Today (8 June) is the 14th World Oceans Day and the 15th National Ocean Awareness Day, and this year's theme is "Protecting Marine Ecosystems and Living in Harmony Between Man and Nature".
Coral reefs, as sanctuaries for marine life, are not only extremely important to marine ecosystems, but also provide us with abundant products and great economic value. Are corals plants or animals? How did they thrive? Will all corals become coral reefs? Let's get closer to corals and coral reefs through the following small science and learn about their stories↓
Existed for almost 500 million years! The coral stuff
Don't look at the coral that looks like a forest, hard like stone, and has a variety of appearances, but it is a real animal, and it is the same brother as another marine jellyfish. It is one of the oldest marine organisms on Earth, with a history of nearly half a billion years.
Corals live in tropical and subtropical waters, formed by the aggregation of polyps, a few millimeters long, with many tentacles to perform photosynthesis and prey on small plankton.
Where do the brilliant colors of corals come from? The polyps themselves are almost transparent, and in general, the color of the corals is what the symbiotic algae of the polyps is, and what color the corals show.
When subjected to some environmental stress, the chromatins and fluorescent proteins in the coral will be expressed as red, blue, purple, pink and even a variety of colors with fluorescent effects to protect the coral, and the most precious red coral is a first-class protected animal of the same level as the giant panda.
How do corals pass on from generation to generation? Most polyps are hermaphrodites, and with or without male and female, polyps can expand their populations through sexual and asexual reproduction.
Sexual reproduction can develop new territories, and fertilized eggs, although they can travel far with the sea, have a fertilization rate of less than one in a million. Asexual reproduction is the main way coral populations grow, and corals form interconnected groups, ensuring that coral populations continue to expand.
Corals are protected by law on the mainland, and it is illegal to poach, buy, sell and damage without permission, so let us protect corals together, love the environment, and build a better marine world.
Coral reefs, the treasures of the sea
What is a coral reef ecosystem? It is an ecosystem of reef-building coral remains, reef-building animal skeletons, coral reef biomes and its surroundings.
Will all corals become coral reefs? The answer is no. Polyps are divided into two categories, "reef-building" and "non-reef-building" according to whether they can form hard reefs.
Reef-building coral polyps, can absorb calcium elements and carbonate ions from seawater, synthesize calcium carbonate to form "bones", after the death of the coral "bones" will become reefs, become the foundation of new corals, repeating, repeating, accumulating tens of thousands of years into submarine coral reefs. Reef-building stony corals are the main force of reef-building corals, and there are more than 400 kinds of reef-building stony corals on the mainland, accounting for about half of the total species.
How important are coral reefs? It is a "rainforest in the ocean" that not only protects the coastline, but also maintains the biodiversity of the seabed. Typhoon waves can destroy coral reefs, but they are constantly healing themselves, largely mitigating storm surges and tsunamis from erosion of the coast.
The beautiful coral reef also provides us with a wealth of products, the current discovery of more than 600 kinds of coral reef fish, inhabiting more than tens of thousands of species of organisms, it is not only a source of food, even many new drugs are extracted from it.
Coral reefs are home to a quarter of marine life and provide food and economic resources for nearly a billion people around the world, so it can be said that coral reefs are vital to the global environment and human society.
Restoring coral reefs We are in action
The global coral reef continues to decline, and coral reef protection is imminent, how is this caused? When the ocean heats up, the coral loses its energy source, zooxanthellae, which will appear white, and once the coral is bleached, it means that it is always facing death. In addition, ocean acidification, ocean eutrophication, marine pollution, human activities, and predators of coral diseases also threaten the survival of coral reefs.
Coral reef ecosystem restoration is the most important means, through coral farming to restore the number and vitality of reef-making stony corals, but also to restore the overall coral reef ecosystem, such as cultivating organisms that are beneficial to the survival of corals, and trying to improve the surrounding environment.
In recent years, the protection and restoration of coral reefs on the mainland has made great progress, through the establishment of protected areas, public participation, publicity, etc., so that the whole society has enhanced the awareness of marine protection, scientific researchers according to local conditions, for different coral reef environments to explore different restoration techniques, the establishment of coral germplasm resource banks, effective protection of endangered coral species, more ecological restoration of a good species reserve.
It will take 10 to 20 years for a coral reef to be restored, provided that the stressors causing degradation have been lifted and that problems such as global warming are difficult to address.
I hope that everyone advocates a low-carbon green lifestyle
Put into practice the concept of environmental protection
Resist illegal coral products
Protect the oceans and coral reefs
Please start with your and my small actions
(Reporters Zhang Qin, Li Juan, ShuLin, Yu Di, Zhang Bo, Li Hui, Wang Xingli, Li Yiwen, Li Yuanzhe)
Source: CCTV News