Oil slicks taken from a space shuttle

Sedimentation is one the biggest threats to coral reefs today. In recent years, there have been several constructions along coast mining. In addition, farming and logging of rainforests cause soil run offs blocking the coral reef biomes from obtaining sunlight, a crucial source of energy.

In depleted fisheries, people resort to desperate tactics to catch the fish that remain– one of those is dynamite. The explosions send dead fish to the surface and destroy living coral reefs.

Water pollution is also a major cause of the endangered-ness. Petroleum products and chemicals are lethal to coral reefs. Raw sewage is also dumped in the sea causing and overload of nutrients; algae takes over the sunlight and all the plants needing sunlight die.

Reefs also are threatened by tidal emersions. Long periods of exceptionally low tides leave shallow water coral heads exposed, damaging reefs. The amount of damage depends on the time of day and the weather conditions.

Link:

http://www.solcomhouse.com/coralreef.htm

In the sea, simple plants, known as algae, are the most important organisms at the bottom of the food chain. More complex algal plants include seaweeds, which are an important diet for many fish. There are several kinds of algae including, coralline algae are a type of red algae that lay down skeletons of calcium carbonate and work with corals in building reefs and cementing the rubble together.

In addition to algae plants there are also mangroves, trees and shrubs that grow in the intertial zone between the land and the sea. The only plants that are actually submerged in the water are seagrasses.

Both seagrasses and mangroves are abundant and diverse in tropical waters. These plants are vital because they filter and hold the sediments in the water and thus keep the water in the coral reef clean and clear.

Link:

http://encarta.msn.com/encyclopedia_761572186_2/Coral_Reef.html

http://www.nbii.gov/portal/server.pt/gateway/PTARGS_0_2_2123_203_209_43/http%3B/PUBLIC-CONTENT%3B7087/publishedcontent/publish/habitats/coral_reefs/what_is_coral_intro/intro_content_2.jpg

This is a sponge in the Great Barrier Coral Reef of Queensland, Australia

Coral reefs are home to a variety of tropical or reef fishes, such as the colorful parrotfishes, angelfishes, damselfishes and butterflyfishes. Other fish groups found on coral reefs include groupers, snappers, grunts and wrasses. Over 4,000 species of fishes inhabit coral reefs.

Reefs are also home to a large variety of other organisms, including sponges, Cnidarians (which includes some types of corals and jellyfish), worms, crustaceans (including shrimp, spiny lobsters and crabs), molluscs (including cephalopods), echinoderms (including starfish, sea urchins and sea cucumbers), sea squirts, sea turtles and sea snakes. Aside from humans, mammals are rare on coral reefs, with visiting cetaceans such as dolphins being the main group. A few of these varied species feed directly on corals, while others graze on algae on the reef and participate in complex food webs.

These are just the many few species that habitat and survive in this ecosystem.

Link:

http://www.enchantedlearning.com/biomes/coralreef/coralreef.shtml

http://www.answers.com/main/Record2?a=NR&url=http%3A%2F%2Fcommons.wikimedia.org%2Fwiki%2FImage%3ACoral%2520reef%2520locations.jpg

The red areas show the areas where the coral reef communities habitat

Coral reefs are estimated to cover 284,300 square kilometers, with the Indo-Pacific region (including the Red Sea, Indian Ocean, Southeast Asia and the Pacific) accounting for 91.9% of the total. Southeast Asia accounts for 32.3% of that figure, while the Pacific including Australia accounts for 40.8%. Atlantic and Caribbean coral reefs only account for 7.6% of the world total. Coral reefs are either restricted or absent from along the west coast of the Americas, as well as the west coast of Africa. This is due primarily to upwelling and strong cold coastal currents that reduce water temperatures in these areas. In addition, corals are restricted from off the coastline of South Asia from Pakistan to Bangladesh. They are also restricted along the coast around north-eastern South America and Bangladesh due to the release of vast quantities of freshwater from the Amazon and Ganges Rivers respectively.

The reason why the coral reefs do not grow out in the ocean is because the coral reefs require a specifics kind of environments to habitat it, specifically shallow waters. The waters in Southeast Asia are much more shallow, as a result, coral reefs grow more in this area.

Some famous coral reefs include:

1. The Great Barrier Reef – the world’s largest coral reef system in the world. It is in Queensland, Australia.

2. The Belize Barrier Reef – the world’s second largest coral reef system in the world. It is in Belize, Central America.

3. The Pulley Ridge – the deepest photosynthetic reef in the world. It is located in Florida.

http://earthobservatory.nasa.gov/Study/Paleoclimatology_CloseUp/Images/coral_reef.jpg”>

Coral Reefs are the most diverse marine communities on earth

Coral reef communities are second only to rain forest in diversity. They are the most diverse marine community, supporting more species and numbers of organism than any other aquatic zone. Coral reefs are extremely sensitive to pollution. Tropical marine waters with little to no nutrients in the water are the best suitable environments for the coral reefs to grow in. High nutrient levels such as that found in runoff from agricultural areas can harm the reef by encouraging the growth of algae. Many reefs around the world are threatened, and many have been damaged or destroyed as a result of human activities. Coral reefs are formed in the neuritic zone of tropical areas. Like tropical rain forests, coral reefs are very productive and rich in species. The neuritic zone in which this aquatic biome resides in is the most productive zone in the ocean. One vital reason is due to the shallowness of the water through most of the neuritic zone. It is shallow enough for photosynthesis to occur. Strong currents called upwelling carry nutrients from the ocean bottom and mix them with nutrients contained in runoff from land. These waters are rich in plankton, communities of small organisms that drift with the ocean currents. Planktons are consumed by many larger animals.

The process of nutrient cycling between corals, zooxanthellae, and other reef organisms provides an explanation for why coral reefs flourish in these waters: recycling ensures that fewer nutrients are needed overall to support the community.

Some of the organism’s in the coral reef including, cyanobacteria provide soluble nitrate for other organisms through nitrogen fixation. Corals absorbs nutrients, including inorganic nitrogen and phosphorus, directly from the the water.

Link:

http://www.answers.com/Coral+Reef?cat=technology