沖部における付着珪藻群集の類似度に基づく琵琶湖南湖盆の水域区分

Abstract

The composition of the off-shore epilithic diatom communities was studied in the southern basin of Lake Biwa during the period from April to July 1976.The species Achnanthes minutissima, Synedra sp., Cymbella turgidula, Cymbella ventricosa, Synedra rumpens var. familiaris, Cymbella tumida, Synedra delicatissima were generally prominent. The results of cluster analysis using the similarity index on epilithic diatom communities were shown in Fig. 2 and Fig. 3. Fig. 3 was mapped out by the prominent species above mentioned. The variation of the diatom communities at each station was arranged in Fig. 4, which might be closely related to flow of water masses e. g., inflow from the northern basin, polluted inflow from the eastern vicinity and domestic or industrial waste water from cities, villages and their vicinity.