In addition to their biological resources, the world’s oceans are rich in minerals and sources of energy that can be exploited by human beings.
► Resources exploited today:
Extracted from the sea since antiquity, salt was initially only used to preserve and season food. Today, it has become a raw material for the chemicals industry. Its scientific name is sodium chloride. How is it made? As a result of erosion*, the sodium in rocks is carried away by rivers to the sea. Seawater contains many elements such as magnesium and chlorine; sodium combines with chlorine to from sodium chloride. On average, seawater contains 35 grams of salt per kilogram of water. Seawater is evaporated in shallow basins in solar salt ponds to extract the salt. Solar salt ponds are located in regions where the climate is dry and warm, adjacent to the North and Mediterranean seas for example, and also in temperate zones, such as along the Atlantic coastline of France. One third of the world’s salt is extracted from seawater and the rest come from many underground deposits, which are the remains of seas that no longer exist.
Fifty years ago it was believed that mining manganese and other precious metals was going to become the new source of wealth to be taken from the oceans. The floors of the ocean deeps are strewn with multi-metal nodules-stones loaded with many metals. But since then we have learned how to extract these metals easily from the earth, and in great quantity. For the moment, sea water principally supplies us with bromine and magnesium. Bromine is produced from sea salt primarily in the united states, the gulf of Mexico, Canada, France and Japan. Magnesium is obtained from the ‘first stages waters’ of solar salt ponds primarily in the gulf of Mexico.
Oil and gas
Oil and gas (hydrocarbon*) stored several hundred or several thousand meters beneath the ocean floor are extracted using costly, heavy machinery (platforms, hydro- carbon extraction systems). Two-thirds of the ocean’s hydro-carbon deposits, are deposits are located off the shores of Middle Eastern countries and are especially concentrated in the Persian Gulf. At present, marine hydrocarbon deposits supply 30 percent of the total volume of oil produced worldwide and 10 percent of the world’s natural gas supply.
Desalination plants transform seawater into fresh, potable water. Now a days use this method to obtain the majority of their water supply. There are two principal ways to remove salt from seawater: either by distilling it, whereby the water is heated until it evaporates and thus separates from the salt, or by filtering it, whereby the water is poured through very fine, highly perfected membranes. Even though distillation is the technique most widely employed today, filtering could become at least as profitable as efficient in less than fifteen years.
Strong tides are the source of considerable energy. This energy can be converted into electrical power at plants that harness tidal energy to drive turbines and generators. The first type of this plant was built in 1967. But this energy has not been developed as was initially hoped due to competition from nuclear power plants, which are less expensive, and the limited number of sites along the coast where tidal variations are sufficiently great to install tide driven power plants.
The energy created by waves is called mechanical energy; it can be harnessed by floating installations placed on the water, or by shore installations. Plants of this type have been installed around the globe, and in particular in Japan, China, India, Norway and Great Britain. Converting this inexhaustible energy supply into electricity is pollution free. There is only one problem: the operating costs for these plants are still very high.
In 1977, the French deep-diving submersible Cyana discovered strange mineral structures that looked like termite mounds at a depth of 3,000 meters in the pacific off the Mexican coast. These were hydrothermal sources, with temperatures that can exceed 350ºC. Shellfish and enormous worms were found living close by. Today, research into the ocean abysses is speeding forward; we know that bacteria* live without any problem in this hot environment completely deprived of light. We’re just beginning to understand. Maybe some day these ‘super-bacteria’ will help us understand the origins of life itself.
The 200000 species of invertebrates (fish, mollusks, and crustaceans) and algae identified so far contain countless chemical substances whose composition is still Unknown but which may be beneficial to health. The pharmaceutical industry has been studying them for the past forty years to discover whether they can be used to treat tested for treating cancer. Although considerable, the funds set aside by governments and private industry for marine observation and research to make advances in the field of pharmacology are often insufficient. The IOC helps governments by keeping them up to date in new techniques.
Intense research in the genetic material of marine species is currently being carried out by the pharmaceutical and biotechnology industries. This research is leading to many discoveries and new products.
The vedio of ocean Resources: