Click to watch the video
Oceans, which account for 71% of the earth's area, are closely linked to the fate of our humanity. Its species is rich in resources, millions of years, the ocean has brought abundant food, resources and energy to human beings, it has maintained the survival and development of human beings, the ocean as a position to participate in the global carbon cycle, play a vital role. The rapid development of industry in the 21st century, under the vision of the "community of ocean destiny", global warming, microplastic pollution, ocean acidification, ocean vulcanization, ocean hypoxia, marine heat waves, marine life chain faults, coral bleaching, seagrass degradation, marine flagship species are endangered... These are happening. Is the ocean, as the cradle of life, really inexhaustible? How much self-healing ability is left in today's oceans?
"Corals are difficult to survive without small fish, and then there are big fish, and as for humans, you can think of them as the biggest big fish." Some of the words in the documentary "Chasing Corals" are thought-provoking. The butterfly effect, the flapping of wings by a butterfly in the Amazon rainforest, will cause a hurricane, which seems to be a thousand miles apart, but it is layered and mutually causal. Like the relationship between man and the ocean, "if you fish with all your might, won't you get it?" And next year there will be no fish", in today's increasingly severe international marine ecological environment, nature has sounded the alarm bell for human beings...
Ocean heat waves
The "White Tower" at the bottom of the sea
Li Yuanchao, an associate researcher at the Hainan Academy of Oceanography and Fisheries Sciences, has been engaged in coral research for more than 20 years. According to him, in the past year, the heat wave phenomenon in El Niño was very serious, and the water temperature in the northwestern part of Hainan in 2020 was super high, and the water temperature at a depth of 20 meters in the waters had reached more than 30 degrees Celsius, and this water temperature lasted for nearly 3 months. The marine heat wave in the South China Sea in 2020 eventually led to regional coral reef bleaching events in the South China Sea, such as large-scale bleaching of corals in Lingao, Hainan, and partial coral bleaching in the Paracel Islands.
"That's the result of global warming, my teammates and I dived underwater, and as far as the eye could see, was the white tower on the seabed. Li Yuanchao said.
According to reports, the marine heat wave refers to the abnormally high water temperature in the sea area, the rise in the ocean temperature, and the super long duration of the marine disaster. The destruction of the marine ecosystem by marine heat waves is very direct, not only will it cause zooxanthellae to leave the coral, resulting in coral bleaching and death, but also affect the fish for a long period of time in the sea, which will eventually lead to large areas of fish fleeing or dying, and eventually lead to marine desertification.
Coral reef bleaching. Photo by Li Yuanchao
The world-famous Great Barrier Reef in Australia, where 30% of corals died of bleaching in 2016 and another 20% of bleaching in 2017, has become unusually fragile with little hope of recovery. Studies have shown that the demise of the Great Barrier Reef in 2016, which shocked the world, is closely related to the marine heat wave of the same period.
In the ocean, a quarter of the fish depend on the environment of the coral reef for their survival. The changes in water temperature and ocean currents caused by the ocean heat wave, and the changes in phytoplankton communities directly affect the tiniest organisms in the ocean, which are the most basic links in the marine food chain. According to the literature, marine biologists call the high sea temperatures in the Pacific Ocean from 2013 to 2016 "blisters"; during this period, phytoplankton declined dramatically, causing many marine species to "run out of food" and causing thousands of California sea lions to starve to death.
No corals
Land will disappear
The greenhouse effect has swept the world, the frequency of marine heat waves remains high, and coral reef communities face a new crisis globally: coral bleaching. If coral bleaching cannot be repaired, it can lead to marine desertification.
Li Yuanchao talked about the danger brought by the disappearance of corals to human society, "If all corals disappear, then the island countries in the Pacific Ocean will become very dangerous, and the land will gradually disappear." For example, fiji is an island nation, and scientists predict that fiji will disappear from the earth in less than 50 years. Fiji's demise is being linked to coral reef bleaching. "
Corals that are bleached by marine heat waves. Photo by Li Yuanchao
Coral reefs disappear and marine desertification sweeps across the oceans. Nutrient salts in the ocean are very scarce, and one of the roles of corals is to maintain the material circulation and energy flow in the ocean, coral bleaching leads to imbalances in its system, which will cause the collapse of the food web, and eventually lead to the disappearance of fish in coral reefs, which causes marine desertification.
One of the most direct functions of coral reefs, more significant, is the function of island building, building land, Li Yuanchao introduced: "Coral reefs are the source of sand from island reefs, if coral reefs disappear, it will have no way to create land and supplement the consumption of sea currents on islands and reefs, so that islands and reefs are eroded." "In the waters of the South China Sea, most of the islands and reefs are formed by corals, which are islands and reefs that grow from small polyps. Similarly, the Fiji island nation in the Pacific is now facing such an island crisis even more urgently.
It is understood that in order to protect mankind from the threat of climate warming, the United Nations initiated and formulated the Kyoto Protocol to the United Nations Framework Convention on Climate Change.
Long-spined starfish that eaten corals. Photo by Li Yuanchao
Is Hainan's coastal base point safe?
Notice that the "devil starfish" is infested
Talking about the El Niño phenomenon in 2020, the coral bleaching in some areas of Hainan Lingao and Xisha, Li Yuanchao said that there is no need to worry too much, 2020 as the last year of El Niño, has ended last year, the current bleaching of coral reefs is not completely dead, the situation is better, it will grow again.
It is understood that the point reef or sandbar in the South China Sea has a very limited source of sand and gravel, and coral reefs are the only source of their supply of sand and gravel. Corals are broken by typhoons or some other natural cause after formation and hit the beach to replenish the sand and gravel consumption of the island reef. Nowadays, the global ocean acidification, islands and reefs are in danger of being dissolved, and the supplementary sand and gravel cannot catch up with the dissolved, and eventually the islands and reefs will disappear, although this time will be very slow.
"At present, most of the coastal base points of islands and reefs in the South China Sea have not yet encountered erosion, and only a few islands and reefs are at risk." Li Yuanchao is optimistic about the current state of the coastal base point in the South China Sea.
Eruption of long-spined starfish. Photo by Li Yuanchao
But what made Li Yuanchao nervous was the outbreak of long-spined starfish. Long-spined starfish feed on corals and have a cycle of outbreaks in the oceans about once every 10 years. "Around 2005 and 2010, the long-spined starfish ate most of the corals in the Paracels. Due to the sharp decline in the number of snails and squirrels that constrain the long-spined starfish, the outbreak became uncontrollable, and finally almost ate the corals of Xisha. Li Yuanchao talked about the situation of the coral reef in Hainan, "The long-spined starfish didn't have to eat in the end, and I think it was probably starved to death in the end." "
Nowadays, there is no better way to restrain the flooding of long-spined starfish, the snail and the sulphurfish that restrict it, due to human overfishing, there are fewer and fewer in the ocean, and people dive into the long-spined starfish injection to control the number of populations is the most direct, but it is more difficult to operate.
Researchers dive to catch long-spined starfish. Photo by Li Yuanchao
Researchers dive to catch long-spined starfish. Photo courtesy of Li Yuanchao
Catch the long-spined starfish. Photo by Li Yuanchao
Well-grown coral reefs. Photo by Li Yuanchao
"One is that it burns a lot of money, which is not a small amount of money; the second is that it requires staff to dive and inject injections into the long-spined starfish one-on-one to achieve control of the number of long-spined starfish." Telling about the crazy reproduction of long-spined starfish, Li Yuanchao talked about the state of coral reefs in the South China Sea, he said that in more than 20 years of work, there have been disappointments, such as in the operation of repairing corals, the corals planted by him were all destroyed by typhoons after several years of repair, "but there are also very happy times, that is, I dived down to check the recovery status of corals, corals in those degraded areas gradually grew out, such as last year's coral bleaching incident in Lingao, and then we dive down to monitor. I saw that lingo's bleached reef was starting to come back to life again. "
New Hainan client, Nanhai Net, Nanguo Metropolis Daily reporter Miyaike /Wen
Source: South China Sea Network
Statement: This article has indicated the source of the reprint, if there is any infringement, please contact us to delete! Contact email: [email protected]