SYDNEY, May 23 (Xinhua) -- Corals in high-latitude reefs have the ability to regulate their internal chemistry in order to maintain strong growth rates during winter time, new Australian research has found.
The study published on Wednesday, discovered that the calcification rates of high-latitude corals were threefold higher during winter (16 to 17 degrees Celsius) compared to summer (approximately 21 degrees Celsius).
"A number of factors are known to influence coral calcification, such as light, temperature, nutrient availability, and the carbonate chemistry of the seawater," lead author Claire Ross from the Centre of Excellence for Coral Reef Studies at The University of Western Australia told Xinhua.
"In addition to the environmental factors that can influence coral growth, calcification is also a biologically mediated process that is dictated by the corals' physiology."
Carried out over a two years period at Western Australia's Bremer Bay, 515km south-east of Perth, the study tracked growth rates using cutting edge tools that examine coral health.
"In particular, co-author Dr. DeCarlo developed a new method to understand the internal chemistry of corals by using specialised equipment that measures the characteristics of the molecules in coral," Ross said.
While researchers assumed the corals would grow much slower during winter due to the colder water and lower levels of light, they were shocked to find the opposite had occurred.
"We also found that there was more food in the water for corals during winter compared to summer, indicating that (in addition to internal chemical regulation) corals may feed more to sustain growth," Ross explained.
As coral reefs contain about one quarter of the ocean's fish, help to protect shorelines from waves and storms, and generate significant tourism revenues every year, marine scientists believe the results from the new study may be vital to understanding how to combat the continued decline of the invaluable ecosystems.
"The findings of this study will help better understand and predict the future of high-latitude coral reefs under CO2-driven climate change, with implications for the management of coral reefs," Ross said.
