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Vegetation succession on fallows in Podyjí National Park - small-area management of abandoned sites
Entová, Martina ; Fabšičová, Martina (advisor) ; Karlík, Petr (referee)
The main aim of the thesis was to describe the succession of several abandoned fields under ploughing and discuss ploughing as a possible management for establishing and maintaining species-rich communities of fallows. Actual vegetation, its development over time and soil seed bank were studied. Experimental small-area ploughing was established at five abandoned fields in the southeastern part of the Podyjí National Park. Three strips with different types of management were founded: A) strip ploughed each year, B) strip ploughed once at the beginning of the experiment, C) control meadow without intervention. Vegetation development was evaluated through a series of relèves recorded during the years 2009-2012. The species composition of the seed bank was described using the seedling-emergence method and subsequent elutriation of soil samples. Similarity indexes, Longevity index (LI) and concept of RCS strategies were used. The vegetation of each-year plowed sites (A) consisted mostly of annual weeds and ruderal species with R-strategy and high LI. Grassland vegetation (C) consisted mostly of grasses and perennial herbs with C-strategy and lower LI. The vegetation of older fallows (B) was at first most similar to one-year fallow (A), but during the 4 years of succession has moved closer to the meadow...
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Landscape structure, habitat properties, species traits or chance: What determines distribution of grassland plants in abandoned fields?
Knappová, Jana ; Münzbergová, Zuzana (advisor) ; Hájek, Michal (referee) ; De Bello, Francesco (referee)
Semi-natural grasslands are among the most threatened habitats in Europe, endangered mainly by cessation of former management practices and conversion into other types of land use. Extensive research has been carried out in European grasslands in last decades, to explain origins of diversity and to provide guidelines for its conservation. However, the very slow response of perennial plants to landscape changes often impedes to accurately evaluate why species occur just where they occur and not elsewhere. Abandoned fields are perceived as potential habitats for species from declining grasslands. Indeed, many species are able to spontaneously colonise abandoned fields, but many other species are absent from communities that develop there. An important question remains what limits their successful establishment. By answering this question, we can gain also important insights into factors determining species distribution in grasslands because colonization of recently abandoned fields by grassland species is the ongoing process which is not obscured by historical changes in landscape structure. The very basic aim of this thesis was to evaluate the status quo of dry grassland plants in fields abandoned in last two decades. And in the second step, to identify what are the main constrains of successful...
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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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Vegetation succession on fallows in Podyjí National Park - small-area management of abandoned sites
Entová, Martina ; Fabšičová, Martina (advisor) ; Karlík, Petr (referee)
The main aim of the thesis was to describe the succession of several abandoned fields under ploughing and discuss ploughing as a possible management for establishing and maintaining species-rich communities of fallows. Actual vegetation, its development over time and soil seed bank were studied. Experimental small-area ploughing was established at five abandoned fields in the southeastern part of the Podyjí National Park. Three strips with different types of management were founded: A) strip ploughed each year, B) strip ploughed once at the beginning of the experiment, C) control meadow without intervention. Vegetation development was evaluated through a series of relèves recorded during the years 2009-2012. The species composition of the seed bank was described using the seedling-emergence method and subsequent elutriation of soil samples. Similarity indexes, Longevity index (LI) and concept of RCS strategies were used. The vegetation of each-year plowed sites (A) consisted mostly of annual weeds and ruderal species with R-strategy and high LI. Grassland vegetation (C) consisted mostly of grasses and perennial herbs with C-strategy and lower LI. The vegetation of older fallows (B) was at first most similar to one-year fallow (A), but during the 4 years of succession has moved closer to the meadow...
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Landscape structure, habitat properties, species traits or chance: What determines distribution of grassland plants in abandoned fields?
Knappová, Jana ; Münzbergová, Zuzana (advisor) ; Hájek, Michal (referee) ; De Bello, Francesco (referee)
Semi-natural grasslands are among the most threatened habitats in Europe, endangered mainly by cessation of former management practices and conversion into other types of land use. Extensive research has been carried out in European grasslands in last decades, to explain origins of diversity and to provide guidelines for its conservation. However, the very slow response of perennial plants to landscape changes often impedes to accurately evaluate why species occur just where they occur and not elsewhere. Abandoned fields are perceived as potential habitats for species from declining grasslands. Indeed, many species are able to spontaneously colonise abandoned fields, but many other species are absent from communities that develop there. An important question remains what limits their successful establishment. By answering this question, we can gain also important insights into factors determining species distribution in grasslands because colonization of recently abandoned fields by grassland species is the ongoing process which is not obscured by historical changes in landscape structure. The very basic aim of this thesis was to evaluate the status quo of dry grassland plants in fields abandoned in last two decades. And in the second step, to identify what are the main constrains of successful...
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Vegetation succession in old fields at broad landscape scales
JÍROVÁ, Alena
This thesis is focused on succession in old fields in Central Europe. Repeated sampling, analysis of surrounding vegetation and soil measurements were conducted in the Bohemian Karst Landscape protected area. Samples from the Doupovské hory Mountains and the rest of the Czech Republic were added to discover basic principles of old field succession at the larger scale of landscapes.
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