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| Sunday, 3 October 2004 |
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Junior Observer |  |
| News Business Features Editorial
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Surprises of the deep
The ocean is home to millions of plants and animals and it indirectly supports our existence. You may be surprised to learn that just like on land, the ocean depths also have mountains, hills, valleys and deep trenches. They are all concealed deep beneath the flat looking surface of the seas, which are rough or calm depending on the weather. The sea has an average depth of nearly four km. and the sea water has an average temperature of about 40 degrees C. Where do you think the deepest point on earth is located? In the depths of the oceans. The Challenger, deep in the Mariana Trench, is the deepest point with a depth of more than 11 kilometres, which means it can easily engulf the mighty Himalayas. Now isn't that fascinating? The oceanic crust is made mostly of basal-like rock while the continental land masses are formed by granite. The thickness of the ocean crust may vary from 10 to 65 km. The mantle largely consists of molten lava (Magma). Scientists study the ocean depths using submersibles which are self-contained vehicles with their own power sources for propulsion, sampling and video recording. One such submersible scientists used to study the ocean depths in the Alvin, which can accommodate two scientists and a pilot. An instrument called ANGUS (acoustically navigated underwater survey system) is towed behind the Alvin to map the area under study. Alvin made several dives to the 2,500m deep Galapagos Rift, which lies 960m west of Equador. And the discoveries made were unbelievable! There were communities of animals: clams, mussels, tube worms and crabs living in these depths around the vents in the rifts caused by the continental drift. How these creatures sustain themselves at such depths was a fascinating question. We all know that animal life, both territorial and aquatic, is basically supported by plants, which depend on sunlight for their existence. The animal communities in the vent however did not get any sunlight, yet they were existing. Giant tube worms (upto three metres long and several centimetres in diameter) and clams with red blood and beef-like flesh lived in these vents. Some of the worms discovered here had no mouths or digestive systems. So, how did they survive? With the help of organic matter falling from more productive surface waters. A special kind of food prepared by bacteria which forms in these vents is used as food to survive. This bacteria was found in the tissues of the giant worms. Hydrothermal vents with characteristic communities have been discovered at other sites also. The communities are rich and diverse in nature. There are symbionts, grazers,filter-feeders and predators among them. The biomass of a vent community maybe 500-1000 times greater than that of a typical deep sea community. Of the 300 or so species identified, more than 95 per cent are new to science. Many hardly resemble any of their terrestrial or shallow water counterparts, but rather look like ancient species. One wonders how many such surprises are still hidden by the sea in her depths.
Who invented the aqualung?
It was during World War II that the aqualung was invented by the famous French diver, Jacques Cousteau while fighting with the French resistance. Today divers can swim quickly with little effort, wearing frog-like fins, thanks to the aqualung which supplies air naturally as the diver breathes in and out.
World's first underwater robot
Named ThaiXPole, the 50 - kilogram robot is a metal cubic frame surrounding an array of equipment. It measures 120 cm in height, 90 cm in width and 45 cm in length. This underwater robot is capable of swimming as deep as 50 metres and is equipped with highly sensitive sensors .ThaiXPole is different from other home made robots because it can withstand temperatures up to - 40 Celsius. According to Marine Biologist Dr. Woranop Wiyakarn, this is something that has never been achieved before. |
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| Politics | Produced by Lake House |
The Planet Earth we live in is more water than land with 71 per cent of
it covered in water. The oceans, in fact, form a thin film of water on the
globe, and it is 12,756 km in diameter. It is important then, to know more
about the ocean and the surprises of the deep....
The aqualung which consists of portable breathing equipment gives
divers great freedom to explore underwater. Before the aqualung was
created divers had to wear suits which were very bulky and restricted
movement - tethered by cables to boats on the surface.
A remote-controlled robot that will be used to conduct underwater
research in the South Pole exploration has been designed and tested by a
Thai research team.
