Coralline algae have calcium carbonate (hard parts) in their cell walls making them vulnerable to ocean acidification. Even subtle shifts in acidity can hinder the formation of calcium carbonate and cause it to dissolve. The distribution, abundance and diversity of coralline algae will likely prove to be excellent indicators for changes in ocean chemistry due to their sensitivity to changes in pH.
Learn more about bryozoans, a marine creature that is also vulnerable to ocean acidification.