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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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Passive dispersal of land snails (Gastropoda: Pulmonata) with focus on endodispersion via birds
Simonová, Jasna ; Juřičková, Lucie (advisor) ; Pech, Pavel (referee)
The ability of land snail active dispersal is very limited. Despite that, they have colonized even very isolated habitats and some species are able to disperse relatively fast on continental scale. This used to be explained by passive dispersal, especially via birds. Land snails could be transported on bird's body (ectodispersion) as well as inside their digestive tract (endodispersion), but the direct evidence of these processes has been more likely anecdotal. A review concerning passive dispersal of land snails via birds with focus on endodispersion is presented in this bachelor thesis. The methodological aspects of experimental studies, including relevant insights of other organism's endodispersion studies, are discussed. Selected traits of land snails and their avian vectors which can affect success of endodispersion are also discussed.
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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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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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