Does elevated pCO2 affect reef octocorals?
Article first published online: 26 NOV 2012
© 2012 The Authors. Ecology and Evolution published by Blackwell Publishing Ltd.
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Ecology and Evolution
Volume 3, Issue 3, pages 465–473, March 2013
How to Cite
Ecology and Evolution 2013; 3(3): 465–473
- Issue published online: 11 MAR 2013
- Article first published online: 26 NOV 2012
- Manuscript Accepted: 22 JUL 2012
- Manuscript Revised: 14 JUL 2012
- Manuscript Received: 13 JUN 2012
- Israel Cohen Chair in Environmental Zoology
- Israel Science Foundation
- Climate change;
- ocean acidification;
- Red Sea
Increasing anthropogenic pCO2 alters seawater chemistry, with potentially severe consequences for coral reef growth and health. Octocorals are the second most important faunistic component in many reefs, often occupying 50% or more of the available substrate. Three species of octocorals from two families were studied in Eilat (Gulf of Aqaba), comprising the zooxanthellate Ovabunda macrospiculata and Heteroxenia fuscescens (family Xeniidae), and Sarcophyton sp. (family Alcyoniidae). They were maintained under normal (8.2) and reduced (7.6 and 7.3) pH conditions for up to 5 months. Their biolological features, including protein concentration, polyp weight, density of zooxanthellae, and their chlorophyll concentration per cell, as well as polyp pulsation rate, were examined under conditions more acidic than normal, in order to test the hypothesis that rising pCO2 would affect octocorals. The results indicate no statistically significant difference between the octocorals exposed to reduced pH values compared to the control. It is therefore suggested that the octocorals' tissue may act as a protective barrier against adverse pH conditions, thus maintaining them unharmed at high levels of pCO2.