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Genus Apodemus (Mammalia: Rodentia) in the Quaternary fossil record of Central Europe.
Knitlová, Markéta
Wood mice of the genus Apodemus rank among the most common extant mammals throughout Europe. A history of its species and their distributional ranges is to be looked upon as a serious topic relevant also for general concepts on current setting of European biotic diversity. Nevertheless, despite several phylogeographic studies on that subject and a rich fossil record of the genus, many details of that issue remains only very poorly comprehended. This state is essentially caused by enormous complications with phenotype discrimination of individual species, their extensive variation and broad between-species overlaps in all phenotype traits. The present project was intended to establish the techniques enabling reliable species identification applicable to fragmentary fossil materials and to use them for retrieving information on range dynamics and phylogenetic history of individual species during the Quaternary past. It begun with detailed morphometric analyses of extant populations, using the characters available in fossils, and with establishing a concept of alternative parataxonomic classification covering the complete phenotype span of the genus. The respective techniques were applied onto an extensive set of well-dated records from the Late Pleistocene-Holocene sedimentary series from diverse...
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Primary and secondary magnetic fabric as a tool for paleoenvironmental reconstruction
Žatecká, Michaela ; Chadima, Martin (advisor) ; Pruner, Petr (referee)
This diploma thesis deals with the research of primary and secondary magnetic fabric of aeolian loess sediments and paleosols on the cross-section temporary cropping out during the construction work in Prague 6. Magnetic enrichment - and the formation of magnetic nanoparticles in soil horizons - occurs during pedogenesis in warmer interglacials periods. The aim of this work is the interpretation of the paleoenvironment, weathering and pedogenic processes, by measuring the magnetic properties of sediments. Magnetic susceptibility, frequency-dependent magnetic susceptibility, anhysteresis remanent magnetization and natural remanent magnetization are used to detect the increased occurrence of magnetic particles, which indicate these pedogenic processes. The most developed paleosol horizon within the cross-section was the horizon of black soil and subsoil brown soil. Small signs of pedogenesis were revealed in the upper and lower loess part of the section. The magnetic fabric of loess, measured by means of anisotropy of magnetic susceptibility, reflects secondary sedimentary processes. This involves the displacement of clastic particles by flowing water and the redeposition of the material along the slope. The direction of movement of these sediments corresponds to the current geomorphology of the...
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Western Carpathians as diversity hotspot during the Quaternary climatic cycle
Kubíková, Kateřina ; Juřičková, Lucie (advisor) ; Horáček, Ivan (referee)
In the context of the entire Europe, the Western Carpathians is a unique area of priceless biological significance. Topological complexity, together with significant climatic and edaphic variability, is reflected in the high habitat heterogeneity and has enabled the survival of a large number of species in this area during the Quaternary climatic cycle. The Western Carpathians thus represents one of the most important glacial as well as interglacial refugium in Europe. The result of these environmental variables and the unique history of this region is an enormous species diversity, a high degree of endemism and the occurrence of many glacial relics. This bachelor's thesis contains a review of mainly zoological studies dealing with high biodiversity and degree of endemism in the Western Carpathians and its possible causes. The role of the Western Carpathians as an important Pleistocene refugium, its influence on other parts of Europe and the postglacial development of the area are discussed in individual chapters.
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Genus Apodemus (Mammalia: Rodentia) in the Quaternary fossil record of Central Europe.
Knitlová, Markéta
Wood mice of the genus Apodemus rank among the most common extant mammals throughout Europe. A history of its species and their distributional ranges is to be looked upon as a serious topic relevant also for general concepts on current setting of European biotic diversity. Nevertheless, despite several phylogeographic studies on that subject and a rich fossil record of the genus, many details of that issue remains only very poorly comprehended. This state is essentially caused by enormous complications with phenotype discrimination of individual species, their extensive variation and broad between-species overlaps in all phenotype traits. The present project was intended to establish the techniques enabling reliable species identification applicable to fragmentary fossil materials and to use them for retrieving information on range dynamics and phylogenetic history of individual species during the Quaternary past. It begun with detailed morphometric analyses of extant populations, using the characters available in fossils, and with establishing a concept of alternative parataxonomic classification covering the complete phenotype span of the genus. The respective techniques were applied onto an extensive set of well-dated records from the Late Pleistocene-Holocene sedimentary series from diverse...
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Application of environmental magnetic techniques in Quaternary sediment study
Žatecká, Michaela ; Kadlec, Jaroslav (advisor) ; Kletetschka, Günther (referee)
5 ABSTRACT: The Bachelor Thesis presents basic principles of the environmental magnetic methods and their applications in paleoenvironmental reconstructions from Quaternary sedimentary archives. Description of mineral and rock magnetic principles follows after an introductory sketch of historical development of the environmental magnetic topic. Next part of the thesis is focused on explanation of basic principles of the environmental magnetic methods and application magnetic history of the sedimentary rocks: namely different kinds of magnetic susceptibility, anisotropy of magnetic susceptibility, remanent magnetization and hysteretic parameters of the sediments. Application of the environmental magnetic methods enables interpretation of depositional and/or post- depositional history (e.g., directions of wind or water currents transporting clastic sediments) or intensity of geochemical weathering (connected with pedogenesis) which is directly controlled by climatic conditions and their changes. Examples of application of the environmental magnetic methods in paleoenvironmental research of the deep ocean, lacustrine and eolian natural archives are described in the final part of the thesis. Key words: environmental magnetism, paleoenvironmental reconstruction, sedimentary archives, Quaternary
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Genus Apodemus (Mammalia: Rodentia) in the Quaternary fossil record of Central Europe.
Knitlová, Markéta ; Horáček, Ivan (advisor) ; Macholán, Miloš (referee) ; Čermák, Stanislav (referee)
Wood mice of the genus Apodemus rank among the most common extant mammals throughout Europe. A history of its species and their distributional ranges is to be looked upon as a serious topic relevant also for general concepts on current setting of European biotic diversity. Nevertheless, despite several phylogeographic studies on that subject and a rich fossil record of the genus, many details of that issue remains only very poorly comprehended. This state is essentially caused by enormous complications with phenotype discrimination of individual species, their extensive variation and broad between-species overlaps in all phenotype traits. The present project was intended to establish the techniques enabling reliable species identification applicable to fragmentary fossil materials and to use them for retrieving information on range dynamics and phylogenetic history of individual species during the Quaternary past. It begun with detailed morphometric analyses of extant populations, using the characters available in fossils, and with establishing a concept of alternative parataxonomic classification covering the complete phenotype span of the genus. The respective techniques were applied onto an extensive set of well-dated records from the Late Pleistocene-Holocene sedimentary series from diverse...
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Palaeoecological reconstruction of Komořany Lake in Late Glacial based on diatom analysis
Poštulková, Anna ; Nedbalová, Linda (advisor) ; Tátosová, Jolana (referee)
Diatom analysis of basal part of profile PK-1-L contributes to multi-proxy research of former Lake Komořany. At this part of profile radiocarbon dating (dates sediments into Late Glacial and Early Holocene) and LOI (loss on ignition) had been conducted before, of which results have been utilized to more accurate interpretation of diatom analysis conclusions. Apart from diatom valves, presence of stomatocysts of Chrysophyceae has been observed. Having separated diatom valves from 32 sediment samples in intervals 0,4-0,6 cm, permanent preparates have been created. Concentration of valves in a gramme of dry sediment and relative abundance of diatom taxons in each sample have been investigated using light microscopy. In a half of samples subdominants and rare taxons have been observed separately to eliminate the interference from dominant taxons. Cluster analysis based on relative abundances of diatom taxons have been calculated and on its results have been subsequently determined three diatom accumulation zones (DAZ). Moreover trophic and saprobic indices have been calculated and levels of pH, conductivity and concentration of total phosphorus (TP) have been estimated by transfer functions. Even before beginning of Holocene the major shift in composition of diatom communities have happened, to the...
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Dating of uranium secondary minerals by the Thermal ionization mass spectrometry and α-spectroscopy
Roll, Michal ; Goliáš, Viktor (advisor) ; Strnad, Ladislav (referee)
SUMMARY: This paper is focused on analytical methods, specifically on thermal ionization mass spectrometry and alpha spectrometry; both methods are often use for dating of minerals or rocks. Goal of this paper is to compare these methods and decide which one is more suitable for dating of secondary uranium minerals. Methods are completely different and we judge them closely and take into account every fact not just technical skills as accuracy or speed which are in favor of thermal ionization mass spectrometry, but also device availability, price or published researches which are in favor of alpha spectrometry. There is also suggestion that both methods can cooperate and it seems as most effective way and there is another suggestion how studies a secondary uranium minerals.
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Diatoms of Quaternary Sediments from the Lake Komorany
Poštulková, Anna ; Rajdlová, Hana (advisor) ; Houfková, Petra (referee)
Diatoms are unicellular phototrophic organisms, whose siliceous frustules preserved in sediment have broad palaeolimnological application. Sediments of former Komořany Lake count among the richest Czech sediments in quaternary diatoms. This already destroyed locality is examinated in search and practical part of work. The search part contains characterization of diatoms and locality Komořany Lake. Diatoms are described in paleontological point of view, that is why the main attention is payed to morfology of frustule, their ecology and application in geological sciences. However, for complete image of this various group, the new pieces of knowledge about their taxonomy or evolution are not overlooked. The root of the work is summarization of accessible literature about Komořany Lake with special attention to research of diatoms. In practical part diatom valves were isolated from samples of sediment from profile PK-1-W, 18 long-lived sections were prepared and 6 of them were used for taxonomical determination. The 47 taxons of diatoms were found, 7 of them had not been included in work of Řeháková (1986). The synonymy of taxons are created in comparison with results of Řeháková (1986). From taken pictures are created 6 taxonomical plates. Key words: diatoms, Bacillariophyceae, Komořany Lake,...
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Sulphidic mineralization in the vicinity of the Bílina fault
Markes, Jan ; Zachariáš, Jiří (advisor) ; Goliáš, Viktor (referee)
The neoidic sulphide mineralization located in tertiary sediments of Lom Bílina in Bílina's fault is of hydrothermal origin. The sulphidic mineralization is associated with fault systems of Eger rift and temperature of fluid crystallization was about 50řC. The mineralization of Bílina's fault is rather monotonous, the marcasite and pyrite is mostly found without a trace elements. In the crystals were also registered zones with the contents of trace elements, especially As and Ni. The contents of As enriched precipitation zones were fluctuating from 0,2 to 5,4 wt. %, Ni enriched zones were ranged from 1,6 to 5,9 wt. %. The precipitation zones with increased As and Ni content were very thin, there were very short time intervals of As and Ni enriched fluids precipitation. In the marcasite crystals were also found the porous zones of clay mineral microinclusions. These zones showed higher content of Al and Si. There is high abundance of Fe-disulfides at Bílina's fault-dispersed in coal bed, or bonded to tectonic zone of the Bílina's fault. Pyrite and marcasite are dispersed in the coal bed and genetially aren't related to sulphides bonded to Bílina's fault.
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