Abstract
The diatom flora and some environmental conditions of diatom habitats were studied in Kushiro mire, Hokkaido, Japan. Sampling sites were located in various types of higher plant vegetation (i. e. alder swamp, sedge fen, reed fen and sphagnum bog). Water temperatures varied little among sampling sites. The water in sphagnum bog had much lower pH values. DO (dissolved oxygen) varied from site to site. There were some sampling sites in sedge fen and alder swamp that were more shaded than those in other higher plant vegetation. A total of 121 species of diatoms were collected from these sampling sites. They were mainly benthic diatoms. The numbers of species collected at each sampling site were from 13 to 45 species. Smaller numbers of species were collected in sphagnum bog than in other higher plant vegetation. This may be due to lower pH values of waters in sphagnum bog. From the dendrogram of the cluster analysis, on the whole, diatom communities that were observed in the same type of higher plant vegetation were classified into similar groups.
