The influence of aluminum on the cell-size distribution of two green algae

Abstract

Cell-size distribution of batch cultures of two green algae Monoraphidium and Stichococcus were studied in relation to aluminium exposure. The cell size of Monoraphidium was more differentiated than that of Stichoccus. The distributions changed during the growth period but differed between the two algal species; Monorphidium appeared bimodal before cell division, whereas Stichococcus showed a one-peak distribution pattern. Changes in mean cell size for the two algal populations were similar during growth in batch cultures, the cells grew larger before division. Mean cell size decreased during the logarithmic growth phase; during the stationary growth phase a slight increase reappeared. Both species displayed cell decomposition when exposed to aluminum. The surviving cells grew larger than the control cells when aluminum was added to the medium. The effects of aluminum oncentration on cell size differed during the growth phases for the two algal cultures. The algal populations seemed to be most sensitive during the lag and the early logarithmic growth phases.