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Long-distance plant dispersal in rivers
Krajníková, Anežka ; Fér, Tomáš (advisor) ; Hroudová, Zdenka (referee)
The aim of this bachelor thesis is to summarise present methods used in the research of dispersal river plants. Generally the dispersal of all kinds of plants which can be dispersed in water corridors, both dispersed in the water column and at the bottom of the channel. The bachelor thesis is a literatural rewiev. The main part of it is focused on direct methods of research of hydrochory and problems which could arise with individual methods. Each method is suitable for different set of circumstances and it is necessary to know in advance what kind of data we want to obtain. The direct methods includes: catching of the seeds directly from the stream - at one time, but repeatedly, or long term catching by using floating traps. Secondly we can use seed mimics or marked diasporas. The second part is focused on other factors which can influence long-distance plant dispersal in rivers. They include the degree to which are rivers regulated and the fluctuation off water level during years. The paper also includes a part which summarise the evidence on long distance dispersal of river plants. Powered by TCPDF (www.tcpdf.org)
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Dispersal of clonal aquatic plants
Rydlo, Jan ; Fér, Tomáš (advisor) ; Hroudová, Zdenka (referee)
The aim of this Bc. thesis is to summarize the knowledge on clonal dispersal of aquatic plants and to compare the possibilities and measure of clonal dispersal in selected most-studied species. In the first part of the study, ways of clonal propagation of water plants by various types of vegetative diaspores and various means of transport (by water, animals) are described. Ways and possibilities of dispersal of aquatic clonal plants in various water systems (river systems, stagnant waters) and to various distances are described as well. Finally, anthropogenic effects on clonal dispersal of water plants, which can also play an important role, are discussed. These effects could stay behind many invasive events on the Earth represented by rapid clonal reproduction and dispersal of some species of aquatic macrophytes in their non-native area. The next part of this thesis deals with methods to study the dispersal of aquatic clonal plants and assesses their relevance for various spatial scales. These methods and results of case studies are presented for the most often studied species of water macrophytes. Results of these studies are summarised to demonstrate the real efficiency and distances of clonal dispersal of aquatic plants. Powered by TCPDF (www.tcpdf.org)
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A taxonomic revision of the genus Callitriche in the Czech Republic
Prančl, Jan ; Kaplan, Zdeněk (advisor) ; Hroudová, Zdenka (referee)
Callitriche (water-starwort) belongs among difficult and insufficiently known genera of the Czech flora. The presented work provides the first critical taxonomic revision of the genus in the Czech Republic, with information relevant also to the broader region of Central Europe. Morphological and cytometric investigation resulted in identification of six Callitriche species in the Czech Republic. The genome size of all six Czech representatives of the genus was estimated using flow cytometry. The hybrid C. × vigens Martinsson (C. cophocarpa × C. platycarpa) was found for the first time in the Czech Republic. An individual related to C. hamulata was found in the Tichá Orlice river, which has aberrant genome size and aborted flowers; further study of this taxon is necessary. Multivariate morphometric analyses of fruits and cultivation were used to check and define reliable distinctive features and an impact of phenotypic plasticity. Key to the identification of species (including the first key for sterile plants), its detailed descriptions and ecological demands were provided. Each species differ significantly from the others in genome size, morphological features as well as in ecology. The reproductive strategy has the main importance for ecology and morphology of the studied species. The distribution of...
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