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The Ocean      Chapter 8
Resources of ocean water
Ocean water resources are quite important to people.
□ The bulk of the fishing industry relies on the water over or near the continental margins. Fish are concentrated in these areas because of the greater abundance of smaller organisms and nutrients in the water. Fish are used for food, oils, fertilizer, and livestock feed.
□ Ocean water is 96.5% water. Desalination plants can remove the 3.5% dissolved materials and produce fresh water from
11 ocean water. In some coastal areas, desalination is more eco-
Is desalination an economical way     nomical than other sources of fresh water, to obtain fresh water?
□ Scientists have been able to find many elements dissolved in ocean water. Although not all elements have yet been detected, man) scientists believe that they will eventually be found as better analytical tests are developed. At present, only sodium chloride (table salt), magnesium, and bromine are commonly derived from dissolved elements in ocean water.
□ Differences in water temperature between the surface and the depths can be used to generate electricity. OTEC (Ocean Thermal Energy Conversion) has been tried near Hawaii and offers great promise for the future.
□ Many industries use ocean water as a coolant for their machinery and equipment. The water is circulated through heat exchangers where excess, unwanted heat is absorbed.
□ For recreational purposes, the ocean's waters offer sports fishing, swimming, diving, boating, and water skiing.
□ The ocean provides a habitat for maintaining a great number of different types of life forms. This is ecologically important in order to maintain the quality of life in general and to provide a resource base for future needs. Pollution has been responsible for destroying life in the ocean. Offshore oil wells have caused much pollution and destruction of life. Chemical fertilizers are washed down rivers into the ocean. Chemical wastes from factories as well as human sewage have ended up in the ocean.
Check yourself
1. List the seven major resources of ocean water.
2. What substances are presendy derived from the dissolved elements in ocean water?