Food web effects of ocean acidification

Increased CO2 availability to primary producers changes the nutrient stoichiometry of these \norganisms. As a result, the quality of the primary producers as food for herbivores is affected. Here, \nwe present experimental work showing that the copepod Acartia tonsa feeding on differently grown \nRhodomonas salina is indeed affected by the CO2 availability to the algae. We discuss the potential \npathways of excreting the carbon that is in excess in high CO2 algae, and consider the possible \nconsequences of different excretory pathways for the ecosystem. \nMost likely, a continued increase in the CO2 availability for primary production, together with \nchanges in the nutrient loading of coastal ecosystems will cause strong changes in the trophic link \nbetween primary producers and herbivores, which in turn will have consequences to higher trophic \nlevels.