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Adding rocks to oceans could de-acidify water and save coral

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    Scientists are currently looking for ways to slow down ocean acidification. One of the means discovered would be spreading an ore, olivine, on the coasts. The oceans of our blue planet have become 25% more acidic since the industrial revolution. A consequence of the excess of CO2 in the air which then forms carbonic acid (HCOOH) by dissolution. Unfortunately, this acidification is a great threat to the marine ecosystem (such as corals, mussels, sea urchins, etc…). The elaboration of shells and skeletons is much more difficult because of this strong acidification.
    To remedy this acidification, Francesc Montserrat, sea researcher at the Royal Netherlands Institute, studies olivine. This stone natively eliminates acidity in water by exchanging its magnesium ions (Mg2+) for H+ ions, a factor of acidity when placed in seawater. According to studies, this solution was already considered for the atmosphere, large quantities would be needed to have a global effect. When olivine is applied in small doses: the pH increases.
    This has no harmful effect on life, however at higher amounts it becomes harmful to life by releasing nickel and induces a drastic increase in pH. This process needs to be finalised and legal issues need to be resolved since materials cannot be dumped into the sea. “And one of the key issues to be addressed is whether the effects of olivine could be reversed if it started to harm the environment”.

  Aram Dulyan (User:Aramgutang), Public domain, via Wikimedia Commons