A Bluff Model of Riverine Settlement in Prehistoric Amazonia

Abstract

Abstract In Amazonia, prehistoric settlement was especially concentrated along the major rivers. This has been explained by the superior soil and wildlife resources of the floodplain (várzea) compared to the interfluve uplands (terra firme). However, the floodplain is a high-risk habitat because of regular and periodic extreme flooding of even the highest terrain. A bluff model is proposed arguing that most settlement was not in the floodplain but rather on the valley-side bluff tops adjacent to active river channels. Subsistence was a multistrategy utilizing floodplain playa (beach) and levee soils and aquatic wildlife periodically in combination with more stable bluffedge gardens, agroforestry, and hunting. That permanent and semipermanent cultivation systems were established on the poor bluff soils is evidenced by archaeology, ethnohistory, paleoecology, and zones of anthropogenic soils (terra preta). However, bluff occupation was sporadic rather than continuous, with large settlements mostly located where main river channels impinged against bluffs. This pattern persisted with colonial missions, and it continues today.