Essay about Coral Reefs

Corals are tiny immobile animals that live in colonies, where each cluster is called a polyp. Different species build structures of various sizes and shapes, such as brain or fan coral, creating a diverse and complex ecosystem (EPA 2000). Nearly all reef-dwelling corals have a symbiotic (mutually beneficial) relationship with the algae, which live inside the coral polyps and perform photosynthesis, a process that produces food that is shared with the coral (Fagoonee 1999). In addition, the algae share its

In this episode of the BBC Documentary series, “The Blue Planet: Coral Sea” examines the roles and effects of coral reefs on other marine species. Coral reefs play a major part in the marine food web since they are responsible for about one quarter of all ocean species. Coral reefs are one of the most diversified species in the marine, even though they only covered a tiny portion of the earth. This species can reproduce both asexual and sexual. In sexual reproduction, larva is developed through egg and sperm fertilization. On the other hand in asexual reproduction, they can clone themselves through budding or fragmentation. Coral reefs, however, has been threatening due to overfishing, pollution, climate change, increasing in ocean acidity

Global temperatures are steadily rising due to anthropogenic causes; this increase in temperature is causing changes to ocean properties that can impact the organisms that call this medium their home. One of the most evident impacts of climate change on the world’s oceans is the resulting raise in ocean surface temperatures. Rising ocean temperatures can directly affect biogenic reef building organisms like corals which produce some of the most diverse and productive ecosystems in the world. Previous studies within this field have determined that climate change is a notable stressor for these corals causing large scale bleaching events; where they release their photosynthetic symbionts. Once the symbionts of these organisms are released corals begin to starve and ultimately die resulting in

Coral reefs exist all over the world and are generally known as being one of the most diverse, intricate and beautiful of all existing marine habitats. They have many varying structures which are developed by algae and are symbiotic with various reef building corals which are referred to as, zooxanthellae (algae). There are many other factors such as, coralline algae, sponges and other various organisms that are combined with a number of cementation processes which also contribute to reef growth, (CORAL REEFS, 2015).

Coral bleaching is normally characterized by the expulsion of the zooxanthellae algae, loss of algal pigmentation, or both. Coral bleaching events have had serious effects on corals and reefs worldwide. What is crucial to the understanding of zooxanthellae expulsion and bleaching is how the density of zooxanthellae within the coral is changing, if at all, under the prevailing range of environmental conditions (Gates and Edmunds, 1999). Over the last twenty years, there has been a dramatic increase in both the frequency and intensity of coral bleaching events. Sixty major bleaching events have been reported between 1960 and 1979, whereas only nine were reported prior to 1979 (Huppert and Stone, 1998). Given the dependence of the coral on this symbiotic algae, it is important to determine the cause of these bleaching events. According to Helvarg (2000, p.12):

Since early 1998, climate change has been demonstrating its effects in increasing the ocean 's temperature (West & Salm, 2003). Warm water stress corals causing the phenomenon known as coral bleaching, by which expulsion of colourful symbiotic algae the zooxanthellae, vital for

A third problem the coral reefs face is strangulation by seaweed. The over-fishing of the coral reefs leads to a decrease in plant-eating fish. This leads to an overgrowth of seaweed which block the light from the coral causing death to the coral reefs. (Denecke, 2001)

Coral reefs are natural formations that host around twenty-five percent of the world’s marine species, however, these reefs are majorly threatened (“Air”). The Great Barrier Reef in particular is an important marine location, home to major marine diversity with over 3,000 reefs over 1,400 miles (“Great” World Book). The Great Barrier Reef is a limestone formation made of coral polyps and algae, and lays off the coast of Queensland, Australia. For many years, this reef has been exposed to several threats. The threats facing the Great Barrier Reef include pollution, invasive species, and climate change.

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

These increasing ocean temperatures, which result in global warming, are mostly due to the amount of CO2 released in the air, therefore threatening the existence of the coral reef systems (Cole, Pratchett and Jones). The reduction of the coral reef ecosystems are attributed to the climate induced bleaching from the past decade. The loss of coral reef environments has direct affects to the habitat of an organism within the reefs (Cole, Pratchett and Jones), leading to a decrease in biodiversity (Coker, Pratchett and Munday).

The coral reef’s ecosystem are in major threat of the current bleaching events. Coral reefs are the main marine environment, which includes a variety of over 4,000 fish, and 800 different type of hard coral (“Corals”). Over 25 percent of marine animals are supported by the coral environment (“Coral Reefs”). The reefs are a key element of the ocean’s ecosystem (“Coral Reef Destruction”). Water temperatures are estimated to keep rising in the decades to come, which intensifies coral bleaching and other problems like black band disease, and white plague. These illnesses cause a majority of the coral to die, which will then lead to their ecosystem to plummet (“Global Warming”). Research as estimated that one to eight million organisms are yet unknown to scientists

According to the latest research of scientist team led by the University of New South Wales (UNSW), tropical corals cannot survive without the Symbiodinium algae that live inside them. These photosynthetic organisms supply the corals with all their food, more than 90 percent. UNSW specialists say that increased water temperatures stress the algae, provoking them to produce an excess of toxic substances, which called reactive oxygen species. As a result of intoxication, damage both the algae and the corals.

Coral reef ecosystems around the globe are threatened by human interferences and climate change. This has led to many scientists conducting studies on global coral reef ecosystems to gain a better understanding of the cause and effects of coral reef damage. In both Hodgson’s (1999) and Carpenter et al.’s (2008) studies, they are aware of the continuous degradation of global coral reef ecosystems. Hodgson's study involved conducting a survey on global coral reef ecosystems to see whether human actions were affecting the health of supposed pristine Coral reefs. Carpenter et al. incorporated Hodgson’s study into a compiled study about the possible extinction of reef building corals due to climate change and anthropogenic effects. Carpenter’s

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).