We are not often aware of it, but the coral certainly has a major impact on humans. The reef provides food, medicines, it is suitable as a building material and they are also natural breakwaters.
Medicines
Corals can be used as medicine, this has been done by indigenous peoples for years. In the Philippines, for example, they eat the flesh of font clams that helps against malaria and the ancient Hawaiians used black coral mixed with other ingredients to combat lung diseases.
Animals that live close together, such as coral on a reef, often produce poison to repel their competitors and defend themselves against large fish. For example, fire corals, stonefish and crowns of thorns are poisonous to humans. It was not long ago that man realized that it might be a potential application for modern medicine, as many reef organisms have been discovered to possess pharmacological and microbiological properties.
At the moment there is a lot of research on the healing properties of the corals, but coral skeletons have been used for a while. The skeletons of reef-building corals are very similar to the structure of human bones. French researchers have discovered that these coral skeletons can be used in bone grafts. It is placed in the body in broken or cancerous bones, or it is used to lengthen bones. Blood penetrates into the small channels of the coral skeleton, which slowly dissolves. It is then, usually within 3 weeks, replaced by new bone. The coral skeleton has a great advantage. Unlike many other materials, the coral skeleton is not rejected by the body because it is not perceived as foreign material by the immune system.
Reefs as natural breakwaters
Reefs act as natural breakwaters between the ocean and land. They provide the necessary protection for the habitats behind them and the people who live there. Coral extraction causes the reefs to be lost and destroyed or weakened as natural breakwaters protecting the coast from erosion. Removal of coral also means the removal of the material that eventually breaks down into sand for the beaches, which also play a role in protecting the coast. Removing coral debris and beach sand and dredging sand from lagoons and seagrass beds further reduces protection against waves and storms and increases erosion rates.
Asia is increasingly affected by monsoon winds and monsoon rains between May and October. Floods are increasing, displacing villagers and leaving thousands homeless. Much of this is due to poorly planned coastal development, poor piers, but also partly to the extraction of coral and sand. The growing fear of sea level rise and the increase in storms due to global warming has made erosion a major issue. Many of the low-lying countries are relatively poor and cannot afford the construction of artificial breakwaters to replace damaged reefs.
Under certain circumstances, coral extraction can be beneficial to marine life, provided it is done carefully and on a small scale. In the Pacific, atolls are often surrounded by a wide reef shelf, where dead coral and lime seaweed are extracted. Choosing suitable sites on such a reef and leaving holes 2 to 4 meters deep after the coral has been extracted will attract shelter-seeking reef animals, creating thriving reef communities over time.
The harvest of coral
Both businesses and local residents can make good use of the paved part of the coral reef as a building material. It is also often taken from the oceans, because it looks great in an aquarium or in a collection. In the past, you could buy necklaces in stores that consisted of polished pieces of coral, as well as other products made of coral. This is now punishable almost everywhere in the world and therefore you do not see it often. However, it is still sold on the illegal circuit.
There is also a lot of fishing on the reefs. Millions of kilos of fish are extracted from the oceans every year, generating a lot of money for the lands around the reefs.
Tourism
A large part of the countries with large coral reefs depend on tourism. The coral reefs attract divers who book special diving holidays for this. The disappearance of the reefs could therefore have major consequences for affected countries and for that reason alone they should do their best to conserve the reef. However, it is not only good that there is so much tourism. Divers who are not properly trained will destroy the coral and that poses a serious threat. A coral polyp cannot withstand a human fin strike and will break down or die. In most places in the world you can see that the fan corals on the ground have dived because they have been kicked to pieces by divers.
In the coming years, tourists will often go diving or snorkeling on the reefs and therefore more and more care is taken to preserve the reef.