Coral reefs

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Coral reefs













Coral Reefs,

The City Under the Ocean

By
Nick Gray

Mr. Mullen
English 1102
27, February 1999




Coral Reefs:
The City Under the Ocean.

It was a hot sunny day off the Bahamas shoreline when my family and I went snorkeling for the first time. We took a boat out to the coral reef and dove down to find an underwater beauty. There were many different forms of life including colorful fish, different types of coral, white sand and lots of activity. The large schools of neon colored fish swam so close you could almost reach out and touch them. It was so beautiful I could explore the reef for hours.
The marine world is a vast ecosystem depending on many communities existing in harmony. Marine Biology can be branched off many ways. Coral reefs are one of the largest branches and play a major role in the marine ecosystem. They are necessary to many forms of marine life, consequently the reefs are in great danger due to mankind and natural destruction. There are scientists, students and other interested parties working to preserve the reefs.
The coral reef is an elevated part of the ocean floor in relatively shallow waters. Reefs are formed by rock like accumulation of calcareous exoskeletons, calcareous red algae and mollusks. They have built up layer by layer of living coral growing upward at rates of one to one-hundred centimeters per year. The reefs live in tropical regions starting about 30 north and south of the equator. (Darwin) About 200 to 450 million years ago the soft bodied invertebrates evolved making the coral reef the oldest and largest living community on earth. The inner layer of the reef is composed of non-living matter and the upper layer is composed of transparent polyps that grow on the remains of the once living polyps. The polyps are remarkable creatures that range in size from a small seed to as big as a lily pad and secrete calcium carbonate that forms tiny cup shaped homes. (Hinrichsen p. 554 - 555)
The reefs play a large ecological role by cycling nutrients from swamps and sea grass beds to open ocean fisheries. Many plants and animals living on the reef produce chemicals used in medicines and pharmaceuticals. The reefs bear many sources of animal protein such as fish, shell fish and mollusks for more than one billion people. They also help to stabilize and prevent shoreline erosion. (Hinrichsen p.555)
There are many types of coral reefs that mak...

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