Coral Reefs Essay

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Coral reefs are systems of large, underwater structures that are composed of the mineralized bodies of corals. These corals are a class of marine invertebrates known as Anthozoans, and belong to the phylum Cnidaria, and are thus related to sea anemone and jellyfish. Each individual coral animal is only a few millimeters in diameter, and a few centimeters in length. Due to their sessile nature, and their ability to reproduce asexually, they are able to construct, over many generations, massive colonies of genetically identical individuals. Additionally, they secrete a hard exoskeleton of calcium carbonate to support and protect their bodies, and it is from this process that the colony constructs what is known as a single coral “head.” The world’s coral reefs are quintessential to global biodiversity, so much so that they are often referred to as the "rainforests of the sea". Although their actual space occupied by reefs is relatively small, constituting less than 0.1% of the world's ocean surface, they support over 25% of all marine species on earth. They provide complex and varied marine habitats that support a wide range of other organisms including, but not limited to, fish, mollusks, worms, crustaceans, echinoderms, sponges, tunicates and other cnidarians. Some of these animals feed directly on the corals, while others graze on algae on the reef. The reef also provides a protective habitat for many of these animals. In addition to their tremendous ecological benefit, coral reefs are also economically beneficial to humans, as they provide considerable services in terms of tourism, fisheries, and coastline protection. Surveys to determine their total global economic value are imperfect, imprecise, and highly varied in thei... ... middle of paper ... ...of sodium cyanide is released into a target area in order to stun fish. This method of fishing is used mainly for the capture of aquarium fish, to be sold to wealthier countries, but it is also used for catching food fish. Hundreds of thousands of pounds of cyanide are released into the Pilipino reefs each year. As you can imagine, pumping large quantities of toxins into a fragile ecosystem has negative effects. Even low concentrations of cyanide inhibits photosynthesis in zooxanthellae, a genus of algae with which coral grows symbiotically. The death of the algae removes the major food source of the coral, causing bleaching and death. The cyanide also harms the coral directly, blocking the oxygen-transporting proteins, and preventing oxygen from reaching the cells, causing death. Blast fishing is just about as ludicrous, if not more so, in practice. It is a metho

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