The effects of diel changes in photosynthetic coefficients and depth of Planktothrix rubescens on the daily integral of photosynthesis in Lake ZurichInfluence of the Mixing Regime on Algal Photosynthetic Performance in Laboratory Scale EnclosuresChanges in photosynthetic properties measured by oxygen evolution and variable chlorophyll fluorescence in a simulated entrainment experiment with the cyanobacterium Planktothrix rubescens