MEPS prepress abstract - doi: 10.3354/meps07398
Coral calcification from skeletal records revisited
Janice M Lough
ABSTRACT: Skeletal growth records in annually-banded massive coral skeletons are an under-exploited archive of coral responses to environmental changes. Average linear extension and calcification rates in Indo-Pacific Porites are linearly related to average water temperatures through 23o-30oC. Assessing long-term trends in Porites extension and density requires caution as there is evidence of an age effect whereby in earlier growth years corals will tend to extend less and form higher density skeleton that in later years. This does not appear to affect calcification rates. Coral growth characteristics at two of three reefs in the central GBR provide evidence of a recent decline. This is of concern although the exact causes cannot be identified. International efforts are required to make full use of both coral growth histories and geochemical tracers contained in massive coral skeletons to understand the nature and significance of recent trends and their possible links with environmental changes such as ocean chemistry, warming tropical oceans and increased frequency of coral bleaching events.