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 14 of 14 for “"thermokarst"”.
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Thermokarst dynamics in central-eastern Beringia
… at reconstructing Late Quaternary permafrost and thermokarst dynamics in central-eastern Beringia, the terrestrial land mass connecting Eurasia and North America during glacial sea-level low stands. In order to investigate development, processes and influence of thermokarst dynamics, several …
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Thermokarst and thermal erosion : degradation of Siberian ice-rich permafrost
… high ice content of these permafrost deposits. Thermokarst and thermal erosion are two major types of permafrost degradation in periglacial landscapes. The associated landforms are prominent indicators of climate-induced environmental variations on the regional scale. Thermokarst lakes and …
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The impacts of thermokarst activity on a stream in the McMurdo Dry Valleys
… supports this idea is the discovery of extensive thermokarst degradation (permafrost thaw features) along the banks of Crescent Stream in Taylor Valley. In 2012, a large stretch of the West Branch of Crescent Stream was found to have significant thermokarst bank failures, while the adjacent East …
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Morphological evidence of past thermokarst in selected parts of the present temperate zone and its paleoenvironmental significance
Tato práce si klade za cíl charakterizovat reliktní termokrasové útvary, porovnat je s recentními formami, vymezit jejich lokalizaci a určit paleoenvironmentální podmínky na základě jejich morfologie a rozšíření. Přibližně půl milionu kmš evropského území bylo prozkoumáno za účelem nalezení znaků …
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Spatiotemporal dynamics of carbon cycling and thermokarst in response to climate and fire-regime changes in the Arctic tundra biome
… of climate change and fire disturbance on thermokarst disturbance (e.g. collapse of ground surface after permafrost thaw), and (3) the patterns of shrub expansion in heterogenous tundra landscape in response to accelerated warming and fire disturbance. My results indicate that fire …
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Remote sensing of recent changes in permafrost-influenced wetlands
Changes in thermokarst lakes have been identified across many high-latitude ecosystems at different spatial and temporal scales. With the declassification of the Landsat archive in 2008, it is now possible to conduct a near-complete yearly time series of homogenous geospatial imagery to assess the …
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Characterisation and evolution of periglacial landscapes in Northern Siberia during the Late Quaternary : remote sensing and GIS studies
… the Ice Complex was subject to extensive thermokarst processes since the Early Holocene. Permafrost deposits are not only an environmental indicator, but also an important climate factor. Tundra wetlands, which have developed in environments with aggrading permafrost, are considered a net …
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The hydrological and limnological characterization of two Canadian water catchments sensitive to anthropogenic influences: Crawford Lake, Ontario and Old Crow Flats, Yukon
… Arctic wetland that holds over 8700 shallow thermokarst lakes and drain a 14,000 km2 headwater basin via the Old Crow– Porcupine – Yukon River system. OCF is the traditional territory of the Vuntut Gwitchin First Nations who have observed widespread climate-induced landscape changes, …
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A Transfer Learning Approach for Automatic Mapping of Retrogressive Thaw Slumps (RTSs) in the Western Canadian Arctic
Retrogressive thaw slumps (RTSs) are thermokarst landforms that develop on slopes in permafrost regions when thawing permafrost causes the land surface to collapse. RTSs are an indicator of climate change and pose a threat to human infrastructure and ecosystems in the affected areas. As the …
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Relative influence of temperature and disturbance on vegetation dynamics in the Low Arctic : an investigation at multiple scales.
… warming will change the area affected by thermokarst disturbances like slumps. Taken together, my research indicates that the effects climate change will be magnified by shifts in the frequency of disturbance, initiating changes to Arctic vegetation with significant implications for global …
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Drivers of landscape evolution in northern ecosystems: Shrub expansion, vegetation-fire interaction, and permafrost degradation
… These changed wildfire frequencies along with thermokarst can free space and nutrients by removing and breaking down existing vegetation and organic matter, letting tall shrubs expand their range. Patterns tundra landscape evolution are complex, as the tundra of Alaska is far from a monolith, …
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The modification of arctic permafrost coastlines
The arctic region is undergoing the most rapid environmental change experienced on Earth, and the rate of change is expected to increase over the coming decades. Arctic coasts are particularly vulnerable because they lie at the interface between terrestrial systems dominated by permafrost and …