The Brazilian Biome Map and location of Research Centres. The Amazon region covers 40% of the surface of South America and 5% of the surface of the world, and 61% of its territory is in Brazil. It has the largest hydrographic network on earth, covering 20% of the worlds fresh water reserves and shelter the largest number of life forms on earth; the Atlantic forest (seasonal semideciduous forests) is the third largest Brazilian biome that stretches for about 4 000 km along the Atlantic coast between Rio Grande do Norte and Rio Grande do Sul; the "Caatinga" (semiarid steppe of Northeast Brazil) is located on the north-east coast is the largest dry forest region in South America and characterized by a semi-arid climate, low and unregular rainfall, fertile soils and an apparently dry vegetation; the Cerrado (Brazilian Savanna) is located on the large plateau that occupies the central highlands. Influenced by the four surrounding biomes, the fauna and flora of the Cerrado is extremely rich and the climate is hot and semi-humid; the Pantanal (Brazilian wetlands) is located in the watershed of the Upper Paraguay Rivers the largest area of fresh water marshes in the world, shared between Brazil (60%), Bolivia and Paraguay. The Pampas are the fertile South American lowlands in the southernmost end of Brazil, the climate is mild and contain unique wildlife because of the different terrains around it.