Figure 2. Abundance of protists observed in: (A) Trial 1 with three microplastic addition treatments (i.e., 0, 1 and 10 mg g-1) up to 14 days after the onset of the trial, and; (B) Trial 2 with two microplastic addition treatments (i.e., 0, and 3 mg g-1) up to 21 days after the onset of the trial. Each time point per treatment represents the mean of protists (n=10). Error bars represent the standard error of the mean.