In Amendolara, we can now study the sea of the future!

Scientific interest in ocean acidification is growing rapidly, as this shift in chemical balance is occurring at an unprecedented rate, causing harmful effects on marine ecosystems.

For this reason, following the installation of the heating systems (link: urly.it/318t_7), our mesocosms have been equipped with a pH monitoring and control system: “EHEIM pHcontrol+e”.

Thanks to this equipment, it is possible to monitor and manipulate the parameters of each aquarium remotely, utilising the acidifying effect of gaseous CO₂ (better known as carbon dioxide), which is released into the tank until the value required for the study is reached. This system makes it possible to replicate in the laboratory what occurs naturally near hydrothermal vents, sites considered suitable for studies on the effects of ocean acidification due to the naturally higher acidity of their waters. Researchers can therefore use our mesocosms to complement field studies.

The ocean plays a vital role in reducing atmospheric CO₂ levels, as it absorbs a significant proportion of this gas. Whilst the ocean’s absorption of CO₂ is beneficial for the atmosphere, this is not the case for marine ecosystems. Indeed, since the Industrial Revolution, CO₂ emissions into the atmosphere have risen dramatically, causing a gradual decrease in pH with potentially negative consequences for marine life.

For example, organisms that have shells (bivalve and gastropod molluscs) or calcium carbonate structures (crustaceans, corals, plankton, sea urchins, calcareous algae) experience a reduction in their growth and development rates due to the increased acidity of the environment in which they live.

But what happens from a chemical point of view? Some of the carbon dioxide reacts with seawater to form a weak acid, carbonic acid, which in turn can dissociate into bicarbonate and carbonate ions, losing one or both hydrogen ions (H⁺); it is precisely the release of the H⁺ ions that causes the pH to drop, making the water more acidic.

Our mesocosms can now be used as tools to investigate the potential effects of an increasingly acidic sea in the near future.

We’ll update you soon on the experiments currently underway…

Stay tuned…

Text by Lorenzo Evola

Photo by Valentina Costa