Coral reefs are large underwater structures composed of the skeletons of colonial marine invertebrates called coral. Each individual coral is referred to as a polyp. Coral polyps live on the calcium carbonate exoskeletons of their ancestors, adding their own exoskeleton to the existing coral structure.

Reefs form when corals grow in shallow water close to the shore of continents or smaller islands. As the corals grow and expand, reefs take on one of three major characteristic structures —fringing, barrier or atoll. 

• Fringing reefs are the most commonly seen reef and grow near coastlines.
• Barrier reefs differ from fringing reefs in that they are separated from the coastlines by deeper, wider lagoons. 
• The rings of coral that makeup atolls create protected lagoons in the middle of the oceans, typically around islands that have sunk back down into the ocean.

The largest of these coral reef systems is the Great Barrier Reef in Australia. It plays an important role in maintaining the coastal ecology of the world in the following manner.

• It provides food, shelter and breeding area to at least 400 individual species of coral.
• It is the primary habitat for more than thousands of different species of fish, mollusks, sea snakes, sea turtles, whales, dolphins, birds and more. Their destruction can lead to the extinction of thousands of species of marine life. 
• They reduce the damage in case of storms, hurricanes and tsunamis by absorbing wave energy and contribute to environmental protection through the reduction of coastal erosion.
• They protect ecosystems located between the reefs and coasts, such as seagrass and lagoon for example, and human settlements located by the sea.
• Reefs also protect the highly productive wetlands along the coast.

FAQs related with Types Of Formations Of Coral Reef

Ques 1. What are the different types of coral reef formations?

Ans. Coral reefs can be categorized into three main types: fringing reefs, barrier reefs, and atolls. Fringing reefs grow directly from the coastline, bordering the shore. Barrier reefs are separated from the mainland by a lagoon and run parallel to the coastline. Atolls are circular or horseshoe-shaped reefs that encircle a central lagoon and are typically found in open ocean settings.

Ques 2. How do fringing reefs differ from barrier reefs and atolls?

Ans. Fringing reefs are the most common type and develop close to the shore, growing directly from the coastline. Barrier reefs are situated farther offshore, with a lagoon separating them from the mainland. Atolls are formed from the subsidence of volcanic islands, leaving behind a circular or horseshoe-shaped reef structure surrounding a central lagoon.

Ques 3. What factors influence the formation of different reef types?

Ans. The formation of different reef types is influenced by various factors, including sea level changes, geological activity, and ocean currents. Fringing reefs often form in areas with stable coastlines and shallow water depths. Barrier reefs can develop when there is subsidence or when sea levels rise, creating a deeper lagoon. Atolls form when volcanic islands sink and erode over time, leaving behind a ring-shaped reef structure.

Read Also : How Coral Reefs Are Made?