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Environmental factors determining the occurrence of dry grassland vegetation in Turnov region
Jagošová, Eliška ; Novák, Jan (advisor) ; Větvičková, Anna (referee)
Species diversity of vegetation is a result of not only present, but also past processes. Additionally vegetation is affected by local factors, as well as regional. Dry grasslands are significant due to their abundance of species. Farming and land-use changes lead to succession changes and subsequently also to changes in species diversity. The gradual degradation of habitats leads to a loss of species diversity, therefore, dry grasslands are becoming one of the most endangered vegetation types of Central Europe. The first part of this thesis focuses on dry grasslands in general. It presents the characteristics of this vegetation type, factors determining its occurrence and spread, historical context, threats, and possibilities of their protection. The second part focuses on evaluating the knowledge about dry grasslands in the region of Turnovská pahorkatina. The occurrence of this vegetation type within the framework of this region is marginal and centred only in specific habitats. This thesis also includes data about the occurrence of dry grasslands in the region of Turnovská pahorkatina and the characteristic of the natural conditions and historical development of these localities. The purpose of this bachelor thesis is to find out which of the factors affect the occurrence of dry grasslands in a...
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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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Dynamics of species of fragmented dry grasslands at the landscape scale
Hemrová, Lucie ; Münzbergová, Zuzana (advisor) ; De Bello, Francesco (referee) ; Zelený, David (referee)
Past extensive changes in land use have resulted in fragmentation of species habitats. Changes in landscape structure have provoked discussion about the prospects of species of fragmented habitats in the future agricultural landscape. Landscape dynamics of plant species is basically a result of extinction and colonization rates. Many studies have confirmed the former expectation that a number of habitats suitable for a plant species in a landscape stay unoccupied. The differences in species distribution and proportion of suitable habitats occupied by a given species are hypothesized to be due to the area and isolation of suitable habitats and colonization and survival ability of a given species. To understand species dynamics in a changing landscape, first we have to reveal the relationships between the distribution of species and their proportion of occupied habitats, habitat age, habitat configuration and species colonization and survival ability. After the complete understanding of the determinants of species dynamics we will be able to predict reliably species prospect in the future. The very basic aim of this thesis was to reveal the determinants of landscape dynamics of dry grassland species in terms of their distribution and frequency in the landscape. The importance of correct identification...
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Dynamics of species of fragmented dry grasslands at the landscape scale
Hemrová, Lucie
Past extensive changes in land use have resulted in fragmentation of species habitats. Changes in landscape structure have provoked discussion about the prospects of species of fragmented habitats in the future agricultural landscape. Landscape dynamics of plant species is basically a result of extinction and colonization rates. Many studies have confirmed the former expectation that a number of habitats suitable for a plant species in a landscape stay unoccupied. The differences in species distribution and proportion of suitable habitats occupied by a given species are hypothesized to be due to the area and isolation of suitable habitats and colonization and survival ability of a given species. To understand species dynamics in a changing landscape, first we have to reveal the relationships between the distribution of species and their proportion of occupied habitats, habitat age, habitat configuration and species colonization and survival ability. After the complete understanding of the determinants of species dynamics we will be able to predict reliably species prospect in the future. The very basic aim of this thesis was to reveal the determinants of landscape dynamics of dry grassland species in terms of their distribution and frequency in the landscape. The importance of correct identification...
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Dynamics of species of fragmented dry grasslands at the landscape scale
Hemrová, Lucie
Past extensive changes in land use have resulted in fragmentation of species habitats. Changes in landscape structure have provoked discussion about the prospects of species of fragmented habitats in the future agricultural landscape. Landscape dynamics of plant species is basically a result of extinction and colonization rates. Many studies have confirmed the former expectation that a number of habitats suitable for a plant species in a landscape stay unoccupied. The differences in species distribution and proportion of suitable habitats occupied by a given species are hypothesized to be due to the area and isolation of suitable habitats and colonization and survival ability of a given species. To understand species dynamics in a changing landscape, first we have to reveal the relationships between the distribution of species and their proportion of occupied habitats, habitat age, habitat configuration and species colonization and survival ability. After the complete understanding of the determinants of species dynamics we will be able to predict reliably species prospect in the future. The very basic aim of this thesis was to reveal the determinants of landscape dynamics of dry grassland species in terms of their distribution and frequency in the landscape. The importance of correct identification...
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Dynamics of species of fragmented dry grasslands at the landscape scale
Hemrová, Lucie ; Münzbergová, Zuzana (advisor) ; De Bello, Francesco (referee) ; Zelený, David (referee)
Past extensive changes in land use have resulted in fragmentation of species habitats. Changes in landscape structure have provoked discussion about the prospects of species of fragmented habitats in the future agricultural landscape. Landscape dynamics of plant species is basically a result of extinction and colonization rates. Many studies have confirmed the former expectation that a number of habitats suitable for a plant species in a landscape stay unoccupied. The differences in species distribution and proportion of suitable habitats occupied by a given species are hypothesized to be due to the area and isolation of suitable habitats and colonization and survival ability of a given species. To understand species dynamics in a changing landscape, first we have to reveal the relationships between the distribution of species and their proportion of occupied habitats, habitat age, habitat configuration and species colonization and survival ability. After the complete understanding of the determinants of species dynamics we will be able to predict reliably species prospect in the future. The very basic aim of this thesis was to reveal the determinants of landscape dynamics of dry grassland species in terms of their distribution and frequency in the landscape. The importance of correct identification...
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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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Bryophytes of dry grasslands in southern part of PLA Český kras
TENČÍK, Aleš
The aim of the thesis was to survey the occurrence of mosses in the different types of calcareous dry grasslands in the southwestern part of the Bohemian Karst and assess the impact of major abiotic and biotic factors to their diversity.At seven habitat types was acquired a total of 35 plots of 1x1 m. The most important factor influencing the diversity of mosses turned out to be the degree of coverage of herb layer markedly influenced by used type of management.Dry grasslands with Festuca pallens (T3.1) and Sesleria grasslands (T3.2) appeared to be rich in moss species. Conversely mossy low diversity here is presented by broad-leaved dry grasslands (T3.4).
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