Over the next century surface water pH is predicted to drop by 0.3-0.5 pH units, a process termed ocean acidification (OA), as a result of increased atmospheric carbon dioxide (pCO2). Reduction in seawater pH, correlated to a decline in calcium carbonate saturation state (Ω), will likely affect rates of calcification in marine organisms. The potential negative effects of OA are likely to be greatest for ecosystems where the foundation and framework species are calcifiers. Coral reefs are therefore among the most vulnerable to changing seawater carbonate chemistry as the resident corals and coralline algae deposit calcium carbonate and build the complex habitats that support extremely high levels of biodiversity in these systems. Thus not only are the corals and other calcify- ing reef organisms likely to suffer directly from OA, but the cascading consequences of habitat loss to the flora, fauna, and human societies dependent on these systems is likely to be great. There is an urgent need to understand the effects of OA on coral reef species, communities, and landscapes in an effort to predict the biological consequences of global change on these vulnerable natural systems.
Smith J. E., & Price N., 2011. Carbonate chemistry on remote coral reefs: Natural variability and biological responses. OCB News 4(1):7-11. Article & OCB Newsletter.
