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The importance of the Alps as a refugium in the Quarternary climate cycle with a focus on molluscs.
Gelnarová, Barbora ; Juřičková, Lucie (advisor) ; Coufal, Radovan (referee)
The Alps are a well-known glacial refugium, an important biodiversity hotspot and a centre of endemism for many species. This is due to their topological variability and the high heterogenity of their habitats, which thus provide a home for different species of organisms. In particular, the Eastern Alps represented an important glacial refugium and contributed to the survival of countless different species during the Quaternary climate cycle. This bachelor thesis is a literature review of mainly zoological publications that focus on the study of glacial refugia of terrestrial gastropods in the Alps. A large part of the thesis is devoted to the reasons for the considerable biodiversity, and especially the endemism, of this region. Another part deals with the postglacial dispersal spread of terrestrial gastropod species from their refugia. Key words: Alps, refugium, endemism, biodiversity, Quarternary, postglacional spread, molluscs, paleobiology
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Invertebrates indicative of seagrass meadows with a focus on molluscs.
Koucký, Václav ; Juřičková, Lucie (advisor) ; Petrusek, Adam (referee)
Seagrasses are angiosperms adapted to life in a marine environment, forming growths in coastal waters of all continents except Antarctica. Seagrass growths constitute ecologically important, highly productive ecosystems. Seagrasses are relatively rare in the fossil record due to their low fossilisation potential. To study distribution and other characteristics of this important ecosystem in the geological past, we need to be able to identify seagrass growths by using indirect indicators such as molluscs. From the available information, we can gather, that among molluscs there are several good seagrass indicators, but none are infallible and universally applicable. To infer seagrass growth presence in the absence of seagrass macrofossils we must utilize all information available at a given site.
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Molluscs as a new model system in molecular biology
Ber, Tobiáš ; Svoboda, Petr (advisor) ; Pergner, Jiří (referee)
Molluscs form the second largest animal phylum and are of great biological and economic significance. Their distinct evolutionary adaptations enabled them to inhabit a broad range of environments, with many of them invading new areas and becoming invasive pest species. Despite their importance, molluscan model systems have not received attention they deserve. In this bachelor thesis, I have reviewed the current state of molluscan model systems in molecular biology and analyzed their significance for more common use. From available data, it is apparent that the already established molluscan models are either marine or fresh-water, and therefore require more complex logistics and maintenance in order to set up a laboratory culture. To remedy the problem of aquaculture, the use of terrestrial gastropods was proposed. Here, I suggest that gastropods genus Deroceras have a good potential to become a new prominent molluscan model system in molecular biology.
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Succession of mollusk assemblages in quarries of Bohemian Karst
Kocurková, Alena ; Juřičková, Lucie (advisor) ; Horsáková, Veronika (referee)
Molluscan succession was studied in 18 abandoned limestone quarries of different age in Bohemian Karst. The number of species in studied quarries increases in the time. The less species were found in the oldest quarries. This trend was probably caused by habitat diversity decline although it is not conclusive. The best predictors of mollusk species composition are type of surrounding vegetation, light and the cover of tree layer. It is important to take into account correlations of the other environmental variables with light and the cover of tree layer. Compositions of mollusk assemblages of north and south-facing slopes differ, but these differences diminish with ongoing succession. Quarries represent suitable model sites for the study of succession.
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The influence of geology to the diversity of molluscan assemblages
Krajinčáková, Lucie Linda ; Juřičková, Lucie (advisor) ; Myšák, Jan (referee)
Molluscan populations are influenced by various factors of environment where they occur. In my work I am taking particular atention of soil properties, which are directly influenced by the geological substrate, and of course other factors which are with soil properties either directly or indirectly related. The important benchmarks are especially moisture, pH, calcium content and vegetation cover. This bachelor thesis also deals with utilization of calcium salts. Geological substrate is closely linked with the diversity and abundance of molluscan populations. Various pedochemical factors affect molluscan communities whether it is the amount of calcium in the soil or a pH value. In the past different authors found different dependencies between environmental factors, species composition and diversity of molluscan communities. Most of the studies were focused on very specific habitats and locations. In this thesis I tried to organize our knowledge about the specific effects of various environmental factors, especialy compositíon of geological substrate on malakofauna. Key words: Mollusca, Gastropoda, Geological substrate, diversity
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Metacommunities of the copepods, molluscs and ostracods in Kokořínsko pools on the longterm gradient
Tichá, Adéla ; Juračka, Petr Jan (advisor) ; Šorfová, Vanda (referee)
Re-creation and building new small freshwater habitats belong among the important management activities within the Protected Landscape Area Kokořínsko - Máchův kraj (Czech Republic) for almost two decades. These pools keep the water within the landscape and serve as the habitats for vulnerable species of amphibians and invertebrates, which I have studied within this thesis. Most studies focusing on studying metacommunities of small water bodies have been based on the data from one or two seasons, and thus completely neglect the development of composition of these metacommunities over longer periods of time. This thesis builds on previous research on the species composition of small ponds in the Kokořínsko Protected Landscape Area, which had been done in 2005 and 2006. In 2009 and 2017, sampling in the same ponds continued. I investigated the influence of spatial and environmental variables of individual ponds on the species composition of ostracods, copepods and molluscs in specific years and how has the representation of individual species changed among those years. With one exception, I have not observed any new incoming species of copepods and ostracods since 2006; the number of species had in fact decreased. In the case of molluscs, there was a significant exchange of species between individual...
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Short-term successions of mollusc assemblages of natural and anthropogenic habitats
Berková, Kateřina ; Juřičková, Lucie (advisor) ; Drvotová, Magda (referee)
This work compares the succession of mollusc communities of natural and anthropic habitats. It summarizes how mollusc assemblages of natural habitats change over time, if they are stable over time, and to what extent the natural succession of mollusc communities are affected by man. Mollusc communities of different habitats are subject of constant change. The mollusc succession of natural habitats was usually studied in deciduous forests. It leads to species-rich assemblages that do not change much in the short time-scale. The succession has also been studied at anthropic habitats such as quarries, urban habitats and castle ruins, where some species characteristic of particular habitat types or successive stages were identified. Key words: molluscs, succession, climax, disturbance, malacofauna
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Phylogenetic and ecological impact to the microstructures of mollusc shells
Nedvědová, Jana ; Juřičková, Lucie (advisor) ; Simon, Ondřej (referee)
This bachelor thesis summarizes the available information on microstructures of mollusc shells. The aim was to provide an overview of the different types of microstructures for specific specimens from different environments, as well as to obtain as much information as possible about the ecology of these animals. The first part summarizes the basic information on the shell formation. The following chapter summarizes known microstructure types of mollusc shells. Microstructures of molluscs living in terrestric, freshwater and marine environment are discussed. The influence of temperature changes on the shell microstructure of V. viviparus, the occurrence of vaterit within C. fluminea shells, the extreme environment of hydrothermal vents and cold seeps, as well as extreme temperatures on rocky shores, have been mentioned in more detail. The microstructures of related molluscs are compared with regard to ecology to determine whether the occurrence of microstructures in a particular group is given by the phylogeny of these animals, or if the changes in microstructures can be affected by different ecology. Key words: microstructures, molluscs shells, impact of phylogeny, impact of ecology, calcium carbonate, Mollusca, gastropods, bivalves
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Quaternary molluscs of Blanský les
Menšík, Jakub ; Juřičková, Lucie (advisor) ; Pokorný, Petr (referee)
Rich mollusc assemblages preserved in two profiles of fossiliferous sediment in the Blanský les area, provided the evidence about the Late Glacial and Holocene in this region, which is one of the most faunistically known areas of Central Europe. Findings of Quaternary faunas are very rare in Southern Bohemia, so these two soil profiles near Český Krumlov are so important for understanding the postglacial succession of Central Europe. The fossil mollusc assemblages showed an early appearance of forest species, which dominated both sites from the Boreal till Subboreal. Forest development in the Holocene Climatic Optimum reached a maximum, due to the absence of Neolithic man. Steppe species almost completely disappeared during this period. The development of the Young Holocene was linked to a decrease of the forest on the first site and the deforestation of the second site, due to a combination of a humidity decrease and human impact. In addition, some southern elements involved in the postglacial colonization of Central Europe, were found there. A few of them were found in a much older deposit than expected.
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Mollusca of European cities
Wolfová, Lucie ; Juřičková, Lucie (advisor) ; Drvotová, Magda (referee)
This bachelor thesis summarises knowledge of urban mollusc fauna. It shows cities as the centres of mollusc diversity in agricultural landscape but also as areas where high level of homogenization of mollusc assemblages were evidenced, therefore replacing native species, often endemics, with non-native and invasive species. Homogenization of urban mollusc fauna is especially caused by passive dispersal of species by human as well as to urban climate that is more favourable for spreading and surviving of non-native species, usually from warmer areas, than surrounding. There is mentioned another connected topic in this thesis - types of mollusc spreading. Furthermore, there is summarized which species of mollusc are typical for urban environment, what are the factors influencing the mollusc fauna and last but not least the methodological approaches for study of urban mollusc fauna.
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