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Estudo da microbiota edáfica da área cárstica de São Desidério-BA e avaliação do seu potencial celulolítico para possíveis aplicações em microbiologia ambientalPaula, Caio César Pires de 11 February 2014 (has links)
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Previous issue date: 2014-02-11 / Financiadora de Estudos e Projetos / The cave environments are oligotrophic and have specific characteristics that determine the native microbiota. Few studies have investigated the composition and function of soil microbiota of subterranean environments. This study aimed to expand the knowledge on the cave microbiota, discuss the functional role of the microbiota in these environments, isolate and select fungal strains with biotechnological potential for the degradation of cellulose. Soil epigean environment and two poins inside the cave Catão, São Desiderio BA, were sampled. The amount of total organic carbon, carbon and nitrogen in the microbial biomass and the microbial density was evaluated in the soil. All strains were evaluated for the activities of endoglucanase, β-glucosidase and total cellulase by submerged fermentation. Of these three strains of Aspergillus strains, one strain standard, and a Penicillium the process of solid state fermentation using wheat bran as substrate were selected. We observed a significant difference between epigeal and subterranean environment in relation to physical, chemical and biological soil parameters evaluated. We obtained 20 isolates belonging of the genus Aspergillus (SDC1.1, SDC 1.2, SDC 1.4, SDC 1.6, SDC 2.4, SDC 2.6, SDC 2.8, SDC 2.10, SDC 2.11, SDC 2.12), Penicillium (SDC 1.3, SDC 1.7, SDC 2.2, SDC 2.7, SDC2.9, SDC 2.13), Trichoderma (SDC 2.3), Scopulariopses (SDC 2.1) e Purpureocillium (SDC 2.5). Of all isolates showed 90% cellulolytic activity. During the submerged fermentation endoglucanase activity showed maximum values of 6.39 IU/mL in a strain of Aspergillus sp6 and maximum total cellulase activity was 1.7 IU/ml for Aspergillus sp8 strain. The strain Aspergillus sp6 showed maximum β- glucosidase activity of 13.67 IU/mL. Compared to solid-state fermentation, the Aspergillus sp6 and Aspergillus sp8 strains stood out compared to mutant strain Aspergillus niger 3T5B8, with values of endoglucanase and total cellulase activity higher whole with a lower protein content in their enzymatic extracts. From these resulados, we conclude that the cave environment presents singularities compared to epigean environment which probably allows you to select naturally microorganisms that use alternative sources for energy and nutrients. / Os ambientes cavernícolas são oligotróficos e possuem características específicas que determinam a microbiota local. Poucos estudos têm investigado a composição e funcionalidade da microbiota edáfica de ambientes subterrâneos. Este trabalho teve como objetivo ampliar o conhecimento sobre a microbiota cavernícola, discutir o papel funcional da microbiota nesses ambientes, isolar e selecionar linhagens fúngicas com potencial biotecnológico para a degradação de celulose. Foram coletadas amostras de solo do meio epígeo e de dois pontos no interior da caverna do Catão, São Desidério-BA. Nas amostras foram avaliadas as quantidades de carbono orgânico total, a densidade microbiana, carbono e nitrogênio da biomassa microbiana, bem como isoladas linhagens de fungos filamentosos. Todas as linhagens foram avaliadas quanto as atividades de endoglucanase, celulase total e β-glucosidases por meio de fermentação submersa. Dessas linhagens foram selecioandas três linhagens de Aspergillus, sendo uma linhagem padrão, e uma linhagem de Penicillium para o processo de fermentação em estado sólido, utilizando farelo de trigo como substrato. Observamos uma diferença significativa entre o meio epígeo e subterrâneo em relação aos parâmetros físicos, químicos e biológicos do solo avaliados. Obtivemos 20 isolados pertencentes aos gêneros Aspergillus (SDC1.1, SDC 1.2, SDC 1.4, SDC 1.6, SDC 2.4, SDC 2.6, SDC 2.8, SDC 2.10, SDC 2.11, SDC 2.12), Penicillium (SDC 1.3, SDC 1.7, SDC 2.2, SDC 2.7, SDC2.9, SDC 2.13), Trichoderma (SDC 2.3), Scopulariopses (SDC 2.1) e Purpureocillium (SDC 2.5). De todos os isolados 90% apresentaram atividade celulolítica. Durante a fermentação submersa a atividade endoglucanase apresentou valores máximos de 6,39 IU/mL em uma linhagem de Aspergillus sp6 e a atividade máxima de celulase total foi de 1,7 IU/mL para uma linhagem Aspergillus sp8. A linhagem Aspergillus sp6 apresentou atividade β-glucosidase máxima de 13,67 IU/mL. Em relação a fermentação em estado sólido, as linhagens Aspergillus sp6 e Aspergillus sp8 se destacaram em relação a linhagem padrão Aspergillus niger 3T5B8, com valores de atividade endoglucanase e celulase total superiores e com um menor conteúdo proteico em seus extratos enzimáticos. A partir desses resultados, concluímos que o ambiente cavernícola apresenta singularidades em relação ao meio epígeo e que provavelmente permite selecionar naturalmente microrganismos que utilizam fontes alternativas para obtenção de energia e nutrientes.
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Exploring palaeoaridity using stable oxygen and carbon isotopes in small mammal teeth : a case study from two Late Pleistocene archaeological cave sites in Morocco, North AfricaJeffrey, Amy January 2016 (has links)
Revised chronologies from Moroccan cave sites have raised questions concerning the timing of changes in human cultural behaviour in relation to past climate shifts. However, many of the inferences about past moisture regimes are based on external records. Therefore, this thesis aimed to develop a palaeoclimate record using oxygen and carbon isotope values (d18O and d13C) in Gerbillinae (gerbil) teeth from two Late Pleistocene cave sites, El Harhoura 2 and Taforalt, in Morocco. Since small mammals are not commonly used to construct proxy climate records, a modern isotope study was undertaken in northwestern Africa to understand the influences on the stable isotope composition of small mammal tissues in semi-arid and arid settings. The results from the modern study show that d18O composition of gerbil teeth is strongly correlated with mean annual precipitation (MAP), and therefore in arid settings reflects moisture availability. Predictably, the d13C values of the gerbil teeth reflected C3 and C4 dietary inputs, but arid and mesic sites could not be distinguished because of the high variability displayed in d13C. The d18O isotope-based MAP reconstructions suggest that the Mediterranean coastal region of North Africa did not experience hyper-arid conditions during the Late Pleistocene. The d13C values of the gerbil teeth show that C3 vegetation dominated in the Late Pleistocene, but there was a small amount C4 vegetation present at Taforalt. This indicates that small mammals are extremely sensitive to discreet shifts in past vegetation cover. Both the modern and archaeological studies demonstrated that the isotope values of molars and incisors differed. The results indicate that tooth choice is an important consideration for applications as proxy Quaternary records, but also highlights a new potential means to distinguish seasonal contexts. Comparisons of proxy climate records and cultural sequences at Taforalt and El Harhoura 2 show that Middle Stone Age occupations of both sites occurred during relatively humid and arid climate phases. The transition to the Later Stone Age appears to have taken place during a period of increased aridity, hinting that this cultural transition may be related to changing environmental conditions.
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Seasonality and Ecosystem Response in Prehistoric Agricultural Regions of Central ArizonaJanuary 2011 (has links)
abstract: This thesis explores the independent effects of the manipulation of rocks into alignments, prehistoric farming, and season on soil properties in two areas with a history of prehistoric agriculture in central Arizona, Pueblo la Plata within the Agua Fria National Monument (AFNM), and an archaeological site north of the Phoenix basin along Cave Creek (CC). Soil properties, annual herbaceous biomass and the physical properties of alignments and surface soils were measured and compared across the landscape, specifically on: 1) agricultural rock alignments that were near the archaeological site 2) geologically formed rock alignments that were located 0.5-1 km away from settlements; and 3) areas both near and far from settlements where rock alignments were absent. At AFNM, relatively well-built rock alignments have altered soil properties and processes while less-intact alignments at CC have left few legacies. / Dissertation/Thesis / M.S. Biology 2011
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A survey of San paintings from the southern Natal DrakensbergSteynberg, Peter John January 1988 (has links)
From Introduction: The study of San rock art has undergone several different phases in approach to the interpretation of art. Two approaches are currently in use. The first emphasises the art as narrative or literal representations of San life and its proponents may be called the "art for art's sake" school. Adherents to the second approach make detailed use of the San ethnography on the belief system of these people and are highly critical of the literalists because they provide no such context. The second approach has rapidly gained ascendancy and replaced the "art for art's sake" school over the last twenty years. The watershed came with the researches of Vinnicombe (1967) in the southern Drakensberg and Maggs (1967) in the Western Cape who both embarked upon programs of research which had quantification and numerical analysis at their core, so that they could present "...some objective observations on a given sample of rock paintings in a particular area..." in order to compare and contrast paintings from geographically different areas. What Vinnicombe's numerical analyses clearly showed was that the eland was the most frequently depicted antelope and that it must have played a fundamental role "...in both the economy and the rellgious beliefs of the painters...", which opened up the search for what those beliefs might be and how they could be related to the rock art itself. In order to understand what the rock art was all about it was recognised that researchers had to meaningfully contextualise the art within the social and religious framework of the artists themselves. Without the provision of such a relevant context, as many different interpretations of the paintings could be made as there were people with imaginations. Such a piecemeal approach provides a meaningless jumble of subjective fancy which tells us something about the interpreters but nothing about the rock art. It is unfortunate that the advent of this explicitly social and anthropological approach marks the end of the amateur as a serious interpreter of San rock art, for the juxtaposition of the ethnography with the rock art requires a proper training in which the intricacies of symbol and metaphor can be recognised.
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Farma v jeskyni - divadlo laboratoř / Farm in the Cave--a Laboratory TheatreMogilnicka, Krystyna January 2015 (has links)
This thesis, entitled Farm in the Cave-a Laboratory Theatre, presents Viliam Dočolomanský's International Theatre Studio Farm in the Cave based in Prague, Czech Republic as an aspect of the discourse of 'laboratory theatres.' The first part examines the concept of the 'laboratory theatres' that developed in the 1960s as a new 'genre' of theatre practice and a 'method' of creating performances based on physical expression; this is presented as distinct from the 'theatre laboratories' that emerged at the beginning of the 20th century mostly in the framework of institutions as 'schools' for actors. As such, this thesis introduces the changes that came with Jerzy Grotowski's manifestos in connection to his easily adaptable training for actors and idea of 'physical scores.' Laboratory theatres' background and interests are presented as alternative theatre practice that emerged from a need of 'searching for truth' through the body what evolved into counterculture attitude. The first part establishes Eugenio Barba's Odin Teatret as an independent laboratory that developed on the margins of the contemporary theatre community and evolved into an influential culture institution. Odin Teatret's achievements in developing physical acting and original theatre directing are set in confrontation with the...
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Les miroirs imparfaits : une approche anthropologique de l’art rupestre / The imperfect mirrors : an anthropological perspective on rock artMonney, Julien 19 January 2015 (has links)
De toutes les questions qui agitèrent et agiteront encore pour longtemps le champ de la recherche en art rupestre, la plus fondamentale est sans doute celle de son sens ou, plus exactement, de la production de son sens. Comment, d’une manière générale, rendre compte de l’existence d’images rupestres sur les parois de certaines grottes d’Europe occidentale, mais aussi comment produire du sens quant aux conditions ayant prévalu à leur formation ? Partant des débats soulevés depuis près d’un siècle en archéologie préhistorique par l’usage de comptes-rendus ethnographiques afin d’interpréter l’art pariétal paléolithique européen, la thèse présentée ici ouvre sur une réflexion plus large quant à la nature des objets et des expériences qui sont employés en archéologie afin de rendre compte des événements du passé. Elle questionne ainsi : (a) la nature des comptes-rendus ethnographiques disponibles, dont un inventaire de 795 cas est présenté. Elle aborde aussi (b) les modes de construction des données archéologiques au travers de l’exemple des grottes ornées paléolithiques de la région Gard-Ardèche-Hérault. Elle interroge enfin (c) la place de la subjectivité dans le processus de création de connaissances sur le passé. A chaque fois, la nécessité d’un retour à l’individu est soulignée, que ce soit l’individu en tant que cas ethnographique (fruit d’une rencontre entre deux personnes), l’individu archéologique (l’entité rupestre) ou encore l’individu-chercheur en tant que sujet. Au travers d’une discussion quant au rapport au temps, à la notion de phénomène ou encore à l’altérité, cette thèse s’attache ainsi à analyser les implications d’une expression sur le passé et la création. / Among all the questions that have arisen in the field of rock art research, the most fundamental is probably the question of meaning, or more exactly the question of producing meaning. How to account for the existence of rock art on the walls of some caves of Western Europe, but also how to create meaning about the conditions in which those images were produced? Taking as a starting point the debates that have been going on for almost a century in prehistoric archaeology about the uses (and abuses) of ethnographic accounts to interpret European Palaeolithic cave art, this thesis opens up on a broader reflection on the nature of objects and experiences that are used in archaeology to account for past events. Thus, it questions (a) the nature of ethnographic data available, through a database of 795 ethnographic accounts linked with the production, the refection or the use of rock images worldwide. It also addresses (b) the ways of constructing archaeological data through the example of the palaeolithic rock art caves in the Gard-Ardèche-Hérault region (South-eastern France). Finally, it discusses (c) the role played by subjectivity in the process of creating knowledge about the past. Each time, the need for a return to the individual cases is emphasized: at an ethnographic level, the individuals consisting of first hand records resulting from the meeting between two different persons; at an archaeological level, single rock art images; and at a scientific level, the researcher himself. Through a discussion of the notions of time, phenomenon and alterity (otherness), this thesis attempts to analyze the implications of any expression dealing with the past and creation.
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Estudo da assembleia de quirópteros (Mammalia: Chiroptera) da Gruta do Riacho Subterrâneo – município de Itu – SPRocha, Alana Drielle 29 April 2015 (has links)
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Previous issue date: 2015-04-29 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / The objective of the present study was to analyze the taxonomic composition and structure
of a bat assemblage of Gruta do Riacho Subterrâneo, a granitic cave located the municipality
of Itu, São Paulo State, Brazil, and to verify the influence of abiotic variables on its structure.
The main hypotheses were: a) The cave studied is important to the regional diversity of bats
functioning as a shelter to some important bat species. b) There are changes in the
composition and abundance of the bat assemblages as a consequence of abiotics changes
observed in the studied area. Five samplings were carried out along the twelve months.The
captures were performed using mist nets and bats were measured and ringed. The catch
effort, relative abundances, the species acumulation curve and the influence of abiotic
variables on chiropterofauna were determined. The influence of abiotics variables were
analysed by multiple regression and canonic correspondence analysis, performed in the R
program. A total of 113 individuals were captured in the cave and its surrounding area, from
which more than 80% belonged to the family Phyllostomidae and the remaining to the
Vespertilionidae. The acumulation curve for the samples indicated that the assymptotic
portion of the curve was not reached. The most abundant species were Carollia perspicillata
(30,8%), Desmodus rotundus (29.%) and Myotis sp. (23.4%) whereas some other species as
Anoura geoffroyi, Micronycteris sp., Chiroderma doriae, Sturnira tildae and Eptesicus
diminutus had single events of capture. There was no significant relationship between the
abiotic variables measured and the community structure along the time, indicating that
probably other factors might be influencing the population dynamics. The cave community
has high species richness encompassing five important trophic guilds, particularly the
frugivorous one, revealing the importance of the Gruta do Riacho Subterrâneo cave for the
conservation opf local diversity. Based on the functional aspects of thisconservation and also
restauration of the cave surrounding area will be essential to diversity conservation for this
important group of mammals. / O objetivo do presente estudo foi investigar a composição e a estrutura da assembleia de
morcegos na Gruta do Riacho Subterrâneo uma caverna granítica localizada no município
de Itu, SP, bem como a influência de variáveis abióticas (temperatura, umidade relativa e
pluviosidade) sobre a mesma, As hipóteses foram: A caverna estudada possui grande
importância como abrigo para as espécies de morcegos da fauna regional e b): Existem
alterações na composição e na abundância das populações que compõem a assembleia de
morcegos analisada decorrentes de mudanças abióticas observáveis na área de estudo.
Foram realizadas cinco amostragens ao longo de doze meses. A captura foi feita por redes
de neblina e os morcegos foram mensurados e anilhados. Foram calculados o esforço de
captura, a curva de acumulação de espécies e a abundância relativa das espécies e
analisada a influência das variáveis abióticas sobre a quiropterofauna. Para avaliar a
influência das variáveis abióticas foram feitas uma regressão múltipla e uma
correspondência canônica, no programa R. Foram coletados 113 indivíduos na caverna e
em seu entorno, dos quais mais de 80% pertencem a família Phyllostomidae e o restante à
família Vespertilionidae. A curva de acumulação não atingiu o valor assintótico, sugerindo
que a riqueza de espécies deve ser maior. As espécies mais abundantes foram Carollia
perspicillata (30,8%), Desmodus rotundus (29,6%) e Myotis sp. (23,4%), enquanto algumas
outras espécies como Anoura geoffroyi, Micronycteris sp., Chiroderma doriae, Sturnira tildae
e Eptesicus diminutus tiveram eventos únicos de captura. As variáveis abióticas não
influenciaram significativamente a estrutura da comunidade ao longo dos meses, indicando
que outros fatores influenciam a dinâmica dessas populações. A assembleia de morcegos
analisada teve elevada riqueza de espécies, abrangeu cinco importantes guildas tróficas,
com destaque para a de frugívoros revelando a importância da caverna Gruta do Riacho
Subterrâneo para a conservação da diversidade local. Com base nos aspectos funcionais da
assembleia de morcegos, a conservação e recuperação da área de entorno será essencial
para a preservação da diversidade deste importante grupo de mamíferos.
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Návraty k přírodě / Returns to the natureDUŠKOVÁ, Lenka January 2012 (has links)
Returns to the nature In the theoretical part the work is focused on a short presentation of some important prehistoric monuments, and the visual impression which the artworks of our ancestors leave on a present man. It endeavour to do exoteric confrontation between prehistoric art and modern art. The image part of this work is based on "a game" individually-up to dated subjects and a hidden notation placed in the scenes, which are inspirated by our ancestors who were materialized in absolutely different conditions surroundings than we are.
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O uso de realidade virtual na manufatura da indústria de construção naval/offshoreEspíndola, Danúbia Bueno January 2007 (has links)
Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia Oceânica, Escola de Engenharia, 2007. / Submitted by Lilian M. Silva (lilianmadeirasilva@hotmail.com) on 2013-04-23T19:16:00Z
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Previous issue date: 2007 / Este trabalho propõe uma metodologia para visualização distribuída de plantas de manufatura. A metodologia considera o uso de um conjunto de ferramentas capazes de propiciar a visualização imersiva de cenários virtuais. Projetos CAD, modelos e simulações são obtidos através de ferramentas de manufatura digital utilizadas na indústria e podem ser visualizados neste experimento em um dispositivo tipo CAVE. A proposta é validada em um estudo de caso associado à Indústria Naval/Offshore. Inicialmente o estudo apresenta os conceitos sobre os Sistemas de Construção Naval e Offshore no cenário mundial e os Sistemas de Manufatura Digital utilizados para esses fins. Após, o trabalho focaliza a utilização da Realidade Virtual em processos industriais identificando os objetivos e desafios da implantação de uma metodologia para visualização imersiva distribuída. Por fim, são apresentados testes e resultados obtidos com a utilização da metodologia de solução proposta, validados através de
um estudo de caso realizado na Indústria Naval/Offshore. / This study proposes a methodology for immersive distributed visualization of Manufacturing Plants. A set of tools that make possible the immersive visualization of virtual sceneries for plant simulation are applied. CAD projects, models and simulations used in industry can be viewed in this experiment in device CAVE. The proposed ideas are then validated on a case
study associated with Shipbuilding and Offshore Industries. Initially the study present the concepts about Shipbuilding and Offshore Systems in the world scenery and Digital Manufacturing Systems that can be used. After this discussion, this study focus on industrial application of virtual reality for then to identify the objectives and challenges of the implantation of one methodology for immersive distributed visualization. Finally Tests and Results are presented for the proposed methodology solution that will be validated through the
study of a real case associated with Shipbuilding and Offshore Industries.
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La dynamique du carbone inorganique dans le continuum sol-épikarst-cavité du site de la Grotte de Lascaux (Dordogne, France) : apports des monitorings hydrogéochimique et microclimatique continus pour l’étude de l’aérologie et le développement d’une méthode de simulation des processus calco-carboniques aux parois / Inorganic carbon dynamics into the soil-epikarst-cavity continuum of the Lascaux Cave (Dordogne, France)Houillon, Nicolas 13 December 2016 (has links)
Depuis son invention en 1940 mais surtout consécutivement à sa fermeture au public en 1963, la conservation de la Grotte de Lascaux se base entre autres sur la compréhension de ses interactions avec le massif karstique environnant et notamment les processus siégeant dans l’épikarst et la zone de transmission superficielle. Ces travaux de thèse se sont donc attachés à comprendre la dynamique du CO2 dans le continuum sol-épikarst-cavité afin d’en évaluer les potentiels impacts sur la conservation des parois. Nous bénéficions à Lascaux d’une fenêtre d’observation sur les écoulements provenant de l’épikarst sus-jacent dans le SAS 1 de la cavité, mais aussi d’une instrumentation conséquente. Elle permet l’acquisition de nombreuses séries de données temporelles des paramètres microclimatiques ainsi que des teneurs en CO2 de l’air en différents points de la cavité ou encore du débit de l’émergence épikarstique depuis le début des années 2000.Une première partie de l’étude est consacrée à la caractérisation de la dynamique du CO2 dans le contexte d’un épikarst sous couverture pédologique. A cette fin, une parcelle expérimentale est instrumentée afin d’effectuer un suivi des paramètres hydroclimatiques et des teneurs en CO2 à différentes profondeurs. Des périodes de recharge (accumulation) et de vidange (émanations vers l’atmosphère) du CO2 de l’épikarst superficiel sont démontrées tout comme la constitution d’un stock de CO2 peu variable dans l’épikarst subsuperficiel. La compréhension de ces différents mécanismes aboutit à un schéma général de la dynamique du CO2 dans l’épikarst.Cette dynamique est étudiée dans la Grotte de Lascaux au cours d’une seconde partie à partir des séries temporelles des paramètres microclimatiques et des teneurs en CO2, mais aussi du signal isotopique en 13C. Il est alors démontré que les flux de CO2 entrant dans la cavité proviennent de trois origines distinctes : l’atmosphère (entrée), l’épikarst superficiel (Galerie Mondmilch et Salles Ensablées) et le massif (éboulis du Puits du Sorcier). Parallèlement, deux régimes aérologiques responsables de la répartition spatio-temporelle des teneurs en CO2 dans la cavité sont observés : stratification et thermoconvections. Ils sont les principaux responsables de la dynamique du CO2 dans la Grotte de Lascaux du fait des faibles échanges entre cette dernière et l’atmosphère comparativement à d’autres cavités karstiques de la région. Enfin, l’impact du dispositif du pompage de l’air sur l’aérologie et la dynamique du CO2 dans la Grotte de Lascaux est évalué. La comparaison de ces dynamiques avec et sans extraction de l’air de la cavité conduit à la création de schémas conceptuels de la dynamique du CO2 dans la Grotte Lascaux.L’étude des conditions d’écoulement dans l’épikarst de la Grotte de Lascaux, troisième partie de ces travaux, a été effectuée à partir d’un suivi en continu des débits, paramètres physico-chimiques et de la fluorescence naturelle de l’eau. L’analyse des séries temporelles de ces traceurs naturels conduit caractériser de façon détaillée les conditions d’écoulement et notamment l’importance de la teneur en eau de l’épikarst sur la taille zone d’alimentation et les types d’eau arrivant à l’exutoire. Parallèlement, l’impact de ces conditions d’écoulement sur les équilibres calco-carboniques des eaux arrivant dans la cavité est analysé.Enfin, les connaissances acquises sont appliquées pour déterminer l’impact potentiel en continu des eaux (condensation et exfiltration) présentes aux parois ornées de la cavité. A cette fin, une méthodologie d’estimation de la masse de calcite potentiellement précipitée par les eaux d’exfiltration et dissoute par les eaux de condensation basée sur des simulations hydrogéochimiques est développée. Son application à la paroi gauche de la Salle de la Taureaux en contextes de pompage et naturel conduit à l’évaluation de l’impact potentiel du pompage mais aussi de l’aérologie de la cavité sur la conservation des parois. / Since its invention in 1940 but especially as a result of its closure to the public in 1963, the preservation of the Cave of Lascaux bases itself among others on the understanding of its interactions with the surrounding karstic massif in particular the processes sitting in the épikarst and the zone of superficial transmission. That is why this thesis research attempted to understand the dynamics of the CO2 in the continuum soil-epikarst-cave to estimate the potential impacts on the preservation of walls. We benefit in Lascaux of an observation window on the flows resulting from the epikarst known emergence in the SAS 1 of the cavity, but also the consequent instrumentation. It allows the acquisition of numerous time series data of the microclimatic parameters, carbon dioxide partial pressures at different points of the cave and the discharge of the epikarstic emergence since the beginning of the century.A first part of the study is dedicated to the characterization of the dynamics of the CO2 in the context of an epikarst under soil cover. To this end, an experimental parcel is instrumented to follow the hydroclimatic parameters and the contents in PCO2 at various depths. Periods of recharge (accumulation) and draining (emanations towards the atmosphere) of the superficial epikarst CO2 are highlighted when the constitution of a low variable CO2 stock is observed in the subsuperficiel epikarst. The understanding of these various mechanisms ends in a conceptual scheme of the CO2 dynamics in the epikarst.In a second part, this dynamic is studied in the Cave of Lascaux from the temporal series of the microclimatic parameters and the contents in CO2, but also the δ13CCO2. It is then demonstrated that the flows of CO2 entering the cavity result from three different origins: the atmosphere (entrance), the superficial epikarst (Mondmilch Gallery and Silted-up Rooms) and the massif (screw of the Shaft of the Sorcerer). At the same time, two aerological regimes responsible for the spatiotemporal distribution of the PCO2 in the cavity are observed: stratification and thermoconvection. They are the main mechanisms responsible for the dynamics of the CO2 in the Cave of Lascaux because of the low exchanges with the atmosphere. Finally, the impact of the pumping of the air on the aerology and the dynamics of the CO2. The comparison of these dynamics with and without extraction of the air of the cavity leads to the creation of conceptual schemes of the dynamics of the CO2 in the Cave Lascaux.The study of the flowing conditions in the epikarst of the Cave of Lascaux, the third part of these works, was made from a continuous monitoring of the discharge, physico-chemical parameters and the natural fluorescence of the water. The analysis of the temporal series of these natural tracers leads to characterize in a detailed way the flowing conditions and the importance of the moisture content of the epikarst on the size of the recharge area and the types of water arriving at the emergence. In parallel, the impact of these conditions on the calco-carbonic balances of waters arriving in the cavity is analyzed.Finally, the acquired knowledge are applied to determine the potential continuous impact of the waters (condensation and exfiltration) present at the adorned walls of the cave. To this end, a methodology of estimation of the mass of calcite potentially precipitated by exfiltration and dissolved by condensation based on hydrogeochemical simulations is developed. Its application to the left wall of the Hall of the Bulls with and without pumping leads to the evaluation of the potential impact of this device but also the aerology of the cavity on the preservation of walls.
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