Fig. 2.
Effect of the acidification by HCl (a–c) and the ocean acidification conditions by elevating pCO2 (d–f) on the changes in photosynthetic O2 evolution activity of the coccolithophore E. huxleyi. Experimental conditions for acclimation (indicated in the figure) were same as shown in Fig. 1. The rate of photosynthetic O2 evolution was determined using a Clark-type O2 electrode at the light intensity of 270 μmol photons m−2 s−1 and 25 °C which are the optimum conditions. The values are average of three experiments (n = 3)