The increase in carbon dioxide (CO₂) emissions is driving Ocean Acidification (OA). The Intergovernmental Panel on Climate Change (IPCC) predicts that, without additional restrictions on CO₂ emissions, ocean pH will continue to decline, causing severe impacts on marine ecosystems due to changes in the carbonate chemistry of seawater. This project aims to investigate the effects of OA on gastropods, focusing on the impacts on their larval shells, which are formed by less stable and more soluble calcium carbonate polymorphs, whose loss jeopardises survival.
Researchers associated with this project have observed that specific levels of pH and carbonate saturation (Ω) induce the loss of shells in gastropod larvae during early life stages, resulting in critical larval mortality. This phenomenon, distinct from previously described processes such as dissolution or abnormal secretion of biogenic carbonates by marine calcifiers under OA, occurs through the physical separation of the shell from the larval body, leaving the larvae unprotected in the water column. If confirmed, this process poses a significant threat to natural gastropod populations, disrupting life cycles and leading to population collapse under OA conditions projected by the IPCC.
Project SHELLOSS aims to investigate the biological causes of shell loss in gastropod larvae induced by OA and its relationship with pH and Ω. Experimental trials will simulate future OA scenarios, assessing the morphology, microstructure, and microchemistry of shells, alongside morpho-histological changes and sublethal effects on larval growth and development. Larval responses will also be examined across different geographical contexts and in ecologically relevant species. The outcomes of this project will clarify the mechanisms behind this phenomenon and assess its impacts on biodiversity, contributing to a deeper understanding and mitigation of OA effects on gastropods.
