Coral reefs may disappear by 2050

Corals take years to form and can be destroyed in a second. Today, reefs are threatened with mass extinction. The situation is being worsened by boating, global warming, and human actions like collecting corals or using chemicals that damage them. In this article, we'll break down whether corals have a chance to survive and how to help them.

How do corals form and why are they needed?

According to the United Nations Environment Program's Coral Reef Recovery Report, coral reefs today cover 284,300 square kilometers, an area comparable to Italy. See a detailed map of coral reefs here.

What we call coral reefs are living things that grow because of the action of colonies of coral polyps, invertebrates that have calcareous skeletons and are involved in reef formation. They release calcium carbonate from the water and distribute it beneath them in layers. This is how the outer layer or skeleton of the reef appears.

There are also soft corals. They are formed without the participation of a hard calcium base, and can be found not only in warm waters, but also in the Sea of Okhotsk and the Norwegian Sea.

Although there are very few coral reefs, they play an important role in the ocean ecosystem. Reefs produce mucus, which bacterial plankton need to eat. Corals form a nutrient medium that is actively eaten by invertebrates, which in turn are eaten by fish.

All reefs represent a quarter of marine biodiversity. They also provide food and habitat for more than 1 million species of marine animals. They also protect coastlines from the ravages of hurricanes and tsunamis. Corals reduce a wave and knock down its speed as it passes. And their impact is more serious than it may seem. The UN report contains information that in 2004, one of the largest tsunamis occurred, which affected 18 countries - 228,000 people died, but there were shores where no one was hurt, and all thanks to coral reefs.

What causes coral reefs to die?

Bleaching

The problem of coral reef extinction is global, and the destruction occurs for a variety of reasons. From 2009 to 2018, the world's oceans lost about 14% of corals. In less than 10 years, 11,700 m² of reefs worldwide have disappeared. Among the main causes is bleaching, which is caused by an increase in water temperature. If it changes dramatically from cold to hot, the symbiotic algae that live in corals change their position. As a result, the reef begins to fade and die, since algae are important to coral life and give it its famous bright color.

Microplastic

There are very small animals in the marine environment - protists - unicellular or simple multicellular, as well as phytoplankton and others. They are susceptible to the damaging effects of microplastics. This affects the development of corals because they depend on symbiotic relationships between different organisms. Microplastics can act as a stressor, affect nutrient uptake, inhibit cell detoxification activities, affect photosynthesis and increase the likelihood of cell self-destruction. This means that microplastics negatively affect the coral food chain and therefore affect the entire ecosystem.

Cyclones

Work by Australian scientists has shown that cyclones damage coral reefs even 1,000 kilometers away. Researchers studied Scott Reef, a group of atoll reefs northwest of Australia. In the most exposed areas, the reef studied lost 50% of its massive corals and almost all of its brittle branching Acropora corals. Similar damage was found on another reef 300 km away.

Oxidation

Researchers at the University of Hawaii concluded that the increasing acidity of the oceans will lead to the complete disappearance of coral habitat by 2100. Today's emissions put a great strain on marine life - when there is excess CO2, the pH level in the water drops dramatically. According to the report, in the next 20 years for 70-90% will live in conditions unsuitable for them.

Can coral reefs be saved?

Scientists are coming up with different ways to restore reef populations. For example, Charlotte Hauser and her colleagues at the Saudi University of Science and Technology have proposed 3D printing coral bases to speed up the initial stages of coral growth. These structures are closer in composition to natural coral, so that limestone polyp skeletons can form more quickly. These bases are scattered around coral growth areas to increase coral growth.

Another method was devised by researchers at the Okinawa Institute of Science and Technology: the researchers cultured coral cells for the first time to understand how they interact with their symbionts at the cellular level. The grown cultures are very sensitive to the quality of seawater, and they discolor when the temperature or acidity of the ocean rises. Scientists say their work will help better understand how corals are designed to protect them from global warming.

Some organizations and teams from around the world grow coral in their own coral plantations, which are both underwater and on land. The grown corals are then transplanted back to the reefs.

How can I help the corals?

Corals are affected by the amount of microplastics in the environment, so it is worth reducing the consumption of single-use plastics and packages made of them, as they begin to break down into tiny particles in the environment and harm both humans and marine life.

In addition, you need to pay attention to your sunscreen. Some SPFs contain a toxic compound, oxybenzone, which causes massive coral bleaching. Cream applied to the skin leaves oil-like stains on the water that reach the seafloor and damage corals.

You can also explore and support local team projects in the Humance system that focus on coral reef conservation. You can do this by clicking here.