Impacts of ocean acidification on marine shelled molluscs

Abstract

Over the next century, elevated quantities of atmospheric CO 2 are expected to penetrate into the oceans, causing a reduction in pH (-0.3/-0.4 pH unit in the surface ocean) and in the concentration of carbonate ions (so-called ocean acidification). Of growing concern are the impacts that this will have on marine and estuarine organisms and ecosystems. Marine shelled molluscs, which colonized a large latitudinal gradient and can be found from intertidal to deep-sea habitats, are economically and ecologically important species providing essential ecosystem services including habitat structure for benthic organisms, water purification and a food source for other organisms. The effects of ocean acidification on the growth and shell production by juvenile and adult shelled molluscs are variable among species and even within the same species, precluding the drawing of a general picture. This is, however, not the case for pteropods, with all species tested so far, being negatively impacted by ocean acidification. The blood of shelled molluscs may exhibit lower pH with consequences for several physiological processes (e.g. respiration, excretion, etc.) and, in some cases, increased mortality in the long term. While fertilization may remain unaffected by elevated pCO 2 , embryonic and larval development will be highly sensitive with important reductions in size and decreased survival of larvae, increases in the number of abnormal larvae and an increase in the developmental time. There are big gaps in the current understanding of the biological consequences of an Communicated by S. Dupont.Frédéric Gazeau and Laura M. Parker have contributed equally to this work.Electronic supplementary material The online version of this article

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Free-ocean CO<sub>2</sub> enrichment (FOCE) systems: present status and future developments

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Effects of low-pH stress on shell traits of the dove snail, <i>Anachis misera</i>, inhabiting shallow-vent environments off Kueishan Islet, Taiwan

“…Although current evidence indicates that organisms with a CaCO 3 skeleton, e.g., mollusks, echinoderms, and corals, are likely to be among the most susceptible to ocean acidification (e.g., Fabry et al, 2008;Sokolov et al, 2009), specific information obtained from field investigations has been limited, particularly with regard to gastropod snails (Gazeau et al, 2013). Thus, the current study was performed to address this issue within an extreme hydrothermal environment.…”