Figure 7From: Vertical migration of phytoplankton in coastal waters with different UVR transparencyThe rETR of phytoplankton. rETR of phytoplankton is plotted versus irradiance (n = 3 of the first 3 days of the spring campaign) determined in situ before sunrise (completed before 5:15 a.m.) at study site Helgoland. The light saturation of photosynthesis (EK, quotient of Pmax and alpha) was calculated to be around 219 μmol photons m-2 s-1.Back to article page