FIG. 3.

Activities of the four hydrolytic ectoenzymes measured during phytoplankton bloom experiment 1 (left panels) and cell-specific hydrolysis rates obtained by normalizing enzyme activities to bacterial abundance (right panels). Enzyme activity is shown in micromoles per liter per hour, and the hydrolysis rate is shown in femtomoles per cell per hour. The insert graph shows alkaline phosphatase activities (APA) normalized to total bacterial and algal biomass (expressed as micromoles per microgram of C per liter). Microcosms are labeled as described in the legend to Fig. 2. Values are the means ± standard deviations (error bars) for samples from duplicate subsamples. AMA, aminopeptidase activity; d, days.