Abstract: Massive efforts are being made by public and private institutions to protect the Amazon environment from being destroyed by rural development and poor management practices. Much of Amazonia is considered by conservationists and environmental groups to be classic examples of "pristine" and "natural" environments. Biodiversity, often used as a measure of the "health" of natural environment, is determined by long-term human activities in the tropics. Archaeological and ecological investigations now show that the human impact on Amazonian ecosystems was massive and is possibly responsible for much of the structure and content of present faunal and floral communities. The seasonally flooded savannas, gallery forests, and forest islands of the Bolivian Amazon were radically transformed by generations of prehispanic farmers. Between 1990 and 1996, valuable information was gathered on two forms of earthworks, raised fields and earthen causeways, that dominate the anthropogenic landscape. Implications regarding human settlement, socio-political organization, sustainability, and spatial patterning of these earthworks are discussed. Any attempt to understand the present situation in Amazonia and to address contemporary issues of conservation and sustainable development must include the long-term perspective of archaeology and historical ecology.