Photoinhibition of colonial and unicellular Microcystis cells in a summer bloom in Lake Taihu

摘要: To evaluate the photoinhibition of colonial and unicellular cells Microcystis aeruginosa under natural conditions, maximum effective quantum yields photosystem II were measured from variable chlorophyll a fluorescence in samples Lake Taihu during summer bloom June 19 to 21, 2006. Diurnal changes incubated immediately below surface clear bottles for 30 min situ conditions measured. At solar noon three days, mean values yield (F v/F m) (ΔF/F m′) m = 0.15, ΔF/F m′ = 0.10) lower than those m = 0.25, m′ = 0.15). For samples, F m m′ at on days 0.30, 0.25, 0.29; 0.24, 0.21, 0.22) also higher 0.26, 0.18, 0.25; 0.15, 0.11, 0.14). The results indicate that colony formation has protective effect by reducing occurrence high light intensities.