Figure 2.
Phymatolithon lusitanicum. Photosynthesis, respiration, and calcification after 11 months of exposure at three different CO 2 levels (400, 550 and 750 μatm) (a) Dark respiration and net photosynthesis as a function of light (8, 45, 195, and 450 μmol photons m−2 s−1), (b) net calcification as a function of light (0, 8, 45, 195, and 450 μmol photons m−2 s−1) results calculated using the total alkalinity anomaly technique, and (c) correlation of net photosynthesis and light calcification at 200 μmol photons m−2 s−1 under control and high CO 2 conditions. Different letters indicate significant differences with CO 2 and irradiance. Values are expressed as mean ± standard error (n = 4)