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Intraspecific plant-soil feedback as a mechanism underlying invasiveness of neophytes of the Czech Republic
Knobová, Pavlína ; Münzbergová, Zuzana (advisor) ; Štajerová, Kateřina (referee)
Intraspecific plant-soil feedback is a relationship in which plant affects the composition of the soil and such modified soil affects growth of the same plant species. This relationship and its intensity may be linked with plant dominance and invasiveness. Dominant species can alter the composition of the soil in their favor and thus show positive intraspecific plant-soil feedback. As the invasive species are commonly being dominant in their new environment, it can be expected that intraspecific positive plant-soil feedback could be an important factor allowing the invasive species to achieve their dominant position and become invasive. To test if the existence of positive intraspecific feedback could be a general mechanism underlying plant invasiveness I compared intraspecific plant-soil feedback in a group of invasive and introduced, but non-invasive, plants in the Czech Republic. I did this using a preselected set of 34 species - 17 invasive and 17 non-invasive. For realization of the project I used the method of two-phase experiment. The first phase is called soil conditioning - influencing of soil by the plant. In the second phase the same plant species are planted in conditioned soil from the first phase and in control (unconditioned) soil. Then I compared plant biomass from conditioned and...
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Alien species of plants and biotic resistence of invaded communities
Kubátová, Michaela ; Dostál, Petr (advisor) ; Frouz, Jan (referee)
Michaela Kubátová Alien species of plants and biotic resistence of invaded communities This study is about problems and questions of alien plants and their relation to native communities in their new range. Ecologists are increasingly aware that soil organisms may affect plant communities because they are part of the processes that affect them. The soil organisms may affect the success of alien species invasion. Each species of plants differ in interaction with soil organisms, these interactions can result in specific feedback that will influence the future growth of other plants. According to Darwin's naturalization hypothesis related species should have similar enemies. This implies less successful invasion of alien plants at home with relatives. The practical part consists of two experiments. Using plant-soil feedback I studied under controlled conditions the importance of kinship of native plants and their soil organisms on the growth of three species of alien plants Impatiens, Parviflora, Stenactis annua and Epilobium ciliatum. There were used soil samples from localities with related and unrelated species; the soil was used as inoculums for growing first-generation plants, where there were original related, unrelated and alien plants. In the second phase only alien species were grown. Part of...
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The effect of invasive and native plants on abiotic and biotic soil properties
Hanzelková, Věra ; Aldorfová, Anna (advisor) ; Sudová, Radka (referee)
Invasive plants represent an important topic of study in current ecology because of their effects on whole ecosystems. The plants interact with the soil including soil biota, with the other plants in the community and with other organisms, eg. herbivores. Invasive plants often differ from non- invasive plants in nutrient utilization and can thus affect soil pH as well. They may also differ in the way they interact with mycorrhizal fungi that help the plants with nutrient uptake. In this study, the effect of invasive and native plants on soil properties is compared. Congeneric pairs of species, where one species is native and the other invasive, are compared. The native species are chosen so that they are dominant and therefore comparable to the invasive plants in the new environment. The evaluated soil properties are pH value and content of elemental nutrients from abiotic properties, and the amount of mycorrhizal fungi propagules and their spreading rate in soil from the biotic properties. In this study, the invasive and native plants differ only in the content of exchangeable phosphorus and potassium. Content of these two nutrients and one of the indicators of mycorrhizal fungi differ within the pairs of species as well. For most soil properties, the genus of the plant plays the main role, not...
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Phenotypic plasticity and its role in plant invasions
Hlavička, Matěj ; Herben, Tomáš (advisor) ; Skálová, Hana (referee)
Phenotypic plasticity is the ability of given genotype to produce different phenotypes as a response to environmental cues. Its capability of adaptive response draws an attention of invasion biologists. Although many studies have been performed, the true role of plasticity in an invasion process is still unclear. Comparative experiments suffer from several major constraints - insufficiency in revealing adaptive value of plastic response and uncertain linkage between plasticity and trait value. Further experiments could be focused to reaction norms of fitness instead of trait plasticity. Also, the interspecific interaction of plastic responses is definitely an underestimated mechanism and deserves far more attention than it does today. Possible implications of plant phenotypic plasticity in predicting future invasions require further reaserch.
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Vegetation regeneration after removal of invasive plants
Pojslová, Lucie ; Münzbergová, Zuzana (advisor) ; Rumlerová, Zuzana (referee)
Invasive plants change local diversity and abundance of native plant species in the invaded area. However, changes are not visible only in vegetation, but also on single levels of abiotic and biotic characteristics of the invaded area. The aim of the thesis is not only to summarize current knowledge about the impact of invasive plants on vegetation, but also point out possible recovery of the vegetation and the direction of its succession after the removal of invasive plants. I present factors which limit the recovery of vegetation and types of management used for control of invasive species. I also describe biology, ecology and invasive history of fringed willowherb (Epilobium ciliatum spp. adenocaulon) which I want to use as a model plant for my future thesis. Finally, I mention experimental methods that are used for studying regeneration of invaded areas and the possibility of using invasive plants for regeneration of degraded soils.
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Floodplain mollusc fauna of the lower Elbe and its tributaries -its history, ecology and changes induced by invasion plant species
Horáčková, Jitka
The molluscs are very suitable model of invertebrate group for ecological and palaeoecological studies for their specific traits. In the first part of the thesis, we showed based on available fossil mollusc successions that development of the floodplain mollusc fauna took place quite different way in various river floodplains, depending on their specifics and geographical location, because especially the ones situated in the chernozem area of the Czech Republic had very different history. Detailed processing of five fossil mollusc successions in the lower Ohře River floodplain confirmed the impoverishment of recent forest malacofauna does not relate to natural processes only (chapters 3 and 10), but it arises from historical development of this area which was under permanent stress of the human settlement and agricultural utilization (chapter 1) since the coming of the Neolithic people. We made similar conclusions in case of another 11 fossil mollusc successions in the neighbouring České Středohoří Mts. (chapter 2). In the second part of the thesis (chapter 3), we investigated the ecological patterns responsible for species richness and composition of the floodplain mollusc fauna are especially the elevation and humidity gradient, and then vegetation type and its biomass, light conditions of the...
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Biotic and abiotic components of soil in plant-soil feedback of invasive and native plant species
Drtinová, Lucie ; Münzbergová, Zuzana (advisor) ; Štajerová, Kateřina (referee)
Plant-soil feedback (PSF) is a mechanism which may contribute to the success of invasive plant species. Which of the soil components have the greatest impact on PSF? In a two-phase experiment, I observed changes in germination and growth of plants in reaction to intraspecific plant cultivation: selected plant species were grown in substrate consisting of cultivated or uncultivated soil, containing different composition and amounts of soil biota. The effect of changes in abiotic and biotic components of the soil was then assessed and compared among pairs of closely related invasive and native plant species. The main observed phenomenon was species-specificity of plant responses to changed soil conditions. The cultivation-induced changes in soil composition affected germination and biomass of the test plants positively, negatively, or were neutral, their effect differed between tested species - some of the observed species were more affected by changes in abiotic properties of the soil, some reacted to changes in soil biota composition. Nevertheless, the composition of soil biota affected germination and biomass of plants even regardless of cultivation: the presence of all biotic components of the soil had negative effect on biomass - with growing representation and amount of pathogens, fungi, micro-...
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The effect of invasive and native plants on abiotic and biotic soil properties
Hanzelková, Věra ; Aldorfová, Anna (advisor) ; Sudová, Radka (referee)
Invasive plants represent an important topic of study in current ecology because of their effects on whole ecosystems. The plants interact with the soil including soil biota, with the other plants in the community and with other organisms, eg. herbivores. Invasive plants often differ from non- invasive plants in nutrient utilization and can thus affect soil pH as well. They may also differ in the way they interact with mycorrhizal fungi that help the plants with nutrient uptake. In this study, the effect of invasive and native plants on soil properties is compared. Congeneric pairs of species, where one species is native and the other invasive, are compared. The native species are chosen so that they are dominant and therefore comparable to the invasive plants in the new environment. The evaluated soil properties are pH value and content of elemental nutrients from abiotic properties, and the amount of mycorrhizal fungi propagules and their spreading rate in soil from the biotic properties. In this study, the invasive and native plants differ only in the content of exchangeable phosphorus and potassium. Content of these two nutrients and one of the indicators of mycorrhizal fungi differ within the pairs of species as well. For most soil properties, the genus of the plant plays the main role, not...
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The impact of invasive plants on bird communities
Neubergová, Kristýna ; Reif, Jiří (advisor) ; Hanzelka, Jan (referee)
Invasive plants are among the major factors participating on the threat to biodiverzity. Birds are one of the Gross of organism endangered by this factor. However, birds provide a variety of ecological services and are often used as indicators of the state of enviroment in broker scale of landscape. Several researches assessing impal of invasive plants on ecosystem biodiverzity have been done, but none of them targeted bird communities specifically. Objective of this paper will be to anter free question regarding: (i) comparison of impacts of invasive woody plants and plants; (ii) comparison of impacts by type of enviroment in which the inavasive plant expanded (forest, grasses, island, wetlands); (iii) geographical area sof invasion. (i) The results indicie that from the perspective of bird communities, the negative impact of woody plants and plants was basically identical (76% for woody plants, 74% for plants). (ii) Comparison of impacts by type of enviroment in which the invasive plant expanded proved that the most severe negative impal of invasive plants was in islands biomes (100%), wetlands (91%), grassy biomes (87%). The lest severe impal was in forest biomes (63%). The results for island biomes was quite expected, as this biome is the most susceptible to disbalance of ecosystem. (iii)...
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Intraspecific plant-soil feedback as a mechanism underlying invasiveness of neophytes of the Czech Republic
Knobová, Pavlína ; Münzbergová, Zuzana (advisor) ; Štajerová, Kateřina (referee)
Intraspecific plant-soil feedback is a relationship in which plant affects the composition of the soil and such modified soil affects growth of the same plant species. This relationship and its intensity may be linked with plant dominance and invasiveness. Dominant species can alter the composition of the soil in their favor and thus show positive intraspecific plant-soil feedback. As the invasive species are commonly being dominant in their new environment, it can be expected that intraspecific positive plant-soil feedback could be an important factor allowing the invasive species to achieve their dominant position and become invasive. To test if the existence of positive intraspecific feedback could be a general mechanism underlying plant invasiveness I compared intraspecific plant-soil feedback in a group of invasive and introduced, but non-invasive, plants in the Czech Republic. I did this using a preselected set of 34 species - 17 invasive and 17 non-invasive. For realization of the project I used the method of two-phase experiment. The first phase is called soil conditioning - influencing of soil by the plant. In the second phase the same plant species are planted in conditioned soil from the first phase and in control (unconditioned) soil. Then I compared plant biomass from conditioned and...
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