Effects of seawater pCO2 on the skeletal morphology of massive Porites spp. corals
Abstract
Ocean acidification alters the dissolved inorganic carbon chemistry of seawater and can reduce the calcification rates of tropical corals. Here we explore the effect of altering seawater pCO2 on the skeletal morphology of 4 genotypes of massive Porites spp which display widely different calcification rates. Increasing seawater pCO2 causes significant changes in in the skeletal morphology of all Porites spp. studied regardless of whether or not calcification was significantly affected by seawater pCO2. Both the median calyx size and the proportion of skeletal surface occupied by the calices decreased significantly at 750 µatm compared to 400 µatm indicating that polyp size shrinks in this genus in response to ocean acidification. The coenosteum, connecting calices, expands to occupy a larger proportion of the coral surface to compensate for this decrease in calyx area. At high seawater pCO2 the spines deposited at the skeletal surface became more numerous and the trabeculae (vertical skeletal pillars) became significantly thinner in 2 of the 4 genotypes. The effect of high seawater pCO2 is most pronounced in the fastest growing coral and the regular placement of trabeculae and synapticulae is disturbed in this genotype resulting in a skeleton that is more randomly organised. The study demonstrates that ocean acidification decreases the polyp size and fundamentally alters the architecture of the skeleton in this major reef building species in the Indo-Pacific Ocean.
Citation
Allison , N , Ross , P , Brasier , A , Cieminska , N , Lopez Martin , N , Cole , C , Hintz , C , Hintz , K & Finch , A A 2022 , ' Effects of seawater pCO 2 on the skeletal morphology of massive Porites spp. corals ' , Marine Biology , vol. 169 , 73 . https://doi.org/10.1007/s00227-022-04060-9
Publication
Marine Biology
Status
Peer reviewed
ISSN
0025-3162Type
Journal article
Rights
Copyright © The Author(s) 2022. Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visithttp://creativecommons.org/licenses/by/4.0/.
Description
This work was supported by the UK Natural Environment Research Council (award NE/I022973/1) to AAF and NA.Collections
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