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Seasonal and long-term dynamic of plankton communities of small water-bodies
Pejsar, Patrik ; Černý, Martin (advisor) ; Juračka, Petr Jan (referee)
Zooplankton pool-inhabiting organisms form metacommunities and metapopulations. Locations are connected through dispersion which is an essential part of colonization-extinction dynamic. Locations vary with the environmental conditions, the specifics of the community and the biotic interactions taking place there. Differences in these parameters may occur between spatially separated pools or in one pool throughout time. These changes are caused by seasonal dynamics, disturbances, long-term development of environmental conditions or biotic factors such as predation, competition and parasite influence. On a long-term scale the locations are classified into rather stable and ephemeral. In pool environment the ephemeral locations may unexpectedly be the driving force of metacommunity and metapopulation processes according to the "inverse mainland-island" theory. Global climate change has an essential influence on zooplankton dynamic in smaller water-bodies. Hydrology of pools and through it also life dynamics of plankton organisms is directly influenced by temperature changes and precipitation. Regional metacommunity and metapopulation dynamics are changing in dependency on regional course of climate change and the specifics of these water-bodies and the communities living there.
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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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Seasonal and long-term dynamic of plankton communities of small water-bodies
Pejsar, Patrik ; Černý, Martin (advisor) ; Juračka, Petr Jan (referee)
Zooplankton pool-inhabiting organisms form metacommunities and metapopulations. Locations are connected through dispersion which is an essential part of colonization-extinction dynamic. Locations vary with the environmental conditions, the specifics of the community and the biotic interactions taking place there. Differences in these parameters may occur between spatially separated pools or in one pool throughout time. These changes are caused by seasonal dynamics, disturbances, long-term development of environmental conditions or biotic factors such as predation, competition and parasite influence. On a long-term scale the locations are classified into rather stable and ephemeral. In pool environment the ephemeral locations may unexpectedly be the driving force of metacommunity and metapopulation processes according to the "inverse mainland-island" theory. Global climate change has an essential influence on zooplankton dynamic in smaller water-bodies. Hydrology of pools and through it also life dynamics of plankton organisms is directly influenced by temperature changes and precipitation. Regional metacommunity and metapopulation dynamics are changing in dependency on regional course of climate change and the specifics of these water-bodies and the communities living there.
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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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Spatial distribution and mobility of critically endangered Rock Grayling in the area of Orlik Reservoir
Váňová, Anežka ; Kadlec, Tomáš (advisor) ; Petr, Petr (referee)
The critically endangered grayling (Hipparchia hermione, syn.: alcyone) is one of the rapidly declining diurnal butterfly species which occupies only few remaining localities in the Czech Republic. Currently, its remaining local populations can be found in the central Povltavi area where they inhabit mostly sparse light oak forests with low cover of the herb layer. As a diploma thesis, the study was conducted during the season 2015. The populations of H. alcyone were researched around the Orlik water reservoir. The occurrence was confirmed at six localities out of which two had been unknown until then. Within four dense populations have been using the capture-recapture method evaluated the mobility and dispersal abilities of the species. The populations differed in their dispersal abilities. Various average long distances across localities and sexes were detected. The average long distances varied (males 142to300 m, females 78to261 m) across all locations. The flight probability were ascertained with two methods: the inverse power function (IPF) and the negative exponential function (NEF). The NEF method fitted better the flight probability at all localities. The interchanges of individuals between localities were noted only in a case of two closest populations. These one-way interchanges (three males and two females) were always directed from dense to smaller population. The adults of H. alcyone were typical by very low dispersions between separate populations, probably due to lower densities of populations and innapropriate structure of migration paths. Three overflights of males and two overflights of females to the neighbouring location were recorded. With respect to the size of local population and the structure of migration routes, the individuals expand with difficulties. In order to maintain and support habitats of new H. alcyone biotopes, the more open canopies and creation of a larger number of small clearings in the neighbourhood of the H. alcyone localities is necessary.
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