Energetic Costs of Calcification Under Ocean Acidification

• Published in: Global Biogeochemical Cycles
• Main Authors: Spalding, Christopher, Finnegan, Seth, Fischer, Woodward W.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: American Geophysical Union 2017
• Subjects: Acidification; Biomineralization; Extinction; Adkins; Ocean acidification
• Online Access: https://doi.org/10.1002/2016GB005597

Anthropogenic ocean acidification threatens to negatively impact marine organisms that precipitate calcium carbonate skeletons. Past geological events, such as the Permian-Triassic Mass Extinction, together with modern experiments generally support these concerns. However, the physiological costs of producing a calcium carbonate skeleton under different acidification scenarios remain poorly understood. Here we present an idealized mathematical model to quantify whole-skeleton costs, concluding that they rise only modestly (up to ∼10%) under acidification expected for 2100. The modest magnitude of this effect reflects in part the low energetic cost of inorganic, calcium carbonate relative to the proteinaceous organic matrix component of skeletons. Our analysis does, however, point to an important kinetic constraint that depends on seawater carbonate chemistry, and we hypothesize that the impact of acidification is more likely to cause extinctions within groups where the timescale of larval development is tightly constrained. The cheapness of carbonate skeletons compared to organic materials also helps explain the widespread evolutionary convergence upon calcification within the metazoa. © 2017 American Geophysical Union. Received 10 DEC 2016; Accepted 4 MAY 2017; Accepted article online 5 MAY 2017; Published online 21 MAY 2017. This work was supported by a NASA NESSF Graduate Fellowship in Earth and Planetary Science (C.S.), the Agouron Institute, and a Packard Fellowship in Science and Engineering (W.F.). We would like to thank Christina Frieder, Adam Subhas, and Jess Adkins for helpful feedback. The data used are listed in the references, figures, and supporting information. Published - e4a2adead653f312503cdd945100d468325f37966d73504caaa72530d5a6518a.pdf Supplemental Material - 2016GB005597-T-sup-0001-Text_20SI-S01_AA.pdf Supplemental Material - 2016GB005597-T-sup-0001-Text_20SI-S01_AA.tex Supplemental Material - 2016GB005597-T-sup-0002-Figure_20SI-S01_AA.pdf Supplemental Material - ...