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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.
71

An Analysis of Faunal and Human Osteological Remains from the Eiden Site (33 Ln 14) of Sheffield, Ohio

Dennis, Karen Elizabeth January 1978 (has links)
No description available.
72

Taken to the grave. An archaeozoological approach assessing the role of animals as crematory offerings in first millennium AD Britain.

Worley, Fay L. January 2008 (has links)
The crematory funerary rites practiced by those living in parts of mainland Britain during the first millennium AD included burning complete or parts of animals on the pyre. This thesis highlights the potential for archaeozoological analysis of faunal pyre goods using assemblages from the first millennium AD as a dataset. Experimental study and the integration of current research from a number of disciplines is used to suggest that although pyrolysis and cremation practices fragment and distort burnt bone assemblages, careful analysis can reveal a wealth of data leading to the interpretation of various forms of pyre good. The results of the author¿s analysis of material from the sites of Brougham, Cumbria, St. Stephen¿s, Hertfordshire, Castleford, West Yorkshire and Heath Wood, Derbyshire are combined with data from other published cemeteries to suggest a series of chronological and regional continuities in the use of animals but with a distinct change at the start of the Early Medieval period. The results from Brougham are particularly significant as they alter preconceived views on the utilisation of animals in Romano-British funerary practice. Cremation burials in first millennium AD Britain are shown to include the burnt remains of predominantly domestic taxa with occasional wild species. The pyre goods are interpreted as representing food offerings, companions, amulets, gaming items and sacrifices. This thesis demonstrates that cremated animal bone should not be disregarded but rather valued as source of archaeozoological data, and a significant functional tool for interpreting past funerary behaviour and animal utilisation.
73

Microbial community structure and nematode diversity in soybean-based cropping systems / Chantelle Jansen

Jansen, Chantelle January 2014 (has links)
Soil is an important ecosystem that supports a wide variety of organisms such as bacteria, fungi, arthropods and nematodes. This sensitive ecosystem may be influenced by various factors, including agricultural management practices. With the introduction of genetically modified (GM) glyphosate-tolerant (RoundUp ® Ready: RR) crops, herbicides such as glyphosate have been increasingly used. However, little is known about the effect of glyphosate on the biological communities in these herbicide-sprayed soils. With the intimate proximity that microorganisms and nematodes have with the roots of plants, these organisms can be used to assess changes that may occur in the soil surrounding roots of RR crops. The aim of this study was to determine microbial community structure and nematode diversity, with emphasis on that of non-parasitic nematodes, in soil samples from conventional soybean (CS) - and RR- soybean fields compared to that in adjacent natural veld (NV) areas. Samples were collected from twenty three sites at six localities that are situated within the soybean-production areas of South Africa. These sites represented fields where RR and CS soybean grew, as well as surrounding NV. All RR fields have been treated with glyphosate for no less than five years. Microbial community structures of the twenty three sites in the RR, CS and NV ecosystems were determined by phospholipid fatty acid (PLFA) analyses. Nematode diversity was determined by extracting the nematodes from soil samples and conducting a faunal analysis. Soil physical and chemical properties were determined by an independent laboratory, Eco-Analytica (North West University, Potchefstroom) according to standard procedures. Results from this study indicated differences in microbial community structure between the various localities. However, there were no significant (p ≤ 0.05) differences in microbial community structures between RR- and CS ecosystems. Soils of both RR- and CS crops were primarily dominated by bacteria. Nematode identification and faunal analysis also indicated no significant (p ≤ 0.05) differences between the different non-parasitic/beneficial nematodes that were present in soils of these two ecosystems during the time of sampling. Non-parasitic nematode communities were primarily dominated by bacterivores. A faunal analysis indicated that most of the sites contained enriched, but unstructured soil food-webs. However, four of the sites showed enriched and structured food webs due to the presence of non-parasitic nematodes with high coloniser-persister (cp) values. Relationships between non-parasitic nematode – and microbial communities showed that there was a positive relationship between nematode functional groups and their corresponding microbial prey. From the results obtained in this study, it can be concluded that the community structures of both non-parasitic nematodes and microorganisms shared similarities. These community structures showed no long-term detrimental effects of glyphosate application in the soils surrounding roots of RR soybean crops. Relationships existed between non-parasitic nematode and microbial communities in the rhizosphere of soybean crops and natural veld. For example, bacterivore nematodes had a strong positive relationship with gram-negative bacteria. Similar but weaker relationships also existed between carnivores, omnivores, plantparasitic nematodes and gram-negative bacteria. A positive relationship also existed between fungivores and fungal fatty acids. This emphasises the value of these organisms as indicators of soil health and also the impact that agricultural practices can have on soils. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014
74

Microbial community structure and nematode diversity in soybean-based cropping systems / Chantelle Jansen

Jansen, Chantelle January 2014 (has links)
Soil is an important ecosystem that supports a wide variety of organisms such as bacteria, fungi, arthropods and nematodes. This sensitive ecosystem may be influenced by various factors, including agricultural management practices. With the introduction of genetically modified (GM) glyphosate-tolerant (RoundUp ® Ready: RR) crops, herbicides such as glyphosate have been increasingly used. However, little is known about the effect of glyphosate on the biological communities in these herbicide-sprayed soils. With the intimate proximity that microorganisms and nematodes have with the roots of plants, these organisms can be used to assess changes that may occur in the soil surrounding roots of RR crops. The aim of this study was to determine microbial community structure and nematode diversity, with emphasis on that of non-parasitic nematodes, in soil samples from conventional soybean (CS) - and RR- soybean fields compared to that in adjacent natural veld (NV) areas. Samples were collected from twenty three sites at six localities that are situated within the soybean-production areas of South Africa. These sites represented fields where RR and CS soybean grew, as well as surrounding NV. All RR fields have been treated with glyphosate for no less than five years. Microbial community structures of the twenty three sites in the RR, CS and NV ecosystems were determined by phospholipid fatty acid (PLFA) analyses. Nematode diversity was determined by extracting the nematodes from soil samples and conducting a faunal analysis. Soil physical and chemical properties were determined by an independent laboratory, Eco-Analytica (North West University, Potchefstroom) according to standard procedures. Results from this study indicated differences in microbial community structure between the various localities. However, there were no significant (p ≤ 0.05) differences in microbial community structures between RR- and CS ecosystems. Soils of both RR- and CS crops were primarily dominated by bacteria. Nematode identification and faunal analysis also indicated no significant (p ≤ 0.05) differences between the different non-parasitic/beneficial nematodes that were present in soils of these two ecosystems during the time of sampling. Non-parasitic nematode communities were primarily dominated by bacterivores. A faunal analysis indicated that most of the sites contained enriched, but unstructured soil food-webs. However, four of the sites showed enriched and structured food webs due to the presence of non-parasitic nematodes with high coloniser-persister (cp) values. Relationships between non-parasitic nematode – and microbial communities showed that there was a positive relationship between nematode functional groups and their corresponding microbial prey. From the results obtained in this study, it can be concluded that the community structures of both non-parasitic nematodes and microorganisms shared similarities. These community structures showed no long-term detrimental effects of glyphosate application in the soils surrounding roots of RR soybean crops. Relationships existed between non-parasitic nematode and microbial communities in the rhizosphere of soybean crops and natural veld. For example, bacterivore nematodes had a strong positive relationship with gram-negative bacteria. Similar but weaker relationships also existed between carnivores, omnivores, plantparasitic nematodes and gram-negative bacteria. A positive relationship also existed between fungivores and fungal fatty acids. This emphasises the value of these organisms as indicators of soil health and also the impact that agricultural practices can have on soils. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2014
75

KwaGandaganda : an archaeozoological case study of the exploitation of animal resources during the early Iron Age in KwaZulu-Natal

Beukes, Catharina F. 11 1900 (has links)
KwaGandaganda is an Early Iron Age (EIA) site in the .Mngeni valley (KwaZulu-Nata~ South Africa). Three cultural phases, Msuluzi, Ndondondwane and Ntshekane, dating between AD 620- AD 1030 were identified. The objective was to establish the extent of animal exploitation during the EIA in KwaZulu-Natal by means of faunal analysis, using internationally accepted methods. The collection included 41 006 fragments of which 22.9% were identifiable. A large number of species (68) were identified, including Rattus rattus. The collection yielded the largest quantity of ivory chips ever found on an EIA site in southern Africa, as well as an extensive variety of pathological specimens, mostly from Bos taurus. Several possible divining bones were present in the sample. Herd management, hunting strategies, gathering activities, fishing and trading of animal goods during the EIA were discussed, while the consequences of the unique excavation methods (i.e. the use of bulldozers) were also commented upon. / Anthropology and Archaeology / M.A. (Anthropology)
76

Influence des communautés microbiennes sédimentaires sur la répartition faunistique dans les sites hydrothermaux et les zones d'émissions de fluides froids du bassin de Guaymas / Influence of sedimentary microbial communities on the faunistic distribution in hydrothermal sites and the cold seeps emission zones of the Guaymas Basin

Cruaud, Perrine 01 April 2014 (has links)
Au niveau des fonds océaniques, souvent considérés comme des déserts aux conditions de vie extrêmes, des oasis luxuriants de vie existent pourtant. Les sources hydrothermales et les suintements froids, principalement localisés au niveau des dorsales océaniques et des marges continentales, vont permettre le développement de communautés microbiennes et animales très particulières. Le Bassin de Guaymas, situé dans le Golfe de Californie (Mexique) présente la particularité de regrouper à la fois une zone de sources hydrothermales et une zone de suintements froids, situées à une soixantaine de kilomètres l’une de l’autre, et toutes deux recouvertes par une épaisse couche sédimentaire. Ces deux zones sont également colonisées par des étendues de bivalves, des buissons de vers tubicoles ainsi que de tapis microbiens blancs ou colorés comparables. Afin de mieux comprendre le fonctionnement global de ces deux types d’écosystèmes et notamment le rôle structurant des communautés microbiennes sédimentaires sur la répartition des différents assemblages de surface, les travaux entrepris dans cette thèse se proposaient d’étudier les communautés microbiennes sédimentaires associés à la zone de suintements froids (Marge de Sonora) et la zone de sources hydrothermales (Southern Trough) du Bassin de Guaymas. Pour cela, la diversité des communautés microbiennes (Bacteria et Archaea) de différents habitats caractérisés par une faune et des profils géochimiques particuliers, a été étudiée grâce à l’utilisation d’une technique de séquençage haut-débit, le pyroséquençage par la technique du 454, combinée à d’autres techniques comme le FISH ou la PCR quantitative. Cette étude a permis de déterminer que la structure et la diversité des communautés microbiennes dans ces sédiments étaient très spécifiques de ces environnements. Par ailleurs, les colonisateurs présents en surface des sédiments reflétaient des profils géochimiques et des communautés microbiennes très différentes au sein des sédiments. Dans les sédiments colonisés par les tapis microbiens, riches en méthane, les communautés microbiennes dominantes (ANME, Deltaproteobacteria…) utiliseraient notamment les émissions de méthane des couches sédimentaires profondes et produiraient d'importantes concentrations de sulfures, nécessaires à l’installation des communautés microbiennes thiotrophes de surface formant les tapis. Ces fortes concentrations en sulfure excluraient en revanche les communautés animales de ce périmètre. A contrario, dans les sédiments présentant de faibles concentrations en méthane et en sulfure, permettant l'installation d’assemblages faunistiques variés, les communautés microbiennes méthanotrophes anaérobies et productrices de sulfure étaient minoritaires. L'activité et le métabolisme de ces colonisateurs de surface pourraient par ailleurs permettre le développement des lignées microbiennes détectées dans ces habitats (MBG-D, Chloroflexi…). L'analyse des larges jeux de données obtenus au cours de cette étude nous a donc permis de mettre en évidence un système dynamique complexe fonctionnant en équilibre entre les communautés microbiennes sédimentaires, les organismes colonisant la surface du sédiment et la composition géochimique des eaux interstitielles. / Whereas the deep-sea environment is often considered to be a desert, hydrothermal vents andcold seeps provide “oases” of biological activity on the ocean floor. Vent and seep ecosystems support complex food webs based on microbial chemoautotrophic primary production. These hydrothermal vent and cold seeps ecosystems both release hydrocarbon- and sulfide-rich fluids,fueling various surface assemblages such as mat-forming giant bacteria or symbiont-bearinginvertebrates (e.g. bivalves, tubeworms). In the Guaymas Basin, the nearby presence at a few tens of kilometers of cold seeps and hydrothermal vents coupled with comparable sedimentary settings and depths offer a unique opportunity to assess and compare the microbial community composition of these ecosystems. Tobetter understand their overall functioning, we studied sedimentary microbial communities associated with cold seep and hydrothermal vent areas in the Guaymas Basin. The diversity of microbial communities inhabiting sediments was studied using high throughput sequencing (454pyrosequencing), combined with complementary approaches, such as FISH and quantitative PCR. This study reveals that sediments found in the Guaymas Basin were colonized by microbial communities typically found in these types of ecosystems. Our results revealed a high similarity between microbial communities composition associated with the cold seep and hydrothermal vent areas as a probable consequence of the sedimentary context. Nonetheless, thermophilic and hyperthermophilic lineages (e.g.: Thermodesulfobacteria, Desulfurococcales, etc) were exclusively identified in hydrothermally influenced sediments highlighting the strong influence of temperature gradients and other hydrothermally-related factors on microbial community composition. Furthermore, sediments populated by different surface assemblages show distinct porewater geochemistry features and are associated with distinct microbial communities. Indeed, in the sediments underlying microbial mats characterized by high methane porewater concentrations,microbial communities were dominated by anaerobic methane oxidizers (ANME), known to produce sulfide which provides high fluxes of sulfide to the seafloor. In contrast, sediment associated microbial communities underlying faunal assemblages were characterized by a lower biomass and lower methane porewater concentrations in sediments, limiting porewater sulfide concentrations. Without elevated and toxic sulfide concentrations, faunal assemblages can colonize the surface. Together, geochemical and microbial surveys indicate that porewater methane concentrations play an important role in the microbial community structure and subsequently in the establishment of the surface colonizers. Furthermore, presence and activity of the surface colonizers influence the underlying microbial communities probably because of modification of energy source availabilities. Finally, the existence of similar microbial populations between the two ecosystems also raises the question of their dispersal mechanisms. Our results support the hypothesis of a potential continuity among deep-sea ecosystems. In absence of physical borders, environmental conditions (temperature, specific compounds associated withhydrothermal fluids) might select specific and highly adapted microorganisms from the pool of microorganisms dispersed globally across the seafloor.
77

Butterfly communities in the natural landscape of West Khentej, northern Mongolia: diversity and conservation value / Schmetterlingsgemeinschaften in der Naturlandschaft der Westkhentie, Nordmongolei: Biodiversität und Naturschutzwert

Gantigmaa, Chuluunbaatar 27 January 2005 (has links)
No description available.
78

KwaGandaganda : an archaeozoological case study of the exploitation of animal resources during the early Iron Age in KwaZulu-Natal

Beukes, Catharina F. 11 1900 (has links)
KwaGandaganda is an Early Iron Age (EIA) site in the .Mngeni valley (KwaZulu-Nata~ South Africa). Three cultural phases, Msuluzi, Ndondondwane and Ntshekane, dating between AD 620- AD 1030 were identified. The objective was to establish the extent of animal exploitation during the EIA in KwaZulu-Natal by means of faunal analysis, using internationally accepted methods. The collection included 41 006 fragments of which 22.9% were identifiable. A large number of species (68) were identified, including Rattus rattus. The collection yielded the largest quantity of ivory chips ever found on an EIA site in southern Africa, as well as an extensive variety of pathological specimens, mostly from Bos taurus. Several possible divining bones were present in the sample. Herd management, hunting strategies, gathering activities, fishing and trading of animal goods during the EIA were discussed, while the consequences of the unique excavation methods (i.e. the use of bulldozers) were also commented upon. / Anthropology and Archaeology / M.A. (Anthropology)
79

An archaeozoological and ethnographic investigation into animal utilisation practices of the Ndzundza Ndebele of the Steelpoort River Valley, South Africa, 1700 AD – 1900 AD

Nelson, Cindy 01 October 2009 (has links)
Focussing on Archaeozoological faunal analysis, this dissertation aims to investigate the animal food utilization practices of the Ndzundza Ndebele by combining archaeozoologcial methods, archaeological data, ethnographic and historic information. The Ndzundza Ndebele inhabited three different sites in the Steelpoort River Valley during c. 1700 AD – 1900 AD. They were forced to relocate from KwaMaza and Esikhunjini to KoNomtjarhelo as a result of continual fighting between themselves and contemporary Iron Age/Historic communities, the British and the Boers during this period. I aim to identify the animal species utilized by the Ndzundza Ndebele in addition to whether or not the hostile and politically unstable period had any effect on Ndzundza animal food procurement, use and discard. Additionally I investigate whether the faunal remains recovered from the three sites can be used to identify ethnic affiliations, gender roles and ritual use with regards to animals and/or animal parts. Ultimately, I aim to demonstrate that faunal remains cannot be fully understood and interpreted without incorporating relevant ethnographic and/or historic information and as comprehensive an archaeological context as possible. Copyright / Dissertation (MA)--University of Pretoria, 2009. / Anthropology and Archaeology / unrestricted
80

The Ohio Pleistocene Mammal Database (OPMDB): Creation and Preliminary Taphonomic and Spatial Analyses

Terry, Ina M. 20 December 2013 (has links)
No description available.

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