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EPIB Trail
Volume 12, Issue 3
Ocean Acidification By Angelica Rojas
O
cean acidification has become a growing environmental problem that has led to an imbalance of species, habitats, and the overall ocean ecosystem. Ocean acidification occurs when carbon dioxide and gas emissions rise in the air due to human fossil fuel combustion. This build up of gas reduces the pH balance in the ocean and leads to wholesale shifts in seawater carbonate chemistry. Carbonate chemistry increases the concentration of bicarbonate ions (HCO) and dissolved inorganic carbon (C1) and not only lowers pH, but also the saturation of three major carbonate minerals present in shells and skeletons (Gatusso 2). This process of gas in the seawater alters the chemical speciation and biogeochemical cycles of elements and compounds. This includes lowering calcium carbonate saturation rates,
impacting shells of plankton, benthic mollusks, echinoderms, and corals. These species undergo reduced calcification and growth rates when exposed to high carbon levels (Doney 1). Ocean acidification also results in an increase in carbon fixation rates in some photosynthetic organisms. Coral reefs are one of the most biologically diverse on the planet. It is essential to human societies and providing ecosystem services (Hoegh-Guldberg 1). These include tourism, new biochemical compounds, fisheries, coastal protection, and building materials. Coral reefs have different negative reactions and responses to calcification. One response which includes a decrease linear extension rate and skeletal density coral density. There is 1.26% rate of reduction in linear extension a year; that’s a 20.6% drop in growth rate over 16 years.
