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The role of biotic interactions in plant invasions
Štajerová, Kateřina ; Pyšek, Petr (advisor) ; Prach, Karel (referee) ; Richardson, David M. (referee)
- ABSTRACT - The loss of co-adapted and gain of novel biotic interactions during the invasion process influence the success or failure of introduced plants. Within the present thesis, I studied diverse biotic interactions, specifically the relationships between plants and their herbivores, pollinators, fungi, and resident plant communities, and how biotic interactions can be utilized in planning effective science-based management. With my collaborators, we combined the community and biogeographical approach with the reciprocal transcontinental comparison between Eurasia and North America, based on primary data collected in the field. Of numerous hypotheses for the striking success of invasive plants, the enemy release hypothesis (ERH) is one of the most frequently tested. It asserts that the greater performance of introduced plants in non-native ranges is due to the absence, or decrease, in regulation by natural enemies that are left behind in the native range. Our results, in a broad sense, supported ERH, but we found that the magnitude of herbivore damage is context-dependent, related to the feeding guild and origin of both herbivores and plant species and that the increased plant performance in a new range might also be related to other factors, such as the shift in plant competition. Of animal-plant...
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Assessment of disused sand and gravel pits in the Třeboň region from the perspective of landscape ecology
Eliášová, Kateřina ; Matějček, Tomáš (advisor) ; Lipský, Zdeněk (referee)
This thesis summarizes findings gained about abandoned sand and gravel pits located in the Třeboňsko Protected Landscape Area. A study of written documents, old maps, aerial images and a field survey of selected sites were used to find out information on mining and mining pits. In the survey, erosion of mining walls, pollution, land use, land cover, dominant and invasive plant species and moisture of mining pits were monitored in sectors of approx. 1 ha or the bank length of about 500 m. A total of 127 sites was included, 37 of which were surveyed in the field. A classification has been created based on age, size, moisture conditions and current land use. Changes caused by mining, including changes in land use and land cover before and after mining, as well as the interaction of mining sites with the Territorial System of Ecological Stability (ÚSES) were also monitored. The majority of sand and gravel pits are small with an area less than 1 ha, dry pits predominate, and most sites were abandoned in the 1970s to 1990s. In about half of the cases, the land cover or land use from before mining have been restored. The main land cover change is the formation of large lakes and forests while the non-forest surface is more diversified after mining. Sites converted into arable land or built-up areas are...
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Habitat colonization by neophyte Impatiens glandulifera and estimate of factors limiting its spread
Marková, Zuzana ; Hejda, Martin (advisor) ; Malíková, Lenka (referee)
Invasive spread of neophyte Impatiens glandulifera in central Europe started approximatelly eighty years ago. First records of dense cover stands come from belt stands in riparian habitats. The scale of invaded habitats and degree of the dominance of I. glandulifera is more diversified nowadays. This thesis is objected on the dominance and fertility of I. glandulifera within different habitat types and scale of invaded habitats in different parts of invaded range within Europe (i. e. in Czech Republic and Switzerland). The results show that the height and cover (substitutes for biomass and dominance) of this neophyte (i) correlates with the character of invaded vegetation (ii) relates to the degree of hemeroby (a measure of human impact) negativelly, and (iii), of course, both the growth and dominance are positively affected by nutrient content. Fertility does not differ among the types of invaded habitats, but goes up with the height of I. glandulifera and decreases with its cover. Invaded habitats comprises ruderal and riparian vegetation, but also wet maedows, forest clearances, beach and slope forests or weed vegetation.
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Effect of plant-soil feedback on plant invasiveness
Knobová, Pavlína ; Münzbergová, Zuzana (advisor) ; Štajerová, Kateřina (referee)
Understanding the causes of biological invasions is a key topic of ecological research in the last decades. Invasive plant species threaten communities, ecosystems and humans in many different ways. Therefore, it is important to determine what characteristics enable them to become invasive. In this work, I summarize the possible causes and consequences of plant invasions focusing on one possible mechanism - the plant-soil feedback. This feedback can support or suppress the growth of plants. Most species have negative feedback, but some invasive plants have positive feedback. And that could be the cause of their invasiveness. This work summarizes the findings of the plant-soil feedback, the methods to study the feedback and especially the importance of plant-soil feedback for plant invasiveness.
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Habitat requirements and competition between native and invasive Impatiens species
Čuda, Jan ; Skálová, Hana (advisor) ; Prach, Karel (referee)
Three of Impatiens species are widespread in the Czech republic, one is native, two of them invasive. Because all species occur in relatively similar habitats, the question is, whether the invasive species can negatively affect the native species, or even the original can can be displaced. The aim of the thesis was: (i) to compare habitat requirments of the Impatiens species, (ii) to determine if the coexistence of species is possible, (iii) to assess the impact of invasive species to the original species. The investigation was carried out using two sets of permanent plots in 5 localities. In the first set with a total of 84 plots (combinations of occurrence of the three species) site characteristics as tree cover, soil humidity, slope and bare land cover were directly measured and nutrient, light, humidity and soil reaction characteristic assessed using Ellenberg indicator values. The second set contained a total of 45 plots with one of the native-invasive congener pair being removed and the intact controls. Number, cover and height of the plants were assesed. The key enviromental factors determining distribution of the species were soil moisture for I. noli-tangere and I. parviflora, and tree cover for I. glandulifera and I. parviflora. Ellenberg indicator values had poor explanation value;...
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Interactions between plants and soil biota and effect of energetic crops on these interactions
Heděnec, Petr ; Frouz, Jan (advisor) ; Pergl, Jan (referee) ; Mortimer, Simon (referee)
My PhD thesis is focused on study of plant-soil interactions. Chapter 1 is focused on general introduction to the interactions between plants and soil biota in terms of relationships between soil organisms and aboveground biomass as well as root biomass. Chapter 2 is focused on food interaction of Folsomia candida and soil microscopic fungi (Penicillium chrysogenum, Penicillium expansum, Absidia glauca, and Cladosporium herbarum). Fungi were grown separately on Petri dishes or on different litter type (oak, alder and willow) separately as well. Laboratory experiments showed that food preference was more influenced by different litter types than fungal species. In chapter 3 was studied long-term production of hybrid sorrel and its effect on the composition of the soil meso and macrofauna, basal soil respiration, microbial biomass and composition of cultivable fraction of soil microscopic fungi in comparison with oilseed rape and cultural meadow. There was found that long-term production of hybrid sorrel affects the composition of soil fauna, while the microbial activity of the soil was more affected by agriculture practices, especially tillage. In chapter 4 was studied the effect of native (Salix viminialis and Phalaris arudinacea) and introduced (Reynoutria sachalinensis, Silphium perfoliatum and...
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Sources and causes of spread of newly introduced plant species
Schmiedlová, Barbora ; Münzbergová, Zuzana (advisor) ; Čuda, Jan (referee)
The bachelor's thesis is written in the form of a literature review and deals with factors that affect the current global spread of plants into new areas, and their possible invasiveness in the new areas. The aim is to verify the hypothesis that one of the main causes of the spread of new plant species (the last 50 years aprox.) to new areas could be climate change. The introductory part of the thesis explains the basic concepts (native versus non-native species, invasive species, temporarily introduced species, etc.) and lists the main factors that affect the global distribution of non-native plant species. The following is a description of the issue of current global change, focusing primarily on climate change and what impact it may have on the spread of plant species. The last part of the work focuses on newly introduced non-native plant species and on the factors that influence their global distribution the most, in comparison with plant species introduced a long time ago (more than 50 years ago). It was found that climate change does have a significant impact on the shift of the area of distribution of newly introduced plant species, especially to extreme areas (higher altitude etc.). Several selected non-native plant species, in which a shift in the range of distribution due to climate...
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The spread of invasive neophytes in the riparian vegetation of the Kamenice river
Holzknechtová, Nikola ; Matějček, Tomáš (advisor) ; Bartoš, Jan (referee)
Watercourses and especially their riparian vegetation are habitats that are very sensitive to spreading of invasive plant species. Rivers create natural migration routes (corridors) and help propagules to spread quickly and easily. The theoretical part of this thesis is focused on plant invasions and covers also the most recent knowledge in the field of invasion ecology. In the practical part of this thesis the spread of invasive neophytes in the riparian vegetation of the Kamenice river in Northern Bohemia is described. The plant species were examined during the field survey along the entire stream of the Kamenice river. In total, common occurence of 7 invasive taxa were recorded, namely Impatiens parviflora, I. glandulifera, Reynoutria japonica, R. sachalinensis, R. bohemica, Solidago gigantea and S. canadensis. The distribution of observed taxa along the stream as well as on the banks was relatively uneven.
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Habitat colonization by neophyte Impatiens glandulifera and estimate of factors limiting its spread
Rumlerová, Zuzana
Invasive spread of neophyte Impatiens glandulifera in central Europe started approximatelly eighty years ago. First records of dense cover stands come from belt stands in riparian habitats. The scale of invaded habitats and degree of the dominance of I. glandulifera is more diversified nowadays. This thesis is objected on the dominance and fertility of I. glandulifera within different habitat types and scale of invaded habitats in different parts of invaded range within Europe (i. e. in Czech Republic and Switzerland). The results show that the height and cover (substitutes for biomass and dominance) of this neophyte (i) correlates with the character of invaded vegetation (ii) relates to the degree of hemeroby (a measure of human impact) negativelly, and (iii), of course, both the growth and dominance are positively affected by nutrient content. Fertility does not differ among the types of invaded habitats, but goes up with the height of I. glandulifera and decreases with its cover. Invaded habitats comprises ruderal and riparian vegetation, but also wet maedows, forest clearances, beach and slope forests or weed vegetation.
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Current state of vegetation in the Sázava River floodplain after spring flood in 2006
Klášterková, Hana ; Chuman, Tomáš (advisor) ; Matějček, Tomáš (referee)
In this diploma thesis current state of vegetation cover was analyzed after spring flood in 2006 on the lower section of the Sázava river. Immediately after the flood there were 38 sites with alluvial deposits identified in the floodplain. The differences in species composition and species diversity between sites with alluvial deposits and sites without deposits were analyzed. The data were collected by using phytosociological relevés in pairs i.e. - plot with an alluvial deposit and plot without. There were 86 vascular plant species recorded out of which 10 species were non-native but not invasive species and 7 species were non-native invasive species. Results of this thesis revealed that species composition and diversity of invasive species differ between plots with alluvial deposits and plots without alluvial deposits. Moreover, plots without alluvial deposits host more invasive species. Keywords: vegetation succession, river floodplain, extreme floods, species diversity, plant invasion
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