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Genesis of granite caves in the Krkonoše Mts.
Tomíček, Jiří ; Engel, Zbyněk (advisor) ; Hartvich, Filip (referee)
In the Giant Mountains have been recorded 16 granite caves in total, they can be classified into 4 morphogenetic groups: crevice caves, crevice - collapse caves, talus caves and rockwall niches. The spatial distribution of caves is very irregular - 13 caves in the Pogórze Karkonoskie and 3 in the Giant Mts. ridge. Caves, associated with the rock blocks movements (crevice, crevice - collapse, talus caves), have formed in periglacial conditions by cryogenic and gravitational processes. Rockwall niches have formed by selective weathering along horizontal fractures. The most suitable granite of Giant Mountains is coarse - grained porphyric type, which has an irregular primary joint system and is less resistant to selective weathering. The investigation of a present - day development of Krakonošova klenotnice and Lomená caves in Pančavská jáma cirque should be focused on monitoring of recent rock blocks movements and on relative dating of joint planes.
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Land-cover changes and climatic settings of the Úpské rašeliniště mire
Hejda, Tomáš ; Treml, Václav (advisor) ; Šefrna, Luděk (referee)
Mires, or wetlands, are very important habitats, ecosystems, as well as relict and recent reserves. The object of the study of mires is focused on morphological, hydrological and chemical characteristics as they are more discussed globally due to climate change. The present thesis deals with the characteristics of mires on a global scale, which are used in literature and make up their classification. The classification of mires is also addressed on the Czech scale with a focus on the Western High Sudetes. Mires of the Giant Mts. were analyzed according to climate conditions with a focus on the dynamics of land cover areas of Úpské rašeliniště mire and subsequently compared with Scandinavian mires. A particularly strong dependence on the Aapa type can be stated from the analysis. The vegetation above the alpine timberline primarily consisting of dwarf pines (Pinus mugo) and spruce families showed a substantial increase with respect to the impacts of climate fluctuations in the recorded period in Eastern High Giant Mts. Key words: mires, classification, Giant Mts., climate, vegetation change
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Land-cover changes and climatic settings of the Úpské rašeliniště mire
Hejda, Tomáš ; Treml, Václav (advisor) ; Šefrna, Luděk (referee)
Mires, or wetlands, are very important habitats, ecosystems, as well as relict and recent reserves. The object of the study of mires is focused on morphological, hydrological and chemical characteristics as they are more discussed globally due to climate change. The present thesis deals with the characteristics of mires on a global scale, which are used in literature and make up their classification. The classification of mires is also addressed on the Czech scale with a focus on the Western High Sudetes. Mires of the Giant Mts. were analyzed according to climate conditions with a focus on the dynamics of land cover areas of Úpské rašeliniště mire and subsequently compared with Scandinavian mires. A particularly strong dependence on the Aapa type can be stated from the analysis. The vegetation above the alpine timberline primarily consisting of dwarf pines (Pinus mugo) and spruce families showed a substantial increase with respect to the impacts of climate fluctuations in the recorded period in Eastern High Giant Mts. Key words: mires, classification, Giant Mts., climate, vegetation change
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Dendrochronological dating of the past avalanche events in the Krkonose Mts.
Tumajer, Jan ; Treml, Václav (advisor) ; Kociánová, Milena (referee)
Avalanches are important natural processes which shape the character of large mountainous areas. The reconstruction of their history has been performed on avalanche tracks in the Důl Bílého Labe Valley, Krkonoše Mts. through application of dendrogeomorphological methods. In total 101 trees from the area of 5 avalanche tracks were cored or cross-sectioned, which helped to identify 1253 growth disturbances (abrupt growth suppressions or releases, increases in tree-ring eccentricity, traumatic resin ducts, reaction wood, callus or determination of the tree death). The analysis spanning period from the 1859 led to the identification of 40 avalanche events, which prolong and complement written evidences of avalanche falls (avalanche cadastre). However, because of limitations of dendrogeomorphology (especially impossibility of dating of small events), these results have character of only minimal number of events. Strong influence of monthly snow melting and snow accumulation on initiation of events was pointed out through the statistical analysis of snowpack changes in relation to the reconstructed avalanche activity. Two main possible natural reasons for avalanche activity initiation were identified - vast spring snow melting and loading with fresh snow. The analysis demonstrates the potential of...
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Genesis of granite caves in the Krkonoše Mts.
Tomíček, Jiří ; Engel, Zbyněk (advisor) ; Hartvich, Filip (referee)
In the Giant Mountains have been recorded 16 granite caves in total, they can be classified into 4 morphogenetic groups: crevice caves, crevice - collapse caves, talus caves and rockwall niches. The spatial distribution of caves is very irregular - 13 caves in the Pogórze Karkonoskie and 3 in the Giant Mts. ridge. Caves, associated with the rock blocks movements (crevice, crevice - collapse, talus caves), have formed in periglacial conditions by cryogenic and gravitational processes. Rockwall niches have formed by selective weathering along horizontal fractures. The most suitable granite of Giant Mountains is coarse - grained porphyric type, which has an irregular primary joint system and is less resistant to selective weathering. The investigation of a present - day development of Krakonošova klenotnice and Lomená caves in Pančavská jáma cirque should be focused on monitoring of recent rock blocks movements and on relative dating of joint planes.
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