Coral reefs seen from the sky

A biological construction that serves as both a graveyard and a nursery, coral reefs are formed from a pile of calcareous skeletons secreted by colonies of coral and symbiotic species.

There are several types of reefs, ranging in shape from flats to atolls. Located a long way from the shore, barrier reefs form a series of low, elongated islands separated from the coast by a channel of varying width and a depth of 10 to 70 metres. The three largest coral reefs in the world are the Australian Great Barrier Reef, which is visible from space, the New Caledonia Belt, and the Belize Barrier Reef. Although some species of coral live in the cold waters of temperate or deep regions, the vast majority are found in the top 20 metres of tropical waters.

The most complete coral structures feature a succession of brightly coloured elements.

There are several thousand species of coral, complex marine ecosystems that provide food, shelter and protection for many species. They are home to more than a quarter of the planet’s marine biodiversity (between one and three million species and 25% of all fish species) on only one thousandth of the ocean’s surface. Coral protects mangroves from waves by breaking the swell, while mangroves filter the water that reaches the coral. On another scale, micro-organisms play a role through a complex network of interactions with coral, algae, fish and other species that live in reefs.

However, corals are highly sensitive to variations in water temperature, salinity and acidity, and are now threatened by the consequences of human activities: pollution, siltation, global warming, overfishing, etc.

Unfortunately, a team of 160 scientists who studied the health of the planet’s ecosystems believes that warm-water coral reefs have passed a tipping point and are at risk of a domino effect of cascading, often irreversible disasters. Researchers estimate that with 1.5 °C of warming, the vast majority of coral will bleach and be doomed.

Sources: Wikipédia, Nouvel Observateur

The colours of all the creations in this series are inspired by those of the Australian Barrier Reef.