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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Anatomia do lenho e do carvão de espécies arbóreas do Cerrado no Estado de São Paulo, Brasil

Gonçalves, Thaís Alves Pereira [UNESP] 27 August 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-27Bitstream added on 2014-06-13T19:29:36Z : No. of bitstreams: 1 goncalves_tap_me_botfca.pdf: 2550368 bytes, checksum: 024d4159f78f351a8b6ce296e16b0311 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A Antracologia é uma ciência que se baseia na anatomia da madeira para realizar a análise e identificação de carvão vegetal. No Brasil, ela visa tradicionalmente obter dados paleoecológicos e paleoetnobotânicos, mas também conservacionistas e tecnológicos. As análises antracológicas são possíveis porque a estrutura do lenho se mantém no carvão, entretanto, variações morfométricas podem ocorrer. O presente estudo visa contribuir para um melhor entendimento do efeito da carbonização no lenho através da análise estrutural da anatomia antes e após carbonização. A escolha de espécies do cerrado deveu-se ao forte impacto que este bioma sofre pela devastação e, principalmente, pelo uso de suas espécies para a produção de carvão vegetal. A anatomia do lenho e do carvão obtido a 400ºC foram analisadas em amostras de Copaifera langsdorffii, Dalbergia violacea, Dimorphandra mollis, Stryphnodendron polyphyllum, Caryocar brasiliense, Couepia grandiflora, Tapirira guianensis, Qualea grandiflora, Vochysia tucanorum e Pouteria torta, todas provenientes do cerrado e apresentando tipos anatômicos distintos. Todos os resultados quantitativos foram comparados estatisticamente. A contração anisotrópica nos carvões foi evidenciada principalmente na redução do diâmetro tangencial dos vasos, que ocorreu em 70% das espécies, mas não foi o suficiente para aumentar significativamente sua frequência; o diâmetro da abertura das pontoações intervasculares praticamente se manteve; a frequência dos raios aumentou ligeiramente; a altura e a largura dos raios variaram bastante, sendo que os raios mais largos contraíram mais que os estreitos; o parênquima axial manteve, no carvão, características semelhantes às do lenho; as fibras dos carvões perderam a distinção das camadas das paredes celulares presentes no lenho, mas mantiveram dimensões semelhantes... / Anthracology, or charcoal analysis, is a science based on wood anatomy. In Brazil it traditionally studies palaeoenvironment and palaeoethnobotany, as well as nature conservancy and forestry technology. Anthracological analyses are possible due to the maintenance of wood structure in charcoal. The present study aims to contribute to a better knowledge of carbonization on wood anatomy. Fresh and charred cerrado woods samples were analyzed. The Brazilian cerrado is highly impacted by devastation, while its species are widely used for charcoal production. The latter were charred under 400ºC. The selected species present different anatomical characteristics: Copaifera langsdorffii, Dalbergia violacea, Dimorphandra mollis, Stryphnodendron polyphyllum, Caryocar brasiliense, Couepia grandiflora, Tapirira guianensis, Qualea grandiflora, Vochysia tucanorum, and Pouteria torta. All the quantitative data between wood and charcoal were statistically analyzed. The anisotropic pattern of contraction in charcoals was evident as 70% of the species presented a reduction in vessels tangential diameter. Vessel frequency increase, however, was not statistically significant. Intervessel pits apertures diameters were very closely between wood and charcoal. Rays frequency slightly increased; rays height and width were extremely variable. Larger rays contract more than narrow ones. Axial parenchyma retained, in charcoal, the same dimensions and shape of wood. Charcoal fibres presented indistinct cell wall layering, but retained similar dimensions of wood fibres. Carbonization under 400ºC caused only few changes between wood and charcoal, corroborating the assumption that wood anatomy and anthracology are two closely related sciences
2

Antrakologie a NMR spektroskopie v paleoekologickém výzkumu černozemí / Anthracology and NMR spectroscopy in Palaeoecological Research of Chernozems

Danková, Lenka January 2012 (has links)
This thesis deals with black carbon, its characteristic features and with its occurrence in chernozemic soils. In particular, this thesis deals with methods, which can study presence of black carbon in soils. The presence of black carbon and the whole composition of soil organic matter of three chernozemic soils in Czechia (Zeměchy, Tursko, Syrovice) is examined by 13 C NMR spectroscopy. Anthracological analysis of charcoal from fossil chernozems of Zemechy loess ravine deals with pedogenesis of chernozems and development of Quaternary vegetation in Central Europe. Coniferous tree species of Pinus sp., Pinus cf. cembra, Larix/Picea, Juniperus a Vaccicium, i.e. cold- and drought-tolerant taxa, were identified by anthracological analysis of soils of Zemechy loess ravine. The identified species suggest that the landscape around Zemechy was probably formed by parkland taiga. According to 13 C NMR spectroscopy, soil organic matter of fossil chernozem of Zemechy loess ravine consists particularly of alkyl and O-alkyl carbon. Aromatic carbon is also significant. O-alkyl carbon is the most important in the recent chernozems of Tursko and Syrovice. Aromatic carbon has the smallest proportion in both chernozems. The presence of aromatic carbon in chernozem of Tursko is the smallest of all analyzed soils. The...
3

Approche expérimentale de la conservation des charbons de bois dans les gisements paléolithiques : processus post-dépositionnels, fragmentation et représentativité des assemblages anthracologiques / Experimental approach of the preservation of charcoals in the palaeolithic deposits : process post--dépositional, fragmentation and representativeness of the anthracological assemblies anthracologiques

Chrzavzez, Julia 05 November 2013 (has links)
Dans les gisements paléolithiques, les résidus anthracologiques étudiables sont parfois très abondants ou, au contraire, quasiment absents, sans relation évidente avec l’intensité des activités liées au feu. Ce constat pose la question de l’impact des processus post-dépositionnels, dont l’action est particulièrement importante dans les sites anciens. Lorsque la fraction grossière est rare, les charbons méso ou microscopiques sont souvent bien représentés, mettant en lumière un intense processus de fragmentation. Agent majeur de la formation des assemblages, la fragmentation conditionne le niveau de conservation du dépôt, mais aussi éventuellement la représentation quantitative des taxons. Dans une perspective méthodologique et au moyen d’une série d’expérimentation in vivo et in vitro (tests de compression, cycles gel-dégel, piétinement, retrait-gonflement du sédiment, etc.), les propriétés physico-mécaniques des charbons de bois et les modalités de fragmentation de différents taxons d’Europe tempérée sont caractérisées. Un ensemble de processus post-dépositionnels qui participent de la formation de nombreux dépôts du Pléistocène sont simulés de manière à mesurer leur impact sur le matériel anthracologique. Nos résultats montrent que les charbons de bois sont particulièrement sensibles aux processus météoriques et aux phénomènes périglaciaires ainsi qu’au piétinement. Le niveau de fragmentation des charbons laisse envisager l’ampleur des dommages causés sur la longue durée. Les propriétés physico-mécaniques et le comportement à la fragmentation des charbons de bois varient selon les essences. Ces différences s’expriment au niveau générique, spécifique et plus ponctuellement intra-spécifique, mais elles ne semblent pas de nature à induire des distorsions quantitatives majeures de la représentation initiale des taxons au sein des assemblages. Enfin, lorsque des différences entre taxons sont mises en évidence, elles s’expriment principalement au sein de la fraction fine (charbons compris entre 1 et 2 mm), laquelle est rarement étudiée en termes quantitatif. / Anthracological residues are often either very abundant or almost entirely absent in Palaeolithic sites, with no obvious relationship between their quantity and in the intensity of fire-related activities that may have occurred. This raises the question of the impact of post-depositional processes on anthracological residues, which is especially significant at ancient sites. When the coarse fraction is rare, meso and microscopic charcoal are often well represented, highlighting an intense process of fragmentation. As a major agent of the assemblages’ formation, fragmentation affects the level of conservation of the deposit, but also possibly the quantitative representation of taxa. From a methodological perspective and through a series of in vivo and in vitro experiments, the physico-mechanical properties of charcoal and the modalities of fragmentation of Europe temperate taxa are characterized. A set of post-depositional processes (freeze-thaw cycles, trampling, sediment shrinking and swelling, etc.), involved in the formation of many Pleistocene deposits, are simulated in order to measure their impact on anthracological residues. The results of this research show that charcoal is particularly sensitive to meteoric and periglacial processes as well as trampling. The level of fragmentation of charcoal makes it possible to consider the scale of damage caused over a long term exposure of the remains. The physico-mechanical properties and the fragmentation behavior of charcoal vary depending on the species. These differences are visible on a generic, specific and intra-specific level, though they do not seem to induce major distortions of the initial quantitative representation of taxa within assemblages. Finally, when differences between taxa are identified, they are mainly recovered in the fine fraction (charcoal between 1 and 2 mm), which is rarely studied in quantitative terms.
4

Recursos forestales en un medio semiárido. Nuevos datos antracológicos para la Región de Murcia desde la Edad del Bronce hasta época medieval

García Martínez, María Soledad 23 July 2009 (has links)
Esta tesis doctoral recoge el estudio antracológico de los materiales leñosos carbonizados de cinco yacimientos arqueológicos de la Región de Murcia cuya secuencia cronológica cubre los últimos 3800 años, desde la Edad del Bronce hasta la época medieval. Los yacimientos estudiados son concretamente La Punta de los Gavilanes (Mazarrón), con ocupación desde la Edad del Bronce hasta mediados del siglo I a.C.; Barranco de la Viuda (Lorca), con un único momento de ocupación asociado al Bronce Argárico; el Balneario Romano de Archena, cuya cronología se sitúa en torno al siglo I d.C.; los materiales constructivos carbonizados del Teatro Romano de Cartagena y, finalmente, el enclave de los siglos XII y XIII localizado en la Calle Santa María nº 19 de Jumilla.Los resultados obtenidos se insertan en el contexto del Sureste de la Península Ibérica a partir de su discusión con las secuencias polínicas y antracológicas publicadas para esta zona. / This doctoral thesis contains the charcoal analysis of the charred materials from five archaeological sites of the Región de Murcia, whose chronological sequence covers the last 3800 years, from the Bronze Age to the medieval period. The studied sites are concretely Punta de los Gavilanes (Mazarrón), occupied from the Bronze Age to the I century BC; Barranco de la Viuda (Lorca), with one moment of occupation associated to the Argaric Bronze; Balneario Romano de Archena, whose chronology is around the I century AD; the charred building materials of the Teatro Romano de Cartagena and, finally, the medieval site (XII and XIII centuries) located in the Calle Santa Maria nº 19 of Jumilla.The results are inserted in the context of the Southeastern Iberian Peninsula by means of their discussion with published pollen and charcoal sequences from this zone.
5

Anatomia do lenho e do carvão de espécies arbóreas do Cerrado no Estado de São Paulo, Brasil /

Gonçalves, Thaís Alves Pereira, 1982- January 2010 (has links)
Resumo: A Antracologia é uma ciência que se baseia na anatomia da madeira para realizar a análise e identificação de carvão vegetal. No Brasil, ela visa tradicionalmente obter dados paleoecológicos e paleoetnobotânicos, mas também conservacionistas e tecnológicos. As análises antracológicas são possíveis porque a estrutura do lenho se mantém no carvão, entretanto, variações morfométricas podem ocorrer. O presente estudo visa contribuir para um melhor entendimento do efeito da carbonização no lenho através da análise estrutural da anatomia antes e após carbonização. A escolha de espécies do cerrado deveu-se ao forte impacto que este bioma sofre pela devastação e, principalmente, pelo uso de suas espécies para a produção de carvão vegetal. A anatomia do lenho e do carvão obtido a 400ºC foram analisadas em amostras de Copaifera langsdorffii, Dalbergia violacea, Dimorphandra mollis, Stryphnodendron polyphyllum, Caryocar brasiliense, Couepia grandiflora, Tapirira guianensis, Qualea grandiflora, Vochysia tucanorum e Pouteria torta, todas provenientes do cerrado e apresentando tipos anatômicos distintos. Todos os resultados quantitativos foram comparados estatisticamente. A contração anisotrópica nos carvões foi evidenciada principalmente na redução do diâmetro tangencial dos vasos, que ocorreu em 70% das espécies, mas não foi o suficiente para aumentar significativamente sua frequência; o diâmetro da abertura das pontoações intervasculares praticamente se manteve; a frequência dos raios aumentou ligeiramente; a altura e a largura dos raios variaram bastante, sendo que os raios mais largos contraíram mais que os estreitos; o parênquima axial manteve, no carvão, características semelhantes às do lenho; as fibras dos carvões perderam a distinção das camadas das paredes celulares presentes no lenho, mas mantiveram dimensões semelhantes... (Resumo completo clicar acesso eletrônico abaixo) / Abstract: Anthracology, or charcoal analysis, is a science based on wood anatomy. In Brazil it traditionally studies palaeoenvironment and palaeoethnobotany, as well as nature conservancy and forestry technology. Anthracological analyses are possible due to the maintenance of wood structure in charcoal. The present study aims to contribute to a better knowledge of carbonization on wood anatomy. Fresh and charred cerrado woods samples were analyzed. The Brazilian cerrado is highly impacted by devastation, while its species are widely used for charcoal production. The latter were charred under 400ºC. The selected species present different anatomical characteristics: Copaifera langsdorffii, Dalbergia violacea, Dimorphandra mollis, Stryphnodendron polyphyllum, Caryocar brasiliense, Couepia grandiflora, Tapirira guianensis, Qualea grandiflora, Vochysia tucanorum, and Pouteria torta. All the quantitative data between wood and charcoal were statistically analyzed. The anisotropic pattern of contraction in charcoals was evident as 70% of the species presented a reduction in vessels tangential diameter. Vessel frequency increase, however, was not statistically significant. Intervessel pits apertures diameters were very closely between wood and charcoal. Rays frequency slightly increased; rays height and width were extremely variable. Larger rays contract more than narrow ones. Axial parenchyma retained, in charcoal, the same dimensions and shape of wood. Charcoal fibres presented indistinct cell wall layering, but retained similar dimensions of wood fibres. Carbonization under 400ºC caused only few changes between wood and charcoal, corroborating the assumption that wood anatomy and anthracology are two closely related sciences / Orientador: Carmen Regina Marcati / Coorientador: Rita Scheel-Ybert / Banca: Graciela Ines B.de Muniz / Banca: Claudia França Barros / Mestre
6

Effets de la carbonisation oxygénée sur le signal isotopique (δ13C) du bois : vers une dendroclimatologie isotopique sur charbons archéologiques / Oxygenated carbonization on wood isotopic sigal (δ13C) : aim to dendroclimatic reconstructions on archeological charcoals

Baton, Franck 08 November 2017 (has links)
Les charbons de bois trouvés en contexte archéologique permettent de reconstituer les couverts forestiers passés et les pratiques sylvicoles associées. Le δ13C de ces charbons a été utilisé pour des reconstructions paléoclimatiques, cependant ses variations peuvent aussi être dues à la carbonisation. Afin de mieux contraindre, à l’échelle du cerne, les variations du δ13C du bois dues à la carbonisation, des carbonisations ont été faites avec des échantillons de chêne cadicufoliés en conditions proches des foyers domestiques. Une diminution du δ13C après la carbonisation a été observée. Cet effet est très variable, notamment en fonction du compartiment du bois considéré (aubier, duramen, bois initial, bois final). Ces mesures de δ13C ont été complétées par celles du taux de carbone montrant qu’il ne varie pas parallèlement au δ13C. De ce fait l’utilisation, prônée par certains travaux, du taux de carbone pour évaluer les variations de d13C suite à la carbonisation n’est pas pertinente. Cependant, les variations cerne à cerne et intracerne du δ13C ne sont pas significativement affectées par la carbonisation, et des reconstructions climatiques à partir du δ13C de bois carbonisés paraissent donc envisageables. Afin de tester cette approche cerne à cerne, plusieurs charbons archéologiques issus du site Néolithique de Chalain, dont les paléoclimats étaient bien documentés, ont été échantillonnés. Cette approche a été couplée à des mesures dendro-anthracologiques (largeurs des cernes, proportion du bois final, rayon de courbure et proportion de vaisseaux avec des thylles) afin de mieux comprendre les variations de δ13C mesurées, et de tenter de les coupler aux pratiques sylvicoles. Les valeurs de δ13C sont en accord avec les paléoclimats déjà inférés et les variations intra-cerne, ou saisonnières, de δ13C révèlent que la période froide était caractérisée par des saisons plus contrastées. Les mesures dendro-anthracologiques ont permis, entre autres, de préciser les variations de δ13C entre les différents compartiments du bois et de proposer une interprétation concernant les variations des pratiques sylvicoles en lien avec le climat. En conclusion, la carbonisation oxygénée provoque un abaissement des valeurs de δ13C du bois mais n’empêche pas les reconstructions paléo-climatiques à partir de leurs variations, notamment saisonnières, mesurées sur des charbons archéologiques. / Archeological charcoals are used for reconstructing past woodland vegetation and the related historical forest practices. Charcoals δ13C are used for paleoclimate reconstructions. To better constrain the use of δ13C, we investigated the effect of oxygenated carbonization on ring scale δ13C variations in oak wood. Results showed a significant decrease of δ13C values after carbonization. This effect, however, is highly variable according to the wood compartment considered: heartwood, sapwood, earlywood, or latewood. Carbon content measurements do not exhibit the same variations along oxygenated carbonization as observed with δ13C. Therefore, the use of carbon content for evaluating carbonization effects on δ13C, which is proposed by some authors, is not appropriate. Interannual and seasonal δ13C variations, however, are not significantly affected by oxygenated carbonization. Thus, paleoclimate reconstruction from charcoals δ13C appears possible. To test both ring scale variations, archeological charcoals were sampled from a climatically well documented Neolithic site of Chalain. Several dendro-anthracological parameters (latewood proportion, duraminization, charcoal-pith distance estimation) were characterized for a better understanding of δ13C variations, in order to integrate historical woodland practices and the climatic interpretations. Charcoal tree-rings exhibited width and δ13C significantly different between the two studied periods, in agreement with previously inferred climatic difference. Intra-ring δ13C suggested that the cool and moist climatic period also corresponded to higher seasonal contrast than the dryer climatic period. Dendro-anthracological parameters allow better understanding of δ13C variations between wood compartments and provide information on past woodland exploitations. To conclude, oxygenated carbonizations induce a decrease in wood δ13C values, but do not prevent the paleoclimate interpretations of δ13C variations in archeological charcoals.
7

Caracterização antracológica, físico-química, isotópica e molecular da Terra Preta do Sítio Arqueológico Porto, Santarém, PA / Anthrachological, physico-chemical, isotopic and molecular characterization of the Black Earth of the Porto Archaeological Site, Santarém, PA

Albuquerque, Álisson Rangel 12 April 2017 (has links)
Evidências arqueológicas indicam que as atividades humanas antigas nos habitats amazônicos transformaram significativamente a paisagem na vizinhança dos assentamentos. Um registro marcante são os solos afetados pelo homem pré-histórico e que apresentam cor escura, restos de material arqueológico (fragmentos cerâmicos e de artefatos líticos), fragmentos de carvão vegetal e alta fertilidade. O Sítio Porto Santarém, localizado a margem do rio Tapajós, possui todas as evidências desta ocupação e, por isso, foi escolhido como o objeto deste estudo. O objetivo aqui proposto consiste correlacionar os diferentes métodos analíticos e de interpretação (biológicos, isotópicos, moleculares e de imagem) para compreender os fatores de formação da Terra Preta no Sítio PA-ST-32. Os resultados indicaram um predomínio de cobertura florestal (C3) em todas as escavações durante a faixa de tempo abordada (400±30 a 3.830±30 anos AP), com enriquecimento isotópico em profundidade, como resultado, provavelmente, da dieta dos indígenas. Também, verificou-se um teor maior de carbono na TPI em relação ao perfil sem a camada antrópica, mas que mostraram valores similares (TIC%) de poliaromáticos oriundos da queima (carvão pirogênico). Foram identificados 100 fragmentos de carvão, onde 62% pertencem aos gêneros representativos da família Fabaceae. / Archaeological evidence indicates that ancient human activities in Amazonian habitats have significantly transformed the landscape in the vicinity of the settlements. A striking record are the soils affected by prehistoric man and which are dark in color, remains of archaeological material (ceramic fragments and lytic artifacts), fragments of charcoal and high fertility. The Porto Santarém Site, located on the banks of the Tapajós River, has all the evidence of this occupation and, therefore, was chosen as the object of this study. The objective here is to correlate the different analytical and interpretation methods (biological, isotopic, molecular and image) to understand the formation factors of Black Earth in the PA-ST-32 site. The results indicated a predominance of forest cover (C3) in all excavations during the time range (400 ± 30 to 3,830 ± 30 years BP), with deep isotopic enrichment, probably as a result of indigenous diet. Also, a higher carbon content was observed in TPI in relation to the profile without the anthropic layer, but they showed similar values (TIC%) of polyaromatics from the burning (pyrogenic charcoal). 100 charcoals fragments were identified, where 62% belong to the representative genus of the Fabaceae family.
8

Bois architecturés dans la construction rurale rupestre médiévale - Le cas de la basse Provence : architecture rupestre, anthracologie, dendrologie / Architectural woods in rupestrian, medieval construction - The lower Provence case's : rupestrian architecture, anthracolgy, dendrology

Venot, Claire 21 March 2016 (has links)
Pour la période médiévale, le bois en basse Provence calcaire un un sujet souvent évité, principalement à cause du manque de matériau ligneux non carbonisé conservé sur sites archéologiques.Cette thèse propose la mise en place d'une méthodologie, à la croisée des sciences humaines et sciences dures, qui permet de traiter de la question du bois d'ans l'architecture rupestre à partir de charbons prélevés en fouille, de traces d'encastrements, et d'analyses dendrochronologiques.Les traces d'encastrements visibles sur certains sites rupestres aident à la reconstitution des diamètres des bois utilisés en architecture. L'anthracologie identifie les espèces ligneuses utilisées sur les sites, et la dendrologie permet de proposer des âges par diamètre et espèce pour les arbres utilisés sur les sites. L'ensemble de ces données offre l'opportunité de proposer des reconstitutions de forêt utilisées dans l'habitat médiéval. / The lake of wood in archeological sites is a problem to work about wood and forest during the Middle ages. This work purpose a new methodological approach, to treat the wood question in rupestrian architecture. This study uses anthracological, dendrological, and architectural éléments.The print of wood in médieval walls gives the diametre of the trees used during construction. Anthracology gives the species used on archéological sites and the dendrological study purpose an age for each diametre and each species used on site.All these results give the opportunity to purpose forest reconstitution for lower Provence in Middle ages.
9

Anatomia comparada do lenho e do carvão aplicada na identificação de 76 espécies da floresta Amazônica, no estado do Pará, Brasil / Comparative anatomy of the wood and charcoal applied in the identification of 75 species of the Amazon forest in the state of Pará, Brazil

Albuquerque, Álisson Rangel 22 June 2012 (has links)
A antracologia, como ciência, tem como objetivo a análise da estrutura anatômica dos carvões vegetais arqueológicos e modernos direcionada para a paleoecologia, paleoetnobotânica, identificação das espécies, etc. No Brasil, a identificação de espécies florestais através da análise dos carvões vegetais atuais reveste-se de importante caráter conservacionista, por ser o maior produtor mundial de carvão vegetal, com grande parte produzida pela extração ilegal de madeira de florestas nativas. Com esse objetivo, no presente trabalho, foi avaliada a estrutura anatômica microscópica, a densidade e a contração do lenho e do carvão de 75 espécies da floresta Amazônica, estado do Pará. Os resultados evidenciaram para o parâmetro (i) anatômico, deformação de diferentes níveis dos elementos de vasos (e pontoações), das células do parênquima axial e radial e das fibras entre as espécies, (ii) físico, significativa variação da densidade da madeira e do carvão entre as espécies; as de madeira de maior densidade aparente apresentam carvão de maior densidade; (iii) contração, resultando na alteração da morfologia dos elementos anatômicos da madeira, com variações entre espécies. Além disto, os resultados permitiram (i) avaliar o efeito melhor do processo de carbonização nos parâmetros anatômicos e físicos da madeira, (ii) demonstrar a aplicação da antracologia como ferramenta na identificação de espécies tropicais e seu potencial no controle ambiental e na fiscalização, além de possibilitar a (iv) criação de uma coleção antracológica de referência, iniciando-se com 75 espécies de madeira e de carvão tropical. / The anthracology, as science, aims to analyze the anatomical structure of archaeological and modern vegetal charcoal applied for paleoecology, paleoetnobotanical, species identification, etc. In Brazil, the identification of forest species through analysis of vegetal charcoal is important to the nature conservation, considered that the country is the largest producer of charcoal produced, in part, by the illegal logging of native forests. With this objective, in the present study was evaluated the anatomical microcopical structure, density and contraction of wood and charcoal of 75 species of the Amazon forest, from Pará state. The results showed an (i) diferent levels of anatomical deformation of vessels (and pits), axial and radial parenchyma and fibers with variation between species, (ii) significant change of the wood and charcoal density between the tree species; the higher wood apparent density resulted in higher charcoal density, (iii) the retratibility resulted in alteration of the wood anatomical elements, with variations between species. Moreover, the results allowed (i) to evaluate the effect of the carbonization process in the wood anatomy and physical parameters, (ii) to demonstrate the application of anthracology as a tool for tropical species identification and its potential to environmental control and monitoring, in addition to enabling the (iv) creation of a anthracological collection, starting with 75 species of tropical wood and charcoal.
10

Vývoj vegetace v okolí Roztok u Prahy z pohledu antrakologické analýzy / Anthracological perspective on vegetation history in Roztoky u Prahy

Prach, Martin January 2019 (has links)
This thesis researches forest history and human impact on it in prehistory and early Middle Ages by means of soil charcoal analysis, i.e. pedoanthracology. It focuses on a site called "Roztocký háj" with long-term human settlement near Roztoky u Prahy in central Bohemia. Pedoanthracology brings information about past woody vegetation that is very local and without much anthropogenic influence. On the other hand, archeoanthracology focuses on charcoal originating from archeological excavations directly from human settlements. These charcoals are therefore formed by human behaviour and provide general view on woody vegetation in wider surroundings of the site. Comparing results of these two approaches in Roztoky is allowed by long-term archeological excavations. They provided previously analyzed and partially published charcoal dataset. Newly obtained pedoanthracological dataset brings finer spatial scale, allows to find out the effect of local conditions on the charcoal spectra and also allows identification of possible purposefully selected taxa in the archeoanthracological assemblage. Another part of this work describes present-day vegetation around the soil profiles and examines it's possible continuity with the past vegetation. 4 soil profiles provided quite species-rich (17 taxa) charcoal...

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