The Coral Reefs Essay

Corals build colonies that secrete calcium carbonate to form ocean reefs. When they're healthy, coral reefs provide shelter and food for animals all along the food chain, including the top: us. Across the planet, half a billion people rely, directly and indirectly, on corals for their living. That's why what happens to the 9,000-year-old Great Barrier Reef, as well as to other reefs worldwide, is critical. The floods in Queensland have hurt the Great Barrier Reef by funnelling into the ocean vast plumes of freshwater and agricultural runoff that could severely damage the coral. Besides the extreme rain that sparked the floods, rising ocean temperatures, changes to the ocean's chemistry and the global trade in natural resources — all symptoms of our fossil-fuel economy — are waging a multiform war on the marine

Coral reefs not only protect coastlines and beaches from wave damage and erosion, but also are the basis for the fishing and tourism industries. Dying reefs is a worldwide problem, and evidence shows that 10% of the entire world’s coral has died, and 60% will die by 2020 if existing conditions continue (NOAA 2000). The reason that the Australian Great Barrier Reef is so important is because not only is it the largest barrier reef in the world, but it is also one of the most evolved models of how to best manage and protect the world’s largest reef system (Ornitz 1996). It extends for 2,340 kilometers (km), covers 345,000 square km and contains 2,900 reefs, 300 coral cays and 600 continental islands (White 1999). Historically, it has been ahead of the rest of the world in terms of recognizing and addressing problems associated with reef degradation.

The Ocean is a miraculous place filled to the brim with foreign creatures and wondrous wildlife. From the Great Orcas of the Antarctic waters to the minuscule plankton, these marine life conquer the ocean's depths, but it's not just the creatures that reside here. Coral occupy their fair share of space upon the ocean's floor filling the waters with their glamour and residential charm for those in search of shelter.

"Coral reefs… are fragile structures living within a narrow range of temperature, clarity, salinity and chemistry. Even a slight increase in ocean temperature, or increased CO2… can cause stresses such as bleaching… These stresses slow the rate of growth of the corrals… With some 60 percent of the world’s coral reefs now losing productivity, it’s becoming a global crisis and a scientific mystery."

Coral reefs exist globally from 30N to 30S latitude and have existed in some form on Earth for over 200 million years. Over 2500 species of coral have been identified 1000 of which are reef building hard coral. Reefs are actually limestone structures produced by small animals called coral polyps. These polyps contain unicellular plants (algae) called zooxanthellae in their tissue. They have a symbiotic

Runoff and Pollution: Storm generated precipitation can rapidly dilute ocean water and runoff can carry pollution bleaching near-shores corals.

The rivers pollute the Reef during the tropical floods. Over 90% of this comes from farms runoff, mainly fertilisers, herbicides and pesticides. Increase of the level of acid kills the algae, which is the main food for corals. The level of pollution has been also increased by mining. Mainly Queensland Nickel.

Developing organizations, such as The Ocean Agency and the Coral Restoration Foundation, have been raising concern in efforts to conserve and furthermore sustain aquatic life and the ecosystem in which they inhabit. These unique fish, found living and populating among the coral reef, face a level of degradation and life threatening obstacles. The coral reef acts as a home to more than a quarter of the know fish species, where their population and species have been widely studied. This ecosystem is a beautiful representation of life which supports, and is supported by other neighboring ecosystems; embodying a significance as the leading consumer item for those who live along the reefs. Their importance to our planets collective ecosystem is not fully understood, due to the way these ecosystems are interconnected to one another, but nevertheless illustrates an example of a struggling life which may provide problems for both terrestrial and aquatic life-forms. Aside from the human dependency, being that “More than 450 million people live within 60 kilometers of coral reefs, with the majority directly or

The bleaching of coral reefs is when warm water forces algae to leave the reef. Once the algae disappear, the coral goes from a vibrant color to a pale white. As one marine biologist said, “You go from a vibrant, three-dimensional structure teeming with life, teeming with color, to a flat pavement...” This bleaching makes the coral more vulnerable to diseases and a greater risk of death. The biggest bleaching events to have occurred in

When thinking of oceans, people imagine the only living things that are in the waters are fish and small organisms. But there is much more some individuals may not know. Some shallow and deep oceans are home to coral. These groups of coral are classified as marine invertebrates. They breathe and consume microscopic animals called zooplankton. Coral reefs receive their energy from the sunlight, they turn it sugars for their energy. The marine invertebrates are living things that are a vital part of the ocean and human beings. Saldy these communities are in major trouble

“Coral reefs are extremely important for biodiversity, providing a home to over 25% of all marine life. They are also vital for people and business. They provide nurseries for many species of commercially important fish, protection of coastal areas from storm waves, and are a significant attraction for the tourism industry”

The key environmental points are that coral reefs provide important ecosystem goods and services for the maritime tropical and subtropical nations. Within the past two centuries, the main drivers of massive acceleration in the decrease of coral reef species that have caused widespread changes in reef ecosystems has been due to the direct and indirect effects of overfishing and pollution during agriculture and land development. Since markets for fish have gone global, along with other natural resources, reduced stocks of herbivorous fish and the nutrients from land-based activities have caused corals to be replaced with fleshy seaweed.

A coral reef is a ridge formed in shallow ocean water by accumulated calcium-containing exoskeletons of coral animals, certain red algae, and mollusks. Coral reefs are tropical, forming only where surface waters are never cooler than 20° C (68° F).

Coral reefs contain symbiotic algae called zooxanthellae which gives the coral its healthy brownish color. The algae "utilizes sunlight and the coral animal's respired CO2 to produce energy rich compounds that feed the coral host" (AIMS, 2003). When stress factors such as "heat, solar radiation, pollution, reduced salinity and changes in oxygenation" occur around the coral, bleaching can begin (Dennis). When bleaching occurs, the algae, which create nutrients for the coral to feed from, is released due to stresses to the reef. Thus the coral starves and its white calcium carbonate skeleton of the coral becomes visible (AIMS, 2003). But one of the main stresses that contributes to the lifeless white appearance of the coral is the warmer temperatures of the sea surface water.

      Coral reefs are continuously being both built up and decomposed, so different parts of a reef are in varying stages of succession (Richmond, 1993). Coral reefs are very fragile, because reef-building organisms cannot thrive if the surrounding water changes significantly. Coral reefs require very specific conditions in order to grow: a solid structure for the base; warm and consistent water temperatures (averaging between 20 and 30 degrees Celsius); stable salinity; moderate wave action; and clear water that is low in nutrients and plankton. The water on a healthy coral reef is clear because there are very few nutrients, so plankton that would cloud the water are few. In general corals grow slowly, but they are extremely efficient at living and reproducing in these conditions (American Zoologist, pg 524-536).