However, it is surprising that by 2010, the global coral coverage has roughly returned to the level before 1998. “This is good news,” Suter said. “Even if coral reefs are knocked down, they get up again.” Souter said that when “old growth” corals are wiped out, the new corals that move in are usually species that grow faster and have more weeds (like forests). The same as the trees after the fire). He said that this kind of growth is great, but these opportunistic corals are usually more susceptible to disease, heat and storms.
Since 2010, the global recession has been a trend to a large extent, with coral populations falling back to below 1998 levels. This is largely due to the two other global bleaching events that occurred in 2010 and 2015-2017, and corals did not receive adequate relief. Since 2019, the number of live corals has increased slightly by 2%, but it is too early to say whether this situation will continue. “If you are a very optimistic person, you might say that this happens even in high temperatures, so maybe we are seeing adaptation,” Suter said.
During the long, relatively stable and healthy period of coral reefs in the 1990s and early 2000s, on average, about 30% of coral reefs were live hard corals and 15% were macroalgae such as seaweed and turf. This is twice the number of corals and twice the number of algae. Since 2009, as the number of macroalgae on coral reefs has soared by 20%, this proportion has fallen to around 1.5. Although seaweed is also a prolific ecosystem, it is different from the complex structure of coral reefs, and it supports different fishes.
Encouragingly, the Coral Triangle in East Asia is a bold exception.This area has nearly one-third of the world’s coral reefs-and it has unusually more Live on hard corals and less Despite the rising water temperature, there are more macroalgae today than there were in the early 1980s.This is believed to be due to Genetic diversity Among the 600 species of corals in the area, corals can adapt to warm waters. “Maybe diversity provides some protection,” Suter said, while healthy herbivorous fish and sea urchin populations are suppressing seaweed.
The other three major global coral regions-the Pacific Ocean, which accounts for more than a quarter of the global total; Australia, 16%; and the Caribbean, 10%-today have fewer corals than when the survey began. “The Caribbean is a very tragic and desperate case,” said Voolstra, where there are only about 50 types of corals and one New disease Destroy them.
Suter added that the situation could be worse. “On average, coral reefs may be better than I thought,” he said. “The coral reef retains the ability to rebound, which is really amazing.”
Faced with harsh conditions, coral conservationists around the world are working hard to protect corals from pollution and actively restore them.one Recent studiesLed by Lisa Boström-Einarsson of James Cook University in Australia, through literature review, more than 360 coral restoration projects have been discovered in 56 countries/regions. Most people focus on transplanting some corals from lush places to struggling places, or “gardening” small corals in nurseries and planting them out.They also include innovative efforts, such as Electricity Promote the calcification of artificial coral reefs (an old but still controversial idea) and use diamond saw blades to cut tiny, fast-growing micro-fragments from slow-growing corals.