抄録
The distributions of modern benthic foraminiferal assemblages were investigated in Ise and Mikawa bays, Japan, using surface sediments collected in September 2007. Forty seven species belonging to 40 genera were identified from Ise and Mikawa bays. Agglutinated species were dominant in the inner part of Ise and Mikawa bays, while calcareous species were dominant in the central part of Ise Bay. Significant shifts of assemblages were found in comparison with the distribution from surface sediments collected in 1940 from Ise Bay; calcareous species were replaced with agglutinated species in the inner part and the composition of calcareous species had changed completely in the central part. These results suggest that the present bottom environments are more eutrophic and anoxic than they were 67 years ago. Indicator species also suggested that Ise Bay is presently more eutrophic and anoxic than Mikawa Bay. A comparative study of distributions in Tokyo and Osaka bays demonstrated several similarities, while regional characteristic also were found there.
