Destruction of Coral Reefs

In this week’s blog I will be analyzing the cause and effects regarding the destruction of coral reefs around the world.  Not only has tourism had a negative impact on coral reefs such as, the Great Barriers Reef, but these impacts have caused a negative decline in ecotourism to these areas over time. Coral Reef tourism is a major source of revenue for many countries and without these reefs countries are losing a huge profitable sector of the tourism industry. The Great Barrier Reef Marine Park Authorities is one example where their 2005-2006 income was approximately 1.259 million dollars less than the year before (Coral Reef).  If coral reefs continue to be negatively impacted the countries that are highly dependent on tourism will experience a huge decline in tourism revenue and a large loss in jobs and economic growth for many communities.  This brings me to my next point of what are the negative factors that is causing the destruction of coral reefs? Coral Reefs are an essential component to the balance of the entire oceanic ecosystem.  Coral Reefs act as a barrier between the island shore and the open ocean.  Therefore if coral reefs are left to die because of human impact then there will be nothing to block the organisms from the deep sea to come into shore. The destruction of Coral Reefs has been caused by a number of factors over a period of time. These factors include pollution, over-fishing, climate change and other human pressures.

Pollution, being one of the major influences in the destruction of coral reefs, has many direct and indirect influences.  Deforestation is one example of an indirect influence on the destruction of coral reefs because sediment runoff from deforestation can bring many toxic components into the coral ecosystem.   Mining and Farming also carries the same negative impacts but on a greater scale because of the pesticides and fertilizers used. The pesticides and fertilizers used add nitrogen and phosphorous into the ecosystem which causes massive growth in algae.  This growth in algae leads to a depletion in the oxygen available for other creatures, reducing the biodiversity of that ecosystem.  Human, land based, pollution has threatened 22% of the world’s coral reefs (Puglise 2007). 

The next major factor which is causing the threatening and destruction of coral reefs all over the world is the over-fishing in areas close by to and in coral reefs. The first part to understand why overfishing causes negative impacts on coral reefs is to understand that each specific plant and animal species has a significant role and function in the coral reef ecosystem. Each organism requires a certain environment, nutrients and is dependent on other organisms within the reef system (The Coral Reef Food Chain).  When you overfish an area or a certain type of fish, no matter it being in a reef or not, you involuntarily create a domino effect on that ecosystem all the way down the food chain.  These effects can be directly seen through fish size, abundance, species composition and diversity within reef ecosystems (Coral Reefs).  In order to help save our coral reef ecosystems we must help stop the overfishing of reefs through designing effective conservation programs, understanding the drivers of overfishing (supply and demand) and putting large consequences/fines on the overfishing and destruction of coral reef ecosystems.

The next factor that leads to the overall depletion of the world’s coral reef ecosystems is climate change.  Climate change has had a significant role in the depletion on the worlds coral systems.  Climate change is the result of global warming which is caused by the build up of greenhouse gases in the atmosphere.  These greenhouse gases trap in solar radiation to keep within the atmosphere of the earth, thus causing the melting of polar ice caps and raising of the sea level.  This causes a number of problems but for coral reefs in specific the increased UV radiation hinder the ability of the plants and algae to photosynthesize.  The ending result is that there is now a lot less energy available overall in the marine ecosystems.  One example of fatal impacts in which climate change has had on coral reef ecosystems is coral bleaching.  “Coral bleaching” is caused by the increase in warm temperatures, higher UV radiation, sedimentation, and reduced lighting levels.  When temperatures stray too much, the algae disconnect from their host cells because they lose their adhesive cell function (Tchernov 2004).  The result is that the corals become bleached and are left colourless and without the ability to produce energy.