Ostracodes from Aomori Bay, Aomori Prefecture, Northeast Honshu, Japan
Fifty-eight species distributed among 33 genera of ostracodes were discriminated from the sediment samples collected from 36 of the 38 stations in the eastern half of Aomori Bay (Table 1, figs. 1, 2). Among them one genus and 13 species are described as new to science. Clustering analyses of the fauna by the correlation coefficient based upon frequencies for similarity of the ostracode species association (R-mode) and station similarity (Q-mode) served to delineate the distributional patterns both of biotopes and species associations. The clustering was made by the weighted variable group method with simple arithmetic average. The most important environmental factor controlling the distribution of the ostracodes might be indicated more clearly by the second factor loadings calculated for Q-mode (fig. 6). The distribution of the ostracode fauna of Aomori Bay is affected by the inflow current from the open sea, depending more effectively upon the geometric condition than the hydrography. From the distribution of "a" of Motomura's Law logY+aX=b, two distinct communities may by suggested : one prevails dominantly in the central part (outer part of the studied area) of the bay and the other in the littoral and/or phytophagous conditions (fig. 7). On the other hand, relatively dense covering of species association 7 on the outer near shore area might suggest another possible independent community that is particular to such an intermediate area.
- The science reports of the Tohoku University. Second series, Geology = 東北大学理科報告. 地質学
The science reports of the Tohoku University. Second series, Geology = 東北大学理科報告. 地質学 43 (1), 59-A15, 1971-10-20