Notes on the Vegetation of Amazonia I. A Preliminary Note on the Origin of the Open White Sand Campinas of the Lower Rio Negro

Abstract

The origin of the open areas of white sand campinas of the lower Rio Negro is discussed. Campinas are compared with the denser campina forests or caatingas of the upper Rio Negro. It is concluded that the campinas are areas of white sand forest cleared by Indians. Evidences from pottery shards and radiocarbon dating of charcoal deposited in the soil demonstrate that the campinas were occupied by Indians of the Guarita subculture around 800 A.D. The open campina areas show a gradual succession to more closed type of campina to campina forest, the climax on the white sand. The lack of a large number of endemic species also indicates a recent origin of the open areas. Recolonization after Indian clearing is extremely slow on white sand because of limiting factors such as nutrients and excessive drainage in the dry season.