Environmental Impacts on the Great Barrier Reef

The Great Barrier Reef is threatened by human factors such as pollution, overfishing, shipping, and environmental factors such as climate change. This article discusses the three major environmental factors affecting the reef, the physical, demographical, and economical impacts of these factors, and the importance of conservation efforts.

The Australian continent, strategically positioned in the middle of the Indian Ocean and the
Pacific Ocean, is a mega-diverse landmass, with deserts, mountain ranges, rainforests, and
various other biodiversity hotspots. The Great Barrier Reef, located to its north-east is a
highly diverse ecosystem in itself, with nearly 3000 reefs and 300 islands. This is one of
Australia’s hotspots, and is a major economical boost to the nation.
The Great Barrier Reef is the world’s largest coral reef, situated in the Coral Sea. The reef
provides a large marine ecosystem, and serves as a habitat to a variety of marine species.
Coral reefs are greatly beneficial to the landmass, by protecting the shoreline. The Great
Barrier Reef has been inhabited by indigenous Australians since long. Today, it serves as a
major point in Australia for tourism and fishing. However, the stability of the reef is
threatened by human factors such as pollution due to pesticides and fertilizers, overfishing,
shipping, etc, and environmental factors such as climate change.
The reef was formed as a result of global warming in the last glacial period, and is ironically
threatened by the global warming of today. Out of the 3000 reefs, over 700 reefs are in the
risk zone, due to various factors, including coastal encroachment and development, and river
runoffs into the sea. Three major environmental factors that affect the reef are discussed
below.
1. Ocean acidification – It is the decrease in the pH levels of the ocean, doe to the
increase in carbon dioxide in the atmosphere. As coral reefs tend to calcify, the
decrease in the substance aragonite in the sea waters impacts calcification, and causes
decay. This impacts the ecosystem, leading to loss of marine biodiversity. The
increase in acidity causes an increase in the oceanic temperatures. This leads to coral
bleaching, wherein the algae living inside the coral polyps are expelled. This leads to
coral starvation, and also reduced coral reproduction.
2. Predator Attack – The corals of the reef are threatened by the “Crown of Thorns”
starfish, which is its major predator. The starfish attacks the corals by climbing on
them, and secreting digestive enzymes to digest the liquefied tissue of the coral. Even
though it is a normal predator-prey relationship, an increase in the starfish count
would pose a great risk to the reef. An increase in their population, known as an
“outbreak” could be disastrous for corals. However, human factors play a major role
in this, as reduction in the oceanic water quality, fertilizer wastes; etc can cause the
predator larvae to thrive, thus increasing their population.
3. Natural disasters – Coral reefs are extremely resilient to any kinds of tropical sea
storms and cyclones, thus any natural calamity would have a minimal impact on them.
However, as the coral bleaching is occurring at a fast rate due to increase in the
atmospheric carbon dioxide, ocean acidification, etc, there are great chances of the
collapse of the reef, which would lead to mass damage and destruction of the marine
ecosystem supported by the reef.
The environmental impacts on the reef are huge, and however inevitable, they are hastened
by the unscrupulous human activity. Increase in the atmospheric carbon levels are mainly due
to increased carbon footprint by humans. The increase in acidity of the sea waters is mainly

aggravated by humans dumping the toxic wastes into the river waters that run into the sea.
Likewise, overfishing, illegal hunting of sea-life, shipping, oil-mining, etc add to the
destruction of the reef.
Physical impact – The Great Barrier Reef is situated on the coastline of Queensland, which is
Australia’s second largest province. Due to increasing coral bleaching of the reef, the impact
of global warming and climate change that were not felt earlier is being felt now, such as
coastal erosion, increasing sea levels etc. This would in turn impact the quality of the coastal
land, making it unfit for habitation. Australia needs to reduce its carbon footprint, as an
increase in temperature by even 1°C would cause widespread loss to the reef ecosystem.
Demographical impact –Human settlements would migrate to inland areas, as the coastal
areas would be prone to floods and coastal erosions, making it unfit for human habitation.
The land would also undergo subsidence, thus causing widespread destruction to life and
property. Inhabitability in the coastal land would impact agriculture, livestock, and fisheries
to a great extent.
Economical Impact – Most of Australia’s population lies in the coastal areas. Queensland is
the third most populous Australian province. An impact to the coastline would cause
unwarranted economical impacts. The Great Barrier Reef is one of the most important
tourist’s spots in Australia, which generates a huge income every year. If it is slowly
destroyed, it would impact the economy largely. It also provides a large base for the fishing
industry, the loss of which would cause a down-spiral of the economy.
The geographical continent of Australia and the Great Barrier Reef must share a symbiotic
relationship, in order for both to survive the onslaught of global warming. However, if the
latter is exploited by the former, both the entities would get destroyed.
Climate change is for real, and the slow death of the Great Barrier Reef in front of our very
eyes is testimony to this. It is very important to conserve the reef, so that the marine
ecosystem thrives, and the geographical landmasses near the reef are protected. In order to
conserve the Great Barrier Reef, the “Reef 2050 plan” was formed by the Australian
government, to ensure protection and preservation of the reef, including short term and long
term sustainability plans. The Great Barrier Reef Marine Park which maintains the reef has
taken up various measures to protect the health of the reef, thus sustaining life in and around
the ecosystem. As inhabitants of planet Earth, it is our duty to ensure that the Great Barrier
Reef , which is one of the seven natural wonders of the world and a UNESCO world heritage
site is preserved for the future.

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