Benthic diatom flora of intertidal sediment in Tokyo Bay, Japan

Abstract

We investigated the benthic diatom flora of the intertidal shore in Tokyo Bay, Japan. Sediment samples were collected from 15 intertidal flats and beaches during several ebb tides in May 2010. The salinity ranged from 10.6 to 30.5. A total of 88 taxa occurred from the 15 sampling sites. For each site, the number of species identified ranged from 9 to 33, with the exception of one site that contained the coarse-grained sediment and at which diatoms were not observed. The dominant taxa (those with relative abundances of more than 10%) were mainly species of Navicula and Amphora. The species observed at the largest number of sites was Navicula gregaria; the second most widespread were Haslea feriarum and Fallacia cf. teneroides. Most of the species in Tokyo Bay are cosmopolitan, thus, benthic diatom flora in intertidal flat would be affected by specific environments of intertidal flats, such as drying and drastic changes of temperature and salinity by the tidal fluctuation.