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TROPICAL CORAL REEFS AND THE UNDERWATER
4 years ago
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Coral Reefs are the "Rainforests" of the ocean. Coral reefs are the most diverse and beautiful of all marine habitats. The magical underwater will astonish you ...


4 years ago

Coral reefs are the most diverse and beautiful of all marine habitats. Large wave resistant structures have accumulated from the slow growth of corals. The development of these structures is aided by algae that are symbiotic with reef-building corals, known as zooxanthellae. Coralline algae, sponges, and other organisms, combined with a number of cementation processes also contribute to reef growth.



4 years ago

The dominant organisms are known as framework builders, because they provide the matrix for the growing reef. Corals and coralline algae precipitate calcium carbonate, whereas the framework- building sponges may also precipitate silica. Most of these organisms are colonial, and the slow process of precipitation moves the living surface layer of the reef upward and seaward.


4 years ago

The reef is topographically complex. Much like a rain forest, it has many strata and areas of strong shade, cast by the overtowering coral colonies. Because of the complexity, thousands of species of fish and invertebrates live in association with reefs, which are by far our richest marine habitats. In Caribbean reefs, for example, several hundred species of colonial invertebrates can be found living on the undersides of platy corals. It is not unusual for a reef to have several hundred species of snails, sixty species of corals, and several hundred species of fish. Of all ocean habitats, reefs seem to have the greatest development of complex symbiotic associations.



4 years ago

Reef-building corals may occur in a variety of growth forms, and there often is strong variation in coral shape even within a species. In this photograph, we can see the branching elkhorn coral Acropora palmata (upper left), with arms showing strong orientation into an oscillatory current between left and right. In the right foreground is the mound-shaped coral Montastrea annularis. It is of great interest that such differently shaped corals can occur side by side. What might that indicate to you?



4 years ago

Acanthaster planci is a carnivorous asteroid starfish whose principal prey are corals. It has sharp dorsal spines that penetrate human skin and cause sickness. Normally it occurs at low density and is nocturnal. In the 1960s, population explosions were found all over the Indo-Pacific and the starfish were moving in large numbers during the day. Instead of being of minor impact, they were now major predators on the reef. In Guam, for example, over 90% of the corals were killed. The explanation of the origin of the outbreaks is still very controversial. Charles Birkland suggested that they were related to storms that could wash out nutrients from atolls, which stimulated phytoplankton grown, which, in turn, increased the survival of starfish planktotrophic larvae. Others have argued that larval starvation is not a limiting factor in larval survival. It was also argued that typhoons and other storms killed corals, causing starvation among the starfish and a switch to roving in aggregations in search of food.



4 years ago

Pacific shallow reefs are often dominated by the the erect coral Pocillopora damicornis. When the crown-of-thorns starfish tries to mount and consume the coral, several species of shrimps and crabs that live among the coral branches move to attack the starfish, thus defending the coral.



4 years ago

An atoll is a ring- or horseshoe-shaped group of islands, surrounding a lagoon. Coral reefs line the inner and outer parts of the island. Darwin hypothesized that the earth's crust was slowly sinking, and that corals were growing upward and keeping up with the overal sinking rate. At first, a submarine volcano might be jutting out into the sea, but sinking led to the ring of coral reefs around the volcano to grow upwards and form the islands. While most agreed with this hypothesis, the geologist Harry Ladd confirmed it by leading a drilling team to this region. The team drilled through hundreds of meters of coral reef rock before reaching volcanic rock below of Eocene age.



4 years ago

Coral Reefs are the "Rainforests" of the ocean. Reefs are ecologically important ecosystems and have a high biodiversity that serves as a storage bank of rich genetic resources. They are a source of food and medicine, and they protect the coast from wave erosion. Coral reefs are found in about 100 countries. Coral Reefs are home to over 25 percent of all marine life and are among the world's most fragile and endangered ecosystems. In the last few decades over 35 million acres of Coral Reefs have been obliterated. Reefs off of 93 countries have been damaged . When corals are stressed by high temperature, ultraviolet light or other environmental changes, they lose their symbiotic algal cells, and appear white (the white skeleton is actually visible through the transparent tissue).



4 years ago

Climate change will destroy the world's great coral reefs within a century, according to a report by German and Australian marine scientists.

The researchers say governments must take action now to reduce the emissions of gases such as carbon dioxide, which are thought to be behind a rise in average global temperatures.



4 years ago

The scientists combined their coral expertise with the latest climate models to project what is likely to happen to the world's greatest reefs if global warming remains unchecked. Their study suggests the unique marine environments will increasingly become victim to a process known as coral bleaching.


4 years ago

A slight rise in maximum water temperatures - only one to two degrees - can stress the corals. This causes them to expel the microscopic organisms, known as zooxanthellae, which color their tissues and provide them with essential nutrients.



4 years ago

If they zooxanthellae do not return, the corals will die. In 1998, the warmest year on record, every reef system in the world's tropical oceans was affected by some degree of bleaching. The report says the frequency and intensity of bleaching is set to rise.


4 years ago

The report's lead author is Professor Ove Hoegh-Guldberg, an expert on coral bleaching at Sydney University. Coral reefs could be eliminated from most areas of the world by 2100, Even the world's largest reef - the Great Barrier Reef off Australia - could be dead within 30 years unless measures are taken now to slow climate change.



4 years ago



Dolphin Reef "Coral Garden" One of the most amazing places around the world -Coral Reef-, in this case South Egypt -Red Sea-. I want to share with you the reef where I'd live if I was a fish. Dolphin Reef, light and colour, full of marine species, enjoy!



4 years ago



Amazing Coral Reefs One of the most amazing habitats on earth is found in warm, clear, shallow waters of tropical oceans worldwide. Tiny cup-shaped animals, called polyps, live in colonies, and when they die, their skeletons form a hard, stony, branching structure made of limestone.

4 years ago



under water see the under water secrets ..see the colorful coral reefs anf fishes



4 years ago

Thank you so much Dear Ee ...
Love,
Krystyna

4 years ago

Thank you very much,all these are fantastic.Wishing you all a good week.~For the Oceans~

4 years ago

Thank you Dear Mike - I'm happy you like it ...
Love,
Krystyna