrio parahaemolyticus in sea bottom
Asakawa, Suezo
The present study was undertaken to investigate the distribution of Vibrio parahaemolyticus within columns of marine sediments in relation to the distance from the water-bottom interface. Both the laboratory experiment employing the 'artificial sea bottom' and the field survey in nearshore waters were conducted. The biotype 1 organisms of the bacteria were found only in the upper layers of the sediment in the case of sandy bottom, while their occurrence sometimes extended to somewhat deeper layers in the muddy bottom. The biotype 2 organisms inhabited both sandy and muddy bottom, ranging from water-bottom interface to a depth of 10 or 15 cm. It is therefore suspected that the tendency for the biotype 1 organisms to have been detected at high ratios from the sandy bottom, which was reported in the previous papers, was most probably due to the functional deficiency of the employed bottom sampler which was prone to sample the surface layer of sandy bottom and the deeper layers of soft muddy bottom.

It is inferred that the want of nutriments was one of the major factors which precluded the occurrence of the biotype 1 organisms in deeper layers of sandy sea bottom.