Biomass of (a) green algae and (b) cyanobacteria (in μg Chl a cm⁻²) before the flow event (=day 0 of the experiment; indicated as “Pre”), and after the flood event (day 7 of the experiment) in control (C) and flow treatments (F). The box displays the first and third quartile, the band inside the box represents the median; the whiskers denote minimum and maximum; data more than 1.5 interquartile range below the first or above the third quartile, were treated as outliers (o).