As carbon dioxide (CO₂) emissions to the atmosphere continue to skyrocket, so does the amount of CO₂entering the world’s oceans. With this increase in CO₂, the oceans are becoming more acidic, causing a host of problems and stressors for organisms living within the oceans. One of these issues is that some marine organisms that create calcium carbonate shells or skeletons, such as clams, mussels, lobsters and corals, have a harder time building their shells in a more acidic environment.

Associate Professor Dr. Justin Ries is an expert in carbonate biogeochemistry and evolutionary biology. In his most recent collaborative publication, Ries and colleagues make a call to action for more comprehensive empirical and theoretical studies on how corals will react to ocean acidification across multiple functional scales—from the coral cell to the reef ecosystem. In the study, published in the journal BioScience, Ries and co-authors explain that the majority of research concerning ocean acidification is restricted to the responses of individual organisms within a given species.

The challenge going forward, the study notes, will be to quantify coral responses at the level of the cell, organism, population, and ecosystem. The study also notes the importance of understanding how these various responses interact with one another, both to improve our fundamental understanding of the impacts of ocean acidification but also to improve multi-scale models used to predict the impacts of ocean acidification on reef systems for the purposes of conservation, habitat replenishment, tourism, and fisheries management.

As a testament to the importance of study, the cover of the corresponding issue of BioScience (at right) features the first high-resolution electron image of a coral showing the spatial relationship of the various components involved in coral reef construction, including the skeletal crystals, calcifying fluid, tissue, and symbiotic bacteria and algae of the coral. This novel image was obtained by Ries on the state-of-the-art scanning electron microscope recently acquired by the Marine Science Center at Northeastern.

As mass bleaching events due to rising sea surface temperatures continue to make worldwide news, Ries and colleagues highlight that comprehensive studies are needed now more than ever to also understand the threats—from cell to ecosystem—that ocean acidification poses for the world’s coral reefs.