Great Barrier Reef, Australia - The world's largest coral reef

The Great Barrier Reef is one of the Australia’s most beautiful sight. It is the world's largest coral reef system. It contains an abundance of marine life. It comprises of over 3000 individual reefs and 900 islands stretching for over 2,300 kilometres over an area of approximately 344,400 square kilometres. Because of the world's most beautiful place, it is very popular among the tourists and has become the most beautiful tourists attraction. This reef is located in the Coral Sea, off the coast of Queensland, Australia. The Great Barrier Reef is visible from the outer space. It is the world's largest single structure created by living organisms. This place is blessed with the marvelous beauty of nature. The Great Barrier Reef is one of the seven wonders of the natural world. This reef structure is composed of and built by billions of tiny organisms, known as coral polyps. It was included in UNESCO World Heritage Site list in 1981. The Queensland National Trust named it a state icon of Queensland. A visitor to the Great Barrier Reef can enjoy many experiences including snorkelling, scuba diving, aircraft or helicopter tours etc. A large part of the reef is protected by the Great Barrier Reef Marine Park, which helps to limit the impact of human use, such as fishing and tourism. The reef is a very popular destination for tourists, especially in the Whitsunday Islands and Cairns regions. According to a study published by the Proceedings of the National Academy of Sciences in October 2012, the reef has lost more than half its coral cover since 1985. But according to some Australian experts, this reef can not escape now, because there is so much damage already has been done in this reef, which is now very difficult to improve. It is due to the increase in temperature in the ocean. Because of which the coral bleaching is taking place. Coral bleaching occurs when coral polyps expel algae that live inside their tissues. Coral bleaching is seriously affecting the northern parts of the reef as a result of warming ocean temperatures. As global warming continues, corals will not be able to keep up with increasing ocean temperatures.

Another major threat to the Great Barrier Reef is pollution and declining water quality. Over 90% of this pollution comes from farm runoff. Pesticides used in farming are made of heavy metals such as lead, mercury, arsenic and other toxic substances, which are released in the wider atmosphere due to soil erosion, which have harmful effects on the coral. Overfishing is also a major problem for this. Fishing impacts the reef through increased water pollution from boats. It can cause pollution by-catch of unwanted species and habitat destruction from trawling, anchors and nets. Now approximately one-third of the Great Barrier Reef Marine Park is protected from species removal of any kind, including fishing, without written permission. In November 2014, Google launched Google Underwater Street View in 3D of the Great Barrier Reef.