In the sea, the first step is to hammer the anchor at the bottom of the coral tree into the bottom of the sea. It is not a complicated operation to drive 80 cm long, 1.8 cm thick iron nails into the sea floor. However, it is not easy to get to the sea floor under the interference of pressure and buoyancy. It requires not only technical skill but also strong physical strength.

Huang Hui and her team have been doing this for more than ten years. As a researcher of South China Sea Marine Research Institute of Chinese Academy of Sciences and President of coral reef branch of China Pacific Society, saving and restoring corals is her work all the time.

June 8 is the 13th "World Ocean Day" and the 14th "National Marine Publicity Day", and this year's focus has been on coral and coral reefs.

In Huang Hui's view, it is necessary to pay attention to coral and coral reefs, because it is indisputable that "coral reefs are seriously declining and biological resources are exhausted".

Coral reefs are known as "tropical rainforests" and "seabed gardens" in the ocean, which are important parts of marine ecosystems. It provides a home for nearly 30 per cent of marine fish with less than two-thirds of the sea floor coverage.

Huang Hui stressed that healthy coral reef ecosystem is very important, and plays an important role in marine biological resources proliferation, marine environmental protection, marine disaster reduction, greenhouse effect reduction and support leisure tourism and related industries.

Moreover, coral has been a beautiful undersea landscape for 250 million years. But in the past two or thirty years, the bleaching and death of coral have become a global problem.

"The coverage of living reef building coral is an important indicator of the survival of reefs, just as forest coverage is said on land." Huang Hui said that China has a coral reef area of 38000 square kilometers, and the coral reef resources are widely distributed, mainly distributed along the coast of the mainland of South China, the coast of Taiwan Island and Hainan Island, and the East Sand Islands, Xisha Islands, China Sand Islands and Nansha Islands in the South China sea.

"China has a high diversity of reef reef coral species, a total of 445 reef reef making coral species, of which Nansha Islands has the highest reef reef reef reef species diversity, with 386 species." Huang said they not only constitute the ecosystem of the South China Sea, but also have important strategic significance.

But she said that in recent years, under the influence of climate change and human activities, especially the latter, the coverage of reefs in different regions of China has declined, and the coverage rate in some areas has even been lower than 10%. In terms of distribution, the offshore coverage is more obvious than that of the coastal reef coral.

In addition, the report on the status of China coral reefs (2010-2019) shows that the structure of reef forming coral community has changed in many areas in China, and many areas have changed from the community with high diversity to the community with cluster block as a single dominant group.

The report emphasizes that the main problems and threats facing China's coral reefs include climate change, human activities and coral disease enemies. Among them, the problems caused by climate change are more complex, including sea temperature anomaly, ocean acidification, sea level rise, extreme climate events, etc; Human activities are considered to be important factors for the degradation of coral reefs in the South China Sea, including overfishing, illegal fishing, eutrophication of sea water, coastal zone development, engineering construction and coastal tourism.

"There are a lot of laws on reef protection." Huang Hui admitted that the biggest problem lies in the lack of law enforcement power and strength, and the lack of staff and ships in the reserve, which can not effectively manage such a large sea area, and the insufficient enforcement of law also leads to too low crime costs.

In order to find out the ecological changes of coral reefs, Huang Hui investigated all the sea areas with reefs in China. She led the team to explore coral breeding and reef restoration techniques, which is "species of corals" on the bottom of the sea. By exploring different restoration techniques for different reef types, they have planted more than 200000 square meters of coral in the South China Sea bed.

Although the research work is busy, Huang Hui still insists on going to sea for nearly a month every year“ We should not only do a good job in the restoration and protection of coral reefs, but also pay attention to the basic research of the frontier, dig the secrets of the evolution of coral reef ecosystem under environmental pressure, and find the corresponding biological protection technology. " She said, known as "coral mom.".