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Distribution and pattern morphology of pseudomorphs of thermal-conctraction-cracks features in Austria
Dufek, Jaroslav ; Křížek, Marek (advisor) ; Margold, Martin (referee)
During the cold Pleistocene episodes, the territory of Austria was at the forefront of nearby Alpine glaciation. The unglaciated area of Austria was part of the Central European periglacial zone, in which permafrost developed. The distribution of Upper Pleistocene permafrost, its character, but also its time classification in the western part of the Pannonian Basin is still unclear. It is also because ideas about the characteristics of Upper Pleistocene permafrost in this area have so far been based mainly on indirect biological or lithological records such as pollen grains, malacofauna snails, or loess-paleosol sequences. Until now, the evidence of direct geo-indicators of paleo-permafrost has been relatively limited, with unique relict frost-wedges, cryoturbations, or sporadic remains of thermokarst lakes depressions and pingos. The results present a new database of relict frost-wedges in Austria, which was created based on published literary sources, but mainly based on aerial imaginary available on Google Earth Pro. The results significantly expand (by hundreds of localities) the existing knowledge about the occurrence of relict frost-wedges, which have so far been located in Austria purely on the basis of excavated profiles and soil probes. The found polygons of frost-wedge pseudomorphs are an...
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Morphological feattures of ice wedge polygons in arctic zone.
Kysilka, Tomáš ; Křížek, Marek (advisor) ; Treml, Václav (referee)
Morphological features of ice wedge polygons in arctic zone Abstract This bachelor thesis deals with the subject of ice-wedge polygons including theirs morphological characteristics and conditions prerequisite for their creation. The paper states the conditions which allow and inhibit frost cracking of the ground. First part presents the conclusions of scientific literature published on the topic of permafrost, frost cracking, ice- wedges and ice-wedge polygons. Consequently the paper discusses the relation of ice-wedge polygons morphology to climate and lithology. Further the thesis analyzes morphological characteristics of ice-wedge polygonal net localized at southwest part of Banks Island, Canadian Arctic Archipelago. Acquired data and conclusions are confronted with published periglacial literature. Keywords: ice-wedge, ice-wedge polygons, frost cracking, permafrost, Banks Island, arctic zone
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Pingo morphology as a result of site and environmental characteristics
Kuznetsova, Evgeniia ; Křížek, Marek (advisor) ; Margold, Martin (referee)
This bachelor thesis deals with the study of pingos. The research part summarizes the morphological features of these landforms, the mechanisms of their origin and their developmental stages. The aim of this work is to describe the distribution of recent pingos on the Earth's surface, to characterize the limit natural conditions of pinog occurrence and to determine whether they are related to their morphology, prospectively to what extent. The results are based on a table containing individual environmental characteristics, which was created on the basis of a literature search. The results were further compared with the conclusions of previous studies. Pingos are of interest because they are indicators of the presence of permafrost and specific hydrological processes, and thus allow conclusions to be drawn about environmental conditions in the past and present.
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Past and Present Permafrost and Active-Layer Phenomena as Indicators of Late Quaternary Environmental Changes
Uxa, Tomáš ; Křížek, Marek (advisor) ; Dobiński, Wojciech (referee) ; Winkler, Stefan (referee)
Late Quaternary has seen numerous major permafrost expansions and retreats associated with alternating glacial and interglacial periods as well as stadials and interstadials, the research of which is necessary to understand the past environmental evolution, but also provides useful analogues for its present-day and future behaviour. How- ever, observations of permafrost and active-layer phenomena are still limited, and sometimes misleading, even in many present-day permafrost regions, and naturally less comprehensive evidence is available from areas where permafrost existed in the past. The thesis provides comprehensive information on the distribution and morphology of mostly relict patterned ground and rock glaciers in the High Sudetes Mts. and in the Western and High Tatra Mts., respectively, which are the most widespread permafrost features that occur in these Central European mountain ranges situated north of the Alps. It shows that the landforms are closely related to increased severity of climates and/or sparser vegetation at higher elevations and as such they attest to the environmental conditions, which prevailed there towards the end of the Last Glacial Period to the early Holocene, but also to their current states. Similar elevation trends in the pattern morphology are also documented for...
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Měření půdní vlhkosti metodou EIS a teplotní stratifikace půdy v oblastech Khan Khentii strictly protected area a Khowsgol lake v Mongolsku
Sobotka, Milan
In July 2014, the Strictly Protected Area of Khan Khentii and Lake Khowsgol in Mongolia carried out moisture and soil temperature measurements in July 2014 to determine the link between these variables and permafrost. Measurement of soil moisture was performed by EIS (electrical impedance spectrometry). A total of 146 measurements were performed and 49 soil probes were digested. It is always measured in the A and B soil horizons. Measurements up to exceptions did not exceed 30 cm in depth with respect to the content of the skeleton whose skeletal content increased. The direct relationship of permafrost to thermal stratification of soil horizons has been demonstrated. The occurrence of permafrost up to 150 cm from the first measurement was characterized by a difference in temperature between the steps of up to 2 °C. In the case of permafrost deeper, the transition between the measuring steps was smoother, on average by 0.6 °C. By measuring the soil moisture Found by the highest average soil moisture at the nearest tenth, Goricho. Abnormally high soil moisture at this site may be due to the growth of the active layer of permafrost in the primary phase of its melting in the severe anthropogenic damage to the Gorkhy-Terelch National Park landscape.
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Morphology of thermal-contraction-crack features and their pattern
Dufek, Jaroslav ; Křížek, Marek (advisor) ; Roman, Matěj (referee)
This bachelor thesis deals with phenomenon of periglacial landscape of continuos permafrost such as thermal-conctraction-crack polygons and forms of their secondary infill - ice, sand, soil and composite-wedge pseudomorphs. Upper Pleistocene thermal-conctraction-crack polygons are located in mid-latitudes all across the Europe. Most common geometry shapes of these polygons are orthogonal and hexagonal patterns. Pseudomorphs are commonly situated in areas of lowlands, river terraces, floodplains on slopes with angle up to 4ř. Their distribution is closely associated with the maximum extent of past permafrost during the last glacial episode (~17-25 ka BP). This pleistocene phase is known as last periglacial maximum (LPM; Vandenberghe et al. 2014). Creation of ice-wedges is primarily bound to present continuous permafrost, which the southernmost Pleistocene limit in Europe has been established to 47ř N (Black 1976, Vandenberghe et al. 2014). However, some research suggest, that with favorable local conditions, ice-wedges can develop also in arid climate and discontinuous permafrost zone and they can occur together with sand-wedges (Kasse 1998). It was also found that cold arid climate is not the only factor for sand wedge development, but great importance has also local variability of microrelief such...
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Quantification of specific microbial functional guilds in Arctic permafrost soil
WALTER, Deborah
The quantity of specific bacterial and archaeal groups were determined in permafrost soils. The selected groups were quantified by quantitative polymerase chain reaction (qPCR) of specific genes: total archaea (16SrRNA gene), methanogenic archaea (mcrA gene), nitrogen fixators (nifH gene) and denitrifiers (nosZ gene). The quantities of these groups were compared between different soil horizons and furthermore correlations between the quantity of gene copies and basic soil parameters were computed.
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Izolace specifických druhů bakterií z permafrostu
RODOVÁ, Ivana
This work is mainly focused on the isolation and characterization of bacteria from Arctic permafrost, which can utilize aliphatic and aromatic carbohydrates. Previous work showed that mainly Proteobacteria and Actinobacteria dominate in permafrost soils. Therefore, this work was mainly focused on these two groups. Aliphatic and aromatic carbohydrates are utilized by very specialized group of bacteria which use unique enzymatic apparatus. Thanks to this ability these bacteria play crucial role in carbon cycle in specific cryoturbated soil horizons typical for Arctic permafrost soils, where high amount of aliphatic and aromatic compounds was confirmed. These pure isolates may also be used in treating contaminated areas by oil or other pollutants.
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Spatial distribution and morphology of polygonal nets of frost and ice wedges pseudomorphs in the Czech Republic
Vohradský, Lukáš ; Křížek, Marek (advisor) ; Treml, Václav (referee)
Ice and frost wedges are a geomorphological phenomenon which is directly related to periglacial environment and permafrost (Murton, 2007). The presence of permafrost in the territory of the Czech Republic in the Pleistocene period is directly proven by polygonal nets of ice and frost wedge pseudomorphs, which are clearly visible in some remote sensing images. Among others, they can also be used as indicators of paleoenvironmental conditions for the period in which their recent forms originated and developed and for the period of their secondary infilling (Sekyra, 1958). The present thesis focuses on the spatial distribution and morphology of polygonal nets of ice and frost wedge pseudomorphs which were created in the territory of the Czech Republic at the end of Pleistocene and the beginning of Holocene. The analysis of the spatial distribution of polygonal nets was carried out with freely available remote sensing images provided by the GoogleEarth Pro application (Google Inc., 2011). The number of locations with a potential presence of pseudomorphs was 629. Out of these, 49 were subjected to a morphometric analysis of polygonal nets and their corresponding landscape. Statistical data analysis showed that the described polygonal nets of ice and frost wedge pseudomorphs in the territory of the Czech Republic...
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Morphological feattures of ice wedge polygons in arctic zone.
Kysilka, Tomáš ; Křížek, Marek (advisor) ; Treml, Václav (referee)
Morphological features of ice wedge polygons in arctic zone Abstract This bachelor thesis deals with the subject of ice-wedge polygons including theirs morphological characteristics and conditions prerequisite for their creation. The paper states the conditions which allow and inhibit frost cracking of the ground. First part presents the conclusions of scientific literature published on the topic of permafrost, frost cracking, ice- wedges and ice-wedge polygons. Consequently the paper discusses the relation of ice-wedge polygons morphology to climate and lithology. Further the thesis analyzes morphological characteristics of ice-wedge polygonal net localized at southwest part of Banks Island, Canadian Arctic Archipelago. Acquired data and conclusions are confronted with published periglacial literature. Keywords: ice-wedge, ice-wedge polygons, frost cracking, permafrost, Banks Island, arctic zone
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