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Interaction of plants and soil and other factors affecting plant invasiveness
Aldorfová, Anna ; Münzbergová, Zuzana (advisor) ; Allan, Eric (referee) ; Šmilauer, Petr (referee)
Plant invasions represent a major ecological and socio-economical issue and understanding the drivers as well as consequences of plant invasions is thus one of the main goals of plant ecology. It is equally important to reveal general patterns underlying plant invasions and to understand the details of biology of individual invaders. In this thesis I explored plant-soil feedback (PSF) as a possible general mechanism underlying plant invasiveness, and also focused in detail on drivers and consequences of Impatiens parviflora invasion. The aims of this thesis were to i) assess the differences in intraspecific PSF between invasive and alien non-invasive species using a large set of species; ii) explore the relationship between PSF, residence time and phylogenetic novelty of the alien species; iii) compare the importance of PSF and other plant characteristics for plant invasiveness; iv) compare PSF between invasive and native congeners of similar level of dominance in the field; v) evaluate the effect of cultivating conditions on results of PSF experiments; vi) describe invasion dynamics and determine factors affecting spread of invasive I. parviflora using a method of monitoring its natural spread in several types of habitats, and vii) assess the impact of I. parviflora on native vegetation of oak-...
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Plant body as a behavioural platform - an ecologist's insight
Weiser, Martin ; Herben, Tomáš (advisor) ; Šmilauer, Petr (referee) ; Novoplansky, Ariel (referee)
Conceptualisation of plant behaviour, or plant phenotypic plasticity, has been proven to be useful both on the ecosystem scale and on the level of individuals, as it allows to predict differentiation of species across ecosystems or results of interactions among individuals. Between these extremes is a vast array of processes that drive community assembly. These processes are difficult to predict, be it at the individual level or based on whether a whole species is plastic or non-plastic. These processes are traditionally investigated at the species level. In this thesis, however, I instead show how species-specific life histories delineate plant behaviour. I hope to convince the reader that it is the plant body, or at least its species-specific properties, not merely its non-specific, theoretical degree of plasticity, that should be used to explain actual cases where plant behaviour underpins species coexistence. As evidence for my case, I present four studies, each of them dealing with different part of the plant body that underlies different aspects of plant behaviour. In the first study, I show how species' life- history traits are coordinated with their responses to neighbour presence and resource shortage, both of these delivered in the form of changing light quantity and quality. Not only the...
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Root system development in the early phases of plant ontogeny
Mašková, Tereza ; Weiser, Martin (advisor) ; Šmilauer, Petr (referee)
Root system development in the early phases of plant ontogeny Seed germination and subsequential developement of the root system is a critical stage of life of a newly rising plant. The plant must recognise and suitably and quickly find an answer to the environmental conditions in which it finds itself. However, the way in which the root system develops and its final architecture depends not only on the environmental conditions but also on the plant itself. In addition, responses to different conditions may vary among different plant species. This work examines the developement of a root system in the first four weeks of a plant's life. It observes the dependence on the amount of available nutrients in the substrate and on the amount of available nutrients the seed is given by the mother plant. It also briefly touches on the relations between seed germination, seed size and the amount of available nutrients. No differences relating to the amount of available nutrients were found in seed germination. However, differences in germination speeds were found between plant species. Plant biomass increases with the increasing amount of available nutrients in the substrate. This increase is relatively greater for plant species with a small seed size. Plant species with a big seed size invest relatively more...
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Interaction of plants and soil and other factors affecting plant invasiveness
Aldorfová, Anna ; Münzbergová, Zuzana (advisor) ; Allan, Eric (referee) ; Šmilauer, Petr (referee)
Plant invasions represent a major ecological and socio-economical issue and understanding the drivers as well as consequences of plant invasions is thus one of the main goals of plant ecology. It is equally important to reveal general patterns underlying plant invasions and to understand the details of biology of individual invaders. In this thesis I explored plant-soil feedback (PSF) as a possible general mechanism underlying plant invasiveness, and also focused in detail on drivers and consequences of Impatiens parviflora invasion. The aims of this thesis were to i) assess the differences in intraspecific PSF between invasive and alien non-invasive species using a large set of species; ii) explore the relationship between PSF, residence time and phylogenetic novelty of the alien species; iii) compare the importance of PSF and other plant characteristics for plant invasiveness; iv) compare PSF between invasive and native congeners of similar level of dominance in the field; v) evaluate the effect of cultivating conditions on results of PSF experiments; vi) describe invasion dynamics and determine factors affecting spread of invasive I. parviflora using a method of monitoring its natural spread in several types of habitats, and vii) assess the impact of I. parviflora on native vegetation of oak-...
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Plant body as a behavioural platform - an ecologist's insight
Weiser, Martin ; Herben, Tomáš (advisor) ; Šmilauer, Petr (referee) ; Novoplansky, Ariel (referee)
Conceptualisation of plant behaviour, or plant phenotypic plasticity, has been proven to be useful both on the ecosystem scale and on the level of individuals, as it allows to predict differentiation of species across ecosystems or results of interactions among individuals. Between these extremes is a vast array of processes that drive community assembly. These processes are difficult to predict, be it at the individual level or based on whether a whole species is plastic or non-plastic. These processes are traditionally investigated at the species level. In this thesis, however, I instead show how species-specific life histories delineate plant behaviour. I hope to convince the reader that it is the plant body, or at least its species-specific properties, not merely its non-specific, theoretical degree of plasticity, that should be used to explain actual cases where plant behaviour underpins species coexistence. As evidence for my case, I present four studies, each of them dealing with different part of the plant body that underlies different aspects of plant behaviour. In the first study, I show how species' life- history traits are coordinated with their responses to neighbour presence and resource shortage, both of these delivered in the form of changing light quantity and quality. Not only the...
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Plant strategies in belowground competition - insight through game theory
Smyčka, Jan ; Weiser, Martin (advisor) ; Šmilauer, Petr (referee)
In recent decades, it was shown that belowground competition for some plants may take form of the tragedy of the commons (TOC). In these plants, the competing neighbours invest more in root systems than would be appropriate for optimal nutrient uptake for the group and also more than they do when grown alone. However, there is also strong evidence that other species do not follow TOC, and tailor their root system to best nutrient exploitation irrespectively of competitor presence. The root investment strategy of these plants should correspond to the ideal free distribution (IFD). In my thesis I focus on two aspects: I use game theoretical models to explore, whether those strategies can coexist within species and also whether different species can coexist if they have different strategy. From this model I draw predictions, which I test by meta-analysis. Using Agrostis stolonifera as a model, I test assumptions on nutrient and neighbour perception, which underlie TOC and IFD models. I show that according to mathematical models, those two strategies can coexist in different species in a community, but cannot coexist within a species. Within a species, the TOC strategy should always dominate, once it appears. This can be extrapolated to macroevolutionary scale - once TOC occurs in certain clade, it should...
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Root system development in the early phases of plant ontogeny
Mašková, Tereza ; Weiser, Martin (advisor) ; Šmilauer, Petr (referee)
Root system development in the early phases of plant ontogeny Seed germination and subsequential developement of the root system is a critical stage of life of a newly rising plant. The plant must recognise and suitably and quickly find an answer to the environmental conditions in which it finds itself. However, the way in which the root system develops and its final architecture depends not only on the environmental conditions but also on the plant itself. In addition, responses to different conditions may vary among different plant species. This work examines the developement of a root system in the first four weeks of a plant's life. It observes the dependence on the amount of available nutrients in the substrate and on the amount of available nutrients the seed is given by the mother plant. It also briefly touches on the relations between seed germination, seed size and the amount of available nutrients. No differences relating to the amount of available nutrients were found in seed germination. However, differences in germination speeds were found between plant species. Plant biomass increases with the increasing amount of available nutrients in the substrate. This increase is relatively greater for plant species with a small seed size. Plant species with a big seed size invest relatively more...
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Populační biologie rostlin napadených systémovými parazity
Koubek, Tomáš ; Herben, Tomáš (advisor) ; Šmilauer, Petr (referee) ; Wennström, Anders (referee)
Three separate studies of the effect of plant pathogen on population biology of its host are presented in the thesis. Two are using field data about a widespread system of plant Falcaria vulgaris and its systemic rust fungus Puccinia sii-falcariae. The first study shows, that the disease prevalences in 40 populations of the plant were correlated with the moisture, the soil reaction and the cover of the herb layer at the localities. This was probably a result of the interaction of the life history of the plant and different effect the disease has at various localities. Similar pattern was found in the second study that aimed to determine long-term effect of the disease at the population level at four chosen localities over 4-5 years. Population growth rates were only rarely predicted to be higher for the healthy part of the population when compared with the whole population. Other analyses have however found big differences among years and localities. The locality type (slope vs. field populations) was important factor influencing population stage composition and importance of life cycle transitions for the growth of the population. Finally, the last study explores the possibility that systemic infection in clonal plants might be able to select against clonality. The result of the modelling showed that more...
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