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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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Freeze-thaw processes, temperature and moisture trends in earth hummocks
Kodríková, Anna ; Křížek, Marek (advisor) ; Treml, Václav (referee)
Earth hummocks are nonsorted patterned ground types. This thesis is primary focused on the study of temperature regime particularly during freeze-thaw process and also on factors that affect its non-uniformity. Secondary, it refers to the relation between temperature and moisture regime, morphometric characteristics of earth hummocks and their geographical expansion in the world. The information from the literature search is applied to the results from temperature and moisture measurements of the earth hummocks in depths 5 - 40 cm in the Hrubý Jeseník Mountains - Keprník peak in 2005 - 2010. The results show that many factors affect the non-uniformity of temperature regime in different parts of earth hummocks. The most important of them are: the shape of the earth hummock, the aspect orientation, the distribution and the height of snow cover, the wind exposure and the presence of vegetation. There is an interaction between the soil moisture content and the temperature regime, and they are mutually affected. The obtained results from the Keprník study area are compared with the literature data about the earth hummocks in the world. Key words: patterned ground, earth hummock, temperature regime, moisture, regelation, Keprník peak, Hrubý Jeseník Mountains
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Thermal and moisture regime of patterned ground in the High Tatras
Pechačová, Blanka ; Křížek, Marek (advisor) ; Engel, Zbyněk (referee)
6 ABSTRACT Thermal and moisture regime of patterned ground is closely associated with the presence of the regelation phenomenon. Generally, the regelation includes all processes leading to the water freeze-thaw alternations in soil or bedrock. As a result of cyclic freezing and thawing of soil water under specific conditions, processes, such a moisture migration, ice segregation or frost heaving, operate. Termal and moisture regime is the main factor of these processes and consequentely, of the patterned ground formation. The submited diploma thesis is concerned with thermal and moisture regime of patterned ground in the High Tatras. The main aims of the thesis was to characterize thermal and moisture regime of patterned ground, to evaluate and confront the patterned ground regelation activity depending on the diverse soil depths and different types of the patterned ground and to evaluate the soil temperature relationship to the air temperatures, soil moisture content and the water level regime of the nearest lakes. The partial purpose of the thesis was to assess the applicability of different methods of the regelation cycle determination based on the soil temperature measurements. During the study period 2007 - 2012 the regelation activity of sorted paterned ground (Hincove oká, Lúčne sedlo and Skalnaté...
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Regelation of patterned ground in the High Tatras.
Pechačová, Blanka ; Křížek, Marek (advisor) ; Voják, Karel (referee)
Regelation (freeze-thaw cycles) is the collective term used for a process of alternate freezing and thawing of water and solutions into the soil or bedrock. The series of geomorphological and pedological processes such as migration of soil water, formation of segregated ice or frost heaving, is connected with regelation. Condition of freezing-thawing process is a phase transition of water that leads to an important phenomenon - a release or consumption of latent heat. This phenomenon can be observed from the data obtained by measuring the temperature in the soil profile. In the present bachelor thesis, here are investigated sites of sorted patterned ground (Hincovo pleso, Lučné sedlo) and earth hummocks (Kopské sedlo) in the High Tatras for the purposes of the study regelation process. In addition to detailed description of the physical-geomorphological processes associated with phase changes of water in patterned groud, the main aim of the thesis is to set regelation cycles and their characteristics using different methods for determination of regelation on the basis of temperature measurements in patterned groug of the foregoing locations. The results indicate differences in regelation in the individual shapes within the locations, among the sites, but also between different types of patterned groud -...
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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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Spatial and morphometric features of thermal contraction crack polygons on Mars
Žížalová, Ivana ; Křížek, Marek (advisor) ; Brož, Petr (referee)
The aim of this thesis is to analyze zonality of the thermal contraction crack polygons on the surface of Mars. Their morphology and its variation are analyzed in relation to the latitude of Mars. For spatial and morphological analysis were selected 64 images from the HiRISE (Mars Reconnaissance Orbiter) polychromatic camera dataset, images are covering the bandwidths proportionally. Images were first visually analyzed using HiView. 258 areas containing the thermal contraction crack polygons (with total area of 1184 km2 ) and 1036 well developed thermal contraction crack polygons were further vectorized using ArcMap. The thermal contraction crack polygons were found in every searched latitude which proves the ubiquity of permafrost. The largest amount of the thermal contraction crack polygons have been found in latitudes ±60ř and 45ř. In these latitudes were also found the largest and probably the deepest thermal contraction crack polygons (average length ranges from 42,1 - 73,6 m). The smallest polygons (average length 7,7 m) were found around the equator. "Altitude" has no effect on the spread of the thermal contraction crack polygons on Mars; however it has the effect on its morphology. The most widespread are pentagonal polygons, which occur mainly in the southern hemisphere. The next most...
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Thermal and moisture regime of patterned ground in the High Tatras
Pechačová, Blanka ; Křížek, Marek (advisor) ; Engel, Zbyněk (referee)
6 ABSTRACT Thermal and moisture regime of patterned ground is closely associated with the presence of the regelation phenomenon. Generally, the regelation includes all processes leading to the water freeze-thaw alternations in soil or bedrock. As a result of cyclic freezing and thawing of soil water under specific conditions, processes, such a moisture migration, ice segregation or frost heaving, operate. Termal and moisture regime is the main factor of these processes and consequentely, of the patterned ground formation. The submited diploma thesis is concerned with thermal and moisture regime of patterned ground in the High Tatras. The main aims of the thesis was to characterize thermal and moisture regime of patterned ground, to evaluate and confront the patterned ground regelation activity depending on the diverse soil depths and different types of the patterned ground and to evaluate the soil temperature relationship to the air temperatures, soil moisture content and the water level regime of the nearest lakes. The partial purpose of the thesis was to assess the applicability of different methods of the regelation cycle determination based on the soil temperature measurements. During the study period 2007 - 2012 the regelation activity of sorted paterned ground (Hincove oká, Lúčne sedlo and Skalnaté...
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Recognition and classification of patterned ground polygons from remote sensing data
Kříž, Jan ; Potůčková, Markéta (advisor) ; Brodský, Lukáš (referee)
Recognition and classification of patterned ground polygons from remote sensing data Abstract The main objective of this thesis has been to prove the possibility of using object based image analysis classification for identification of the ice-wedge polygons and to find general method for their classification. The thesis contains a comparison of the object based and pixel based classification of the subject. The three classification rulesets for OBIA were developed on three test sites on Mars captured by HiRISE sensor. As a result, the general classification approach is suggested. The manually collected datasets, which are common in geomorphological research, were used as the reference sample. The OBIA classification provided better results in all three cases, whereas the pixel classification was valid in only one case. Another objective has been the automatization of the process of gaining information about morphometric characteristics of the ice-wedge polygons and the subsequent classification of the polygons. Within the scope of the process were developed methods for creating polygonal network and specified parameters of those methods. Several toolboxes for the ArcGIS software were prepared and they are part of the results of the thesis. Keywords: patterned ground, ice-wedge polygons, remote sensing,...
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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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Regelation of patterned ground in the High Tatras.
Pechačová, Blanka ; Křížek, Marek (advisor) ; Voják, Karel (referee)
Regelation (freeze-thaw cycles) is the collective term used for a process of alternate freezing and thawing of water and solutions into the soil or bedrock. The series of geomorphological and pedological processes such as migration of soil water, formation of segregated ice or frost heaving, is connected with regelation. Condition of freezing-thawing process is a phase transition of water that leads to an important phenomenon - a release or consumption of latent heat. This phenomenon can be observed from the data obtained by measuring the temperature in the soil profile. In the present bachelor thesis, here are investigated sites of sorted patterned ground (Hincovo pleso, Lučné sedlo) and earth hummocks (Kopské sedlo) in the High Tatras for the purposes of the study regelation process. In addition to detailed description of the physical-geomorphological processes associated with phase changes of water in patterned groud, the main aim of the thesis is to set regelation cycles and their characteristics using different methods for determination of regelation on the basis of temperature measurements in patterned groug of the foregoing locations. The results indicate differences in regelation in the individual shapes within the locations, among the sites, but also between different types of patterned groud -...
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