LAURA ANNE GERMAN the Dynamics of Terra Preta
Total Page:16
File Type:pdf, Size:1020Kb
LAURA ANNE GERMAN The Dynamics of Terra Preta: An Integrated Study of Human-Environmental Interaction in a Nutrient-Poor Amazonian Ecosystem (Under the Direction of TED L. GRAGSON) This research explores human-environmental interactions in a nutrient-poor (oligotrophic) environment, the blackwater ecosystems of Amazonia. I focus in particular on the modifiability of ecosystem properties by traditional groups and the enhancement of subsistence options within these “anthropogenic” landscapes. The co- occurrence of naturally-occurring terra firme soils (Latosols) and Indian Black Earth, a more fertile anthrosol resulting from the semi-permanent settlement of Amerindian groups, provides a unique opportunity for analyzing: 1) the role of anthropogenic modifications of the environment in conditioning human adaptive processes, and 2) the plasticity of human-environmental interactions within nutrient-poor environments. Two years of cognitive, behavioral and biophysical data collection among caboclo families farming both Indian Black Earth and non-anthropogenic Latosols provides the groundwork for the analysis. My inquiry into the role of the anthropogenic environment in conditioning human adaptive processes includes a characterization of the anthropogenic environment and an identification of distinctive adaptive processes resulting from environmental differences. To research the plasticity in human- environmental interaction, I analyzed the degree to which pedology and cultivation systems on Black Earth depart from the “referent” Latosol cultivation system (plasticity as practice and outcome), as well as the factors that constrain and enable this divergence (plasticity as theoretical construct). Both quantitative (soil sampling, botanical quadrants, time allocation studies, frame analysis) and qualitative (soil horizon descriptions, semi- structured interviews, participant observation) methods were employed. Results show how anthropogenic modifications of the environment condition cognitive, behavioral and biophysical manifestations of adaptive process. This is true for ethnopedological domains, perceptions of productive opportunities and differences, cropping associations, nutrient management activities and fallow dynamics. Secondly, both the ecosystem and associated subsistence manifestations exhibit significant plasticity in distant blackwater environments. While soil fertility varies geographically, average values of exchangeable calcium, available phosphorus and Base Saturation are invariably the most plastic parameters and similar crops may be grown in Black Earth and non-anthropogenic soils in each setting. This suggests that divergent uses result from other, non-biophysical factors. Evidence that Black Earth becomes important as traditional diets change, exotic crops become available and market influences take hold suggest that important historical contingencies (technological, political-economic, cultural) underlie the plasticity of human-environmental interactions. Yet environmental constraints are also evident in the inability of contemporary groups to form Black Earth, in the constraints posed by an oligotrophic environment on intentional or fortuitous soil enhancement and in cultivation-induced soil degradation. The Structuration Model of Human Ecosystems was developed to explicate this ension between ecological praxis and ecosystem constraints in human ecosystems. INDEX WORDS: Human ecology, Caboclo, Amazon, Indian Black Earth, Terra Preta do Índio, Rio Negro, Anthrosols, Blackwater ecosystems, Shifting agriculture THE DYNAMICS OF TERRA PRETA: AN INTEGRATED STUDY OF HUMAN-ENVIRONMENTAL INTERACTION IN A NUTRIENT-POOR AMAZONIAN ECOSYSTEM by LAURA ANNE GERMAN B.S., Cornell University, 1991 A Dissertation Submitted to the Graduate Faculty of The University of Georgia in Partial Fulfillment of the Requirements for the Degree DOCTOR OF PHILOSOPHY ATHENS, GEORGIA 2001 © 2001 Laura Anne German All Rights Reserved THE DYNAMICS OF TERRA PRETA: AN INTEGRATED STUDY OF HUMAN-ENVIRONMENTAL INTERACTION IN A NUTRIENT-POOR AMAZONIAN ECOSYSTEM by LAURA ANNE GERMAN Approved: Major Professor: Dr. Ted L. Gragson Committee: Dr. Ben Blount Dr. Pete Brosius Dr. Ron C. Carroll Dr. Larry West Dr. Frank Golley Electronic Version Approved: Gordhan L. Patel Dean of the Graduate School The University of Georgia May 2001 For Mamá, who taught me to fight for the things most dear, and whose courage and tenacity are exemplified in her most recent fight – for life itself. DEDICATION For the families of the Negro, Urubú and Canoas Rivers, and for other friends and colleagues of Amazônia, for their friendship, patience and selfless assistance: Qualquer trabalho intensivo . seja de rio ou de terra firme, destinado ao mercado ou para o consumo da família, feito com as mãos ou com a cabeça . precisa de conhecimento e dedicação. O trabalho de cada um de nós precisa de conhecimentos básicos e de empenho para poder se encaminhar. Contudo, para uma estrangeira poder entrar em um novo pais, em uma terra desconhecida, e levar para a frente um trabalho baseado só em livros e estórias, não é o suficiente o estudo, nem a dedicação ao trabalho. Mais importante ainda é a recepção das pessoas, a vontade desinteressada de compartilhar os conhecimentos e as experiências próprias com uma pessoa nova, a apertura das portas e cozinhas e quintais para fazer-a sentir “a vontade” e com barriga cheia, o esforço de fazer-a sentir entre família quando a sua família esteja longe. Para tudo isso, estou profundamente agradecida a todos vocês. Através de dois anos nos quais eu tive a oportunidade de conviver com várias famílias e professionais da região, eu aprendí a respeitar a dedicação de cada um de vocês às suas professões, famílias e comunidades, e de apreciar o amplo conhecimento que faz possível que os seus trabalhos saiam para a frente. É o carácter da pessoa e o empenho no trabalho, e não a oportunidade de estudar em escolas ou colégios, que contribui à qualidade de trabalho e de vida. Eu tenho aprendido muito de cada um de vocês, não só sobre o seu trabalho, mas também sobre as suas vidas . e o resultado v tem sido o enriquecimento da minha própria vida. Reconheço que a minha contribuição tem sido limitada (em grande parte em função do imperativo teórico e acadêmico), e que estou levando comigo muito mais do que consegui deixar para as pessoas que tem me assistido. Essa contradição para mim tem sido o aspecto mais difícil desse duro e longe processo. Então de uma forma humilde, mas da forma mais sincera, eu gostaria de agradecer-lhes a cada um de vocês pelo tanto que tenham feito e agüentado para o único motivo de me ajudar. Por isso, estou eternamente grata, e em função disso estou dedicando o meu trabalho de doutorado a vocês. ACKNOWLEDGEMENTS There are many individuals and institutions who contributed selflessly to assist in the successful completion of this research. I would first like to thank the Wenner Gren Foundation for Anthropological Research, the National Science Foundation and Health Valley Association for their generous financial support, without which this research would not have been possible. Secondly, I would like to express my profound gratitude to the Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) and the Fundação Vitória Amazônica (FVA) for providing institutional support for fieldwork. I am also indebted to a number of professors and mentors (direct and indirect) to whom I owe much gratitude for inspiring the conceptual framework guiding this research: Ted Gragson (committee Chair), Pete Brosius, Ben Blount, Larry West, Ron Carroll and Frank Golley (committee members), Michael Heckenberger, Eduardo Neves, Jim Petersen, Bill Woods, Nigel Smith, William Denevan, William Sombroek, Ítalo Falesi and Dirse Kern (Black Earth scholars). I would like to give a special thanks to Dr. Manoel Cravo – Brazilian mentor, colleague and friend. Thank you for believing in me and in my ideas enough to take on this project despite the attention and work it would require, and despite the need to go on a bit of intuition and blind faith due to initial barriers of language, discipline and logistics. Thank you for your expansive intellect and warm character, and for the door you opened to intellectual and personal discovery in terra Brazileira. vii I would like to thank Muriel Saragoussi, Elisa Wandelli, Henrique Pereira, Marcos Pinheiro and your families for your friendship and assistance in making this project a reality . for your efforts to decipher meaning out of preliminary letters in a broken tongue, for introducing me to researchers, regional cuisine and warm hospitality, and for your very generous logistical and moral support as I sought to carve out niches for myself in urban and rural Amazonia. I will always remember your kindness and generosity against all effects of time and distance, and would welcome the opportunity to receive you and your families in my home in the future. A number of people in Athens and at the University of Georgia were instrumental in bringing this research to fruition. The office staff at the Department of Anthropology provided much-needed assistance during preliminary stages of my graduate studies, proposal writing, comprehensive exams and fieldwork. Many thanks to all of you. Special thanks to Charlotte Blume, who has a very special ability to create beauty in the world around her, and who is a most deserving anthropologist in her own right for her most profound understanding of the human spirit and of that which nourishes it.