The University of Kansas By Author Lilian Rebellato Submitted to the graduate degree program in Department of Geography of the University of Kansas in partial fulfillment of the requirements for the degree of Doctor of Philosophy. ________________________________ Chairperson William I. Woods ________________________________ Stephen Egbert ________________________________ Peter Herlihy ________________________________ Rolfe D. Mandel ________________________________ Ivana Radovanovic Date Defended: 10/25/2011 ii Dissertation Committee for Author Lilian Rebellato certifies that this is the approved version of the following dissertation: Amazonian Dark Earths: a case study in the Central Amazon ________________________________ Chairperson William I. Woods Date approved: 10/25/2011 iii Abstract This investigation derives from research conducted over several years and contributes to the understanding of the differential occupational dynamics and use of space in pre-Colonial Amazonia. The goal of this study is to use traditional chemical and physical soil analytical methods to understand the archaeological site formation processes in the study area. Many of the sites in Amazonia have terra preta and terra mulata anthropogenic soils, that is, soils that are highly fertile and resilient, with elevated concentrations of pottery, charcoal, burials, and lithic and faunal remains. Because these soils have high pH values, the organic materials are well preserved for a tropical forest context. Testing a hypothesis about the use of these soils for food production during the pre-Colonial period was the main goal of this geoarchaeological research; the chronologies of occupation as well the size, shape and permanence of the villages during the pre-Colonial period are also included. The results show that the last occupational group – associated with the Guarita subtradition that occupied the site around 900 AD – discovered the fertile properties of these soils and reorganized them in order to improve their crop production. The evidence for this conclusion comes from chemical and physical analysis of the soils, which revealed a greater concentration of carbon (C) in the surface stratum of the site, while the amount of phosphorus (P) decreases with depth in that stratum. Moreover, a great and rapid spread of terra preta in the site surface iv corroborates these findings. Therefore, I deduce that a population around 900 AD introduced a different way to use the land; they farmed larger field areas for food production, decreasing the amount of P in the soil, because it was available for plants, but not of C, because carbon is mainly concentrated in black charcoal and is thus not available for plants. Slash- and-burn agriculture was the human action responsible for generating the black charcoal, and was used to increase soil fertility during crop production. The apparent change in land-use by the last group that occupied the site is related to the Amazon Polychromic Tradition (APT) that is associated with the Tupi expansion. v Acknowledgements First, I would like to acknowledge CNPq (Brazilian Governmental Research Council), for the scholarship without which this work would have been impossible, and the Chairman of my committee, Dr. William I. Woods, who advised me and furnished the conditions for full development of this research. To all members of my committee, Dr. Stephen Egbert, Dr. Peter Herlihy, Dr. Rolfe D. Mandel, and Dr. Ivana Radovanovic, I offer many thanks for their patience and useful comments during this process. Several people connected to research laboratories in Brazil and the USA also provided important conditions for the analyses, including Dr. Wenceslau G. Teixeira from Embrapa (Empresa Brasileira de Agropecuária), who also helped me a lot with the statistical analysis, as well as Donald Meyer, President of Rock River Laboratory Inc., and his family, who provided equipment and trained people to assist me. My family, my mother Narzira and sisters Luciana and Livia, played a very important role during this work, giving me emotional support even during the hardest time when fate took my father, Luiz Rebellato, from us. Dr. William Balée, Dr. Robert Carneiro, Dr. Charles Clement, Dr. William Denevan, Dr. Clark Erickson, and Dr. Siu Mui Tsai provided valuable comments and friendship. Dr. David Robinson invited me for an important plenary presentation at the AAG congress in Seattle. The Central Amazon Project leader Dr. Eduardo G. Neves allowed me to carry out investigation in the research area, and my friend Jago J. Birk patiently helped me with data collection and geostatistical analyses. Friends who have been part of my academic development since my Masters—including Suzana Ketelhut, Fernando Dantas, and Andrea Borghi in Manaus, Alexandre Salles in São Paulo; Trisha Jackson and family and Aida Ramos in Kansas; and Monica Barnes and David Fleming in New York—were always present during the vi Ph.D. process, and I thank them very much for all of their support. Colleagues in my new job position, including Denise Gomes, Bernadino Figueiredo, Lauro Barata, Anne Daniel, and Claide Moraes, collaborated with this research, and I owe especial thanks to the Directory of the University of Oeste do Pará, the Chancellor Dr. José Seixas Lourenço, and to Drs. Tereza and Marcos Ximenes, who are supporting the finalization of this work. I gratefully acknowledge ongoing support for my research and future work from several people other universities as well: Dr. Denise Schaan, Sanna Saunaluoma, Dr. Alceu Ranzi, and Antonina Barbosa. Without the help of Dr. Manuel Arroyo-Kalin, Leandro Silva, Manoel Taveira, Stevao Souza, and Adriana Meinking I would not have completed all the sample collection or analyses necessary. Thanks to all the technical support staff from University of Kansas, especially Kim Glover, who always helped me with computer support, and Beverly Koerner and Beverly Morey who provided essential information from the department. Finally, thanks very much all those who helped me in a positive way with collaboration and friendship. Last (but not least!) is the Wizard of Oz who gave me a bicycle, which allowed me to finish my credits at the University of Kansas. vii Table of Contents Introduction .................................................................................................. 1 Objectives .............................................................................................. 5 Overview ...................................................................................................... 9 Landscape ........................................................................................... 10 Two Flood Events in the Arid Holocene ........................................ 15 River System ....................................................................................... 16 Floodplains ................................................................................... 20 Uplands ............................................................................................... 22 Soils ..................................................................................................... 24 Vegetation ........................................................................................... 26 Climate ................................................................................................ 27 The Diversity in the Amazon ...................................................................... 28 Biodiversity .......................................................................................... 29 Cultural Diversity ................................................................................. 30 History of Human Occupation ............................................................. 32 Pleistocene-Holocene Transition ......................................................... 33 Early Holocene .................................................................................... 35 Middle Holocene .................................................................................. 36 Late Holocene ..................................................................................... 40 viii History of Occupation During the Late Periods .......................................... 51 Arawak Diaspora .......................................................................... 53 Tupi Expansion ............................................................................. 55 Migration or Expansion? ............................................................... 59 History, Linguistics, and the Origin Center ................................... 60 The Amazon Polychrome Tradition .............................................. 62 Current Context ............................................................................ 64 Landscape and ADE .................................................................................. 70 Anthrosols ........................................................................................... 72 Amazonian Dark Earths ............................................................................. 77 History of the Amazonian Dark Earth Research .................................. 78 Distribution of ADE .............................................................................. 83 Classification ....................................................................................... 84 Chronology .......................................................................................... 85 Current