How does rising atmospheric CO2 affect marine organisms?

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Interactive Effects of CO2 and Ozone on Soybeans
Reid, C.D. and Fiscus, E.L.  1998.  Effects of elevated [CO2] and/or ozone on limitations to CO2 assimilation in soybean (Glycine max).  Journal of Experimental Botany 18: 885-895.

What was done
The authors grew soybeans for a single season in pots placed in open-top chambers that received either ambient (365 ppm) or elevated (727 ppm) concentrations of atmospheric CO2 and below-ambient (20 ppb) or 1.5 times ambient (74 ppb) levels of ozone, in order to determine the interactive effects of elevated CO2 and ozone on photosynthesis.

What was learned
Elevated CO2 enhanced rates of photosynthesis in the presence or absence of ozone and typically ameliorated the negative effects of ozone on carbon assimilation.  This alleviation of ozone-induced damage probably resulted from the reduced stomatal conductances that were reported in the elevated CO2 x ozone treatment, which were significantly lower than those observed in the elevated CO2 or ozone treatments alone.

What it means
Soybeans should continue to display increased rates of photosynthesis as the concentration of atmospheric CO2 continues to rise.  Furthermore, elevated CO2 will likely reduce stomatal apertures in this species, thereby causing less indiscriminate uptake of harmful aerial pollutants, including ozone.  This consequence of atmospheric CO2 enrichment should alleviate some of the damaging effects that are caused by air pollution.

Reviewed 15 May 1999