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Studies on Terra Preta
Document in PDF (3,6 Mo)
- Earthmovers of the Amazon
Document in PDF (436 ko)
- Amazonian dark earths as carbon stores and sinks
Document in PDF (205 ko)
- Terra Preta soils and their archaeological context in the caqueta basin of southeast Colombia.
Document in PDF (132 ko)
- Historical ecology and future explorations.
Document in PDF (1,4 Mo)
- The long term memory of soils: How Amazonian dark earths refect past land use.
Document in PDF (455 ko)
- Pedogenesis and pre-Colombian land use of Terra Preta Anthrosols.
Document in PDF (975 ko)
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Abstract: Several archaeological black earth (ABE) sites occur in the Amazon region. They contain fragments of ceramic artifacts, which are very important for the archaeological purpose. In order to improve the archaeological studyin the region we carried out a detailed mineralogical and chemical study of the fragments of ceramic artifacts found in the two ABE sites of Cachoeira-Porteira, in the Lower Amazon Region. Their ceramics comprise the following tempers: cauixi, cariapé, sand, sand +feldspars, crushed ceramic and so on and are composed of quartz, clay equivalent material (mainly burned kaolinite), feldspars, hematite, goethite, maghemite, phosphates, anatase, and minerals of Mn and Ba. Cauixi and cariapé, siliceous organic compounds, were found too. The mineralogical composition and the morphology of their grains indicate a saprolite (clayey material rich on quartz) derived from fine-grained felsic igneous rocks or sedimentary rocks as source material for ceramic artifacts, where silica-rich components such cauixi, cariapé and/or sand (feldspar and rock fragments) were intentionally added to them. The high content of (Al,Fe)-phosphates, amorphous to low crystalline, must be product of the contact between the clayey matrix of pottery wall and the hot aqueous solution formed during the daily cooking of animal foods (main source of phosphor). The phosphate crystallization took place during the discharge of the potteries put together with waste of organic material from animal and vegetal origin, and leaving to the formation of the ABE-soil profile.
Journal Title: Acta Amazonica (Acta Amazon.) 2004, vol. 34, no2, pp. 165-178.
Abstract: For more than 30 years, archaeologists have clashed over whether the vast Bolivian river basin called the Beni could provide the resources for indigenous cultures to grow beyond small, autonomous villages. Now a small but growing number of researchers believe that the region was once home to cultures fully as sophisticated as the better known, though radically different, cultures of the Aztecs, Incas, and Mayas. Although these still unnamed peoples abandoned their earthworks between 1400 and 1700 C.E., researchers say, they permanently transformed regional ecosystems--a notion with dramatic implications for conservation.
Source : Science Magazine .4 February 2000, VOL 287, pp. 786 - 789
Abstract: Investigation of dark earths from two archaeological sites near Araracuara, on the Rio Caqueta in Colombian Amazonas, indicates that these soils are anthropic, with characteristics similar to those of the terra preta soils of the Brazilian Amazon. The Araracuara sites belong to the Camani (plainware) phase of the second to ninth centuries A.D. and to the Nofueri phase (ninth to seventeenth centuries) with pottery of the Polychrome Tradition. The Araracuara examples are the first archaeological terra preta soils analyzed from west of Brazil, although similar materials are reported from Ecuador and Peru. The problems of recognizing and dating the first appearance of terra preta soils are discussed, and a plea is made for closer collaboration between archaeologists and soil scientists.
Source: American Antiquity, 49: 125-14. 1984.
Source: Amazonian Dark Earths: Origins, Properties, Management. Edited by J. Lehmann, D. Kern, B. Glaser, and W. Woods, Kluwer, Dordrecht, pp. 455-500.