This view may be biased by a neglect of the effects of the plants themselves on the water chemistry. In the June issue of Ecology Letters, Schippers, Lürling and Scheffer of the Wageningen University show that, if this effect is included, productivity may double due to a doubling of the atmospheric carbon dioxide concentration.
In practice productivity increase will usually be less, however, under nutrient rich conditions, doubling of atmospheric carbon dioxide may result in a productivity increase up to 40% in saltwater species and up to 50% in freshwater species.
These results indicate that the carbon uptake by fresh- and saltwater systems may increase more than expected, and that nuisance algal blooms may be aggravated at elevated atmospheric carbon dioxide concentrations.
Journal
Ecology Letters