Coral reefs rank among the most endangered marine ecosystem. They are in serious trouble from a combination of stresses that threaten their survival. These stressors include: • increasing coastal populations, which are expected to double in the next 50 years; • poor land use practices and runoff of pollutants, sediments and nutrients; • overfishing and destructive fishing practices that degrade and destroy the habitat itself; • coral bleaching, associated with increasing seawater temperatures; • acidification; and
• increase in tourist attractions.
Increased Population Growth
It is estimated that nearly 40 percent of the world’s population now lives within 100 kilometers of a coast line. Approximately 500 million depend on the coral reef in some fashion, either through fishing, costal protection, and or tourism income. Roughly 30 million people are totally dependent on the coral reef for their livelihood. (Wilkinson, C. 2008.) Because of the increase in population and how many chose to live close to the coastline, the natural landscape has been altered. Houses have been developed, hotels built for recreation, agriculture has developed. Each of these has a different effect on the coral reef ecosystem. For example, there is more sewage, fertilizers, litter that runoff into the coastal water. These poor land uses are just one reason for why the coral reef is in jeopardy. Overfishing
Overfishing is another great concern for the health of the coral reef. Over fishing causes a disruption in the ecological balance of the reef because the fish are depleted faster than they can reproduce. As mentioned previously, the zooxanthellae perform photosynthesis because of the sun’s ability to shine upon them. When overfishing occurs, the food chain for the fish is altered. The fish that eat the algae from the reef are no longer present and the reef becomes covered with algae. The algae kill the coral reef because it no longer receives sunlight and is unable to reproduce naturally. Ultimately the smallest species will not be able to survive so the food chain will be disrupted and the fish will disappear.
Destructive Fishing Practices
Destructive fishing practices go hand in hand with overfishing. There is a great market for fish world-wide so thus there is great financial gain to be made when the fish are caught. Many of these fishing sites are located in developing countries that may not have the financial resources to purchase updated equipment; instead, divers may choose to catch coral reef fish with destructive and non-reversible practices. Cyanide is one way divers catch the fish. Cyanide is poured into the reef area which stuns the fish. The divers then use crowbars to rip open the reef to catch the stunned fish. This practice kills the reef in two ways; the poison and the physical destruction. Coral Bleaching
Coral bleaching may be one of the largest threats facing the coral reef. The photosynthetic pigment, found in the zooxanthellae, is what gives the coral most of its color. (Coral Bleaching) When the zooxanthellae is no longer able to carry out the photosynthesis, the production of reactive oxygen species are produced which damage the reef. The coral is not able to tolerate these toxic species and they spit out the zooxanthellae to avoid more damage. This process leaves the reef looking white, hence the term bleaching. The primary cause for coral bleaching is when the water temperatures increase. Coral bleaching is a natural variable however; it is questioned if the increase in global temperature is happening because of human industrial actions. Acidification
The ocean absorbs a significant amount of CO2 that is released into the atmosphere. This absorption has decreased the greenhouse gas levels which are causes of global warming. When seawater reacts with CO2, the ph balance of the water is lowered. A lower ph balance disrupts the photosynthesis that must take place for a healthy productive coral reef. Limiting the amounts of CO2 into the atmosphere will help decrease its absorption into the ocean. Because CO2 react negatively with seawater it has a negative effect on the coral reef. It is thought that one of the most cost effective ways to save the coral reef is to reduce deforestation. (Barley 2009) Increased tourism
The rapid increase of tourism accounts for issues surrounding the coral reef health. The ecosystem of the coral reef is indirectly affected by the building of resorts for the tourists. Increases in land development, to support tourism, brings with it problems such as sewage run-off, fertilizer run-off, destruction of the natural land barriers to inland areas. If the resort recognizes the necessary measures needed to protect the environment then the potential for long-term benefits to the community can be a positive factor instead of a negative issue. Coral Reef Benefits
To understand why these are a concern, the benefits of the coral reef must be identified and examined. Coral reefs provide two kinds of benefits: “economic benefits” which are tangible and “ecosystem services”. The economic benefits will be examined first. Economic Benefits
Coral reefs are estimated as having a net present value of almost $800 billion, and every year generate $30 billion in net economic benefits. The welfare value or the “willingness to pay” of coral reef are seen in several different ways. For example, the benefits of fishery are one of the most known sources to the coral reef. In developing countries, coral reefs contribute about one-quarter of the total fish catch providing food to an estimated one billion people in Asia alone. Globally, it is estimated fisheries account for $5.7 billion of the total $30 billion annually. (Conservation International 2008) Recreation/tourism
Discussed earlier were the negative effects tourism can have on the coral reef. This section will show the benefits the reef holds in terms of recreation and tourism. Coral reefs attract millions of visitors spending billions of dollars which creates economic value to the communities. Globally, recreation account for $9.6 billion of the $30 billion annually. A 2007 study estimated that the average global value of coral reef recreation is $184 per visit. (Conservation International 2008) It is estimated in south-east Florida, $256 million per year is spent from reef users. The visitors may use the reef for diving, snorkeling and fishing. (Hazen and Sawyer, 2001) If tourism is well managed, regarding the placement of the resorts and educating the staff about the importance of the reef then monetary benefits can be extremely high. Research and medicine
Coral reefs provide valuable research and education use as well. The reefs can be a source of medicines for serious diseases. The National Oceanic and Atmospheric Administration (NOAA) says nearly half of the medicines in use today have their origins in natural products, mostly derived from terrestrial plants, animals, and microorganisms. (NOAA 2010) The coral ecosystem is a source of medicines developed to induce and ease labors: treat cancer, arthritis, asthma, ulcers, human bacterial infections, and hear disease. AZT is a recognized drug used to treat HIV. The compounds in the drug are found in a Caribbean reef sponge. (NOAA 2010) Ecosystem Benefits
The ecosystem services benefits of the coral reef are difficult to quantify because they are benefits that do not have a monetary cost or cannot be sold in the markets. A healthy reef can absorb as much as 90 percent of wind generated waves. Without coral reefs, tsunamis and ocean storms can destroy coastlines. Coral reefs help decrease the erosion of the shorelines. Lauretta Burke did an analysis in 2010 that showed evidence in one meter of beach resort loss, lowers the hotel rate per night by $1.50. This may not seem like a large financial loss until it is compared to the Domincan Republic tourism industry which stands to lose $52 – 100 million in revenue over the next ten years because of beach erosion. Although destruction is easy to place a value on, the already existing natural protection is not. Studies have shown that investing $45 billion could secure nature-based services worth $4.5 to 5.2 trillion annually. (Science Daily. 2009) To maintain a marine protected area around a healthy coral reef it would cost roughly $775 per square kilometer. The same healthy reef could have an estimated value of $600,000. (Marine Protections Areas 2010) As discussed, it can be seen why it is important from an economic standpoint to make attempts to keep the coral reefs intact and healthy as well as from an environmental stand point. According to National Oceanic and Atmospheric Administration (NOAA) statistics published in an Associated Press (AP) article, roughly 19-percent of the Earth's coral reefs have already disappeared, and an additional 40-percent could be gone within the next two decades. There is a consensus with scientists that the coral reef is on a path to extinction. Further destruction to the coral reef will have devastating effects to the global economy. The global economy relies partly on the value the reef produces from tourism, medicine and food for humans. Even though coral is nature’s ecosystem, there are efforts to restore coral reef in different areas of the world. The largest restoration project is in Gili Trawangan, Lombok NTB, Indonesia. The island residents realize they must take an active part in the restoration of the reef so it can support the fishing and tourism income needed.
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