Coral reef - Wikipedia
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 …
Coral reef ecosystems - National Oceanic and Atmospheric Administration
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 …
What Are Coral Reefs? - Live Science
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 …
What is a Coral Reef? - NASA
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 …
Coral reef | Description, Geochemistry, Origins, & Threats
2024年11月18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 …
Coral Reefs and Corals - Smithsonian Ocean
Both stony corals and soft corals can be found in the deep sea. Deep-sea corals do not have the same algae and do not need sunlight or warm water to survive, but they also grow very slowly. …
The Coral Reef: 10 Hours of Relaxing Oceanscapes | BBC Earth
2018年5月23日 · Sit back, relax and enjoy the colourful world of coral reefs as we take you on a journey through some of the most vibrant parts of our blue planet with this 10 hour loop.
13 Amazing Coral Reefs Facts - Ocean Info
Discover 13 surprising and unknown coral reef facts. Coral reefs are bustling, underwater cities that flourish in the oceans' warm and sunlit realms. Coral reefs are one of the most attractive …
Coral Reefs - UNEP - UN Environment Programme
Coral reefs underpin the safety, coastal protection, well-being, food and economic security of hundreds of millions of coastal people in least-developed countries, economies in transition, …
Corals: Nature's Amazing Underwater Cities - Ocean Info
Uncover the underwater world of corals and explore their role as the “cities” of the ocean. Learn about their fascinating biology and ecology. Corals are soft-bodied organisms with a strong …