Coral reefs throughout the Caribbean are nearing a dangerous tipping point, says a new analysis published Tuesday in the journal Nature Communications, as erosion begins to outpace the plummeting growth rates of new reef structures threatening some of the planet's most biologically diverse ecosystems.
"Current rates of reef growth in the Caribbean are extremely alarming," said University of Exeter Professor Chris Perry, who led the research. "Urgent action to improve management of reef habitats and to limit global temperature increases is likely to be critical to reduce further deterioration of reef habitat."
According to the report:
Global-scale deteriorations in coral reef health have caused major shifts in species composition. One projected consequence is a lowering of reef carbonate production rates, potentially impairing reef growth, compromising ecosystem functionality and ultimately leading to net reef erosion.
Corals’ production of calcium carbonate—the bony material that creates new reefs—is down by at least half, and in some places 70 percent lower, than in the pre-industrial era meaning that many are already below the threshold where enough carbonate is produced to maintain the skeletal reef structure in the face of erosion.
According to a University of Exeter press release, because of recent ecological declines—driven by human disturbance, disease and rising sea temperatures— "many coral reefs across the Caribbean have seemingly lost their capacity to produce enough carbonate to continue growing vertically."
This inability to self-generate, warns Perry, will have major implications on the ability of these valuable marine ecosystems to respond positively in the future when faced with global warming-induced sea level rise.