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Impact of river system structure on the genetic diversity of reed populations
Fuxová, Gabriela ; Fér, Tomáš (advisor) ; Kubátová, Barbora (referee)
Many plant species are closely related to river biotopes or to biotopes influenced by rivers. River systems create important linear corridors in ecosystems and directly or non-directly influence spatial spread of species in these environments. This offer many questions about species spread in this system. We can answer these questions by using molecular methods. Using 10 microsatellite (SSRs) primers, 202 individuals of Phragmites australis from 60 populations were analysed. Those analyses allowed reveal kinship of individuals, obtain information about spatial spread of populations and about spreading of common reed. Phragmites australis creates both - monoclonal and polyclonal - populations. Dependence of rate of clonality on environment was revealed. Populations from river banks are more monoclonal, populations from pond shores are more polyclonal. Populations are isolated. The highest percentage of variability was explained on among-population level. This is common for anemochoric species. Communication between populations is present, more on shorter distances. Evidence for vegetative spread was found on short distance. Generative spread is much more common. Long-distance spreading is mediated by generative diaspores - seeds. This spreading includes within-river spread, among-river spread and spreading...
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Long distance dispersal of Rumex alpinus
Řičařová, Veronika ; Münzbergová, Zuzana (advisor) ; Hadincová, Věroslava (referee)
Long-distance dispersal of Rumex alpinus was studied in the Giant Mountain in the National Park. The invasion of R. alpinus is there kind of problem. The work builds on a thesis from year 2007 (20007 Červenková), in which was made the model of the invasion of R. alpinus in the area of the Giant Mountain. The measurements of the seeds spread take place at four localities, three of them were for measuring of water dispersal and one was for measuring of winter dispersal. Anemochory was measured using traps in the meadow up to a distance of 50 m. The seeds were dispersed by wind to a distance of 20 meters. Hydrochory was measured using a network's traps in the streams up to 100 m. The largest measured water dispersal was 100 m. Hydrochory therefore proved to be an important factor, which influenced the invasion of R. alpinus. The storms and flood had the great influence on the hydrochory and anemochory. The prediction exponential curves were compiled from the data about the wind dispersal. The curves express the spread to more than a measured distance. The field dispersion curves were compared with theoretical curves, which were used in the model of the invasion from 2007. It turned out that the theoretical curves overestimate the spread of R. alpinus by wind. The dispersion of seeds was underestimated in the...
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Comparison of three trials used for assassement of ability to disperse by wind and its importance for colonazition of abandoned fields in Asteraceae species
Vlasta, Tomáš ; Knappová, Jana (advisor) ; Kotilínek, Milan (referee)
Several methods are used for studying seed dispersal (seed traps, tracking individual seeds, tracking seeds coloured by fluorescent colours, etc.) However, only a few studies compared results obtained by several methods. In first part of this master thesis, I compared the three above mentioned methods used for studying seed dispersal using species from Asteraceae family. From previous research within the study area (Úštěcko), it is known that dry grassland species are able to colonize abandoned fields. Using seed dispersal data obtained within this theses, I tried to assess the role of seed dispersal on distribution of dry grassland species on abandoned fields both on local and regional scale. The results showed that dispersal curves obtained by the three methods differ significantly. This results may be due to different wind conditions during the experiments. Seed trap data show results from long-term seed dispersal influenced by highly variable wind conditions. In contrary, seed release experiments showed results based on single dispersal event under limited wind conditions. Tracking seeds coloured by fluorescent colours was shown to be not convenient for small seeds, but I can recommend this method for larger seeds. Influence of seed dispersal ability on abundance of dry grassland species on...
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Methods for studying seed dispersal and its importance for colonization of new sites
Vlasta, Tomáš ; Knappová, Jana (advisor) ; Hemrová, Lucie (referee)
Study of seed dispersal is crucial for understanding of several processes in life of plants and landscape. Seed dispesal is very important for persistence of local populations in fragmented landscape, it plays an important role in succession, it helps to protect plant populations againts loss of genetic variability. We usually recognize several types of seed dispersal depending on vector (dispersal by wind, animals and water.) In nature, it is very common that seed can be independently dispersed by several vectors. Therefore, studying of polychory and secondary dispersal is necessery. Methods of studying of seed dispersal are very variable, including seed traps, releasing and following individual seeds, genetics marcers etc. If we study seed dispersal, we should select the most suitable method depending on the aim of the study. We should also take into acount advantages and disadvantages of single method.
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Impact of river system structure on the genetic diversity of reed populations
Fuxová, Gabriela ; Fér, Tomáš (advisor) ; Kubátová, Barbora (referee)
Many plant species are closely related to river biotopes or to biotopes influenced by rivers. River systems create important linear corridors in ecosystems and directly or non-directly influence spatial spread of species in these environments. This offer many questions about species spread in this system. We can answer these questions by using molecular methods. Using 10 microsatellite (SSRs) primers, 202 individuals of Phragmites australis from 60 populations were analysed. Those analyses allowed reveal kinship of individuals, obtain information about spatial spread of populations and about spreading of common reed. Phragmites australis creates both - monoclonal and polyclonal - populations. Dependence of rate of clonality on environment was revealed. Populations from river banks are more monoclonal, populations from pond shores are more polyclonal. Populations are isolated. The highest percentage of variability was explained on among-population level. This is common for anemochoric species. Communication between populations is present, more on shorter distances. Evidence for vegetative spread was found on short distance. Generative spread is much more common. Long-distance spreading is mediated by generative diaspores - seeds. This spreading includes within-river spread, among-river spread and spreading...
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Long distance dispersal of Rumex alpinus
Řičařová, Veronika ; Münzbergová, Zuzana (advisor) ; Hadincová, Věroslava (referee)
Long-distance dispersal of Rumex alpinus was studied in the Giant Mountain in the National Park. The invasion of R. alpinus is there kind of problem. The work builds on a thesis from year 2007 (20007 Červenková), in which was made the model of the invasion of R. alpinus in the area of the Giant Mountain. The measurements of the seeds spread take place at four localities, three of them were for measuring of water dispersal and one was for measuring of winter dispersal. Anemochory was measured using traps in the meadow up to a distance of 50 m. The seeds were dispersed by wind to a distance of 20 meters. Hydrochory was measured using a network's traps in the streams up to 100 m. The largest measured water dispersal was 100 m. Hydrochory therefore proved to be an important factor, which influenced the invasion of R. alpinus. The storms and flood had the great influence on the hydrochory and anemochory. The prediction exponential curves were compiled from the data about the wind dispersal. The curves express the spread to more than a measured distance. The field dispersion curves were compared with theoretical curves, which were used in the model of the invasion from 2007. It turned out that the theoretical curves overestimate the spread of R. alpinus by wind. The dispersion of seeds was underestimated in the...
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Reconstruction and model of postglacial spread of subgenus Alnus in Europe
Jelenová, Hana ; Barták, Vojtěch (advisor) ; Mandák, Bohumil (referee)
Many paradoxes exist about postglacial tree migration and they dont solve for many European trees. One example is wetland trees subgenus Alnus, which spread across Europe during the last glacial very quickly according to fossil records. The aim of this thesis is detection their migration potential, with the help of empirical evaluation of interpolated pollen data (interpolation method IDW) and a simulation model based on environmental characteristics of the species. The results of interpolated maps are similar to the rate previously estimated speed and the results of simulation model achieve these speeds only by A. incana but with specific extreme environmental conditions. The mason of this may be adapting its seeds to anemochorii because the simulation model confirmed their good potential to spread by the wind. Results of model for A. glutinosa don´t confirm the ability to rapidly spread by the wind and the observed rate must have another explanation. Maybe rivers can explain the empirical spread rate. This suggests visualization of migration lines and river networks.
The model has also been disclosure of environmental properties that are related to migration potential. Within the parameterization of the model is demonstrated, that R0 of A. glutinosa is significantly better than A. incana. But main parameters of anemochory model are terminal velocity and generation time, which is shorter by the A. incana, and therefore is probably able to spread faster than A. glutinosa.
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