| Summary: | Cold-water corals provide an important function in the formation of deep-water ecosystems and at high latitudes. It is estimated that by end of the century 70% of the currently known Lophelia pertusa bioherms will be exposed to waters under-saturated with regards to aragonite [Guinotte et al., 2006]. To assess L. pertusa’s response to ocean acidification it was cultured at pCO2 levels of 604, 778, 982 μatm. The long term incubation experiments show acclimatization in growth rates [Form and Riebesell, 2012]. To further investigate how this acclimatization occurs, we analyzed the geochemistry, morphology and skeletal structure of L. pertusa. The results were combined with Synchrotron X-ray Tomography (SXRTM) to reconstruct growth changes in 3D and Raman spectroscopy to examine for changes in the biomineralisation. In-situ Secondary Ionization Mass Spectrometry (SIMS) was used to quantify trace element (Mg, Sr) and δ11B composition (a proxy for pH). Results from δ11B shows that L. pertusa elevates the pH compared to that of the ambient seawater and exhibits similar systematic variation as seen in a previous study [Blamart et al., 2007]. Our data also shows lower values under high pCO2 than that of the control for the calyx wall. This gives new insight in the calcification process and a first indication for palaeo-pH reconstruction in L. pertusa.
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