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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.
11

The carbon isotope signature of fossil phytoliths : the dynamics of C [subscript 3], and C [subscript 4] grasses in the Neogene /

Smith, Francesca Avril. January 2002 (has links)
Thesis (Ph. D.)--University of Chicago, Department of the Geophysical Sciences, 2002. / Includes bibliographical references. Also available on the Internet.
12

Reconstructing Historical Vegetation Cover in Otago, New Zealand, Using Multi-proxy Analysis of Peat Cores.

Taylor, Sam January 2010 (has links)
This research has examined the historical vegetation of two Eastern Otago sites below the regional treeline, with the aim of addressing questions about the distribution and spread of native tussock grasslands prior to human arrival in New Zealand c. 800 yr BP. Pollen and phytolith (plant opaline silicate) proxies have been extracted from peat cores at Swampy Summit and Clarks Junction to provide a record of vegetation spanning the Holocene. Using multiple proxies and two sample sites has allowed for comparisons of the record of vegetation from within sites and between sites. A record of the modern pollen rain was also gathered from localised moss polsters at Swampy Summit in order to reconcile modern pollen assemblages and transport patterns with historical findings. It became clear from the research that the record of vegetation inferred from phytoliths was not analogous to the pollen-based records, which supported the hypothesis that vegetation reconstructions based solely on pollen may be unreliable. Good pollen preservation in the sediments allowed for the identification of over 50 taxa, although only Chionochloid forms were identifiable to a family level in the phytolith records. Poaceae pollen was abundant throughout the Clarks Junction record, suggesting grassland had persisted at this site during the Holocene, while Poaceae pollen at Swampy Summit was minimal and sporadic. Phytoliths at Swampy Summit show grasses have persisted at the site thoughout the Holocene, at times in much greater proportions than the pollen record would suggest, while Chionochloid phytoliths only become common near the top of the record, possibly reflecting increasing dominance of this taxa after human disturbance. In contrast to Swampy Summit, the Clarks Junction phytolith record reflects a more stable presence of grasses throughout the Holocene, with Chionochloid forms present throughout. Phytoliths appear to be a more reliable proxy for local vegetation, with both sites indicating a Holocene presence of grasses below the regional treeline prior to human arrival in New Zealand. In comparison, the pollen record appears to indicate a more regional pattern of vegetation, with the grassland pollen record complicated by pollen dispersal and deposition factors.
13

The application of phytolith and starch grain analysis to understanding formative period subsistence, ritual, and trade on the Taraco Pennisula, Highland Bolivia

Logan, Amanda Lee. January 2006 (has links)
Thesis (M.A.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 21, 2009) Includes bibliographical references.
14

The prehistory of Madagascar : microbotanical and archaeological evidence from coastal and highland sites

Pomerantz, Solomon January 2017 (has links)
Despite nearly one hundred years of archaeological and palaeoecological research in Madagascar, the human colonisation of the island remains poorly understood. Long- standing narratives of this colonisation described the arrival of Austronesian- speaking peoples by AD 400, eventually reaching the Central Highlands by the 12th century. The recent discovery of microlithic tools at the rockshelter of Lakaton'i Anja has radically disrupted conventional narratives for this colonisation by more than doubling the known period of Madagascar's human history, and questioning the presumed Austronesian origins of these first Malagasy peoples. This discovery also challenges existing models for the late Holocene extinction of the island's megafauna. This thesis constitutes the first systematic review in the last thirty years of literature relating to the colonisation of the island, as well as the first to approach this multidisciplinary material in light of new archaeological evidence from Lakaton'i Anja. This study also represents the first comprehensive and comparative phytolith analysis conducted on Madagascar. Despite the wide application of phytolith analysis across regional archaeological and palaeoecological contexts, it has never before been applied here. This thesis explores the botanical impact of these early colonists in and around sites of occupation, as well as tracing the introduction of Asian rice (Oryza sativa) and domesticated bananas (Musa acuminata). New methods of phytolith analysis were developed, adapted, and applied to sediments collected from two seasons of excavations in 2012 and 2013. The sites of Lakaton'i Anja, Mahilaka, and Ankadivory D'Ralambo were re-excavated, as well as the new site of Ampasimahavelona, near Vohémar. This thesis presents and discusses these excavations as well as the earliest evidence for the cultivation of both Musa acuminata and Oryza sativa on Madagascar, and an ultra-high resolution botanical perspective on the last four millennia of Madagascar's prehistory.
15

Sistemas pedológicos e reconstituição paleoambiental em depressões nos Tabuleiros Costeiros do Extremo Sul da Bahia / Pedological systems and paleoenvironmental reconstruction in depressions in the Coastal Tablelands of the Extreme South of Bahia

Pereira, Wander Murilo Alves 25 April 2019 (has links)
A ocorrência de depressões fechadas, sistemas endorréicos superficiais, tem sido citada em várias partes do mundo. Nos Tabuleiros Costeiros do Brasil, onde também pode ser observada a presença destas depressões, estas feições geomórficas são conhecidas pela denominação de muçununga e/ou campos nativos ou simplesmente nativos. São consideradas enclaves de vegetação savânica em meio à Floresta Ombrófila Densa de Terras Baixas do Bioma Mata Atlântica, variando desde formações graminóides até florestadas. Além de representarem importantes áreas para o estudo da reconstituição paleoambiental, possuem drenagem centrípeta, o que faz com que os materiais advindos do solo circundante fiquem armazenados na depressão, gerando importantes arquivos de proxies ambientais. A área em estudo situa-se no município de Prado - BA no Parque Nacional do Descobrimento, em meio à Mata Atlântica em bom estado de conservação. Foram estudadas duas depressões, uma com regime hídrico hiper concentrador e outra com regime hídrico concentrador. Desse modo, este trabalho tem como objetivo, relacionar os conteúdos fitolíticos e isotópicos dos solos do topo e da base da catena de duas depressões com a reconstituição paleoambiental. Foram realizadas análises fitolíticas, isotópicas e datação por LOE, bem como análises granulométrica e químicas para caracterização dos solos. O sistema pedológico dominante nas duas muçunungas estudadas é de Argissolo Amarelo-Espodossolo-Organossolo com clara influência da drenagem na expressão dos organossolos. Na escala da paisagem, observou-se haver um alinhamento preferencial das depressões, tendo o seu início mais ligado a neotectônica do que ao clima, a partir de um ajuste estrutural, inicialmente seguindo a disposição de falhas e fraturas geológicas. Apesar da vegetação atual nas duas depressões ser de porte graminóide a arbustivo (savânica), diferentes das áreas florestadas ao entorno, os resultados isotópicos apresentaram valores de δ13C acima de -27,73‰, padrão para plantas de ciclo fitossintético C3, o que comparando com os resultados de δ15N, C/N e fitolíticos, mostraram em profundidade condições menos hidromórficas que as atuais, demonstrando que nestes locais eram ocupados antes por florestas, sugerindo que estas depressões estão em processo de expansão. / The occurrence of closed depressions, superficial endorheic systems, has been reported in several parts of the world. In the Coastal Tablelands of Brazil, where the presence of these depressions can also be observed, these geomorphic features are known by the name of muçununga and/or native or simply native fields. They are considered enclaves of savanna vegetation in the middle of the Dense Ombrophilous Lowland Forest of the Atlantic Forest Biome, varying from graminoid to forested formations. Besides representing important areas for the study of paleoenvironmental reconstruction, they have centripetal drainage, which causes that the materials coming from the surrounding soil are stored in the depression, generating important files of environmental proxies. The study area is located in the municipality of Prado - BA in the National Park of Discovery, in the middle of the Atlantic Forest in good condition. Two depressions were studied, one with a hyper concentrating water regime and the other with a concentrating water regime. In this way, this work aims to relate the phytolytic and isotopic contents of the soils of the top and the base of the catena of two depressions with the paleoenvironmental reconstitution. Phytolytic, isotopic and LOE dating, as well as granulometric and chemical analyzes for soil characterization were performed. The dominant pedological system in the two studied muçunungas is of Argissolo Amarelo-Espodossolo-Organossolo with clear influence of the drainage in the expression of the Organosolos. In the landscape scale, there was a preferential alignment of the depressions, whose beginning was more connected to neotectonics than to the climate, starting from a structural adjustment, initially following the arrangement of faults and geological fractures. Although the present vegetation in the two depressions is of graminoid to shrub (savanna), different from the forested areas to the surroundings, the isotopic results presented values of δ13C acima de -27,73‰, standard for plants of C3 phytosynthetic cycle, which comparing with the results of δ15N, C / N and phytolithic, showed in depth less hygromorphic codings than the present ones, demonstrating that in these places they were previously occupied by forests, suggesting that these depressions are in the process of expansion.
16

Microfósseis contidos no cálculo dentário como evidência do uso de recursos vegetais nos sambaquis de Jabuticabeira II (SC) e Moraes (SP) / Microfossils from the dental calculus as evidence of plant use in Brazilian Shellmounds: Jabuticabeira II (SC) and Moraes (SP)

Boyadjian, Célia Helena Cezar 06 December 2007 (has links)
A análise de microfósseis vegetais é extremamente útil para a recuperação de informações acerca da utilização de plantas por grupo humanos do passado, especialmente em sítios arqueológicos em que os macro-restos botânicos são raros, como é o caso dos sambaquis. Estes micro-restos podem ser obtidos a partir de sedimento, coprólitos, utensílios de pedra ou cerâmica, assim como de cálculo dentário (tártaro). Durante a mastigação e a utilização dos dentes como ferramentas, micro partículas provenientes do alimento ou da matéria prima utilizada, como grãos de amido, fitólitos, fibras, ficam retidas na matriz do cálculo, podendo ali permanecer protegidas por milhares de anos. O tratamento químico do cálculo permite a recuperação destes microfósseis, que, uma vez quantificados e identificados, fornecem dados valiosos para a reconstrução de hábitos e dieta. Entretanto, existem sítios em que, além da má preservação dos macro-restos vegetais, restam apenas escassas marcas de cálculo dentário aderidos aos dentes, impedindo a obtenção de fragmentos de cálculo e conseqüentemente a recuperação dos microfósseis. A utilização de recursos vegetais pelos grupos construtores de sambaquis constitui uma área do conhecimento ainda pouco explorada. Dentre os sambaquieiros há aqueles com depósitos fartos de cálculo dentário, como é o caso em Jabuticabeira II (SC), mas também há aqueles que apresentam somente reduzidos depósitos de cálculo, como é o caso em Moraes (SP). Assim, os objetivos deste trabalho foram: processar e analisar quantitativamente o conteúdo do cálculo dentário de indivíduos de Jabuticabeira II; desenvolver e testar um método alternativo que permitisse a recuperação de microfósseis a partir de marcas de cálculo dentário (.dental wash.); aplicar este método alternativo nos indivíduos de Moraes e comparar os resultados obtidos entre os dois sítios. Através dos resultados obtidos concluiu-se que: - O método .dental wash. é eficiente para a recuperação de micro partículas a partir de marcas exíguas de cálculo dentário, e seus resultados são comparáveis àqueles obtidos através da técnica tradicional. Contudo, o .dental wash. pode tornar os dentes mais friáveis, prejudicando análises morfológicas e de microdesgaste. - Foram observados grãos de amido em praticamente todas as amostras de Jabuticabeira II e Moraes, enquanto fitólitos somente foram encontrados em poucas delas. Isso indica um importante aporte de alimento amiláceo em ambos os sítios, enquanto que apenas 134 alguns indivíduos consumiam uma dieta mais diversificada, constituída em parte de vegetais ricos em fitólitos. - Grãos de amido modificados (em ambos os sítios) e fragmentos escuros de origem vegetal (somente em Jabuticabeira II) indicam o preparo de alimentos através de cocção, maceração, abrasão. - A concentração média dos grãos de amido significativamente maior nas amostras de Moraes em comparação com Jabuticabeira II sugere que o aporte amiláceo tivesse sido maior em Moraes, o que é confirmado indiretamente através da maior freqüência de cáries. -Não parece ter havido distinção no aporte vegetal da dieta entre os sexos, já que não houve diferença das concentrações de amido e fitólitos entre homens e mulheres de Jabuticabeira II e Moraes. / The analysis of vegetal microfossils is paramount for the recovery of informations about plant use in past human groups, especially in archaeological contexts where macro remains are poorly preserved (as in shellmounds or sambaquis). Micro remains can be recovered from sediments, coprolites, stone artefacts, pottery, as well as from dental calculus. During the mastication and the use of the teeth as tools, micro particles like starch grains, phytoliths and fibers, become trapped in the dental calculus matrix. Chemical processing of dental calculus permits the extraction of microfossils. Quantification and identification allows reconstruction of habits and diet of past human groups. However, there are sites in which the calculus deposits do not preserve well enough to be processed using the traditional method. The plant use by Brazilian shellmound groups is still an underexplored matter. Among these there are groups like Jabuticabeira II (SC) with large deposits of dental calculus, where the traditional method can be applied, as well as others with just faint dental calculus marks, like Moraes (SP). Therefore, the aims of this work are to: process and analyse dental calculus contents from Jabuticabeira II individuals; develop and test a new method for the recovery of microfossils form cryptic dental calculus marks (dental wash); apply the dental wash in Moraes teeth; and, finally, to compare the results between both sites. The data obtained permit the following conclusions: -The dental wash technique is efficient for the recovery of microfossils from faint dental calculus marks and the results are comparable to those obtained by the traditional method. However, dental wash can preclude morphological and microwear analyses. - Starch grains were observed in almost all samples from both sites but the phytoliths were obtained only from few of them. This indicates that the vegetal diet in these sites was based mainly in storage organs of plants where only few individuals had a more diverse food intake, consuming also vegetal parts rich in phytoliths. - Modified starch grains found in both sites and dark plant fragments (charcoal) found only in Jabuticabeira II suggest food preparation. - The significant higher concentrations of starch grains in Moraes than in Jabuticabeira II, suggests that the intake of carbohydrate rich food was higher in Moraes. Indeed, this is corroborated by a much higher caries rates in the latter site. 136 -The absence of differences of starch and phytolith concentrations between men and women suggest that there was no distinction in the plant food consumed between the sexes.
17

Microfósseis contidos no cálculo dentário como evidência do uso de recursos vegetais nos sambaquis de Jabuticabeira II (SC) e Moraes (SP) / Microfossils from the dental calculus as evidence of plant use in Brazilian Shellmounds: Jabuticabeira II (SC) and Moraes (SP)

Célia Helena Cezar Boyadjian 06 December 2007 (has links)
A análise de microfósseis vegetais é extremamente útil para a recuperação de informações acerca da utilização de plantas por grupo humanos do passado, especialmente em sítios arqueológicos em que os macro-restos botânicos são raros, como é o caso dos sambaquis. Estes micro-restos podem ser obtidos a partir de sedimento, coprólitos, utensílios de pedra ou cerâmica, assim como de cálculo dentário (tártaro). Durante a mastigação e a utilização dos dentes como ferramentas, micro partículas provenientes do alimento ou da matéria prima utilizada, como grãos de amido, fitólitos, fibras, ficam retidas na matriz do cálculo, podendo ali permanecer protegidas por milhares de anos. O tratamento químico do cálculo permite a recuperação destes microfósseis, que, uma vez quantificados e identificados, fornecem dados valiosos para a reconstrução de hábitos e dieta. Entretanto, existem sítios em que, além da má preservação dos macro-restos vegetais, restam apenas escassas marcas de cálculo dentário aderidos aos dentes, impedindo a obtenção de fragmentos de cálculo e conseqüentemente a recuperação dos microfósseis. A utilização de recursos vegetais pelos grupos construtores de sambaquis constitui uma área do conhecimento ainda pouco explorada. Dentre os sambaquieiros há aqueles com depósitos fartos de cálculo dentário, como é o caso em Jabuticabeira II (SC), mas também há aqueles que apresentam somente reduzidos depósitos de cálculo, como é o caso em Moraes (SP). Assim, os objetivos deste trabalho foram: processar e analisar quantitativamente o conteúdo do cálculo dentário de indivíduos de Jabuticabeira II; desenvolver e testar um método alternativo que permitisse a recuperação de microfósseis a partir de marcas de cálculo dentário (.dental wash.); aplicar este método alternativo nos indivíduos de Moraes e comparar os resultados obtidos entre os dois sítios. Através dos resultados obtidos concluiu-se que: - O método .dental wash. é eficiente para a recuperação de micro partículas a partir de marcas exíguas de cálculo dentário, e seus resultados são comparáveis àqueles obtidos através da técnica tradicional. Contudo, o .dental wash. pode tornar os dentes mais friáveis, prejudicando análises morfológicas e de microdesgaste. - Foram observados grãos de amido em praticamente todas as amostras de Jabuticabeira II e Moraes, enquanto fitólitos somente foram encontrados em poucas delas. Isso indica um importante aporte de alimento amiláceo em ambos os sítios, enquanto que apenas 134 alguns indivíduos consumiam uma dieta mais diversificada, constituída em parte de vegetais ricos em fitólitos. - Grãos de amido modificados (em ambos os sítios) e fragmentos escuros de origem vegetal (somente em Jabuticabeira II) indicam o preparo de alimentos através de cocção, maceração, abrasão. - A concentração média dos grãos de amido significativamente maior nas amostras de Moraes em comparação com Jabuticabeira II sugere que o aporte amiláceo tivesse sido maior em Moraes, o que é confirmado indiretamente através da maior freqüência de cáries. -Não parece ter havido distinção no aporte vegetal da dieta entre os sexos, já que não houve diferença das concentrações de amido e fitólitos entre homens e mulheres de Jabuticabeira II e Moraes. / The analysis of vegetal microfossils is paramount for the recovery of informations about plant use in past human groups, especially in archaeological contexts where macro remains are poorly preserved (as in shellmounds or sambaquis). Micro remains can be recovered from sediments, coprolites, stone artefacts, pottery, as well as from dental calculus. During the mastication and the use of the teeth as tools, micro particles like starch grains, phytoliths and fibers, become trapped in the dental calculus matrix. Chemical processing of dental calculus permits the extraction of microfossils. Quantification and identification allows reconstruction of habits and diet of past human groups. However, there are sites in which the calculus deposits do not preserve well enough to be processed using the traditional method. The plant use by Brazilian shellmound groups is still an underexplored matter. Among these there are groups like Jabuticabeira II (SC) with large deposits of dental calculus, where the traditional method can be applied, as well as others with just faint dental calculus marks, like Moraes (SP). Therefore, the aims of this work are to: process and analyse dental calculus contents from Jabuticabeira II individuals; develop and test a new method for the recovery of microfossils form cryptic dental calculus marks (dental wash); apply the dental wash in Moraes teeth; and, finally, to compare the results between both sites. The data obtained permit the following conclusions: -The dental wash technique is efficient for the recovery of microfossils from faint dental calculus marks and the results are comparable to those obtained by the traditional method. However, dental wash can preclude morphological and microwear analyses. - Starch grains were observed in almost all samples from both sites but the phytoliths were obtained only from few of them. This indicates that the vegetal diet in these sites was based mainly in storage organs of plants where only few individuals had a more diverse food intake, consuming also vegetal parts rich in phytoliths. - Modified starch grains found in both sites and dark plant fragments (charcoal) found only in Jabuticabeira II suggest food preparation. - The significant higher concentrations of starch grains in Moraes than in Jabuticabeira II, suggests that the intake of carbohydrate rich food was higher in Moraes. Indeed, this is corroborated by a much higher caries rates in the latter site. 136 -The absence of differences of starch and phytolith concentrations between men and women suggest that there was no distinction in the plant food consumed between the sexes.
18

An early to middle Holocene carbon isotope and phytolith record from the Sac Valley Archaeological District, southwest Missouri

Rocheford, Mary Kathryn. Bettis, Elmer A. January 2009 (has links)
Thesis supervisor: E. Arthur Bettis, III. Includes bibliographic references (p. 102-107).
19

Prehispanic Maya foodways: archaeological and microbotanical evidence from Escalera al Cielo, Yucatan, Mexico

Simms, Stephanie Renee 22 January 2016 (has links)
Maize is universally considered to be the basis of prehispanic Maya foodways and maize-beans-squash agriculture the primary means of food acquisition. This narrow view is attributable to a lack of direct evidence and an oversimplification of the ethnographic data. In this dissertation I employ new methods to recover evidence of ancient plant foods at Escalera al Cielo (EAC)—a Terminal Classic (A.D. 800-950) Puuc Maya settlement located in Yucatán, Mexico—and challenge the notion that all Maya everywhere ate an unvarying diet of agricultural staples. By highlighting the tremendous variety of environments, foods, and food practices as well as the potential biases contained within the ethnohistorical and ethnographic literature, I use the archaeological evidence to reevaluate established models and explore daily food practices at EAC. The research focuses on domestic spaces from three excavated households, the artifacts that formed part of the culinary toolkit (e.g., ceramic vessels, grinding stones, chipped stone tools, and fired clay balls), and microbotanical residues (phytoliths and starch) associated with these spaces and artifacts. Modal analyses of artifacts and identifications of their residues permit testing of functional assumptions about culinary implements (e.g., "maize grinding stones"). The results reveal that most implements were multifunctional and that the food prepared and consumed at EAC included a range of cultivated and wild resources in addition to the expected staple ingredients of maize, beans, and multiple varieties of squash. There are also abundant starch residues from chile peppers (ground for seasonings and salsas), palm phytoliths that may represent foodstuffs, and at least three root crops—arrowroot, manioc, and Zamia sp.—the first of which may have been an additional staple ingredient. These new data illuminate regional food preferences, techniques of preparation, the diversity of food production and procurement strategies, symbolic associations of certain foods (identified in ritual contexts), and the skill and labor required of women who are widely considered to have been responsible for most food practices.
20

Establishing incidences of dental calculus and associated plant microfossils on South African plio-pleistocene hominin dentition

Odes, Edward John 08 January 2014 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science. Johannesburg, 2013. / Recent studies of the dental remains from Malapa, a fossil-bearing karstic cave-site located in the Cradle of Humankind (Berger et al., 2010), have demonstrated the presence of dental calculus and associated plant material in the form of phytoliths, preserved on the teeth of Australopithecus sediba (MH1) (Henry et al., 2012). This discovery raised the probability that dental calculus and plant microremains may also be present on hominin material from other cave sites in southern Africa, where fossils are preserved under similar conditions. The aim of this study was to establish the presence of dental calculus and associated microfossils on the teeth of other southern African Plio-Pleistocene early hominins. The dental collection of the Plio-Pleistocene age hominin site of Sterkfontein was examined. Where fossils were observed with adherent material, several analyses were performed to determine whether this material was calculus or not. Where possible, comparisons with the texture of the sediment matrix surrounding the fossil were conducted. Small quantities of this material were removed and observed microscopically to determine if it included food particulates and microfossils. In these cases, we also looked for microfossils in the surrounding matrix as a control. Phytoliths were recovered from all tooth sample material tested. The establishment of phytoliths in the dental calculus is direct evidence that these two structures existed simultaneously, as the formation of calculus can only take place in the presence of saliva. A large number of phytolith morphotypes further indicated that A.africanus had an adaptable and diverse diet, and that monocotyledons and dicotyledons appear to have made up a considerable part of their diet. The results from this study will benefit future analyses, by not only providing new protocols for establishing the presence of dental calculus, but also for promoting better preservation of dental calculus in the future. Further, future studies may be able to obtain direct evidence of consumed food that can directly be associated with individual hominins’ feeding behaviours. This could result in significant clues to the diet and ecology of not only individual hominins, but populations, species and comparisons of diet and behaviour between species and genera.

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