Spelling suggestions: "subject:"phytolith"" "subject:"phytoliths""
11 |
Análise da assembleia fitolítica do solo aplicada no holoceno médio: caso da Estação Ecológica da Mata Preta - Abelardo Luz (SC) / Analysis of soil phytolith assemblage applied to the middle-holocene: case of the Mata Preta Ecological Station - Abelardo Luz (SC)Ewald, Paula Louíse de Lima Felipe 02 June 2015 (has links)
Made available in DSpace on 2017-07-10T17:30:42Z (GMT). No. of bitstreams: 1
Paula_Ewald.pdf: 4676802 bytes, checksum: c77cee71420720dcbe5dd9d247b3cb6a (MD5)
Previous issue date: 2015-06-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In the Quaternary period, the south of Brazil has suffered from paleoclimate instabilities which have generated changes in the landscape. Pedological, sedimentological and paleoenvironmental reconstructions studies have been developed by the group Gênese e Evolução de Superfícies Geomórficas e Formações Superficiais - UNIOESTE-FB to investigate the paleoclimate influence on the landscape setting of the Southwest region in Paraná and Northwest region in Santa Catarina States. Aiming to contribute with these studies, this research has sought to investigate the evolution of the vegetation at Ecological Station Mata Preta in Abelardo Luz (Santa Catarina State) and to verify the hypothesis of occurrence of vegetation changes over the Holocene in the studied area. Specifically, the goal was to determine the phytolith signature of the current vegetation and to assess its variability in the superficial soil horizons under the Mixed Ombrophylous Forest (FOM - Araucaria Forest) and to know the historical trajectory of the changes in the vegetation of the area of study during the Holocene Era. Routine physical and chemical analyses have been used to characterize a soil profile and phytolith and isotopic analyses (δ13C of the soil organic matter - SOM and datation14Cof humin fraction) in a soil profile (Profile 1) and more three Control Points (PC1, PC2 and PC3). The physical and chemical analyses of the soil allowed the classification of the studied soil as a Humic Dystrophic Inceptisol. The values of δ13C of the SOMpointed to a vegetation change between the Middle Holecene and the Late and the phytolith assembly of the soil allowed the refining of this interpretation. Thus, it is possible to infer that his soil registers a period during which the vegetation was formed by a prevailing community of C4plants (more open than the current one), in the Middle/Early Holocene (6.235-6.215 years Cal. AP), evolving to a mixed vegetation, more forested and similar to the current one, composed, predominantly, of C3plants, in the Late Holocene (from 840 to 835 years cal. A.P.) which evolved to the current FOM. Based on the litterphytolith assemblage and on the superficial layers of the Inceptisol and the PC´s, it has been defined the phytolith signature of the FOM, which is formed by 14 morphotypes of phytoliths which represent the families of Poaceae (subfamilies Panicoid; Pooid; Chloridoid and Bambusoid), Eudicotiledoneae, Arecaceae and Cyperaceae. / No período Quaternário, o Sul do Brasil passou por instabilidades paleoclimáticas que geraram mudanças nas paisagens. Estudos pedológicos, sedimentológicos e de reconstrução paleoambiental têm sido desenvolvidos pelo grupo Gênese e Evolução de Superfícies Geomórficas e Formações Superficiais (UNIOESTE-FB) para investigar a influência paleoclimática na configuração da paisagem do Sudoeste do Paraná e Noroeste de Santa Catarina. Visando contribuir com estes estudos, a presente pesquisa buscou investigar a evolução da vegetação na Estação Ecológica Mata Preta em Abelardo Luz (SC) e verificar a hipótese de ocorrência de trocas de vegetação ao longo do Holoceno na a área estudada. Especificamente, objetivou-se determinar a assinatura fitolítica da vegetação atual e avaliar a sua variabilidade nos horizontes superficiais do solo sob a Floresta Ombrófila Mista FOM (Mata de Araucária) e conhecer a trajetória histórica das mudanças da vegetação da área de estudo durante a Época Holocênica. Foram empregadas análises físicas e químicas de rotina para caracterização de um perfil de solo e análises fitolíticase isotópicas (δ13C da matéria orgânica do solo e datação 14C da fração humina) em um perfil de solo (Perfil 1) e em três Pontos de Controle (PC1, PC2 e PC3). As análises físicas e químicas do solo permitiram classificar o solo estudado como um CAMBISSOLO HÚMICO. Os valores de δ13C da matéria orgânica do solo (MOS) apontaram para uma troca de vegetação entre o Holoceno Médio e o Superior e a assembleia fitolítica do solo permitiu o refinamento dessa interpretação. Assim é possível inferir que este solo registra uma fase em que a vegetação era formada por uma comunidade predominantemente de plantas C4 (vegetação mais aberta que a atual), no Holoceno Médio/Inferior (6.235-6.215 anos Cal. AP), evoluindo para uma vegetação mista, mais florestada e semelhante à atual, composta predominantemente por plantas C3 no Holoceno Superior (de 840 e 835 anos cal. A.P) que evoluiu para a atual FOM. Com base na assembleia fitolítica da serrapilheira e das camadas superficiais do Perfil de CAMBISSOLO e dos PC, definiu-se a assinatura fitolítica da FOM, que é formada por 14 morfotipos de fitólitos representativos das famílias Poaceae (subfamílias Panicoid; Pooid; Chloridoid e Bambusoid), Eudicotiledoneae, Arecaceae e Cyperaceae.
|
12 |
Les phytolithes, marqueurs des environnements mio-pliocènes du Tchad. Reconstitution à partir du signal environnemental des phytolithes dans l'Afrique subsaharienne actuelle / Phytoliths, indicators of the Mio-Pliocene environments of Chad. Paleoenvironmental reconstruction from the modern Sub-Saharan phytolith signal in AfricaNovello, Alice 06 December 2012 (has links)
Ce mémoire présente l'étude du signal phytolithique de sédiments mio-pliocènes du Tchad(Afrique Centrale) datés entre 7-2 Ma, et contemporains des Homininés anciens Sahelanthropustchadensis et Australopithecus bahrelghazali. Une calibration de la relation plantes-phytolithes-solspour l'Afrique tropicale subsaharienne actuelle a d'abord été réalisée pour apprécier la signatureenvironnementale des phytolithes dans le registre fossile. L'analyse des assemblages phytolithiques de98 espèces de graminées (Poaceae) a permis d'élaborer trois nouveaux indices phytolithiques à partirde 43 types propres aux Poaceae. Testés sur une base de 57 sols/sédiments modernes du Tchad, cesindices permettent de tracer les associations graminéennes aquatiques du Lac Tchad, les associationsmésophytiques des milieux humides soudaniens, et les associations xérophytiques des milieux secssahéliens. L'analyse des assemblages phytolithiques des sols/sédiments actuels considérés dans leurensemble a permis d'évaluer le potentiel de ce proxy à caractériser la physionomie des formationssoudano-sahéliennes modernes. La calibration a été appliquée à l'étude d'un enregistrementsédimentaire discontinu du Lac Tchad (6-2 Ma) (forage de Bol, 13°N/14°E) et à celle de 18 niveauxpaléontologiques du Djourab (7-3.5 Ma) (16°N/17°E). Les résultats indiquent la présence de savanesintermédiaires à fermées et de zones de végétation aquatique dominantes à 7 Ma dans le Djourab, puisde savanes plus ouvertes et sèches à 3.5 Ma. Une phase de bas niveau lacustre est enregistrée entre3.6-2.8 Ma à Bol, et un pic d'aridité à 3.2 Ma. Enfin, les résultats montrent l'existence de graminéesen C4 au Tchad depuis 7 Ma. / This thesis dissertation is dedicated to the study of the phytolith signal of Mio-Pliocenesediments from Chad (Central Africa) dated between 7-2 Ma, and contemporary to the early Homininspecies Sahelanthropus tchadensis and Australopithecus bahrelghazali. A calibration work studyingthe relationship plants-phytoliths-soils in modern sub-Saharan tropical Africa was carried out in orderto assess the environmental significance of the phytolith signal in the fossil record. Phytolithassemblages produced by 98 sub-Saharan grass species (Poaceae) were analyzed and the results led tothe development of three new phytolith indices defined from 43 types specific to Poaceae. Tested on adatabase of 57 modern soil/sediment samples from Chad, these indices allow drawing aquatic grassassociations of Lake Chad, mesophytic grass associations of wetlands from the Sudanian domain, andxerophytic grass associations of drylands from the Sahelian domain. The analysis of modern soilphytolith assemblages (total assemblages) was used to assess the potential of this proxy to characterizethe physiognomy of the Sudano-Sahelian vegetation types. The calibration had been applied to thestudy of a discontinuous sedimentary record from Lake Chad (6-2 Ma) (Bol core, 13°N/14°E) and of18 paleontological levels from the Djourab (7-3.5 Ma) (16°N/17°E). The results indicate thedominance of intermediate to closed savannas and areas of aquatic vegetation at 7 Ma in the Djourab,and more open and dry savannas at 3.5 Ma. A limited lacustrine stage is recorded between 3.6-2.8 Maat Bol, and a shift of aridity at 3.2 Ma. Finally, the results show the existence of C4 grasses in Chadsince 7 Ma.
|
13 |
Dental microwear texture analysis correlations in guinea pigs (Cavia porcellus) and sheep (Ovis aries) suggest that dental microwear texture signal consistency is species-specificMartin, Louise Francoise, Winkler, Daniela Eileen, Ackermans, Nicole Lauren, Müller, Jaqueline, Tütken, Thomas, Kaiser, Thomas, Codron, Daryl, Schulz-Kornas, Ellen, Hatt, Jean-Michel, Clauss, Marcus 28 November 2023 (has links)
Dental microwear texture (DMT) analysis is used to differentiate abrasive
dental wear patterns in many species fed different diets. Because DMT
parameters all describe the same surface, they are expected to correlate with
each other distinctively. Here, we explore the data range of, and correlations
between, DMT parameters to increase the understanding of how this group
of proxies records wear within and across species. The analysis was based
on subsets of previously published DMT analyses in guinea pigs, sheep,
and rabbits fed either a natural whole plant diet (lucerne, grass, bamboo)
or pelleted diets with or without added quartz abrasives (guinea pigs and
rabbits: up to 45 days, sheep: 17 months). The normalized DMT parameter
range (P4: 0.69 0.25; M2: 0.83 0.16) and correlation coefficients (P4:
0.50 0.31; M2: 0.63 0.31) increased along the tooth row in guinea pigs,
suggesting that strong correlations may be partially explained by data range.
A comparison between sheep and guinea pigs revealed a higher DMT data
range in sheep (0.93 0.16; guinea pigs: 0.47 0.29), but this did not
translate into more substantial correlation coefficients (sheep: 0.35 0.28;
guinea pigs: 0.55 0.32). Adding rabbits to an interspecies comparison of
low abrasive dental wear (pelleted lucerne diet), the softer enamel of the
hypselodont species showed a smaller data range for DMT parameters (guinea
pigs 0.49 0.32, rabbit 0.19 0.18, sheep 0.78 0.22) but again slightly
higher correlations coefficients compared to the hypsodont teeth (guinea pigs 0.55 0.31, rabbits 0.56 0.30, sheep 0.42 0.27). The findings suggest
that the softer enamel of fast-replaced ever-growing hypselodont cheek teeth
shows a greater inherent wear trace consistency, whereas the harder enamel
of permanent and non-replaced enamel of hypsodont ruminant teeth records
less coherent wear patterns. Because consistent diets were used across taxa,
this effect cannot be ascribed to the random overwriting of individual wear
traces on the more durable hypsodont teeth. This matches literature reports
on reduced DMT pattern consistency on harder materials; possibly, individual
wear events become more random in nature on harder material. Given the
species-specific differences in enamel characteristics, the findings suggest a
certain species-specificity of DMT patterns.
|
14 |
Análise da assembleia fitolítica do solo aplicada no holoceno médio: caso da Estação Ecológica da Mata Preta Abelardo Luz (SC) / Analysis of soil phytolith assemblage applied to the middle-holocene: case of the Mata Preta Ecological Station - Abelardo Luz (SC)Ewald, Paula Louíse de Lima Felipe 02 June 2015 (has links)
Made available in DSpace on 2017-05-12T14:42:14Z (GMT). No. of bitstreams: 1
Paula_Ewald.pdf: 4676802 bytes, checksum: c77cee71420720dcbe5dd9d247b3cb6a (MD5)
Previous issue date: 2015-06-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In the Quaternary period, the south of Brazil has suffered from paleoclimate instabilities which have generated changes in the landscape. Pedological, sedimentological and paleoenvironmental reconstructions studies have been developed by the group Gênese e Evolução de Superfícies Geomórficas e Formações Superficiais - UNIOESTE-FB to investigate the paleoclimate influence on the landscape setting of the Southwest region in Paraná and Northwest region in Santa Catarina States. Aiming to contribute with these studies, this research has sought to investigate the evolution of the vegetation at Ecological Station Mata Preta in Abelardo Luz (Santa Catarina State) and to verify the hypothesis of occurrence of vegetation changes over the Holocene in the studied area. Specifically, the goal was to determine the phytolith signature of the current vegetation and to assess its variability in the superficial soil horizons under the Mixed Ombrophylous Forest (FOM - Araucaria Forest) and to know the historical trajectory of the changes in the vegetation of the area of study during the Holocene Era. Routine physical and chemical analyses have been used to characterize a soil profile and phytolith and isotopic analyses (δ13C of the soil organic matter - SOM and datation14Cof humin fraction) in a soil profile (Profile 1) and more three Control Points (PC1, PC2 and PC3). The physical and chemical analyses of the soil allowed the classification of the studied soil as a Humic Dystrophic Inceptisol. The values of δ13C of the SOMpointed to a vegetation change between the Middle Holecene and the Late and the phytolith assembly of the soil allowed the refining of this interpretation. Thus, it is possible to infer that his soil registers a period during which the vegetation was formed by a prevailing community of C4plants (more open than the current one), in the Middle/Early Holocene (6.235-6.215 years Cal. AP), evolving to a mixed vegetation, more forested and similar to the current one, composed, predominantly, of C3plants, in the Late Holocene (from 840 to 835 years cal. A.P.) which evolved to the current FOM. Based on the litterphytolith assemblage and on the superficial layers of the Inceptisol and the PC´s, it has been defined the phytolith signature of the FOM, which is formed by 14 morphotypes of phytoliths which represent the families of Poaceae (subfamilies Panicoid; Pooid; Chloridoid and Bambusoid), Eudicotiledoneae, Arecaceae and Cyperaceae. / No período Quaternário, o Sul do Brasil passou por instabilidades paleoclimáticas que geraram mudanças nas paisagens. Estudos pedológicos, sedimentológicos e de reconstrução paleoambiental têm sido desenvolvidos pelo grupo Gênese e Evolução de Superfícies Geomórficas e Formações Superficiais (UNIOESTE-FB) para investigar a influência paleoclimática na configuração da paisagem do Sudoeste do Paraná e Noroeste de Santa Catarina. Visando contribuir com estes estudos, a presente pesquisa buscou investigar a evolução da vegetação na Estação Ecológica Mata Preta em Abelardo Luz (SC) e verificar a hipótese de ocorrência de trocas de vegetação ao longo do Holoceno na a área estudada. Especificamente, objetivou-se determinar a assinatura fitolítica da vegetação atual e avaliar a sua variabilidade nos horizontes superficiais do solo sob a Floresta Ombrófila Mista FOM (Mata de Araucária) e conhecer a trajetória histórica das mudanças da vegetação da área de estudo durante a Época Holocênica. Foram empregadas análises físicas e químicas de rotina para caracterização de um perfil de solo e análises fitolíticase isotópicas (δ13C da matéria orgânica do solo e datação 14C da fração humina) em um perfil de solo (Perfil 1) e em três Pontos de Controle (PC1, PC2 e PC3). As análises físicas e químicas do solo permitiram classificar o solo estudado como um CAMBISSOLO HÚMICO. Os valores de δ13C da matéria orgânica do solo (MOS) apontaram para uma troca de vegetação entre o Holoceno Médio e o Superior e a assembleia fitolítica do solo permitiu o refinamento dessa interpretação. Assim é possível inferir que este solo registra uma fase em que a vegetação era formada por uma comunidade predominantemente de plantas C4 (vegetação mais aberta que a atual), no Holoceno Médio/Inferior (6.235-6.215 anos Cal. AP), evoluindo para uma vegetação mista, mais florestada e semelhante à atual, composta predominantemente por plantas C3 no Holoceno Superior (de 840 e 835 anos cal. A.P) que evoluiu para a atual FOM. Com base na assembleia fitolítica da serrapilheira e das camadas superficiais do Perfil de CAMBISSOLO e dos PC, definiu-se a assinatura fitolítica da FOM, que é formada por 14 morfotipos de fitólitos representativos das famílias Poaceae (subfamílias Panicoid; Pooid; Chloridoid e Bambusoid), Eudicotiledoneae, Arecaceae e Cyperaceae.
|
15 |
Approche géomorphologique de la vallée de Deli et étude géoarchéologique du site historique de Kota Cina (Sumatra Nord, Indonésie) / Geomorphological approach of the Deli Valley and geoarchaeoligical study of the historic site of Kota Sina (Sumatra North, Indonesia)Chabot, Yohan 07 December 2017 (has links)
La reconstitution des paléoenvironnements et la compréhension des dynamiques géomorphologiques sont de plus en plus appréhendées au regard des recherches archéologiques. Toutefois, en Indonésie, cette approche est encore peu usitée. L’étude du site de Kota Cina (Sumatra Nord, Indonésie) entreprise dans le cadre de cette thèse, est un travail pionnier qui vise à comprendre les changements environnementaux à l’interface Homme/Nature, dans le but d’une reconstitution paléogéographique. Cet ancien comptoir commercial portuaire du Détroit de Malacca, actif entre les XIème et XIVème siècles AD, se trouve aujourd’hui à 7 km du rivage. Afin de s’interroger sur les variables de contrôle naturelles et anthropiques de l’évolution paysagère de la région, des investigations ont été menées à Kota Cina et dans la vallée de Deli. Deux approches ont été privilégiées : (1) une approche géomorphologique qui permet de reconstituer les dynamiques hydro-sédimentaires du site et de sa vallée ; (2) une approche biogéographique à travers une analyse du contenu phytolithiques des dépôts de Kota Cina, afin de renseigner l’évolution de la végétation du site. Cette étude met en exergue des évolutions paléoenvironnementales notables, en réponse à des forçages singuliers. Le volcanisme pré-holocène de la région a engendré par son détritisme un remplissage majeur de la vallée. La réponse hydro-sédimentaire holocène a modifié la géomorphologie de la région par une forte incision et un important transfert sédimentaire. Enfin, à l’époque historique, une nouvelle transformation paysagère a eu lieu avec l’anthropisation du milieu, notamment à partir du XIXème siècle avec l’essor des plantations coloniales. / Paleoenvironment reconstructions and geomorphological dynamics understanding are increasingly being considered with regards to archaeological research. However, in Indonesia, this approach remains unusual. The present study of Kota Cina site (North Sumatra, Indonesia) is a pioneering work that aims to understand environmental changes dynamics at the human/nature interface for the purpose of paleogeographic reconstruction. Kota Cina is an ancient trade harbour of the Strait of Malacca. It was active between the XIth and the XIVth centuries AD. Nowadays, the site is located at 7 km from the coast. In order to examine the implication of natural and anthropogenic factors in the landscape changes of the region, investigations were carried out at Kota Cina and the Deli Valley. Two approaches were developed: (1) a geomorphological approach to reconstitute the hydro-sedimentary dynamics of Kota Cina site and its valley; (2) a biogeographical approach to reconstruct the vegetation changes at Kota Cina from a phytolith analysis of the site deposits. This work highlights important paleoenvironment changes as response to unique forcings. The pre-Holocene volcanism of the region generated a major filling of the valley by its detritism. The Holocene hydro-sedimentary response has altered the geomorphology of the region through a strong incision and significant sediment transfer. Finally, during the historical period, new landscape changes took place with the environment anthropisation, especially from the XIXth century with the development of colonial plantations.
|
16 |
Casting no shadow : overlapping soilscapes of European-Indigenous interaction in northern SwedenGreen, Heather F. January 2012 (has links)
The Sámi’s past activities have been documented historically from a European perspective, and more recently from an anthropological viewpoint, giving a generalised observation of the Sámi, during the study period of AD200-AD1800, as semi-nomadic hunter gatherers, with several theories suggesting that interaction with Europeans, through trade, led to the adoption of European activities by certain groups of the Sámi (Eiermann, 1923; Paine, 1957; Manker and Vorren, 1962; Bratrein, 1981; Mathiesen et al, 1981; Meriot, 1984). However, there is almost no information on the impact the Sámi had on the landscape, either before or after any adoption of European activities, and none investigating what cultural footprint or indicators would remain from Sámi or European occupation and/or activity within the typically podzolic soils of Northern Sweden. Consequently the thesis aims to contribute to the gap in knowledge through the formation of a podzol model identifying the links between anthropogenic activity and the alteration of podzol soils, and through the creation of soils based models which identify the cultural indicators associated with both Sámi and European activity; formed from the identification of cultural indicators retained within known Sámi and European sites. The methods used to obtain the information needed to achieve this were the pH and magnetic susceptibility from bulk soil samples and micromorphological and chemical analysis of thin section slides through the use of standard microscopy and X-ray fluorescence from a scanning electron microscope. The analysis revealed that the Sámi had an extremely low impact on the landscape, leaving hard to detect cultural indicators related to reindeer herding in the form of reindeer faecal material with corresponding phosphorous peaks in the thin section slides. The European footprint however, was markedly different and very visible even within the acidic soil environment. The European indicators were cultivation based and included phosphorous and aluminium peaks as well as a deepened, highly homogenised plaggen style anthropogenic topsoil rich in ‘added’ materials. An abandoned European site which visibly and chemically shows the formation of a secondary albic horizon within the anthropogenic topsoil also provides an insight into the delicate balance of cultivated soil in northern Sweden, whilst reinforcing the outputs identified in the podzol model. Due to the almost invisible Sámi footprint on the landscape, areas of overlap were impossible to identify however, there was no evidence of the adoption of European cultivation activities at any of the Sámi sites investigated. The only known area of interaction between the two cultures was an official market place which had been a Sámi winter settlement prior to its use as a market site. This site showed none of the reindeer based Sámi indicators or the cultivation based European indicators, but did contain pottery fragments which could be linked to trade or occupation. Overall, the thesis reinforces the low impact expected of the semi-nomadic Sámi and sheds light on the underlying podzolic processes influencing the anthropogenically modified soils of Northern Sweden. The podzol model is reinforced by several findings throughout the thesis and the soils based cultural indicator models for both Sámi and European activity have been successfully tested against independent entomological and palynological data and therefore provide reliable reference material for future studies.
|
17 |
A History of Place: Using Phytolith Analysis to Discern Holocene Vegetation Change on Sanak Island, Western Gulf of AlaskaWilbur, Cricket C. January 2013 (has links)
No description available.
|
Page generated in 0.083 seconds