How can ocean acidification affect corals, mollusks, and marine food chains?

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Ocean acidification, caused by the absorption of atmospheric carbon dioxide into the oceans, significantly threatens marine ecosystems by reducing the availability of carbonate ions and aragonite.1

Impact on Corals and Mollusks

Corals, shellfish, and other marine calcifiers rely on these minerals to build and maintain their skeletons and shells. As acidity increases, these organisms struggle to obtain the necessary raw materials, leading to reduced growth and weaker structures. For example, pteropod shells can dissolve in high-acid environments, and oyster larvae face increased stress and disease vulnerability. If acidification intensifies, critical coral reefs may decline or disappear, destroying essential habitats for countless species.1

Impact on Marine Food Chains

The physiological stress caused by acidification threatens the stability of marine food chains in several ways:
* Predator-Prey Dynamics: Smaller, weakened larvae are more susceptible to predation. Furthermore, as populations of key species like pteropods decline, predators must switch to new food sources, potentially causing population collapses across the ecosystem.1
* Physiological Stress: Larger animals, such as squid and fishes, may suffer from acidosis, which impairs their growth, reproduction, and respiration.1