Ecosystems

American savannahs

In Latin America, the savannahs are called vàrzeas; in areas with rocky basements and little soil, the savannahs are called campo rupestre; in Brazil they are very woody, look like dry forests and are called cerrado. The tierra firme are like the African savannahs even if they are rainier and wetter during the dry season and there are also fewer fires. In the Amazonian region, there are small savannahs, which become larger north of the Amazon. The vàrzeas are, instead, open savannahs which are situated between the Rio Negro and the Xingu and around the Orinoco and which are flooded during the rainy season. Later on, as the dry season arrives, the land dries up and herbs and shrubs (i.e.Artemisia artemisifolia) quickly spring up; there are also palms (i.e.Mauritia flexuosa) or trees that resist floods and long dry spells. This mass of trees and shrubs (matas) may look like islands in a sea of dry or half-buried grass. Between Argentina, Bolivia and Paraguay, below the Mato Grosso, there is the Chacò region with abundant but irregular rains. Here grow the Copernicia palms that can resist long dry spells. In this area the fauna consists of many birds (e.g. cockerel, rhea), pumas, jaguars, hares, bats and many insects (crickets, ants, flies, etc.).