Differential Effects of Ocean Acidification on Coral Calcification: Insights from Geochemistry.

Wednesday, 17 December 2014: 11:20 AM
Michael Holcomb1, Thomas M Decarlo2, Alex Venn3, Eric Tambutte3, Glenn A Gaetani4, Sylvie Tambutte3, Denis Allemand3 and Malcolm T McCulloch1, (1)University of Western Australia, Crawley, WA, Australia, (2)WHOI, Woods Hole, MA, United States, (3)Centre Scientifique de Monaco, Monaco, Monaco, (4)WHOI, Geology & Geophysics, Woods Hole, MA, United States
Although ocean acidification is expected to negatively impact calcifying animals due to the formation of CaCO3 becoming less favorable, experimental evidence is mixed. Corals have received considerable attention in this regard; laboratory culture experiments show there to be a wide array of calcification responses to acidification. Here we will show how relationships for the incorporation of various trace elements and boron isotopes into synthetic aragonite can be used to reconstruct carbonate chemistry at the site of calcification. In turn the chemistry at the site of calcification can be determined under different ocean acidification scenarios and differences in the chemistry at the site of calcification linked to different calcification responses to acidification. Importantly we will show that the pH of the calcifying fluid alone is insufficient to estimate calcification responses, thus a multi-proxy approach using multiple trace elements and isotopes is required to understand how the site of calcification is affected by ocean acidification.