New Study States Marine Phytoplankton will Adjust to Rising CO2 Levels

July 6, 2015 – In some respects this is a good news story. A study appearing in the ISME Journal this month exposed 400 generations of phytoplankton to rising levels of CO2 in ocean water. At the highest levels the scientists anticipated what ocean conditions would be like by 2100. What they found is that phytoplankton populations exhibit genetic plasticity, adapting better than one would expect to an altered ocean environment.

The increasing concentration of CO2, altering the chemistry of the oceans, drove evolution in marine biota faster. The species chosen was ostreococcus (seen below), a picoplanktonic green algae, and researchers noted 16 physiologically distinct lineages evolving over 400 generations. These were categorized by cell to nuclei ratios and by overall cell size. Successful adaptation appeared better when CO2 levels fluctuated rather than when they remained stable.

The reported study is not the first that indicates algae will thrive in a changing ocean environment where more CO2 is present. In fact the adaptation of marine algae to CO2 level changes shouldn’t be too much of a surprise. Life that uses CO2 as a fuel is going to find a way.

But what this study didn’t look at is impacts of CO2 on zooplankton, far more vulnerable to increases that change the pH balance in the ocean. A more acidic ocean threatens animals that form exoskeletons and shells. That includes corals, shellfish, crustaceans and arthropods, the base of the ocean food chain.