2020 Volume 36 Pages 1-12
We investigated the diatom flora of a wet grassland on mineral soil on the Ritsumeikan University Biwako-Kusatsu Campus (BKC) in Shiga Prefecture, central Japan. The wetland was originally present in the area, but other wetlands that had been present in other parts of the campus were also transplanted there; the wetland has been maintained by pumped-up ground water as well as by the original spring water. A field survey and sampling took place on 8 November 2013. The water was slightly acidic (pH 5.4–6.1) with variable electrical conductivities (4.8–17.5 mS m−1). Diatom samples were collected from the surfaces of Moliniopsis japonica and Sphagnum palusture. In total, 108 diatom species (including nine unidentified ones) belonging to 30 genera were found, and they were all listed and illustrated. In terms of species richness, the dominant genus was Pinnularia represented by 20 species followed by Eunotia with 12 species. While the generic diatom composition was similar to those in peaty moors in Lake Biwa basin, the species composition was much different. We found some diatoms that are unusual in wetlands around Lake Biwa such as Pinnularia osoresanensis, which has been reported only in strongly acidic waters.
