Seemingly recovered albino corals are still "intrinsically" sick

Source: Science and Technology Daily

Science and Technology Daily Beijing, February 8 (Reporter Zhang Mengran) "appearance" seems to be restored to the albino coral, in fact, "inside" is still sick? The British "Nature Ecology and Evolution" magazine published a new study on marine science on the 8th, and a team of American scientists found that four years after the bleaching event, even if the coral has appeared to have recovered, physiological changes can still be detected in the coral. The results of the study may have reference significance for the conservation and management of coral reefs.

Ocean heat waves caused by climate change are becoming more frequent, posing a serious threat to the world's coral reefs. When the corals overheat, the algal symbiotics cease to exist, leaving only white coral tissue. In other words, it is warming that causes corals to excrete symbiotic algae that provide nutrients within their tissues, which causes corals to vilify.

Scientists can now be sure that coral bleaching can cause very serious damage to the health and functioning of coral reef ecosystems. Blabinism makes corals more susceptible to hunger, disease and death, and while some algae can make corals more resistant to high temperatures, some studies have shown that albino corals need water temperatures to return to normal before they can regain their algae and recover. Algal symbiotes can be replanted, and the "appearance" of corals appears to be restored from bleaching, but the long-term effects on coral health have not been fully understood.

In light of this, Michigan State University researchers Ford Drury, Robert Queenie and colleagues sampled rose corals during a severe bleaching event in Kaneough Bay, Hawaii, in 2015. They recorded which corals had bleaching and which corals had not. Four years later, they tested the metabolome of the same corals (the small molecules that these organisms produce in various physiological processes). The team found that corals that appeared to recover from bleaching continued to increase in saturated fatty acids and immune response molecules. They verified the above results by exposing corals with different histories of bleaching to experimental temperature stress in the experiment.

Corals may have multiple pathways to survive long-term heat waves, and they may also be able to resist bleaching or "seemingly" recover from bleaching, but these pathways of recovery are influenced by their symbiotic relationships on the one hand, and on the other hand, the improvement in their appearance does not really mean that they are "intrinsically" healthy.

The researchers also believe that testing the metabolome of corals may be a shortcut with a high cost-effectiveness that can be used to find heat-tolerant corals that can regenerate damaged coral reefs.

Editor-in-chief dots

In recent years, studies have sounded alarm bells, reminding humans that corals may become extinct globally within a few years. Different people may still have different views on climate warming, but it has already produced visible changes to the marine environment. Whilst ignified corals are more fragile corals, and if they cannot return to a suitable environment, death is their end. If taken properly, albino corals can recover, but researchers have found that even if the appearance is restored, bleaching is like a serious disease, bringing lasting sequelae to the corals. What do these after-effects mean, do they affect coral survival, and do they make them more sensitive to changes in the environment? These need further research.