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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.
81

Ecological segregation inferred using chemical tracers and contamination assessment of five toothed whales in the Northwest Iberian Peninsula / Ségrégation écologique déterminée par des traceurs chimiques et estimation de la contamination de cinq cétacés odontocètes du nord-ouest de la pénisule ibérique

Mendez Fernandez, Paula 30 November 2012 (has links)
Le premier objectif de ce travail de thèse était de déterminer quel est le degré de ségrégation écologique entre cinq espèces sympatriques de cétacés odontocètes (i.e. le dauphin commun Delphinus delphis, le marsouin commun Phocoena phocoena, le grand dauphin tursiops truncatus, le dauphin bleu et blanc Stenella coeruleoalba et le globicéphale noir Globicephala melas) fréquentant l’aire marine restreinte et très productive du Nord-Ouest de la Péninsule Ibérique (NOPI). Pour cela, des paramètres chimiques ont été analysés dans les tissus biologiques, en tant que “ méthode alternative ” pouvant refléter de façon précise le régime alimentaire et l’habitat de ces animaux à différents échelles de temps d’intégration, et ainsi compléter les informations apportées par des méthodes plus traditionnelles tels que l’analyse des contenus stomacaux ou des fèces, ou encore les données d’observations en mer. Le second objectif de ce travail était d’évaluer l’état de contamination de ces espèces, pour acquérir une base de données de référence complète les concernant et estimer le risque toxicologique auquel elles peuvent faire face. Dans ce contexte, les éléments traces, les isotopes stables du carbone et de l’azote, et les polluants organiques persistants (POPs) sont les paramètres chimiques qui ont été sélectionnés pour répondre aux objectifs fixés.Dans un premier temps, les paramètres chimiques ont été utilisés comme traceurs écologiques des populations (ou de segments de population), procurant une image du régime alimentaire et de l’habitat des espèces à différentes échelles de temps. Nous avons calculé que le réseau trophique du NOPI avait cinq niveaux trophiques, au sein duquel les espèces étudiées occupaient les plus hautes positions, comprises entre 4,3 à 5,3, et sans qu’il y ait de différence significative de position trophiques entre les espèces. Alors que l’analyse d’un seul paramètre chimique ne permettait pas ségréger les cinq espèces, les informations apportées par l’analyse de plusieurs traceurs de long terme (i.e. rapport des isotopes stables du carbone et de l’azote dans les dents et concentrations de cadmium dans les reins) ont révélé une ségrégation de leur niche écologique dans deux des dimensions possibles (les dimensions trophique et spatiale). Cependant, les variations pouvant survenir d’une année sur l’autre ou saisonnières n’ont pas pu être étudiées, excepté pour le dauphin commun, et un chevauchement temporaire des niches ne peut donc pas être totalement exclu. De plus, nous avons montré que les profils de polychlorobiphényles (PCBs) pouvaient être un traceur pertinent de l’écologie trophique d’espèces taxinomiquement proches, en permettant une séparation fine des espèces telles que le marsouin commun et le dauphin bleu et blanc, d’après les différents profiles d’accumulation de ces deux espèces.Dans un second temps, l’état de contamination des espèces dans la zone d’étude a été évalué. Les concentrations ont été interprétées à la lumière des facteurs biologiques et écologiques pouvant influencer ces concentrations, et la bioaccumulation des éléments traces s’est révélée moins prévisible que celle des POPs. Le grand dauphin et le marsouin commun présentaient les concentrations de PCBs les plus élevées par rapport aux autres cétacés odontocètes du NOPI et par rapport à d’autres individus des eaux adjacentes de l’Atlantique Nord-Est.Les résultats principaux de ce travail de thèse ont mis en évidence la pertinence d’utiliser ces paramètres chimiques comme traceurs écologiques, et leur utilité dans la compréhension de la structure et le fonctionnement des écosystèmes à travers le rôle des prédateurs supérieurs. En combinant ces résultats à des informations concernant les activités anthropiques, ce travail peut contribuer au développement et à l’implémentation de mesures de gestion pour ces cinq espèces de cétacés odontocètes du NOPI. / The first objective of this PhD was to determine the degree of ecological segregation between five sympatric species of toothed whales (i.e. common dolphin Delphinus delphis, harbour porpoise Phocoena phocoena, bottlenose dolphin Tursiops truncatus, striped dolphin Stenella coeruleoalba and long finned pilot whale Globicephala melas) inhabiting a restricted and highly productive area, the North West Iberian Peninsula (NWIP). To this end, chemical parameters analyses were used as an “alternative method” of assessing diet and habitat of these animals over different periods of integration, complementing the information given by traditional methods of investigation such as stomach contents, faeces analyses and field observations. The second objective was to evaluate the contamination status of these species in order to estimate the toxicological risk these populations face and to complete the existing database. In this context, trace elements, carbon and nitrogen stable isotopes, as well as persistent organic pollutants (POPs) were selected as chemical parameters for our investigations.Firstly, the chemical parameters were used as ecological tracers of populations (or parts of populations) by drawing an image of the diet and habitat of the species at different time scales. We estimated that the food web has five trophic levels, with toothed whales occupying the top positions, with no significant difference in trophic positions among them, ranging from 4.3 to 5.3. While the analysis of a single chemical parameter did not completely segregate between the five species, the information gained by combining the analyses of several long-term ecological tracers (i.e. nitrogen and carbon stable isotopes in teeth and renal cadmium concentrations) revealed ecological niche segregation in two dimensions of this niche (the trophic and the spatial dimensions). However, year-to-year or seasonal variations could not be investigated, except for in common dolphin, and thus temporary overlap cannot be excluded. Additionally, we showed that polychlorinated biphenyls (PCBs) profiles could be a relevant tracer of the foraging ecology of taxonomically close species, allowing a fine separation of the species as result of their different patterns. This was particularly clear for the harbour porpoise and striped dolphin.Secondly, the contamination status of the species in this area was evaluated, with concentrations interpreted in the light of biological and ecological factors. But the bioaccumulation of trace elements appeared to be less predictable than that of POPs. Bottlenose dolphins and harbour porpoises were found to have higher PCBs concentrations than the rest of the analysed NWIP toothed whales, as well as those of adjacent NE Atlantic waters.The main results of this PhD highlight the relevance of exploiting these chemical parameters as ecological tracers, as well as their usefulness in the comprehensive study of structure and function of ecosystems through the role of top predators. Combined with the information on anthropogenic activities, this work can also contribute to the development and implementation of management plans and mitigation measures for these five species of toothed whales in the NWIP.
82

Enrique de Villena e seu tratado Arte Cisoria: um estudo sobre a composição dos saberes medievais ibéricos

Vidal, Henrique Yukio Okano 29 May 2013 (has links)
Made available in DSpace on 2016-04-28T14:16:18Z (GMT). No. of bitstreams: 1 Henrique Yukio Okano Vidal.pdf: 725083 bytes, checksum: 233a45b0cbccade161540de2da2994b2 (MD5) Previous issue date: 2013-05-29 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The present dissertation discusses the work of Enrique de Villena (1348-1434), as it provides one of the best examples of the type of knowledge developed at that time in the Iberian Peninsula based on the contributions of several older civilizations. In addition to a scholar and prolific writer, Villena was a noble traveller, and a controversial character, to the point of becoming a myth. We analyzed the various interpretative layers corresponding to the historiography, which tended to focus on Villena s mythical image, as a rule. The present study also includes an analysis of Arte Cisoria, admittedly written by him, and the Alchemical Letter, whose authorship is controversial. By thus proceeding, a more complete and balanced image of Villena s work becomes possible / A presente dissertação está focada na obra de D. Enrique de Villena (1384-1434). Essa obra reflete, como poucas outras da época, a rica composição de saberes que a Península Ibérica absorveu e desenvolveu, a partir de culturas anteriores. Além de estudioso e escritor prolífero, Villena foi um nobre viandante e figura controversa, tornando-se uma lenda. Analisaremos as diversas camadas de interpretação feitas pela historiografia e, em geral, centradas nessa imagem lendária de Villena. Será também analisada a Arte Cisoria, obra reconhecidamente de sua autoria, ao lado da chamada Carta Alquímica que, para muitos, lhe teria sido falsamente atribuída. Com isso, pretendemos encontrar elementos para uma verificação mais completa e equilibrada da obra de Villena
83

Diccionario das antiguidades de Portugal: história e edição crítica de um manuscrito (séculos XVIII e XIX) / Diccionario das Antiguidades de Portugal: history and critical edition of a manuscript (XVIII and XIX centuries)

Daniel Carvalho de Paula 14 December 2015 (has links)
Nosso trabalho consiste em produzir uma edição crítica e investigar a história, modo de composição e transmissão da obra inédita Diccionario das Antiguidades de Portugal. Inicialmente, este trabalho se dedicou a uma cópia manuscrita do século XIX, depositada no Instituto Histórico e Geográfico Brasileiro. A análise das referências bibliográficas de cada verbete e sistema de escrita nos convenceu de que a obra original teria sido composta no século XVIII. O estudo desta cópia levou-nos a encontrar o manuscrito original localizado na Academia das Ciências de Lisboa, sob a autoria de Pedro José da Fonseca (1737-1816), professor do Colégio dos Nobres, membro fundador e diretor da tipografia da Academia, fundada em 1779. Manoel José Maria da Costa e Sá, Oficial Maior da Secretaria dos Negócios da Marinha e Ultramar, é quem entendemos ser o autor da cópia manuscrita do IHGB, sua trajetória é muito desconhecida e pudemos aclará-la. Também tratamos da participação nessa história do Conselheiro Antônio Menezes Vasconcellos de Drummond, que trouxe para o IHGB a cópia feita pelo amigo Costa e Sá. Uma rede transatlântica envolvendo homens de letras em Portugal e no Brasil se torna clara através deste estudo, mostrando que o Diccionario das Antiguidades de Portugal é uma sólida janela através da qual podemos muito bem mirar a história da Cultura Escrita nos séculos XVIII e XIX. / Our work consists in the production of a critical edition and the investigation of the history, composition, and transmission of the unpublished Diccionario das Antiguidades de Portugal (Dictionary of Antiquities of Portugal). Initially, our work was focused on a single manuscript, a copy from the 19th century, deposited in the Brazilian Historical and Geographical Institute (IHGB). The analysis of the bibliographic references pertaining to each entry of the dictionary and the writing system convinced us that the original work was written in the 18th century. The study of this copy led us to find the original manuscript located in the Lisbon Academy of Sciences, under the authorship of Pedro José da Fonseca (1737-1816), who was professor at the College of Nobles, founding member and director of typography in the Academy, founded in 1779. Manoel José Maria da Costa e Sá, Higher Official at the Secretary for the Navy and Overseas Affairs, is the man who we understand to be the author of the manuscript copy belonging to the IHGB; his trajectory is quite unclear and we were able to shed some light upon it. We have also approached the participation in the story of Counselor Antônio Menezes Vasconcellos de Drummond; he brought to the IHGB the copy made by his friend Costa e Sá. A transatlantic network involving Portuguese and Brazilian men of letters becomes clear through this study, rendering it patent that the Diccionario das Antiguidades de Portugal is a steadfast window throughout which we can very well gaze upon the history of Literate Culture in the 18th and 19th centuries.
84

No limiar dos Impérios: projetos, circulações e experiências na fronteira entre a Capitania do Rio Negro e a Província de Maynas (c.1780-c.1820) / On the threshold of Empires: projects, circulations and experiences in the border area between the Captaincy of Rio Negro and the Province of Maynas (1780-1820)

Carlos Augusto de Castro Bastos 24 September 2013 (has links)
Esta tese analisa as políticas destinadas à área fronteiriça entre a Capitania do Rio Negro e a Província de Maynas, bem como as circulações e experiências que caracterizaram esse espaço amazônico. O recorte cronológico abarca, inicialmente, os trabalhos de demarcação de limites empreendidos por representantes das Coroas espanhola e portuguesa, na década de 1780, compreendendo ainda os anos de crise política do Antigo Regime e a eclosão dos movimentos de independência na América nas primeiras décadas do século XIX. Nesse trabalho, privilegia-se uma análise que atente para as relações transfronteiriças, os impactos no espaço em questão das grandes transformações vivenciadas pelos impérios ibéricos e as leituras, interpretações e ações gestadas pelos sujeitos que habitavam essa fronteira ibero-americana. / This thesis examines the policies concerning the border area between the Captaincy of Rio Negro and the Province of Maynas, as well as the circulations and experiences that characterize this Amazonian space. Initially, the chronological period considered includes the demarcation of boundaries undertaken by representative members of the Spanish and Portuguese crowns in the 1780s, the years of political crisis of the Old Regime, and the outbreak of the independence movements in America in the early decades of the XIXth century. In this work, the analysis attempts to cross-border relations, the impacts this space has suffered due to great changes experienced by the Iberian empires, and also, the readings, interpretations and actions generated by the subjects who inhabited this Iberoamerican frontier.
85

Fea, velha, sandia: imagens da mulher nas cantingas de escárnio e maldizer galego-portuguesas / Ugly, old, crazy: womens images in the galician-portuguese cantigas de escárnio e maldizer

Cerchiari, Candice Quinelato Baptista 31 March 2009 (has links)
O objetivo desta pesquisa é buscar as imagens da mulher nas cantigas de escárnio e maldizer galego-portuguesas. Para caracterizar o ambiente de produção dessa poesia, usaremos como contraponto às fontes literárias uma documentação de caráter mais objetivo e descritivo: compilações legais peninsulares, As Sete Partidas, de Leão e Castela, e o Livro das Leis e Posturas e as Ordenações Afonsinas, de Portugal, numa tentativa de compreender os problemas concretos relativos ao papel social da mulher no âmbito do casamento e da herança que ensejaram a composição das cantigas satíricas. Por meio dos comentários feitos pelos trovadores, dirigidos a mulheres ou a homens a elas relacionados, buscaremos compreender os juízos de valor que norteiam sua visão dos vícios e das virtudes da figura feminina e, assim, identificar facetas da mulher que, vistas à luz do momento histórico-literário que procuramos caracterizar, perfarão nosso objetivo de descrever a figura da mulher que nos foi legada por meio das cantigas satíricas ibéricas medievais. / The goal of this research is to find womens images in the Galician-Portuguese cantigas de escárnio e maldizer. In order to characterize the ambience of production of this kind of poetry, it will be used as counterpoint to the literary fonts a more objective and descriptive documentation: the peninsular legal compilations, As Sete Partidas, from Leon and Castille, and the Livro das Leis e Posturas and the Ordenações Afonsinas, from Portugal, as an attempt to understand concrete problems related to womens social part as it is pertinent to marriage and inheritance, which instigated the writing of the satirical ballads. By means of the comments made by the troubadours, about women or men related to them, we shall seek comprehension of the value-judgments which guide their vision of the vices and virtues of the feminine figure and, thus, identify the woman facets that, seen in light of the historical-literary moment characterized, will make our objective to describe the womens images bequeath to us by the Iberian medieval satiric ballads.
86

Seismic-Reflection and Seismic-Refraction Imaging of the South Portuguese Zone Fold-and-Thrust Belt

Schmelzbach, Cedric January 2007 (has links)
The South Portuguese Zone (SPZ), which host world-class massive sulphide deposits, forms the southern fold-and-thrust belt of the Iberian Variscan orogeny. This thesis focuses on seismic-reflection and seismic-refraction processing efforts on a subset of the IBERSEIS deep seismic-reflection data set aiming at resolving the SPZ upper crust in high resolution. A comparison of different crooked-line seismic-reflection imaging schemes showed that a processing sequence involving dip-moveout corrections, a common-midpoint projection, and poststack time migration of common-offset gathers provided the most coherent images considering the crooked acquisition geometry. Correlation with surface-geological data allows four units of different reflection character to be identified: the ~0–2 km deep Upper Carboniferous Flysch group, the highly reflective ~2–4 km thick and up to ~5 km deep Volcano-Sedimentary Complex (VSC) group, and two deep Paleozoic metasedimentary units, with the shallower Phyllite-Quartzite group exposed in an antiform. Prominent diffracted energy was enhanced using a modified Kirchhoff imaging routine. High reflectivity and distinct diffractions mark extensive dike bands at 6–12 km depth, possibly related to the intense hydrothermal activity that led to the formation of the ore-bearing VSC group. Source-generated noise obscures potential signals from depths shallower than ~500m depth on the seismic-reflection sections. P- and SV-wave first-arrival traveltimes were inverted for velocity models imaging the shallowest crust. Overall, the velocity models correlate well with surface-geological data marking high (>5.25 km/s) and uniform P-velocities for the Flysch unit in the southern SPZ. A prominent P-wave low-velocity body (~4.5 km/s) is resolved where the Phyllite-Quartzite unit forms the core of an antiform. P-velocities fluctuate the most in the northern SPZ with Flysch group units exhibiting high velocities (>5.25 km/s) and VSC group bodies showing intermediate velocities (~5 km/s). Low VP/VS-ratios (~1.8) computed for the southern profile part are interpreted as less deformed Flysch-group units, whereas high VP/VS-ratios (~1.9) indicate fractured units.
87

Uso de los coleópteros acuáticos ibéricos en la conservación de la biodiversidad

Sánchez Fernández, David 01 July 2008 (has links)
La tesis aborda el problema de la conservación de la biodiversidad acuática en la Península Ibérica e Islas Baleares desde una doble perspectiva, estableciendo prioridades de conservación para espacios y especies utilizando inventarios de coleópteros acuáticos. En primer lugar, se evalúa si los coleópteros acuáticos pueden ser utilizados como buenos indicadores de biodiversidad en ecosistemas acuáticos mediterráneos. Posteriormente, se seleccionan áreas prioritarias para la conservación de la biodiversidad acuática usando coleópteros como indicadores. Se crea una base de datos de coleópteros acuáticos ibéricos y se evalúa tanto el esfuerzo de muestreo, como la cantidad y naturaleza de los posibles sesgos de los datos. Se ha obtenido una función basada en variables ambientales y espaciales capaz de predecir la distribución de la riqueza de especies en la Península Ibérica. Por último se identifican las especies endémicas mas amenazadas, y se evalúa la efectividad de la Red Natura 2000 en su protección. / This thesis comprises the problem of freshwater biodiversity conservation in the Iberian Peninsula and Balearic Islands using inventories of water beetles as surrogates of biodiversity. The thesis involves different approaches and methods from the double perspective of setting conservation priorities for species and areas. Firstly, the use of water beetles as reliable biodiversity indicators in Maditerranean aquatic ecosystems was assessed. Then, areas for freshwater biodiversity conservation at regional scale were selected using water beetles as biodiversity surrogates. Afterwards, a database of Iberian water beetles was compiled. The survey effort, the degree of geographical coverage and the amount and nature of bias in this database were assessed. Subsequently, a function based on environmental and spatial variables able to predict species richness distribution in the Iberian Peninsula and Balearic Islands were obtained. Lastly, the most threatened endemic water beetles were identified and the effectiveness of existing reserve network (Natura 2000) in protecting them was evaluated.
88

Conservación de la biodiversidad acuática en el Sureste Ibérico: métodos y estrategias a partir de inventarios de coleópteros acuáticos

Abellán Ródenas, Pedro 18 December 2006 (has links)
La presente tesis doctoral aborda distintas estrategias y metodologías en el contexto de la conservación de la biodiversidad de ecosistemas de aguas continentales en el Sureste Ibérico, utilizando inventarios de coleópteros acuáticos. En primer lugar, se propone un método para evaluar la vulnerabilidad de especies y para asignar prioridades de conservación a especies y poblaciones de insectos. A continuación, se compara la eficacia de diferentes métodos de selección de áreas y se estudia el rendimiento de las áreas protegidas en el contexto de la conservación de la biodiversidad de sistemas acuáticos. Por otro lado, se testa el comportamiento de tres índices de diferenciación taxonómica con relación a los niveles de impacto antrópico en aguas continentales. Finalmente, se estudia la variación genética y la filogeografía de Ochthebius glaber, un escarabajo acuático raro y amenazado endémico de arroyos hipersalinos del sur y sureste de la Península Ibérica.
89

Ecological segregation inferred using chemical tracers and contamination assessment of five toothed whales in the Northwest Iberian Peninsula

Mendez Fernandez, Paula 30 November 2012 (has links) (PDF)
The first objective of this PhD was to determine the degree of ecological segregation between five sympatric species of toothed whales (i.e. common dolphin Delphinus delphis, harbour porpoise Phocoena phocoena, bottlenose dolphin Tursiops truncatus, striped dolphin Stenella coeruleoalba and long finned pilot whale Globicephala melas) inhabiting a restricted and highly productive area, the North West Iberian Peninsula (NWIP). To this end, chemical parameters analyses were used as an "alternative method" of assessing diet and habitat of these animals over different periods of integration, complementing the information given by traditional methods of investigation such as stomach contents, faeces analyses and field observations. The second objective was to evaluate the contamination status of these species in order to estimate the toxicological risk these populations face and to complete the existing database. In this context, trace elements, carbon and nitrogen stable isotopes, as well as persistent organic pollutants (POPs) were selected as chemical parameters for our investigations.Firstly, the chemical parameters were used as ecological tracers of populations (or parts of populations) by drawing an image of the diet and habitat of the species at different time scales. We estimated that the food web has five trophic levels, with toothed whales occupying the top positions, with no significant difference in trophic positions among them, ranging from 4.3 to 5.3. While the analysis of a single chemical parameter did not completely segregate between the five species, the information gained by combining the analyses of several long-term ecological tracers (i.e. nitrogen and carbon stable isotopes in teeth and renal cadmium concentrations) revealed ecological niche segregation in two dimensions of this niche (the trophic and the spatial dimensions). However, year-to-year or seasonal variations could not be investigated, except for in common dolphin, and thus temporary overlap cannot be excluded. Additionally, we showed that polychlorinated biphenyls (PCBs) profiles could be a relevant tracer of the foraging ecology of taxonomically close species, allowing a fine separation of the species as result of their different patterns. This was particularly clear for the harbour porpoise and striped dolphin.Secondly, the contamination status of the species in this area was evaluated, with concentrations interpreted in the light of biological and ecological factors. But the bioaccumulation of trace elements appeared to be less predictable than that of POPs. Bottlenose dolphins and harbour porpoises were found to have higher PCBs concentrations than the rest of the analysed NWIP toothed whales, as well as those of adjacent NE Atlantic waters.The main results of this PhD highlight the relevance of exploiting these chemical parameters as ecological tracers, as well as their usefulness in the comprehensive study of structure and function of ecosystems through the role of top predators. Combined with the information on anthropogenic activities, this work can also contribute to the development and implementation of management plans and mitigation measures for these five species of toothed whales in the NWIP.
90

Utilisation des isotopes stables et radiogéniques du strontium pour tracer la provenance des bois : application à des épaves sous-marines / Use of stable and radiogenic strontium isotopes to trace the origin of woods : application to wood from shipwrecks

Hajj, Fadi 14 November 2017 (has links)
Au début des temps modernes (16ème - 18ème siècles), la construction de grands navires était primordiale pour le développement des rencontres culturelles dans ce qui est devenu l'âge de la découverte et de l'expansion européenne. L’Espagne était une des grandes puissances de l’époque. Le projet européen « ForSEAdiscovery » cherche dans ce contexte à répondre aux questions clés suivantes : les ressources forestières ibériques de l’époque soutenaient-elles la demande croissante de bois, ou bien ce bois était-il importé d’autres pays ? Si ces bois ne provenaient pas de l’Espagne, comment les réseaux de commerce étaient-ils organisés ? Ce projet aborde ces questions à travers un programme de recherche multidisciplinaire et innovant pour améliorer la compréhension de notre passé historique et de notre patrimoine culturel, et développer notre connaissance sur l'utilisation passée des ressources en bois pour la construction navale. L'objectif de cette thèse, qui s’insère dans ce projet, est d’identifier la provenance des bois utilisés dans la construction navale ibérique en utilisant des traceurs géochimiques. L’hypothèse est que les arbres se développant sur des roches et des sols contrastés possèdent des signatures géochimiques spécifiques héritées des roches. Les signatures isotopiques en strontium (87Sr/86Sr) peuvent notamment être des indicateurs de provenance géographique. Dans ce contexte, la démarche suivie dans la thèse a consisté à caractériser la signature isotopique en Sr dans des bois d'épaves de bateaux et dans les bois d’arbres actuels, les sols et roches prélevés dans les principaux peuplements forestiers espagnols pointés comme lieux de production des bois entre le 16ème - 18ème siècles. Les signatures en δ88/86Sr, traceur peu connu encore, ont également été caractérisées dans les échantillons. Les types et les âges des roches ont été caractérisés et les liens entre les rapports isotopiques 87Sr/86Sr et δ88/86Sr dans les roches, sols et arbres ont été étudiés sur les sites espagnols échantillonnés. La signature locale des sites espagnols potentiels de provenance de bois a été déterminée. Nos résultats mettent en évidence que le rapport isotopique 87Sr/86Sr dans les arbres reflète la signature de la fraction échangeable des sols sur lesquels ils croissent alors que le δ88/86Sr est affecté par le fractionnement, les isotopes légers (86Sr) étant préférentiellement incorporés dans les arbres laissant la fraction échangeable du sol enrichie avec les isotopes lourds (88Sr). Ce fractionnement observé pour les chênes, n’est pas marqué dans le bois des pins suggérant que le fractionnement isotopique durant le transfert du Sr entre le sol et l’arbre est dépendant de l’espèce. La contamination des bois d’épaves par les éléments marins a été identifiée. Le Sr marin se retrouve notamment sous forme adsorbée ou dans la structure des minéraux précipités dans les bois immergés. Différentes expériences d’extractions ont été testées et un protocole adapté a été développé pour extraire les éléments marins et retrouver la signature originelle du bois archéologique. Nous avons réussi à valider un protocole d’extraction et retrouver la signature originelle d’un échantillon de bois d’épave. Ce résultat souligne le potentiel et l’importance d’une nouvelle méthode combinant 87Sr/86Sr et δ88/86Sr pour des futures études de provenance de bois ou autres matériaux. Cependant, nos résultats indiquent également que beaucoup de nos échantillons de bois archéologiques n’ont pas conservé leur Sr originel. Partant de ce constat, des préconisations sont proposées pour améliorer la possibilité d’utilisation de ce traceur dans les études futures de provenance de bois archéologiques sous-marins / In the Early Modern Age (16th - 18th centuries), the construction of ocean-going ships was paramount to the development of cultural encounters in what became the Age of Discovery and European expansion. Spain was one of the biggest forces of that time. The European project “ForSEAdiscovery” seeks answers in this context to the following key questions: Could Spanish forest resources sustain the increasing demand of timber, or were the wood imported from elsewhere? If Spanish forests were not the only wood supplier, how were the trade networks organized? This project will address these questions through a multidisciplinary and innovative training research program to improve the understanding of our historical past, our cultural heritage, and our knowledge of the use of resources for shipbuilding. The objective of this PhD thesis, taking part of this project, is to identify the provenance of the Iberian shipbuilding wood using geochemical tracers. The hypothesis is that trees growing on contrasted rocks and soils have specific geochemical signatures, which can be an indicator of geographic provenance. In this context, the Sr isotopic signature (87Sr/86Sr) was characterized in shipwreck wood samples and wood from living trees, soils and rocks collected from the Spanish forest stands indicated as potential source of wood between the 16th - 18th centuries. The δ88/86Sr signatures were also characterized in the samples. The rock types and ages were characterized at the selected sites and the link between the 87Sr/86Sr and δ88/86Sr in rocks, soils and trees was studied on the sampled Spanish sites. The local signature of Spanish potential sites was determined for provenance of wood. Our results indicate that 87Sr/86Sr isotope ratios in trees reflect the signature of the corresponding soil exchangeable pool while δ88/86Sr was shown to be affected by mass-dependent fractionation with trees taking up lighter (86Sr) isotopes, leaving the soil exchangeable pool enriched with the heavier isotopes (88Sr). This fractionation observed for oak trees, was not found in pines suggesting that the isotopic fractionation during tree uptake is species dependent. The contamination of wood from shipwrecks by seawater elements was identified. Marine Sr was found to be adsorbed on the wood or included in the precipitated minerals in the waterlogged wood. Several extraction experiments were tested and an adapted protocol was developed to extract the seawater elements and retrieve the original signature of the archaeological wood. We succeeded to validate an extraction protocol and retrieve the original signature of one wood sample. This result underline the potential and importance of a new method combining 87Sr/86Sr and δ88/86Sr values for future provenance studies on wood or other materials. However, our results also indicated that most of our shipwreck wood samples did not conserve their original Sr. Therefore, preconizations were suggested in order to extend the use of this tracer in future provenance studies on archaeological wood from shipwrecks

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