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Spatial distribution and morphological analysis of river islands in the Czech Republic
Růžičková, Veronika ; Křížek, Marek (advisor) ; Kalvoda, Jan (referee)
The topic of this thesis is spatial distribution of mid-channel bars on Czech rivers. Its aim is to describe the laws of their morphology and distribution in the river channel using remote analysis of aerial photographs. Czech islands originate in places where the flow slows down, mainly in bends and around obstacles in the channel. Their main axis is in the most cases parallel to the course of the streamline. The width of the channel and the presence of vegetation have an undeniable effect on the size of the islands. The presence and morphological characteristics of the river islands also reflect human intervention in the course of the river channel, where does it matter whether it is an artificial channel with hardened banks or a natural-looking one. Key words: fluvial geomorphology, mid-channel bars, river islands, sedimentation, Czech rivers
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Geomorphological evolution of the Hřebeny Ridge in Brdy
Soukupová, Lenka ; Kalvoda, Jan (advisor) ; Balatka, Břetislav (referee)
4 ABSTRACT The main aims of presented study about the geomorphology of the Hřebeny Ridge in Brdy Mts. are 1/ the documentation of landform patterns and 2/ the description of main stages of the relief evolution. In opening chapters of the paper, the natural envi- ronments of the Hřebeny Ridge and Brdy Mts. as a whole are characterized. In the fol- lowing chapter, a reflection of the geological structure in present-day landforms is de- scribed. Landform analysis of the studied region related to climate-morphogenetic pro- cesses is presented and detailed geomorphological map (1:10 000) is enclosed. Final part of the study is concerned with main stages of the landform evolution of the Hřebeny Ridge. Field observation and its geomorphological interpretation are compared with earlier regional studies. The presented paper demonstrates that landforms of the Hřebeny Ridge in Brdy Mts. are determined by the geological structure, e.g. by the geomorphological resistance of rocks. Present-day landforms of the Hřebeny Ridge evolved in the Quaternary. Im- portant processes of the landform evolution of the region are connected with the origin of deep river valleys. The landform patterns of the ridge part and its slopes are essential- ly influenced by the Pleistocene cryogenic weathering of rocks as well as very intensive...
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Evaluation of physical-geographical research of the High Tatra Mts in the period 1969 - 2008
Jurdík, Michal ; Kalvoda, Jan (advisor) ; Engel, Zbyněk (referee)
This bachelor thesis deals with physical-geographical researches about High Tatra Mts published in 1969 - 2008. It describes mountains within it's geomorphological, hydrological, climate, soil and other features. I have discussed the late and novel information. It highlithed the points were the knowledge diverged. High Tatra Mts. build an exclusive complex of landscape natural components. Lots of landform factors in small area and vertical zonation with variable characteristics makes this area a good model for geographical studies. Key words: physical geography, High Tatra Mts.
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Glacial modelation of cirques and stratigraphy of moraines in the High Tatras
Mida, Peter ; Křížek, Marek (advisor) ; Kalvoda, Jan (referee)
The submitted diploma thesis is concerned with the geomorphological analysis of specific landforms in the High Tatras which are the result of its Quaternary mountain glaciation. The traces of the last three glacials (Mindel, Riss and Würm) are well documented in the studied area. The presence of the Early Pleistocene glaciations (Biber, Donau, Günz) is more difficult to prove. The aim of this thesis is 1) to define the rate of glacial shaping of glacial erosional landforms - cirques; 2) to determine the number of glacials or stadial oscillations of glaciers on the basis of relative dating of moraines during the Last Glaciation. A total number of 122 cirques were analysed. Cirques were classified as follows: simple cirque, termination cirque, stepped cirque and highest cirque. Morphometric characteristics that were implemented are consistent with other studies (e. g. Federici & Spagnollo, 2004, García-Ruiz et al., 2000). A degree of glacial overdeepening of a cirque was quantified by use of k coefficient which is derived from k-curve (sensu Haynes, 1968). Value of k coefficient depends on profile location and cirque headwall foot location. Range of values of k coefficient for the cirques in High Tatras is between 0,503 and 1,951. Based on morphometric analysis the northern mountainside cirques are...
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Natural environment of the Moon
Lulák, Martin ; Kalvoda, Jan (advisor) ; Křížek, Marek (referee)
This presented bachelor paper aims to describe the environment of the Moon based on accessible publications. It is especialy focused on the morphology of the most striking lunar landforms, as well as the origin of the Moon and its geological evolution, description of formation and characteristics of lunar regolith and effects of space weathering on lunar landforms. The second part of the paper is aimed at the morphological description of large impact craters - Tycho and Plato. Owing to the different age of these selected complex craters, it is possible by correlation of their patterns to demonstrate effects of main processes changing the Moon's surface. Key words: Moon, impactor, impact craters, space weathering, multi-ring impact basin, regolith, selenography, Tycho, Plato
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Response of selected rivers of the Bohemian Massif to lithological and structural conditions
Flašar, Jan ; Nývlt, Daniel (advisor) ; Kalvoda, Jan (referee)
Three groups of streams were selected in the area of the Bohemian Massif: the Berounka river with its source streams; the Vltava river with its tributaries the Malše and the Lužnice; the Labe river with its tributaries the Cidlina, the Bystřice and the Javorka. The lithological and tectonical influences to several parameters of the streams were studied. These parameters include: stream gradient, orientation of the stream and sinuosity of the stream. Data were obtained from digital elevation models, aerial photographs, topographical and geological maps. The longitudinal profiles of the streams (in the combination with geological cross-sections), the SL indexes and the gradient/sinuosity graphs were created on the basis of the obtained data. These tools were used for evaluation of the influence of lithology and the tectonics to the streams. The evolution of the streams and the stream-groups was evaluated and compared as well. A strong influence of lithology on the stream gradient was found on most of the analysed streams. The tectonic situation, on the contrary, had strong influence on the orientation of the streams, especially in the resistant rocks. Also, there were selected areas, where was a higher probability of quaternary vertical movements influencing the streams (mountainous areas of the Novohradské...
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Steppe or woodland? Ecological Conditions of Formation and Evolution of Chernozems in Central Europe
Vysloužilová, Barbora ; Šefrna, Luděk (advisor) ; Kalvoda, Jan (referee) ; Havlicek, Elena (referee)
Chernozem became the crucial soil for the beginnings of soil science through the work of Dokuchaev from 1883. Since then the genesis of chernozems in Central Europe has raised many questions among soil scientists, botanists and paleo-environmentalists. While in Eastern Europe chernozems have been described as zonal soils, that are typical for continental steppe and forest-steppe areas, there are areas in Central Europe which are predisposed by their climatic characteristics to the presence of woodlands. The goal of this dissertation is to enrich the discussion about the genesis of chernozems by restoring the environmental conditions that were prevalent during the formation of chernozem soils in Central Europe. Chernozems are usually developed on loess with a very thick and dark organic surface which passes directly to a calcareous horizon. The organic matter underwent a polymerization in dependence on climate contrasts. However, in Central Europe, the climatic characteristics of the areas of chernozems are a bit different. These chernozems are supposed to have been formed under the climatic conditions that dominated Central Europe during the Late Glacial and the Early Holocene. The climatic nuances may contribute to the explanation of the differences in distribution of chernozems ("drier") and...
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