title: Predicting pre-Columbian anthropogenic soils in Amazonia.
abstract: The extent and intensity of pre-Columbian impacts on lowland Amazonia have remained uncertain and controversial. Various indicators can be used to gauge the impact of pre-Columbian societies, but the formation of nutrient-enriched terra preta soils has been widely accepted as an indication of long-term settlement and site fidelity. Using known and newly discovered terra preta sites and maximum entropy algorithms (Maxent), we determined the influence of regional environmental conditions on the likelihood that terra pretas would have been formed at any given location in lowland Amazonia. Terra pretas were most frequently found in central and eastern Amazonia along the lower courses of the major Amazonian rivers. Terrain, hydrologic and soil characteristics were more important predictors of terra preta distributions than climatic conditions. Our modelling efforts indicated that terra pretas are likely to be found throughout ca 154 063 km(2) or 3.2% of the forest. We also predict that terra preta formation was limited in most of western Amazonia. Model results suggested that the distribution of terra preta was highly predictable based on environmental parameters. We provided targets for future archaeological surveys under the vast forest canopy and also highlighted how few of the long-term forest inventory sites in Amazonia are able to capture the effects of historical disturbance.
authors.affiliation: Earth Systems Research Center, University of New Hampshire, , Durham, NH 03824, USA, Department of Biological Sciences, Florida Institute of Technology, , Melbourne, FL 32901, USA, Applied Geosolutions, , Durham, NH 03824, USA, Laboratório de Arqueologia dos Trópicos, Museu de Arqueologia e Etnologia, Universidade de São Paulo, , São Paulo, Brazil, Department of Biology and Center for Energy, Environment and Sustainability, Wake Forest University, , Winston-Salem, NC 27106, USA.
authors.forename: C H
authors.initials: CH
authors.lastname: McMichael
authors.forename: M W
authors.initials: MW
authors.lastname: Palace
authors.forename: M B
authors.initials: MB
authors.lastname: Bush
authors.forename: B
authors.initials: B
authors.lastname: Braswell
authors.forename: S
authors.initials: S
authors.lastname: Hagen
authors.forename: E G
authors.initials: EG
authors.lastname: Neves
authors.forename: M R
authors.initials: MR
authors.lastname: Silman
authors.forename: E K
authors.initials: EK
authors.lastname: Tamanaha
authors.forename: C
authors.initials: C
authors.lastname: Czarnecki
mesh_terms: D000465:Algorithms; D001106:Archaeology; D004777:Environment; D012987:Soil / Q000737:chemistry*; D013020:South America
chemical_list: D012987:Soil
keywords: Amazonia; anthrosols; maxent algorithms; modified soils; pre-Columbian impacts; terra preta