Corals do not do the good of the environment only when they are alive, but continue to offer ecosystem services even after death: they are the conclusions of a study by Sorbonne and the University of Bern that have been presented at the annual general assembly of the European Geosciences Union. The research, conducted using a computer model that simulates the life (and death) of a coral reef, suggests that even the corpses of the corals play a role in the fight against global warming – although obviously it would be better to avoid reaching that extreme!
The death of the reefs. The colonies of corals have a skeleton made of calcium carbonate, which as the name suggests an important amount of CO2 In solid form and prevents her from spreading in the atmosphere: that’s why one of the negative consequences of bleaching and the death of coral reefs is an increase in greenhouse gases in the atmosphere.
It would therefore be thought that the death of a coral is a only negative event, given that all the carbon that had been retained so far in the water and in the air. And when there is more CO2 in the atmosphere, the seas also suffer from it, because this gas unites the water and then reduces the concentration of carbonate ions, which serve to build their skeleton.
Positive balance. In reality, the study shows that when corals die they set in motion a mechanism that improves the ability of the oceans to absorb co2. The calcium carbonate that comes from their skeletons and is dissolved in the water, in fact, contributes to de-acidifying the water: the study says that the reduction of acidity is equal to double the co2 which is released into the atmosphere when a coral dies.
The death of corals, therefore, increases the amount of greenhouse gases in the atmosphere; But it also serves to balance the PH of the oceans, improving their ability to retain those same gases: according to the study, thanks to the dead corals, the oceans will absorb, by the end of the century, 400 million tons of more carbon dioxide. This obviously does not mean that we must let the corals die, on the contrary; Except that their role in the fight against climate change is more complex than we thought, even after their death.
