coral+reefs

= = = toc Coral Reefs =

Where are coral reefs found?
Coral reefs are found around the equator. There are very few in cold depths. They cannot stand temperatures below an average of 18 degrees Celsius.

What is a coral reef?
The reefs are shallow waters made by colonial corals and their calcium-carbonate skeletons. They widely vary in growth and can over millions of years old and come many different varieties of forms. They are named for their coral animals. These animals, called [|polyps] live together and form to each other. They have hard calcium carbonate(limestone) skeletons that makeup their primary structure. The reefs build up with the help of algae that lives within the coral. The [|algae goes through photosynthesis] with the waste form the coral. The algae then gives the coral essential carbon compounds. Since the alga needs strong sunlight, coral reefs flourish within 40 meters of the surface of the ocean.

Physical Description and Formation of Reefs
Charles Darwin wrote his theory on how the structure and distribution of [|coral reefs] occurred. The build up of coral begins with a fringing reef that started around volcanoes. Over the years as corals die and thrive they build upon themselves and that turns into a barrier reef where the top of the volcano has sunken a few feet below the ocean's surface. Next, the coral reef can turn into an atoll reef with the top of the volcano sunken very far below the surface creating a lagoon in the center of the coral surrounding. Coral reefs are usually abundant in a variety of organisms when thriving. They are brightly colored and supports structure for tons of wildlife.



3 Main Types
[|Fringing reefs]- grow without a backbone structure and close to the shore line. [|Atoll reefs]- an island of coral that encircles a lagoon. [|Barrier reefs]- a coral reef separated from land or an island shore by a deep [|lagoon]

Largest Reefs:

 * 1) 1 in the world ~ Great Barrier Reefin Australia
 * 2) 2 in the world ~ Belize, Central America

About the Animals and Plants
Coral reefs have any different species and plants such as whales, dolphins and porpoises, some of the largest populations of dugongs, sea birds, turtles and snakes, fish, mollusks, corals, sea grass and sea weed and marine algae.

Zooxanthellae: Single-celled plants that live in the tissues of animals. Corals provide a protected environment for photosynthesis to zooxanthellae. Zooxanthellae provide food as products of photosynthesis.

Most species that live among the coral blend in with their habitats "camouflage." For example, clown fish live within the tendrils of sea anemones to protect themselves form predators. Other animals hide in cracks and crevices of the coral or rocks and some blend in to the sea floor. Also, some fish use the reef as a nurseries.

Video:
media type="youtube" key="4HhyHswjlJ8" height="385" width="480" align="center"

~Pictures
http://chestofbooks.com/animals/Manual-Of-Zoology/images/Fig-91-Structure-of-coral-reefs-1-Fringing-reef-2-Ba.jpg http://www.greenlaunches.com/other-stuff/scientists-plan-to-freeze-coral-reefs-for-future-generation.php http://www.coralreefinfo.com/images/coralreef_map_large.jpg http://www.reefresilience.org/Toolkit_Coral/C2a1_Zooxanthellae.html