THE SHAPE OF SOUTH AFRICA
The face of South Africa represents a history of upliftment and erosion, on a complex geological base. Some of these features originated in an early geological period when the continents of South America, Africa, Australia and Antarctica were joined and known as Gondwanaland. Over a period of millions of years, the forces associated with continental drift resulted in the movement of continents into the positions they occupy today.
One of the most prominent features in South Africa resulting from the separation of the continents is the linear pattern of the Cape Folded Mountains, represented by the Langeberg, the Swartberg, the Outeniqua and the Cedarberg. They extend from the large half-moon shaped bay at Port Elizabeth in the east to the northerly extreme of the Cedarberg at Vanrhynsdorp.
Another prominent feature of the South African landscape is the Great Escarpment, stretching from Springbok in the north-west, southwards to Sutherland, and then eastwards and northwards past the Lesotho Highlands to the Soutpansberg in the north. The Great Escarpment is most visible in the Drakensberg range stretching from Lesotho into Mpumalanga and the Northern Province.
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Gill nets Gill nets or drift nets, often described as "walls of death," have a devastating impact on marine resources worldwide and have caused an international outcry. Gill nets are fine nets made of monofilament nylon.
The gills of the fish are caught in the fine mesh of the nets, with the result that the fish drown. Nets can be as long as 65 kilometers and as deep as 15 meters. According to estimates, more than 1 500 vessels set 50 000 kilometers of netting in the oceans each day. These nets are often set across known migratory routes of target fish. Only a few species such as tunny, swordfish and squid are targeted. However all marine life caught in the nets ultimately dies, including dolphins, small whales, seals, turtles and sea birds. To aggravate matters, pieces of netting often break away and float around for many years, causing numerous fish that swim into them to drown. The Japanese government estimates that about 16 km of netting is lost every night in the Northern Pacific.
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