Geography of South America world by drainage area—the Amazon River and the more southerly Paraná River. The other major river of this central lowland is the Orinoco River, which has a natural channel linking it with the Amazon. Most of this central lowland is sparsely populated because the soils are heavily leached, but in the south is the very fertile pampas of Argentina—one of the world's major food-producing regions where wheat and beef cattle are pre-eminent. The natural vegetation of the northern lowlands are either savanna in the northern "llanos" and southern "campos", or tropical rainforest throughout most of the Amazon basin. Efforts to
South American Championship of Champions admitted only the previous Copa Libertadores champions, and by FIFA's and Conmebol's sites. The aim of the organizers was to invite the champion of the most important competition of each South American country. Most notable in the competition were the host Colo-Colo, the Alfredo Di Stéfano-inspired River Plate, the Atilio García-inspired Nacional, and Vasco da Gama, the respective representatives of Chile, Argentina, Uruguay and Brazil, four countries whose clubs would go on to become the dominant powers of South American football, aggregately winning all Copa Libertadores from 1960 to 1978 and over 90% of the Copa Libertadores from 1960 to