Great Barrier Reef – the world’s largest coral reef, located off the coast of Australia. It is the largest single structure on earth created by living organisms, visible even from space (as a white streak against the blue ocean).
Origin and main features
Development of the Great Barrier Reef began in front of about 18 million years ago. Age reefs is estimated at some 20 million years, and some of its parts, even at 45.5 million years. In the current phase of development, which has lasted 8,000 years, new layers are built on “old” foundations. The barrier is located at different distances from the shore, ranging from 15 to 200 km, and extends over an area of over 344,000 km ². Great Barrier Reef includes about 3,000 individual reefs and 900 islands that are surrounded by reefs, forming a coastal island. Width of the reef ranges from 2 km to 150 km. Studies conducted on the reef showed that the thickness of the layer forming the coral it exceeds 500 m.
In contrast to the middle part, which are scattered coral, reefs in the north and south lie close together. In the northern part, where mangrove forests are growing, there are many swamps.
Between the Great Barrier Reef and coastal lagoons stretch. This area of shallow water, which rarely exceeds 100 m depth, muddy layer covers protected by offshore reefs. From the sea, reef slope descends steeply to thousands of meters into the sea. Reef at this point is exposed to waves and winds. Coral growth is fastest here. At the same time in places where the waves and temperatures are extreme, the coral lose the greatest amount of building material. Much of the loose material is re-connected and creates a “new rock”. Rafa is subjected in this way the constant process of destruction and reconstruction.
Formation of Barrier Reef
The most commonly used name of a coral reef, but there is also the name of “living rock”. Reef is made up of thousands of creatures from anemones family – polyps, as well as other organisms such rafotwórczych bryozoans, molluscs, foraminifera and algae, forming the shaft or underwater ridge. Polyps form limestone skeletons that can be easily separated from the rest of the animal’s body. During the reproductive polyps, reef grows across and up. Polyps are connected with the cordage of living tissues, which contributes to strengthening the structure. Calcareous seaweed that look like red balls of cotton wool, are important elements that make up the reef. They produce limestone, which strengthens the reef. Other seaweeds living virtually on the slopes of the reef, producing a kind of “mortar”. In this way, the community creates a powerful structure, where only a few uninhabited parts of the limestone skeletons of dead corals. Each species has its own pattern of coral growth, which is why it is encountered such a variety of forms – from the hills, and large panes of plate, the surfaces, branches and structures in the form of horns.
Coral reefs are in relatively shallow coastal waters are międzyzwrotnikowej. Is built of limestone, which form the skeletons of dead corals. They live on them all the colonies of other organisms and feed numerous species of animals.
It’s a beautiful place full of different species of fish, molluscs and plants. In addition to the approximately 1,500 species of fish on the reef is alive 5000 species of molluscs and 400 species of coral and 500 species of seaweed. Larger islands are covered with dense tropical vegetation. Great Barrier Reef is one of the major tourist attractions in Australia.
From 26 October 1981, as a marine park (Great Barrier Reef Marine Park), protected, inscribed on the UNESCO World Cultural and Natural Heritage. The park area, protected by UNESCO, is 346 000 km ². (Coral Sea, Great Barrier Reef and the Queensland rainforests.)
Great Barrier Reef off the coast of Queensland is the largest, most diverse and beautiful reef in the world kolarową. It is also one of the youngest reefs – some of its sections now account for only 500 thousand. years. Stretches for more than two thousand. km from the city of Brisbane to zatoku Papau.
Building blocks of coral skeletons of dead corals are. On the Great Barrier Reef is made up of about 3 thousand. coral reefs and small islands with very diverse areas – from just a few meters to 50 km ². Great Barrier Reef stretches 330 km into the Pacific. Its total area is 259 thousand. km ².
Great Barrier Reef is famous for its corals, although they represent only 1 / 10 surviving organisms here. On the reef there are at least 350 species of various shapes, sizes and colors. They require the right environment. Reefs are formed only in the saline and warm waters (temperature maintaining not less than 22 ° C). The water must contain enough oxygen, so it can not be stagnant water, and it must be sufficiently clear that the sludge did not block the digestive system of coral.