Using the resources of the world ocean

Mineral resources. The ocean floor contains a variety of mineral resources. Some valuable minerals simply lie on the ocean floor. Other resources, mainly oil and natural gas, have formed in the rocks of the seafloor. Still other resources, including salt and other minerals, are found in seawater. Scientists believe that the ocean's mineral resources could supplement the decreasing reserves of non-renewable resources on land. At the same time all agree that the ocean's wealth must be conserved so that it can be used by future generations.

Offshore oil fields account for about 20 per cent of the world's oil production today. All known offshore oil fields are located in waters above the continental shelf. Two of the more important fields underlie the Gulf of Mexico and the North Sea. The continental shelf also contains vast supplies of natural gas. Today, there are over 100 offshore natural gas platforms, many of which are located off South Asia. One platform pumps natural gas from an offshore gas field to the refinery near Bombay, India, through a pipeline.

Ocean water contains traces of all the minerals found on land. These minerals, which exist in the water in the form of salts, account for seawater's salinity, or salt content. If all the water in the world ocean were dried up, the salts would form a layer on the ocean floor 152 meters thick.

Fishing resources. The world ocean makes up the largest biological environment of our planet. Marine biologists continually discover new species of life as changing technology allows them to probe deeper and deeper into the world ocean. Each form of life is a part of a complex process in which small plants and animals provide food for larger animals living in the sea. Microscopic plants and animals called plankton make up the bottom of the food chain.

The best fishing grounds (banks) for many kinds offish are those rich in plankton. Large numbers of plankton concentrate in these fishing grounds because they have cooler water flowing through them or coming up from deeper levels. They are also shallower places in thе sea, where sunlight can penetrate below the surface. The richest fishing banks are found off the coast of Newfoundland in North America, along the west coast of South America, in the North Sea, and off the coast of Asia in the Pacific Ocean.

Fishing ranks among the world's most important economic activities. Over 5 million people make their livings by fishing. And even more people process, package, and sell fish. The total fish catch each year is enough to supply about 18 kg of fish for each person in the world. About half of this fish catch comes from the Pacific Ocean. The Atlantic Ocean provides about one third of the total.

Most fishing today is done on a large scale, using fleets of ships equipped with machines that do much of the work. Some countries, Japan and Russia, for example, send out fishing fleets that often stay at sea for two hundred days at a time. The boats in these fleets are equipped with machinery that lowers and raises nets. Refrigerating equipment freezes the tons of fish, keeping them fresh for processing. Some fleets even have ships that do part of the processing at sea. Helicopters and electronic equipment are often used to locate schools of fish.

Using this modem equipment, most fishing nations increase their fish catches each year. In one way, this is good. More food is needed to keep up with growing populations. But in another way, it is bad. The ocean world is in danger of being overfished. Fish are being taken from the oceans faster than they can reproduce themselves.

Today many people are working to protect this vital resource. Several international laws have been created to regulate the use of the world ocean and avoid disputes among countries. Several nations, for example, have signed the Law of the Sea Treaty, sponsored by the United Nations.