Pre-Columbian vegetational and fire history in western Amazonia: Terrestrial soil phytolith and charcoal evidence from three regions

The extent to which pre-Columbian human societies occupied and significantly impacted Amazonian environments have been long-standing questions and are currently under active discussion. Data are particularly limited from terra firme forests, formations away from watercourses that occupy over 90 % of the Amazon Basin. This paper investigates pre-Columbian influences on fire and vegetation in three regions of the western Peruvian Amazon through phytolith and charcoal analysis of terrestrial soils. One region in the Tapiche-Blanco watersheds was not previously studied. In the other two regions, the Los Amigos Biological Station and between the towns of Iquitos and Nauta, previous phytolith research was expanded to study in more detail forest composition and cultural palm usage through time. Our results indicate the diverse forests in these regions remained intact and were little affected by human forest clearing and agriculture with annual seed and root crops during the past 2000–5000 years of prehistory. Cultural palm enrichment is indicated in limited areas within each region studied, and usually occurred in riverine environments. The accumulated evidence from a number of different proxies indicates the persistence of diverse, forest-dominated pre-Columbian landscapes in western and parts of central Amazonia studied to date.