Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 21 for “"alpha and beta diversity"”.
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Soil Microbial Community Response to Human Decomposition in Michigan's Upper Peninsula
… facility characterized by cold temperatures, sandy soil, over 100 inches of snow annually, and close proximity to Lake Superior.</p> <p>Existing soil samples collected from four human donors at three sample sites (Head, Torso, Legs) are the subject of analysis for this project. One donor was …
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Diversity and species composition of two different moth families (Lepidoptera: Arctiidae vs. Geometridae) along a successional gradient in the Ecuadorian Andes
The diversity of two very species-rich families of arctiid and geometrid moths was investigated in a montane area in the Andes in southern Ecuador (Reserva Biológica San Francisco, 3°58´ S, 79°5´ W) along a succession gradient ranging from a barely vegetated landslide area to mature forest …
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From metacommunity dynamics to rapid biodiversity assessment: DNA-based approaches expand horizons in both fundamental and applied ecology
… recognised as having enormous potential to expand horizons in ecology, but the promise remains substantially unfulfilled. In this thesis, I apply genetic approaches to two ecological problems that have proved difficult to solve using traditional techniques. Chapters 1 and 2 apply molecular …
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How successful is grassland restoration after removal of pine plantations on the eastern shores of Lake St Lucia?
The coastal grasslands that occur along the Eastern Shores of Lake St. Lucia are rich in plant species, including endemics. These grasslands in North KwaZulu-Natal, South Africa, are remnants of a severely threatened vegetation type. Large portions of the Eastern Shores have been utilized for …
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Larval Fish Assemblages of Three Eastern South Dakota Rivers
Frequent disturbances and extreme environments make prairie streams, such as those in eastern South Dakota, highly unpredictable. Fishes in these streams have adopted reproductive strategies that allow for rapid recolonization after frequent and sometimes intense floods and droughts. New stresses, …
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High-throughput sequencing to understand pathogen carriage and transmission
… technology in the study of pathogen biology and pathogen transmission. In this thesis I have studied the human nasal carriage of *Staphylococcus aureus* and, in response to the SARS-CoV-2 pandemic, I examine the transmission of SARS-CoV-2, two critically important human pathogens. To address …
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Historical contingency and priority effects impact the decomposition of dead microbial biomass
… can significantly impact both the structure and functioning of ecological communities. These so-called ‘priority effects’ can occur when the early arriving species modify their environment to make it more or less suitable for subsequent colonizers (i.e., niche modification) or when the early …
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Bryophyte and macrolichen diversity of the Purdiaea nutans forest in southern Ecuador and its relationship to soil, climate and vegetation structure
… more likely triggered by historical fire events and a combination of site specific abiotic factors, related to topography, geology, pedology, and macroclimate. Neither the terrestrial nor the epiphytic bryophyte and macrolichen species richness or composition were affected by the unusual tree …
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Petroleum effects on soil microbial communities
… oil reservoirs at the Espirito Santo, Campos and Santos basins, can represent an excellent opportunity to meet the country‟s economic and energetic demands. However, offshore exploration offers risks to the microbiota and the whole sea life. Microbes are responsible for nutrient cycling can …
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Ground - dwelling arthropods in a biosphere reserve: patterns of diversity and conservation implications
Invertebrate diversity is often neglected in conservation planning initiatives. There are also very few large-scale diversity studies in Africa, with most studies being restricted to single properties and spatial extents that are on average not much larger than 30 km2. Here, we provide a …
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Analysis of Salivary Microbiota in Patients with Full-arch Implant Supported Fixed Prostheses
… either changes in local or systemic conditions and is associated with increased risk of caries, periodontal disease, oral cancer and systemic diseases such as diabetes, cardiovascular disease, etc. Use of dental implants for rehabilitation of fully edentulous patients or those with terminal …
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Altered Vulvar Microbiomes in Vulvar Lichen Sclerosus
… Vulvar lichen sclerosus (VLS) is a chronic and progressive dermatosis that most commonly affects the anogenital region of postmenopausal women. VLS etiology is incompletely understood, though a role for immune system dysregulation has been suggested given associations with autoimmune …
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The Impacts of Disruptive Environmental Change on Vital Microbial Ecosystems
<p>Microbes both affect the global nutrient and carbon cycles that influence climate change and our modern environment, and are in turn influenced by environmental change. Through resource acquisition, metabolism, symbiosis with plants and other organisms, and functional & taxonomic composition, …
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Phenotypic and microbial influences on dairy heifer fertility and calf gut microbial development
Pregnancy loss and calf death can cost dairy producers more than $230 million annually. While methods involving nutrition, climate, and health management to mitigate pregnancy loss and calf death have been developed, one potential influence that has not been well examined is the reproductive …
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The effects of prebiotics on the growth performance and gastrointestinal microflora modulation in oreochromis mossambicus in Hardap region, Namibia
… across the world is growing exponentially, and has certainly gained popularity among small scale farmers in Namibia. Aquaculture aims to take on the increasing demand of fish as a food source in light of depleting fish stocks in natural water systems. Therefore, studies aiming to improve …
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REDUCING ANTIMICROBIAL RESISTANCE RISKS AND ANTIBIOTIC USAGE IN DAIRY FARMING: MICROBIOLOGICAL INSIGHTS AND ALTERNATIVE STRATEGIES
… a need for comprehensive research to address AMR and reduce antibiotic use in food animals, especially in dairy livestock systems. This thesis summarizes four research projects that investigate the impact of AMR in both animals and humans and explore the reduction of antibiotic use in intramammary …
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Microbiology of marine sponges: from community structure to symbiont function
… marine sponge microbiota poses unique conceptual and analytical challenges, as microbial species may number in the thousands. One way to overcome this issue is to consider only the persistent and/or abundant species, i.e. the „core‟ community. While this approach has been widely used to analyse …
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Encapsulated butyric acid as a functional ingredient in canine health
… effects in the intestinal tract of humans and animals (Guilloteau et al., 2010; Bedford and Gong, 2017; Kim et al., 2025). Butyric acid is recognized to play a large role in maintaining gut immunity and gut barrier function, and it also contributes to broader systemic effects including …
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Effects of yeast products on immune response and intestinal health of dogs and mice
With growing pet populations and the trend of pet humanization, the demand for functional ingredients that provide health benefits beyond basic nutrition has continued to increase in the pet food industry. Yeast products may serve as functional ingredients due to their potential health benefits as …
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Change in the Structure of Soil Microbial Communities in Response to Waste Amendments
… litter, which contains a substantial C, energy, and nutrient supply, but also antibiotic resistance genes (ARG), antimicrobials, and a multitude of microbial species. This project seeks to primarily assess if there is a change in bacterial community structure in response to poultry litter …
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