摘要：Summary The origins 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. Evidence from pottery shards and radiocarbon dating of charcoal deposited in the soil demonstrates that the campinas were occupied by Indians of the Guarita subtradition around 800 A.D. The open campina areas show a gradual sucession to more closed type of campina to campina forest, the climax on the white sand. Recolonization after Indian clearing is extremely slow on white sand because of limiting factors such as nutrients and excessive drainage in the dry season.
其他摘要：Summary The origins 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. Evidence from pottery shards and radiocarbon dating of charcoal deposited in the soil demonstrates that the campinas were occupied by Indians of the Guarita subtradition around 800 A.D. The open campina areas show a gradual sucession to more closed type of campina to campina forest, the climax on the white sand. Recolonization after Indian clearing is extremely slow on white sand because of limiting factors such as nutrients and excessive drainage in the dry season.
