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 17 of 17 for “"Microbial Mat"”.
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Microbial Mat Abundance and Activity in the McMurdo Dry Valleys, Antarctica
… can provide long-term, spatially-extensive estimates of primary production and are particularly well suited to remote environments, such as in the McMurdo Dry Valleys (MDV) of Antarctica, where cyanobacterial communities are the main drivers of primary production. These microbial communities …
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Characterisation of microbial Mat communities in meltwater ponds of the McMurdo ice shelf, Antarctica
… presented in this thesis examined the microbial and functional diversity of the meltwater ponds Fresh, Orange and Salt Ponds on the McMurdo Ice Shelf, near Bratina Island, Antarctica. These sites were chosen because of the ecological importance and absence of detailed characterisations …
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Influence of landscape-variation in geochemistry on taxonomic and functional composition of microbial mat communities in the McMurdo Dry Valleys, Antarctica
Microbial communities play critical roles in biogeochemical cycles of aquatic and terrestrial ecosystems, but studies of soil microbial communities have been limited by the diversity and complexity found in most ecosystems. Here we report on work investigating the functional diversity of microbial …
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Streams, stromatolites and the geometry of growth
… to a diffusive flux. The first system is a microbial mat which overlays a layer of precipitated mineral. The microbial mat grows in response to the diffusion of nutrients while the mineral layer grows in response to the precipitation of dissolved ions which diffuse through the microbial mat. …
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Cyanobacterial evolution and interactions with the Proterozoic world
… the rise of complex life is built largely upon microbial mat structures and some exceptionally well-preserved microbial fossils from the Proterozoic (2500 to 540 million years ago). Some of these exceptional fossils are identifiable as cyanobacteria that were preserved by pyrite, amorphous …
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Unique Preservation of Fossil Ghost Fish in the Green River Formation
… fossil poor Angelo Member in the Green River Formation in Fossil Basin, Wyoming. These two beds, termed “Ghost Fish” beds, contain fossil fish that are two-dimensional carbonaceous compressions with no bone and detailed soft part preservation. These beds were measured and samples were collected …
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Testing the ancient marine redox record from oxygenic photosynthesis to photic zone euxina
… the need to consider allochthonous and microbial mat sources and the role of basin restriction as alternative explanations for these biomarkers in the geologic record, in addition to an autochthonous planktonic source.
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Testing the ancient marine redox record from oxygenic photosynthesis to photic zone euxina
… the need to consider allochthonous and microbial mat sources and the role of basin restriction as alternative explanations for these biomarkers in the geologic record, in addition to an autochthonous planktonic source.
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Environmental controls on the distribution of bacterial membrane lipids
… characterization of water column and benthic microbial mat samples collected across geochemical and physiochemical gradients in the Eastern Tropical South Pacific oxygen minimum zone off the coast of northern Chile and in two ice-covered lakes of the McMurdo Dry Valleys, Antarctica. The …
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Dominant substrates used by methanogens in hypersaline environments
… and the and the Exportadora de Sal saltern. Microbial mat and/or sediments were amended with site water only or with site water and various substrates and incubated in N2(g) flushed serum vials. It was hypothesized that trimethylamine (TMA) would be a dominant substrate in all ponds. …
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An Integrated Approach to Improving Efficiency in Photosynthetic Microbial Systems
… cyanobacteria in biotechnology. A photosynthetic microbial mat, sourced from highly productive haloalkaline soda lakes, was previously used as inoculum for enrichment of a mono-cyanobacterial microbial consortium. In this thesis, the microbial composition and function of the productive …
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Evolutionary Ecology of the First Animal Ecosystems
… between newly settled juvenile organisms and microbial mat characteristics, supporting the claimed ecological importance of matgrounds in the Ediacaran and the ‘savannah’ hypothesis for the evolution of movement. In Chapter 3, I also find evidence for negative density-dependent mortality …
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Multi-scale Studies of Microbial Mats and Biocrusts: Integrating Remote Sensing with Field Investigations in Antarctica's McMurdo Dry Valleys
… more extreme ecosystems. In dense associations, microbial organisms can form visually conspicuous layers on sediment, soil, and rock surfaces, called microbial mats and biological soil crusts (i.e., biocrusts). Both microbial mats and biocrusts consist of cyanobacteria, moss, diatoms, and green …
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Identification of Quorum Sensing Genes in Hypersaline Microbial Mats
… unexplored biological reservoirs on earth. Microbial communities carry out biochemical processes, interactively, by functioning as social units and ultimately define the overall functionality of ecosystems. Bacterial communities in all ecosystems likely utilize signaling pathways to adapt to …
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Microtextures of Cyanobacterial Mats in Siliciclastic Sedimentary Environments (Modern & Ancient): Applications to the Search for Life on Mars
… new methods of how to detect and to identify microbial mats in siliciclastic sediments (modern and ancient), and to make recommendations on the applicability of MISS as biosignatures. Predominantly, I employed instrumentation portable by future rovers. To search for life on other planets, we …
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Stromatolitic Knobs in Storrs Lake, San Salvador, Bahamas: Insights into Organomineralization
… Island, Bahamas, contains well-developed microbial mats, some of which have developed calcified structures called microbialites. Many of these microbialites are laminated, and therefore classified as stromatolites. This study focuses on small stromatolitic knobs located in the southern …
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Bacterial and archaeal community structure across a gradient of saline lakes in Kiritimati, Republic of Kiribati
Microbial mats, multilayered sheets of microorganisms often found in extreme environments, are increasingly gaining attention for their utility and influence on the global carbon cycle. However, our understanding of the organisms that define microbial mats and how they vary across environmental …