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
Sport in Uruguay union team, more commonly known as the "Los Teros" (southern lapwing), represent Uruguay at the international level. The team is governed by the Unión de Rugby del Uruguay, and are the second highest ranked team in South America, after Argentina, at 20th in the world. Uruguayan rugby players such as Pablo Lemoine and Rodrigo Capó Ortega have enjoyed success in the professional European leagues. Tennis is a mildly popular sport in Uruguay, although Uruguayan players have not been as successful as the Argentinian and Brazilians ones. Marcelo Filippini is Uruguay's most successful player, winning five singles titles, reaching the quarterfinals