Research Highlights

REU en Bermuda Institute of Ocean Science (BIOS), 2008 Melissa Meléndez Oyola, UPR-RP Programa de Ciencias Ambientales


01/14/2010

The oceans have absorbed a significant fraction of the fossil carbon released by human activities to the atmosphere. As a result, seawater pH and carbonate saturation state (?) have decreased and will continue to decrease owing to ever-increasing anthropogenic CO2 emissions. These changes in ocean chemistry could result in increased dissolution of calcium carbonate minerals, thereby affecting the formation of sediments, reefs, and other structures composed of calcium carbonate. In the present study, carbonate sediment dissolution rates were estimated under elevated CO2 conditions in Devil's Hole, Bermuda. During summer, thermally induced density stratification and microbial remineralization of organic matter in the subthermocline layer of Devil's Hole produce CO2 levels similar or higher than those CO2 levels projected by the end of the 21st century. Based on observed changes in total alkalinity (TA) and estimates of vertical flux of TA out of the subthermocline region, carbonate dissolution ranged from 0.23 to 0.93 mmol CaCO3 m-2 h-1 in the summer of 2008. On an annual basis, this corresponds to 201 to 815 g CaCO3 m-2 year-1, a significant fraction of the present day coral reef calcification rate.

Poster presentation Benthic Ecology Meeting 2009

Posted by: Loretta Roberson