Summary of trait-based tests for community assembly at each sampling date of our study period: a) first principal component of Cytobuoy-derived phytoplankton traits (Table S1); b) size of phytoplankton particles; c) Chl-a particle fill; d) phycocyanin particle Fill (see Methods and Table 2).

<p>Dots indicate statistically significant deviations from null-model expectations (Wilcoxon p-value >0.05): red = SDNDr (even spacing of traits); green and blue = distribution range and mean, respectively (environmental filtering). The grey shaded area emphasizes the period of herbivore ciliate grazing (phase 2 in the text).