A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. [1] Most coral reefs are built from stony corals, whose polyps cluster in groups. Coral belongs to the class Anthozoa in the animal phylum Cnidaria, which includes sea anemones and ...

2024年10月15日 · A coral reef is a term used to describe the collective structure of hard corals that help shape a coral reef ecosystem. “A coral reef is a reef whose main structure is made by living organisms, in this case corals,” said Torres-Pérez.

2018年9月24日 · Coral reefs are large underwater structures composed of the skeletons of colonial marine invertebrates called coral. The coral species that build reefs are known as hermatypic, or...

2022年9月5日 · A coral reef is a colony of hundreds of thousands of individual animals called coral polyps. These form when free-swimming coral larvae get attached to rocks or other hard surfaces underwater, mainly along the coastlines of islands and continents.

2024年12月24日 · Coral reef, ridge or hummock formed in shallow ocean areas by algae and the calcareous skeletons of coral polyps and other coelenterates. A coral reef may grow into a permanent coral island. Often called ‘rainforests of the sea,’ coral reefs are home to a spectacular variety of organisms.

2024年2月28日 · Coral reefs are among the most biologically diverse and valuable ecosystems on Earth. This web site describes the importance of coral reefs, threats to them, and ongoing efforts to protect them.

2019年2月1日 · Coral reefs are some of the most diverse ecosystems in the world. Coral polyps, the animals primarily responsible for building reefs, can take many forms: large reef building colonies, graceful flowing fans, and even small, solitary organisms.

What is a coral reef? Coral reefs are made up of colonies of hundreds to thousands of tiny individual corals, called polyps. These marine invertebrate animals have hard exoskeletons made of calcium carbonate, and are sessile, meaning permanently fixed in one place.

This tutorial is an overview of the biology of and threats to coral reefs, as well as efforts being made to conserve and protect them. It includes images, animations, and videos. Coral reefs are some of the most diverse ecosystems in the world.

Coral reefs are formed by huge colonies of corals that secrete hard calcareous (aragonite) exoskeletons that give them structural rigidity. These colonial hard corals may form elaborate finger-shaped, branching, or mound-shaped structures, and can create masses of limestone that stretch for tens or even hundreds of miles.