Talks by Brancier Jeanne
Nos últimos anos, as pesquisas nas regiões central e oeste da Amazônia confirmam que as antigas o... more Nos últimos anos, as pesquisas nas regiões central e oeste da Amazônia confirmam que as antigas ocupações humanas tiveram um impacto no meio ambiente da região, incluindo a paisagem, os solos e a floresta. A partir dessas evidências, o projeto de pesquisa " LongTIme " foi iniciado na Guiana francesa com a finalidade de preencher a lacuna de informação existente na Amazónia oriental. Ao reunir pesquisadores das ciências humanas (arqueólogos, etnólogos) e das ciências ambientais (ecólogos, pedólogos), com colaboradores indígenas, esse projeto interdisciplinar se dedica a entender como as antigas populações influenciaram a biodiversidade florestal. A área de estudo se expande sobre uma ampla área (150Ha), no baixo igarapé Arataïe, e inclui vegetações diversas, como bambuzais, e um sitio arqueológico típico da Guiana, chamado Montagnes couronnées. Esses sítios se encontram no topo de colinas na floresta e são rodeados por um fosso antrópico que indicam ocupações massivas. Como são de difícil aceso, poucas escavações foram feitas até o momento e ainda pouco compreendemos sobre suas funções. Assim, a parte geoarqueológica de LongTIme se inspira nos estudos sobre as Terras Pretas brasileiras, utilizando a micromorfólogia com análises geoquímicas para definir os solos antrópicos da Guiana. Os primeiros resultados micromorfológicos destacam índices de atividades de desmatamento para abrir zonas na floresta (instalação de áreas residenciais ou agrícolas), de combustão (sistemas de corte e queima e/ou fogões) e de limpeza dos solos (gestão de lixo), o que nos permite localizar algumas dessas atividades na paisagem do igarapé Arataïe e iniciar uma reflexão sobre os usos do lugar. Estudos geoquímicos em curso propiciarão informações complementares quando os solos arqueológicos estudados possuíem um enriquecimento relativo em relação aos solos naturais. Em suma, esse estudo tem como objetivo secundário comparar os solos arqueológicos da Guiana com os arqueoantrossolos da Amazônia.
French Guiana belongs to the northern part of the Amazonian region, which is characterized by the... more French Guiana belongs to the northern part of the Amazonian region, which is characterized by the presence of large areas covered by generally infertile soils such as Ferralsols (Oxisols). In the Amazon part of Brazil, thanks to archaeological research, fertile Anthrosols of pre-Columbian origin were found including terra preta and terra mulata. These Amazonian Dark Earth (ADE) or Brazilian Dark Earth (BDE) are characterized by past occupations remains like potteries or charcoals, and by high amounts of charred organic matter and nutrient stocks. Terra preta is most often considered to be associated with important settlements in pre-Columbian Amazonia, while terra mulata might be the sign of intensive landscape domestication around living place. The formation of ADE/BDE is thought to take place between the first millennium BC and first millenium AD. In French Guiana pre-Columbian Anthrosols have been found in different geomorphological contexts and for different cultural periods. Up to now, they have not been studied in a geoarchaeological way and the question of "their belonging" to the Amazonian Dark Earth is still asked. It is hypothesized that Guianan Dark Earth (GDE) could contain high amounts of nutrient like Amazonian/Brazilian Dark Earth, but no study has focused on this question yet. In order to characterized GDE, geochemical analysis were performed on Anthrosols coming from two sites from alluvial context (lower Holocene terrace of the Maroni River, Saint-Laurent-du-Maroni region), and two ring-ditch sites from lateritic hills under rainforest (watershed of the Approuague River, Regina region). Geochemical analyses were chosen following the literature about ADE including available and total P, Ca, N, Mg, K, Zn, Mn and CEC. In ADE these nutrients are generally found in higher amount than in surrounding soils.
Recent archaeological research in French Guiana conducted by INRAP (Institut National de Recherch... more Recent archaeological research in French Guiana conducted by INRAP (Institut National de Recherches Archéologiques Préventives), specifically in the Couac Program (Cirad, Inra, Inrap) revealed precolombian settlements on different geomorphic contexts like coastal and fluvial areas, as is seen in Brazil, but also what seems to be quite a dense occupation on higher grounds (mounds). Most of the times, the excavation shows cultural remains like pottery, archaeological pits and ditches, as well as sediments that are described by the archaeologists as “thick and dark-coloured layers”. In Brazil, dark layers found in archaeological sites are called Terra Preta do Indio or Amazonian Dark Earth (ADE), and their study is thought necessary to explain and understand ancient human settlement. In Brazil, geoarchaeological methods as well as chemical analyses, pedology and micromorphology helped to describe ADE and understand their archaeological potential and characteristics. In order to better understand the French Guiana dark layers, we studied two sites from the estuarine zone of the lower Maroni River (Surinam border) (Chemin Saint Louis and Balaté at Saint Laurent du Maroni), and two ring-ditched hilltop sites, on ferralsols, in the interfluvial forest area (“Montagnes Couronnées” in French) (MC 87 et 88, near Regina). Regarding Brazilians research on ADE, we described for the first time the archaeological stratigraphy of French Guiana ancient settlement using a geoarchaeological approach combining biogeochemistry, pedology in correlation with micromorphological analyses. Our first results show that dark layers from archaeological sites studied are very different from natural soils underneath in the estuarine zone. Although, the pH is quite low, micromorphological analyses show clay coatings in the alluvial terrace before human settlement.
These analyses also show more organic matter and charcoals in the archaeological layers than beneath, and very large amounts of phytolithes, that give to botanists a new way of research. Due to either the acid context and / or to the ancient lifestyle, very few bones were found. We also found geochemical and micromorphological differences between the sites in the estuarine zone or in forest area. First geoarchaeological results give information about the nature of the sites, and suggest that French Guiana dark layers have original properties. We therefore suggest, in accordance with the archaeologist team, to call them Guianan Dark Earth (GDE). If we compare the GDE of this study with data from bibliographic review on ADE, micromorphological analyses show that GDE presents less anthropogenic components than ADE. Chemical analyses also show differences between GDE and ADE, like pH and available nutrients, lower in estuarine GDE. These differences suggested that GDE can have different properties than those of ADE, but are nonetheless part of the archaeological soils of the Amazonian basin.
Posters by Brancier Jeanne
Papers by Brancier Jeanne
Recent archaeological research in French Guiana conducted by INRAP (Institut National de Recherch... more Recent archaeological research in French Guiana conducted by INRAP (Institut National de Recherches Archéologiques Préventives), specifically in the Couac Program (Cirad, Inra, Inrap) revealed precolombian settlements on different geomorphic contexts like coastal and fluvial areas, as is seen in Brazil, but also what seems to be quite a dense occupation on higher grounds (mounds). Most of the times, the excavation shows cultural remains like pottery, archaeological pits and ditches, as well as sediments that are described by the archaeologists as "thick and dark-coloured layers". In Brazil, dark layers found in archaeological sites are called Terra Preta do Indio or Amazonian Dark Earth (ADE), and their study is thought necessary to explain and understand ancient human settlement. In Brazil, geoarchaeological methods as well as chemical analyses, pedology and micromorphology helped to describe ADE and understand their archaeological potential and characteristics. In order ...
Les recherches entreprises dans cette these visent a definir les processus de formation des anthr... more Les recherches entreprises dans cette these visent a definir les processus de formation des anthroposols archeologiques precolombiens sur le territoire guyanais ainsi qu'a participer a la restitution des activites humaines passees. Elles sont fondees sur l'etude et l'analyse des proprietes intrinseques des sediments archeologiques, telles que, d'une part, leur nature et leur organisation pedo-sedimentaires, et d'autre part, leurs proprietes physico-chimiques. La possibilite de disposer d'un corpus de sites archeologiques de plein air dans differents contextes geomorphologiques (plaine alluviale, colline lateritique pour les montagnes couronnees), et la mise en place d'une approche geoarcheologique combinant observations micromorphologiques et analyses physico-chimiques, a permis d'investiguer differents types d'anthroposols precolombiens guyanais, et de les caracteriser suivant plusieurs marqueurs anthropiques, directs et indirects. L'analyse ...
Géomorphologie : relief, processus, environnement
Par ses activités, l’homme a contribué, par le passé, à transformer les sols dans une telle mesur... more Par ses activités, l’homme a contribué, par le passé, à transformer les sols dans une telle mesure que les référentiels pédologiques internationaux consacrent une classe aux anthroposols archéologiques. Dans les Antilles-Guyane, les travaux des 20 dernières années en archéologie préventive ont mis au jour des anthroposols archéologiques en contextes précolombiens. Les questionnements archéologiques portent sur l’origine de ces sols sombres, épais et d’aspect homogène, et les modes d’occupations passés qu’ils expriment. Afin de répondre à ces questionnements, la micromorphologie apparaît comme un outil efficace pour déterminer les processus de formation des sols, tant pédologiques qu’archéologiques, tout en informant sur les activités humaines anciennes. L’analyse comparative de deux anthroposols archéologiques martiniquais et guyanais vise à dégager les caractères communs et les spécificités stationnelles ou culturelles. Les résultats de cette étude montrent que : (i) les indicateurs microscopiques d’anthropisation des sols élaborés sur cinq sites archéologiques guyanais sont transposables à l’anthroposol martiniquais étudié ; (ii) les anthroposols analysés se sont mis en place par des apports rythmés (anthroposols cumuliques). Selon les indicateurs, les variations intra-site de l’anthroposol guyanais témoignent d’aires d’activité différentes, tandis que le site martiniquais correspond à une zone d’occupation peu intense. Ces résultats montrent également qu’en termes de processus, les sols précolombiens des Antilles-Guyane correspondent à des anthroposols archéologiques alors qu’ils sont exclus, pour certains, du référentiel pédologique français, du fait de leur trop faible épaisseur et/ou abondance en composants anthropiques. Ceci conduit à proposer une révision de leur définition dans les référentiels pédologiques, afin de les inclure.
Zeitschrift für Geomorphologie, Supplementary Issues, 2014
In order to document site formation processes at microscale and to characterise pre-Columbian Fre... more In order to document site formation processes at microscale and to characterise pre-Columbian French Guiana dark soils (FGDS), micromorphology was performed on three sites. For the first time it was possible (i) to microscopically characterise pre-Columbian Anthrosols in different physical contexts and (ii), to identify anthropogenic features associated with past human occupation. Microfeatures of the Holocene alluvial terrace of the lower Maroni River witnessed (i) several episodes of clay enrichment and/or redistribution, (ii) seasonal waterlogging, and (iii), post-depositional biological activity. Clay enrichment and organic matter inputs together with biological activity processes might have alternated, probably in relation to vegetal cover and/or anthropogenic activities. On top of the alluvial terrace, bioturbated dark layers are enriched in fine brown organic matter and charcoals. Cumulic soil development was favoured when successive sediment inputs due to episodic flooding and/or overland flow was possible (Chemin Saint Louis site). On a lateritic hill, under rainforest, at the MC87 ring-ditched mountain (Montagnes Couronnées or Crowned Mountain), microscale identification of yellowish unburnt oxic B horizon aggregates together with anthropogenic features related to fire such as charcoals and burnt soil fragments (rubefied and dark brown aggregates) stress that lateritic soil acted as support for activities in the enclosure, and as reworked material in the ditch. These components could result from clearance for settlement, agricultural management and cultivation, or domestic activities. The obtained results allow first comparisons to be drawn between pre-Columbian FGDS and Brazilian dark earths (BDE). Except a similarity in colour, the former is revealed to be less rich in anthropogenic components with an absence of phosphatic elements such as bones.
Zeitschrift Fur Geomorphologie Supplementary Issues, Feb 1, 2014
In order to document site formation processes at microscale and to characterise pre-Columbian Fre... more In order to document site formation processes at microscale and to characterise pre-Columbian French Guiana dark soils (FGDS), micromorphology was performed on three sites. For the first time it was possible (i) to microscopically characterise pre-Columbian Anthrosols in different physical contexts and (ii), to identify anthropogenic features associated with past human occupation. Microfeatures of the Holocene alluvial terrace of the lower Maroni River witnessed (i) several episodes of clay enrichment and/or redistribution, (ii) seasonal waterlogging, and (iii), post-depositional biological activity. Clay enrichment and organic matter inputs together with biological activity processes might have alternated, probably in relation to vegetal cover and/or anthropogenic activities. On top of the alluvial terrace, bioturbated dark layers are enriched in fine brown organic matter and charcoals. Cumulic soil development was favoured when successive sediment inputs due to episodic flooding and/or overland flow was possible (Chemin Saint Louis site). On a lateritic hill, under rainforest, at the MC87 ring-ditched mountain (Montagnes Couronnées or Crowned Mountain), microscale identification of yellowish unburnt oxic B horizon aggregates together with anthropogenic features related to fire such as charcoals and burnt soil fragments (rubefied and dark brown aggregates) stress that lateritic soil acted as support for activities in the enclosure, and as reworked material in the ditch. These components could result from clearance for settlement, agricultural management and cultivation, or domestic activities. The obtained results allow first comparisons to be drawn between pre-Columbian FGDS and Brazilian dark earths (BDE). Except a similarity in colour, the former is revealed to be less rich in anthropogenic components with an absence of phosphatic elements such as bones.
In order to document site formation processes at microscale and to characterise pre-Columbian Fre... more In order to document site formation processes at microscale and to characterise pre-Columbian French Guiana dark soils (FGDS), micromorphology was performed on three sites. For the first time it was possible (i) to microscopically characterise pre-Columbian Anthrosols in different physical contexts and (ii), to identify anthropogenic features associated with past human occupation. Microfeatures of the Holocene alluvial terrace of the lower Maroni River witnessed (i) several episodes of clay enrichment and/or redistribution, (ii) seasonal waterlogging, and (iii), post-depositional biological activity. Clay enrichment and organic matter inputs together with biological activity processes might have alternated, probably in relation to vegetal cover and/or anthropogenic activities. On top of the alluvial terrace, bioturbated dark layers are enriched in fine brown organic matter and charcoals. Cumulic soil development was favoured when successive sediment inputs due to episodic flooding and/or overland flow was possible (Chemin Saint Louis site). On a lateritic hill, under rainforest, at the MC87 ring-ditched mountain (Montagnes Couronnées or Crowned Mountain), microscale identification of yellowish unburnt oxic B horizon aggregates together with anthropogenic features related to fire such as charcoals and burnt soil fragments (rubefied and dark brown aggregates) stress that lateritic soil acted as support for activities in the enclosure, and as reworked material in the ditch. These components could result from clearance for settlement, agricultural management and cultivation, or domestic activities. The obtained results allow first comparisons to be drawn between pre-Columbian FGDS and Brazilian dark earths (BDE). Except a similarity in colour, the former is revealed to be less rich in anthropogenic components with an absence of phosphatic elements such as bones.
Thesis Chapters by Brancier Jeanne
The research undertaken in this thesis, aims to identify the formation processes of the pre-Colum... more The research undertaken in this thesis, aims to identify the formation processes of the pre-Columbian archaeological anthropogenic soils in the French Guiana territory as well as to contribute to revisiting ancient human activities. It is based on the study and analysis of the intrinsic properties of archaeological sediments, such as, on the one hand, their nature and their pedo-sedimentary composition, and on the other hand, their physicochemical properties. The availability of a corpus of open air archaeological sites in different geomorphological settings (e.g., floodplain; lateritic hill with circular ditch glossed in French montagne couronnée), and the implementation of a geoarchaeological approach combining micromorphological observations and physicochemical analyses, enabled to investigate different kinds of pre-Columbian anthropogenic soils in French Guiana, and to characterize them according to several anthropogenic markers, both direct and indirect. Geoarchaeological analysis revealed that the natural pedogenesis has been impacted by the ancient anthropization and indicates a certain resilience of soils. The soil micromorphology demonstrated anthropogenic microtraces such as charcoal (micro and macro) and fragments of pottery, common to both contexts, as well as different kinds of heated aggregates originating from the surface of the soils having been burned, only for the montagnes couronnées sites. Anthropogenic activity probably also contributed to the process of leaching of clay via the formed ashes. The pedofaune has been transformed as one may assume, in thin sections, the presence of pedofeatures related to Pontoscolex corethrurus. Additional archaeo-environmental analyses implemented in this study (anthracology, phytoliths, magnetic susceptibility) allowed completing the data acquired on the implementation of the studied anthropogenic soils. These studies, pioneering for French Guiana, though inspired by studies in the near Brazilian Amazon on terra preta/mulata or Amazonian Dark Earth, complement the repository of archaeological anthropogenic soils developed in the Amazon. Furthermore, they allowed several hypotheses about the origins of the activity markers, either direct or indirect, observed in the archaeological anthropogenic soils, and evidenced ancient human events that could have taken place on the sites studied. Fundamental activities such as house fires or the cultivation of the land appear to have taken place on the latter. Assumptions about the models of occupation of space have been proposed mainly by refuse areas behind the supposed houses and near the ditch in the case of the montagnes couronnées. This study is situated in an archaeo-environmental approach demonstrating the close relations between pre-Columbian populations with their environment.
Les recherches entreprises dans cette thèse visent à définir les processus de formation des anthr... more Les recherches entreprises dans cette thèse visent à définir les processus de formation des anthroposols archéologiques précolombiens sur le territoire guyanais ainsi qu’à participer à la restitution des activités humaines passées. Elles sont fondées sur l’étude et l’analyse des propriétés intrinsèques des sédiments archéologiques, telles que, d’une part, leur nature et leur organisation pédo-sédimentaires, et d’autre part, leurs propriétés physico-chimiques. La possibilité de disposer d’un corpus de sites archéologiques de plein air dans différents contextes géomorphologiques (plaine alluviale, colline latéritique pour les montagnes couronnées), et la mise en place d’une approche géoarchéologique combinant observations micromorphologiques et analyses physico-chimiques, a permis d’investiguer différents types d’anthroposols précolombiens guyanais, et de les caractériser suivant plusieurs marqueurs anthropiques, directs et indirects. L’analyse géoarchéologique révèle que la pédogénèse naturelle a été impactée par l’anthropisation ancienne et indique une certaine résilience des sols. La micromorphologie des sols a permis de mettre en évidence des microtraces anthropiques telles que des charbons (micro et macro) et des céramiques, communs aux deux contextes, ainsi que différents types d’agrégats brûlés provenant de la surface des sols ayant subi la chauffe pour les montagnes couronnées. L’activité anthropique a aussi probablement favorisé les processus de lessivage des argiles par des apports anciens de cendres. La pédofaune a été transformée comme le laisse supposer, en lames minces, la présence de traits rapportés à Pontoscolex corethrurus. Les analyses archéo-environnementales complémentaires mises en place dans ce travail (anthracologie, phytolithes, susceptibilité magnétique) ont permis de compléter les données acquises sur la mise en place des anthroposols étudiés. Ces travaux, précurseurs pour le territoire guyanais, et en s’inspirant des études menées non loin, en Amazonie brésilienne sur les terra preta/mulata ou Amazonian Dark Earth, viennent compléter le référentiel des anthroposols archéologiques développés en Amazonie. Ils ont, en outre, permis d’émettre plusieurs hypothèses quant à l’origine des marqueurs d’activités, directs ou indirects, observés dans les anthroposols archéologiques, et de mettre ainsi en évidence les manifestations humaines anciennes qui auraient pu avoir lieu sur les sites étudiés. Des activités fondamentales telles que les foyers domestiques ou la mise en culture des sols semblent avoir pris place sur ces derniers. Des hypothèses sur les modèles d’occupation de l’espace ont été proposées en s’intéressant aux zones de rejet principalement, situées en retrait des maisons supposées et à proximité du fossé dans le cas des montagnes couronnées. Cette étude s’inscrit typiquement dans une approche archéo-environnementale qui vient préciser les liens étroits qu’entretenaient les populations précolombiennes avec leur environnement.
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Talks by Brancier Jeanne
These analyses also show more organic matter and charcoals in the archaeological layers than beneath, and very large amounts of phytolithes, that give to botanists a new way of research. Due to either the acid context and / or to the ancient lifestyle, very few bones were found. We also found geochemical and micromorphological differences between the sites in the estuarine zone or in forest area. First geoarchaeological results give information about the nature of the sites, and suggest that French Guiana dark layers have original properties. We therefore suggest, in accordance with the archaeologist team, to call them Guianan Dark Earth (GDE). If we compare the GDE of this study with data from bibliographic review on ADE, micromorphological analyses show that GDE presents less anthropogenic components than ADE. Chemical analyses also show differences between GDE and ADE, like pH and available nutrients, lower in estuarine GDE. These differences suggested that GDE can have different properties than those of ADE, but are nonetheless part of the archaeological soils of the Amazonian basin.
Posters by Brancier Jeanne
Papers by Brancier Jeanne
Thesis Chapters by Brancier Jeanne
These analyses also show more organic matter and charcoals in the archaeological layers than beneath, and very large amounts of phytolithes, that give to botanists a new way of research. Due to either the acid context and / or to the ancient lifestyle, very few bones were found. We also found geochemical and micromorphological differences between the sites in the estuarine zone or in forest area. First geoarchaeological results give information about the nature of the sites, and suggest that French Guiana dark layers have original properties. We therefore suggest, in accordance with the archaeologist team, to call them Guianan Dark Earth (GDE). If we compare the GDE of this study with data from bibliographic review on ADE, micromorphological analyses show that GDE presents less anthropogenic components than ADE. Chemical analyses also show differences between GDE and ADE, like pH and available nutrients, lower in estuarine GDE. These differences suggested that GDE can have different properties than those of ADE, but are nonetheless part of the archaeological soils of the Amazonian basin.