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Study of pollen in situ of Cretaceous conifers based on selected examples
Ludvíková, Anastázie ; Kvaček, Jiří (advisor) ; Dašková, Jiřina (referee)
The review part of this thesis focuses on the synthesis of knowledge about male cones of Mesosoic conifers and their pollen based on selected examples from Upper Cretaceous of Europe. This thesis especially examines families Cheirolepidiaceae, Podocarpaceae, Araucariaceae and Cupressaceae. In this thesis the characteristics of these families are supplemented with a comparison to their recent genera. The main method described in this thesis is the study of pollen in situ due to the majority of these selected examples being preserved as compressions. The practical part of the thesis aims to taxonomically classify the fossilized male cones provided from the collections of the National Museum, originating from the Peruc-Korycany Formation locality of Pecínov. One of these cones was assigned to the genus Classostrobus associated with the conifer Frenelopsis alata (family Cheirolepidiaceae) based on the presence of in situ pollen genus Classopollis and the shape of its microsporophylls. Key words: Cretaceous, conifers, pollen in situ
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"Small carbonaceous fossils (SCFs)": state of art
Kovář, Vojtěch ; Fatka, Oldřich (advisor) ; Dašková, Jiřina (referee)
The thesis deals with the problematics of Small Carbonaceous Fossils (SCF). In the first part of the thesis the term SCF is defined and the presentation of the main palynological approaches used for extraction of SCFs follows, together with an explanation of preservation processes of non-biomineralized organic structures in sediments. The explanation of significance for palaeontology and related disciplines is discussed. The main part of the thesis constitutes of descriptions of the individual published SCFs from the late Ediacaran up to the Devonian, together with stratigraphic context and lithology of the published material. The list of taxa, that were possible to identify among obtained SCF material, is included. All the localities of Phanerozoic age are further plotted into paleogeographic maps corresponding with the appropriate periods. The broad scope of SCF's paleogeographic provenance and the possibility of extraction of SCF from a wide spectrum of lithologies, deposited in various sedimentary environments is discussed and the potential of further studies of SCFs is outlined. Key words: organic microfossils and macrofossils, early Paleozoic, taphonomy, palynological preparation methods
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"Small carbonaceous fossils (SCFs)": state of art
Kovář, Vojtěch ; Fatka, Oldřich (advisor) ; Dašková, Jiřina (referee)
The thesis deals with the problematics of Small Carbonaceous Fossils (SCF). In the first part of the thesis the term SCF is defined and the presentation of the main palynological approaches used for extraction of SCFs follows, together with an explanation of preservation processes of non-biomineralized organic structures in sediments. The explanation of significance for palaeontology and related disciplines is discussed. The main part of the thesis constitutes of descriptions of the individual published SCFs from the late Ediacaran up to the Devonian, together with stratigraphic context and lithology of the published material. The list of taxa, that were possible to identify among obtained SCF material, is included. All the localities of Phanerozoic age are further plotted into paleogeographic maps corresponding with the appropriate periods. The broad scope of SCF's paleogeographic provenance and the possibility of extraction of SCF from a wide spectrum of lithologies, deposited in various sedimentary environments is discussed and the potential of further studies of SCFs is outlined. Key words: organic microfossils and macrofossils, early Paleozoic, taphonomy, palynological preparation methods
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Aspects of the high latitude environments in Cretaceous and Paleogene with special respect to land plants
Chernomorets, Oleksandra ; Sakala, Jakub (advisor) ; Dašková, Jiřina (referee)
This work is focused on the problematics of high latitudes in Cretaceous and Paleogene. The introduction describes and defines high latitude regions as well as their main characteristics nowadays. This allows one to achieve a better understanding of the substantial differences of these regions nowadays and in the geological past. The work itself then provides a brief description of the palaeographic position of the Arctic and Antarctic regions, their palaeoclimatic situations, organisms inhabiting their terrestrial and marine environments and their adaptation mechanisms. Further, a more detailed review of the land plants is presented. The last part is dedicated to the specific survival strategies of the land plants in the polar regions during the warm geological periods. On the basis of the studied literature, this work attempts to answer the questions: which strategy for adaptation to the high latitudes was used by the plants and whether being evergreen or deciduous was more effective on survival during the long and relatively warm polar nights. In conclusion, the relevance of the research of high latitude regions during the Cretaceous and Paleogene greenhouse type of climate is introduced in relation to the possible future consequences of the global warming. Key words: Cretaceous, Paleogene, land...
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