Fig. 4.

Photosynthetic activity of A. platensis (a) and R. sphaeroides (b) and combined activity from a single beam of ‘sunlight’ (c). In (a) and (b), activities are expressed per unit of light intensity; the reflected and transmitted intensities were, 6.2 and 3.8 W/m², respectively. In (c), the stacked dark and pale bars represent the combined activities of A. platensis under transmitted sunlight (dark) and R. sphaeroides under reflected sunlight (pale), relative to either singly under complete sunlight (shown as a white bar for comparison). a Shows means and standard errors from four independent experiments with and without the dichroic mirror each including 6 replicates. b Shows four independent experiments with the mirror and three in ‘sunlight’, each including 4 replicates. ΔOD: increase in OD₆₆₀