Red Sea coral reefs are in danger of bleaching if the temperature drops – study

Coral living in the Northern Red Sea and the Gulf of Aqaba are at risk of bleaching if water temperatures drop, new research has shown. A joint collaboration between Bar-Ilan University, Mina and Everard Goodman, Faculty of Life Sciences, and the Interuniversity Institute of Marine Science in Eilat and published in the journal PeerJ, tested coral at a lower temperature in controlled experiments to determine whether it would be affected. Bleaching is the process by which coral, one of the most diverse ecosystems on the planet, is affected by a change in temperature and the algae that live in their tissues so that they turn white. Previous research by Professor Maoz Fine of Bar-Ilan University and his team has shown that the coral reefs of Israel’s shores show a high tolerance for the increase in seawater temperature. compared to other reefs around the world, research that could have valuable implications for global warming and rises in sea temperature. Sea Simulator System to expose coral to higher temperatures that are expected to occur during global warming, Fine and his team originally found that the coral handles the warmer water well. However, with experts predicting that the Red Sea will enter a cooler period, the results show how much just a slight drop can cause damage to a large ecosystem.

“Although we have repeatedly shown the high temperature tolerance of coral on the shallow reefs in Eilat, we wanted to test the possibility that this extraordinary heat tolerance is accompanied by the consideration of being cold sensitive,” said dr. Jessica Bellworthy said she did her doctoral research in the Fine department.

“Indeed, we have found that exposure to cold water periods triggers a physiological response similar to bleaching.” seen in other corals under heat stress. This proved how close the coral of the Red Sea is to their lower temperature threshold. The research showed that the damaged, cooler coral did not die and in fact returned to their previous state. They were then tested again at a higher temperature to see if the cold stress had an effect. “It was an important discovery for us to understand that even the individuals who had the cold winter stress still did not bleach at the high temperatures,” Bellworthy said. Scientists have estimated that between 70 and 90% of all coral reefs will disappear by the middle of the century, mainly due to climate change and pollution, and the unique characteristics of the coral of the Gulf of Aqaba can provide important information for conserving other reefs. . the world.

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