Calcium carbonate is important for many marine animals. This chalky substance forms the ridged spicules that scaffold some sponge species, the limy deposits that build coral reefs, the protective shells of clams and snails, and the spiny-skins of sea urchins and starfish. All these organisms are important constituents of marine ecosystems, often forming the basal trophic levels that enable food-webs to function. However, there are studies that suggest increased levels of atmospheric carbon dioxide could alter the chemistry of the ocean, which could affect how marine organisms deposit calcium carbonate into their structures. This process, known as ocean acidification, could impact marine food-webs and the human communities who depend on the sea for supplementing diets and incomes.
Jonathan Booth, Policymic, 18 september 2012. Article.
