Dirse Clara Kern

Geochemical signatures of tropical soils with archaeological black earth in the Amazon, Brazil

Abstract The archeological black earth (ABE) in Caxiuana, Amazon, differs from the surrounding (AD) and underlying yellow latosols (YLS) through its black color, texture, abundance of organic matter and presence of archaeological artifacts. The ABE contains higher contents of quartz and lesser kaolinite than the yellow latosols. ABE exhibits a P–Mg–Ca–Sr–Ba–Cl–Mn–Zn–Cu geochemical signature, with anomalously low As. This signature can be related to anthropogenic activity. The YLS is characterized by the Fe–Ga–V–Cr–Pb–Nb–Zr–Sc–Cd–Co association which was not modified by the formation of ABE soil, although they were leached during hydromorphic soil formation in the southern part of the ABE exposures. Elements such Y, B and F show no variations throughout the entire area (including ABE and YLS).

The ceramic artifacts in archaeological black earth (terra preta) from lower Amazon region, Brazil: mineralogy

Sitios arqueologicos com Terra Preta, denominados de Terra Preta de Indio ou ainda Terra Preta Arqueologica (TPA) sao muito frequentes na Amazonia. As TPA geralmente contem fragmentos de vasos cerâmicos, por vezes abundantes, alem de liticos, que sao materiais de grande importância para os estudos arqueologicos. Para consubstanciar esses estudos, realizou-se pesquisas mineralogicas e quimicas em fragmentos cerâmicos provenientes de dois sitios arqueologicos da regiao de Cachoeira-Porteira, Estado do Para. Os fragmentos foram classificados segundo seus principais temperos em: cauixi, cariape, areia+feldspatos e caco de vaso cerâmico. Mineralogicamente sao compostos de quartzo, minerais de argila calcinados (especialmente caulinita), feldspatos (albita e microclinio), hematita, goethita, maghemita, variscita-estrengita, fosfatos amorfos, anatasio, e raramente apatita, rhabdophana e oxidos de Mn e Ba. Cauixi e cariape sao componentes orgânicos silicosos e amorfos a DRX. A composicao mineralogica e a morfologia dos seus graos indicam saprolito (material argiloso rico em quartzo) derivado de rochas igneas felsicas de granulacao fina ou rochas sedimentares ricas em argilominerais como materia-prima dos vasos cerâmicos. Neste material argiloso cauixi, cariape e/ou areias, ricas em silica, foram intencionalmente adicionados. O elevado conteudo de fosfatos de Al-Fe, amorfos ou como de baixa cristalinidade, originou-se a partir do contato entre a matriz argilosa da parede do vaso cerâmico com a solucao aquosa quente durante o cozimento diario de alimentos de origem animal (principal fonte de fosforo). A cristalizacao dos fosfatos deve ter prosseguida mesmo depois que os vasos foram descartados, e juntos com os restos de materia orgânica vegetal e animal incorporaram-se aos solos residuais. Participaram desta forma na formacao dos solos tipo TPA.

Geophagy as a Correlate of Folivory in Red-Handed Howler Monkeys (Alouatta belzebul) from Eastern Brazilian Amazonia

Howler monkeys, Alouatta spp., are the most folivorous of neotropical primates (Platyrrhini), although Amazonian red-handed howlers (Alouatta belzebul) are relatively frugivorous. The feeding ecology of a free-ranging group of A. belzebul was monitored at a site in eastern Brazilian Amazonia over a ten-month period (November 1997 to August 1998). The first half of the study period encompassed the peak of the wet season, during which the study groups diet was predominantly frugivorous (scan sample records: 53.5% fruit, 40.8% leaves), and the second half, the transition from wet to dry season, characterized by a marked shift to folivory (18.9% fruit, 77.9% leaves). This shift was accompanied by a marked increase in mature, as opposed to flush leaves, which are relatively rich in secondary compounds. Ingestion of soil from termitaria was recorded on a total of 26 occasions, all of which occurred during the second half of the study period. Soil from termitaria was relatively rich in elements such as Ca and Na and in organic carbon, in comparison with that from the forest floor. The extent to which the monkeys ingested soil for their mineral supplements, or as an aid for the digestion of leaves, in particular the absorption of secondary compounds, remains unclear. The marked correlation with the observed patterns of folivory suggests that the latter function may have been the primary motive for geophagy in this species.

The ceramic artifacts in archaeological black earth (terra preta) from Lower Amazon Region, Brazil: chemistry and geochemical evolution

This paper carried out a chemical investigation of archaeological ceramic artifacts found in archaeological sites with Black Earth (ABE) in the Lower Amazon Region at Cachoeira-Porteira, State of Para, Brazil. The ceramic artifacts, mostly of daily use, belong to Konduri culture (from 900 to 400 years BP). They are constituted of SiO2, Al2O3, Fe2O3, Na2O and P2O5; SiO2 and Al2O3 together add up to 80 % and indicate influence of acid rocks, transformed into clay minerals basically kaolinite. The relative high contents of P2O5 (2.37 % in average) come out as (Al,Fe)-phosphate, an uncommon fact in primitive red ceramics, but found in some roman and egyptian archaeological sites. The contents of the trace elements are similar or below the Earths crust average. This chemical composition (except P2O5) detaches saprolite material derived acid igneous rocks or sedimentary ones as the main raw material of the ceramics. The contents of K, Na and Ca represent the feldspars and rock fragments possibly introduced into saprolitic groundmass, indicated by mineralogical studies. The presence of cauixi and cariape as well as quartz sand was confirmed by optical microscope, SEM analyses and by the high silica contents of ceramic fragments. Phosphorus was possibly incorporated into groundmass during cooking of foods, and ABE soil profile formation developed on yellow Latosols. The raw materials and its tempers (cauixi, or cariape, feldspar, crushed rocks, old ceramic artifacts and quartz fragments) are found close to the sites and therefore and certainly came from them.

Evolution of the Scientific Knowledge Regarding Archaeological Black Earths of Amazonia

In Amazonia many small areas occur where soils were significantly affected by prehistoric man. These soils have a dark color, remains of archaeological materials, and higher Ca, Mg, Zn, Mn, P, and C contents in comparison with the adjacent soils. Known as archaeological black earth (ABE), Indian Black Earth, or terra preta (Kern and Kampf 1989), these soils represent a remarkable example of how man can modify the original soil characteristics in a positive sense, improving its fertility. For this reason, they are frequently sought by the local people for subsistence cultivation of manioc, banana, maize, papaya, etc.

Nutrients in Amazonian Black Earth from Caxiuanã Region

Dispersion of nutrients in Amazonian black earth (ABE) can provide information on human activities of the inhabitants of the Amazon region. Studies on the pH, available phosphorus (P), organic matter (OM) and the exchangeable cations Ca2 + and Mg2 + were performed on soil samples from horizons A1 and A2 over an area with TPA (north-south and east-west) at a site called Ilha de Terra, located in the Conservation Unit Caxiuana National Forest, Melgaco County, Brazil. The results indicated that the OM and Ca2+ are the ones with greater dispersion. Higher correlations were found between OM-Ca-Mg to near the central area. This leads to the inference that the dispersion geochemistry of MO, Ca, Mg and P in archaeological sites with TPA is related to past human activities.

Distribution and availability of copper, iron, manganese and zinc in the archaeological black earth profile from the Amazon region

Os solos de terra preta arqueologica sao ricos em materia orgânica, contem fragmentos cerâmicos e artefatos liticos e apresentam nutrientes em concentracoes mais elevadas do que outros tipos de solos. Com o intuito de contribuir com informacoes sobre concentracoes de micronutrientes disponiveis em solos de terra preta, foram avaliadas atraves de extracoes quimicas sequenciais, a distribuicao e disponibilidade de Cu, Fe, Mn e Zn em um perfil de terra preta arqueologica no municipio de Juruti, estado do Para. As maiores concentracoes de Cu, Fe, Mn e Zn no perfil sao encontradas na fracao residual. Este estudo mostrou que ferro, manganes e zinco sao preferencialmente disponiveis a partir das fracoes, associados aos oxidos de Fe-Mn, variando de 1265,39 a 1818,12 mg kg-1, 0,83 a 48,51 mg kg-1 e 1,92 a 12,05 mg kg-1, respectivamente, e o cobre a partir da materia orgânica, variando de 0,13 a 0,45 mg kg-1.

Comportamento do mercúrio em perfis de solos do sítio Ilha de Terra-Caxiuanã, Pará

Behavior of mercury in soil profiles with archaeological black earth (ABE) and surroundings area (SA) from Sitio Ilha de Terra, Caxiuana, can provide information on anthropogenic activity of the Amazonian habitat. The samples of ABE and SA soil profiles were submitted to mineralogical chemical (total and sequential) analysis. The data show that the Hg occurs mainly in goethite and kaolinite in the two soil profiles. The highest concentrations of Hg and Fe are observed in the SA profile. These results indicate that the prehistoric human occupation contributed to the decrease of the concentration of Hg in soil ABE from Caxiuana.

Mineralogia e geoquímica de perfis de solo com Terra Preta Arqueológica de Bom Jesus do Tocantins, sudeste da Amazônia

A comparacao de dados morfologicos, mineralogicos e quimicos de solo com horizontes antropicos - Terra Preta Arqueologica (TPA) com Argissolos adjacentes permitiu identificar os principais processos responsaveis pela formacao da TPA em um sitio arqueologico no Municipio de Bom Jesus do Tocantins, sudeste do Estado do Para. A similaridade entre os dados dos horizontes subsuperficiais do solo com TPA e solos adjacentes indica que o horizonte antropico do solo TPA foi provavelmente desenvolvido a partir de um horizonte similar aos Argissolos adjacentes com posterior transformacao pedogenetica atraves da introducao de materiais orgânicos e inorgânicos por antigas colonizacoes humanas, resultando no espessamento do horizonte superficial e em concentracoes maiores de CaO e P2O5 (teores totais), Zn (teor traco), P e Zn disponivel (teores disponiveis), alem de Ca e Mg trocaveis (teores trocaveis) em relacao aos Argissolos adjacentes. Alem disso, essa intervencao antropica antiga tambem provocou modificacoes no horizonte subsuperficial do Argissolo com TPA, como concentracoes altas de P2O5 e principalmente P disponivel. O Soil Taxonomy e o Sistema Brasileiro de Classificacao de Solos (SiBCS) sao adequados para a identificacao de solo com horizonte antropico (p.exe. TPA), uma vez que priorizam nas ordens do solo os principais processos pedogeneticos atuantes na formacao do solo, relacionados aos horizontes subsuperficiais, alem das transformacoes pedogeneticas posteriores no horizonte superficial. Contudo, este trabalho recomenda o acrescimo de alguns atributos diagnosticos como quantidade de artefatos cerâmicos e liticos, P2O5, P e Zn disponiveis, C orgânico, Ca2++ Mg2+ (teores trocaveis), CTC e indice de saturacao por bases no horizonte superficial para o agrupamento e distincao dos diversos tipos de solos antropicos antigos da Amazonia.

Organic Matter in Archaeological Black Earths and Yellow Latosol in the Caxivanã, Amazonia, Brazil

The National Reserve of Caxivana, located in the Lower Amazon region, is a place where environmental preservation is still possible even though its surroundings are densely inhabited. The Ferreira Penna Scientific Station (ECFPn) is a building in the reserve and belongs to the Museu Paraense Emilio Goeldi (MPEG), supporting multidisciplinary research in terms of species, communities, and ecosystems.