- 四日市大学環境情報論集 (ISSN:13444883)
- vol.3, no.1, pp.85-104, 1999-09-30
Daito Islands, locating about 360km east of Okinawa, are raised atoll reefs consisted of marginal hills and central lowland. The islands would be more raised in the last ice-age (Hypsithermal) than at present, and many ponds in the lagoon are considered to be originated from dolines or uvalas formed in that age. A limnological investigation was made in the latter part of February, 1998,on the 11 uvalas ponds and 2 doline ponds. 124 species of Phytoplankton and 51 species of Zooplankton were found. In regard to the feature of plankton faund and flora as well as the water analysis, it may be inferable that Hosaku-ike, Kamo-ike, Tukimi-ike, Mizukumi-ike, Shiomizu-ike, Miharasi-ike, Tansui-ike, Kasumi-ike, Asahi-ike, Hyoutan-ike, Oo-ike, Shinobu-ike, and Obi-ike are Eutrophic lake Type.