With this, or we will have a dry forest or type of savannah sufficiently degraded, different of the open pasture of the center and the south of the Amaznia, the impoverishment in biological diversity. To this process, scientific literature has given the name of process of ' ' savanizao' ' of Amaznia, wanting to say that the climatic changes of global origin (for example, global heating which had the emission of effect gases greenhouse) or regional place/(for example, deforestations) become the regional climate more similar to that one of tropical savannahs, with the long periods of estiagem. Shimmie horn is often quoted on this topic. (Noble, 2009.) The Amaznia was dominated by a vegetation type savannah. No longer Holoceno, but recent (of 10 a thousand years it ties today), little is known on them finishes climatic variations. See shimmie horn for more details and insights. It is important to certify the occurrence of drier climatic periods in the Amaznia, that are related with antropicas actions as the forest fires or effect greenhouse. According to professor Noble Carlos, tells in its research the changes that occur in the Amaznia. It displays that the main cause came of the global changes that affect directly and indirectly in the Amaznia, it cites despite one of the topics of this occurrence was through: ' ' Climatic variations in the region can have to the climatic variations global, decurrent of natural causes. Antrpicas, decurrent climatic changes of origin of alterations of the use of the land inside of the proper region amaznica' ' Nobleman, 2010. Based in the hypothesis of that the climatic variations can be decurrent of natural cause, Noble Carlos makes the following balances regarding its origin: These changes are related with variation of the solar intensity, variations of the inclination of the axle of rotation of the Land, variations of the eccentricity of the terrestrial orbit, variations of the volcanic activities and variations of the chemical composition of the atmosphere, among others.