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Methods of study habitats and microhabitats preferences of freshwater fishes of Central Europe
Žák, Jakub ; Švátora, Miroslav (advisor) ; Drozd, Bořek (referee)
Small streams are a common habitat in Central Europe with unstable, rapidly-changing conditions. We can examine habitats on three different scales: microhabitat, mesohabitat and macrohabitat. Habitat preferences were among the fields of interest of Antonín Frič as he tried to describe the changing gradient of fish assemblages from source to the river's mouth on the macrohabitat scale. Habitat preferences are examined from a spatial point of view (substrate, depth, shelter), temporal point of view (season, day/night), biotic point of view (interspecies and intraspecies competition) and abiotic point of view (dissolved chemicals, velocity). For obtaining data of good quality, it is necessary to choose the right location and select the opti- mal strategy of examining fish assemblages (e.g. electrofishing, radiotelemetry, cameras). All variables which can affect habitat preferences in fish are measured. Multivariate statistical methods (e.g. PCA, RDA, CCA, CA) are used for evaluation of obtained datasets. Currently, we live in a fast developing period of this scientific area because of the need of evaluation of the human impact on freshwater biotope. The aim of this bachelor thesis is to introduce variables which influence habitat pref- erences of fish, to propose a modern review of methods commonly...
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Habitat preferences of the members of the family Chydoridae (Crustacea, Cladocera)
Zimová, Tereza ; Sacherová, Veronika (advisor) ; Šorf, Michal (referee)
This thesis is a literature review of ecological niche of some species of Cladoceran family Chydoridae. The aim of this work is to summarize the knowledge about the occurrence of species in various types of environments and what are their preferences or see which factors are limiting for them. This work is focused on the type of habitats in which they are found, the trophic state of water and pH. It also mentions to a lesser extent environmental factors such as concentration of calcium and water depth, which might also influence the niche choice of these species. Species can be divided into opportunists with a wide niche and specialists with a narrow one, yet a large proportion of species have a wide tolerance to most environmental factors. Key words: Chydorids, niche, habitat, macrophytes, open water, pH, trophic state, depth, calcium
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Methods of study habitats and microhabitats preferences of freshwater fishes of Central Europe
Žák, Jakub ; Švátora, Miroslav (advisor) ; Drozd, Bořek (referee)
Small streams are a common habitat in Central Europe with unstable, rapidly-changing conditions. We can examine habitats on three different scales: microhabitat, mesohabitat and macrohabitat. Habitat preferences were among the fields of interest of Antonín Frič as he tried to describe the changing gradient of fish assemblages from source to the river's mouth on the macrohabitat scale. Habitat preferences are examined from a spatial point of view (substrate, depth, shelter), temporal point of view (season, day/night), biotic point of view (interspecies and intraspecies competition) and abiotic point of view (dissolved chemicals, velocity). For obtaining data of good quality, it is necessary to choose the right location and select the opti- mal strategy of examining fish assemblages (e.g. electrofishing, radiotelemetry, cameras). All variables which can affect habitat preferences in fish are measured. Multivariate statistical methods (e.g. PCA, RDA, CCA, CA) are used for evaluation of obtained datasets. Currently, we live in a fast developing period of this scientific area because of the need of evaluation of the human impact on freshwater biotope. The aim of this bachelor thesis is to introduce variables which influence habitat pref- erences of fish, to propose a modern review of methods commonly...
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Functional connectivity and quality of biocentres in the border area of Šumava and Bavarian Forest National Parks
EFFENBERKOVÁ, Lenka
The Bohemian Forest, a mountain range located in Central Europe on the border between the Czech Republic, Germany and Austria, has many well-known qualities. The areas of Modravské slatě moors and Trojmezná, are considered to be the most valuable biocenters in the Czech part of the Bohemian Forest. This Master thesis confirms the quality of these areas in a transboundary context Natura 2000 habitats and their representativeness. A new transboundary (European) biocentre is proposed and its importance for several species is discussed.
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