Photo: Professor Bradley Eyre sampling benthic chambers at Heron Island that have been acidified in situ to study the effect of ocean acidification on carbonate sediment dissolution.
Coral reefs to dissolve in an acid ocean by the end of the century
Coral reefs may be dissolving faster than expected under future climate change predictions, according to a new study from Southern Cross University marine scientists.
The study indicates that the increasing levels of atmospheric carbon dioxide dissolving into seawater could reduce the rate of calcium carbonate sand formation – the structural foundations of coral reefs – by up to 80 per cent by the year 2100.
The findings are contained in the paper ‘Permeable coral reef sediment dissolution driven by elevated pCO2 and pore water advection’ which was published recently in the journal Geophysical Research Letters http://onlinelibrary.wiley.com/doi/10.1002/grl.50948/abstract
The authors are PhD student Tyler Cyronak, Professor Bradley Eyre and Associate Professor Isaac Santos, all with the University’s Centre for Biogeochemistry Research (CCBR).
“Ocean acidification (OA) refers to the decrease in the oceanic pH due to increasing atmospheric CO2 dissolving into seawater, and coral reefs are thought to highly susceptible to this increasing acidity,” said Mr Cyronak.
“The formation of coral reefs is the net result of carbonate production by corals minus the loss, or dissolution of this carbonate material, which is expected to increase due to OA.”
CCBR director Professor Eyre said understanding how fast calcium carbonate sands dissolve was important to understanding how coral reefs would be affected by ocean acidification.
“Calcium carbonate sands make up the majority of the benthic habitat in coral reef ecosystems. But their dissolution is understudied as most scientists are interested in calcium carbonate production by corals.”
Yet ignoring the dissolution of carbonate sands could be a big mistake, t