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 10 of 10 for “"polar desert"”.
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Isolation of psychrophilic halophiles from the Antarctic polar desert
Saline soils in the Dry Valley region of McMurdo Sound, Antarctica, contained bacteria showing salt tolerance or requirement. Soils were plated by the spread plate method on soil extract-peptone-yeast extract media to which sodium chloride had been added in concentrations from 0 to15 per cent …
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Hydrology and Hydrogeochemistry of the South Fork, Wright Valley, Southern Victoria Land, Antarctica
… systems have features reflective of the regional polar desert environment, and particularly of the extreme cold and aridity.
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Investigating dissolved organic matter cycling in High Arctic ponds and soils
… layer detachment scar, mesic tundra, unvegetated polar desert, vegetated polar desert, and wet sedge. Soil CO2 emissions were measured over short-term soil incubation experiments and compared with the optical and chemical characteristics of soil water-extractable organic matter (WEOM) before and …
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Heterotrophic Microbial Colonization of the Interior of Shocked Rocks from the Haughton Impact Structure, Devon Island, Nunavut, Canadian High Arctic
The polar desert is one of the most extreme environments on Earth. In these regions, microorganisms have had to develop novel strategies and adaptations in order to survive. One of the most effective such strategies has been developed by mkroorganisms, known as endoliths, which live in the interior …
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Landscape and environmental controls on soil organic matter decomposability in the High Arctic
… SOC decomposability than mesic tundra (MT) and polar desert (PD) soils. Further evaluation of soils under dominant High Arctic plant types: Salix arctica Pall (SA), bare ground mats (BGM) and moss identified as Grimmia torquata Drumm. (GT) reveal that plant type significantly influences more …
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Limnological and paleolimnological investigations of environmental change in three distinct ecosystem types, Canadian High Arctic
… than freshwater bodies from the surrounding polar desert. In Chapter 5, I provide an examination of long-term environmental change from Melville Island, a region of the High Arctic for which no paleolimnological data exist. The timing of diatom shifts in a dated sediment core from a small …
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Biogeochemical and ecological responses to warming climate in High Arctic polar deserts
High Arctic polar deserts cover 26% of the Arctic and are found to store a larger amount of soil organic carbon (SOC) in the permafrost and to emit higher amounts of the main greenhouse gases (GHGs) than previously expected. However, the mechanisms of the main GHG production are not clear. …
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Environmental Controls Over the Distribution and Function of Antarctic Soil Microbial Communities
… limitations. Sampling was performed in the polar desert of Antarctica's McMurdo Dry Valleys, a model ecosystem which hosts microbially-dominated soil foodwebs and displays heterogeneously distributed soil properties across the landscape. Results for Chapter 2 indicate differential effects of …
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Resolving functional resilience of microbial communities to climate-induced change in the McMurdo Dry Valleys of Antarctica
… for carbon acquisition under extreme aridity in polar deserts, being replaced by photosynthetic carbon fixation with prolonged exposure to wetness. To complement predictions made in situ using a space-for-time approach, this research incorporated temporal observations using manipulative …
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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 …