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Growth dynamics of clonal plants
Štorková, Zdeňka ; Weiser, Martin (advisor) ; Hadincová, Věroslava (referee)
The thesis focuses on the growth of clonal plants. Clonal plants are exceptional due to the formation of both generative and vegetative organs used for reproduction. The rate of growth of the reproductive organs affects the reproductive success of the plant. In this review, I show how these dynamics are determined by clonal organ type, nutrient abundance, environmental heterogeneity and plant competition for resources. These factors influence the duration of reproductive organ formation, as well as their persistence. The energy requirements of both generative and vegetative organ formations introduce trade-offs into the life of clonal plants. What correlations occur in plants in the distribution of energy into vegetative and generative reproduction has received little attention so far. Therefore, this review summarizes information from the available literature on vegetative and generative plant growth and the trade-offs between them. Key words: clonal plants, timing of reproduction, vegetative reproduction, generative reproduction, trade-off
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Allelopathy in constitution of plant communities
Kučera, Pavel ; Weiser, Martin (advisor) ; Hadincová, Věroslava (referee)
Allelopathy, the ability of some plants to decrease the fitness of other plants by secondary metabolites, has been known for a very long time. The scientific community paid great attention to its research. Despite this, there is still a lot of ambiguity surrounding this phenomenon. In the past, the role of allelopathy in the constitution of plant communities had been often overlooked. The situation improved slightly in the past years. Several new articles summarizing information about the ecological aspect of allelopathy have been published. However, there are many unanswered questions about its widespread in plant communities and the degree of its influence on the ecosystem. This bachelor thesis is focused on summarizing contemporary knowledge about the influence of allelopathy, mainly from the ecological viewpoint, and presenting possible directions for future research. There is included a short list of the most common allelochemicals, basic principles of the functioning of allelopathy, its widespread through plant taxa, and its effect on the plant communities, mutualistic microorganisms, and the whole ecosystem. There is also mentioned the role of allelopathy in the process of invasion of alien species and at the end of the thesis, I discussed possible utilization of accumulated information in...
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Study of ecosystem impact of giant hogweed (Heracleum mantegazzianum) invasion
Hladík, Marek ; Pergl, Jan (advisor) ; Hadincová, Věroslava (referee)
The present study deals with ecological impact of giant hogweed (Heracleum mantegazzianum) invasion in Slavkovský les area. Being one of the prominent invasive species with significant impact on human health it has been subjected to a wide research. In spite of that little is known about its impact on the invaded ecosystem. My research was therefore focused on analysis of the ecosystem impact, particulary 1) microclimatic measurements of temperature and soil moisture and their comparisons between invaded and noninvaded vegetation, 2) comparison of germination and survival of model plant species sowed into invaded and noninvaded plots and 3) study of the effect of H. mantegazzianum presence on model species seed production. Results have shown significant alteration of microclimate due to H. mantegazzianum invasion. Further research is needed to resolve what impact it may pose to species in invaded communities. The effect of Heracleum mantegazzianum presence on germination and survival of model species was not significant. Similarly, seed production of model plants was not significantly affected.
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Factors determining distribution of species in dry grasslands
Průchová, Dana ; Münzbergová, Zuzana (advisor) ; Hadincová, Věroslava (referee)
Factors determining distribution of species in semi-natural grasslands Survival and colonization of plant species in fragmented landscapes are topic of many recent studies. Most of them deal with one or just a few species or with overall species diversity. There are also a lot of studies devoted to the effect of abiotic characteristics and other parameters of fragmented habitat patches. Studies that would enable to evaluate behaviour of a large number of individual species are still relatively rare, especially in case of grassland species. Comparison of species traits in conjunction with the knowledge of type of historical land use and abiotic requirements of species can be a key to understanding of current species dispersal and their regional dynamic in fragmented landscape. This method of prediction of species dispersal can be a good implement for landscape planning and conservation of species and also their habitats. Goal of my thesis was to determine which traits of species influence response of species on land-use history in fragmented habitat of dry grasslands. I tried to use effect of land-use history without effect of environmental factors on species composition in phytosociological relevés. Then I tried to explain the reaction of species through their traits. I focused partially on traits...
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Succession after reintroduction of grazing in dry grasslands
Fulínová, Martina ; Münzbergová, Zuzana (advisor) ; Hadincová, Věroslava (referee)
Grazing management is very popular nowadays and number of sites with grazing animals with the aim of restoring the sites is steadily growing. All the effects of grazing on grazed grasslands are not elucidated yet. This thesis focused mainly on the contribution of zoochory to restoration of species rich grasslands on stands cleared from Robinia pseudoacacia and stands cleared from Prunus spinosa brushwood. For the purpose of monitoring changes in vegetation, permanent plots have been established. In order to identify sources of new species occurring in permanent plots, inventory of species growing in neighbourhood of the permanent plots has been done, samples of soil seed bank, sheep buttons and seeds from sheep wool have been germinated in a greenhouse. Monitoring of permanent plots showed reduced regrowth of R. pseudoacacia and P. spinosa. We have also found that greater changes in species composition occurred in more degraded stands than in stands better-preserved. Germinating experiments proved soil seed bank being mainly the image of aboveground vegetation with minor importance to restoration of species rich grasslands. On the other hand sheep seem to be of great use for dispersal of seeds both by epizoochory and endozoochory when walking between different stands. This finding is of great importance for...
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Wildfire as an ecological factor in the forests of Central Europe
Adámek, Martin ; Hadincová, Věroslava (advisor) ; Svoboda, Miroslav (referee) ; Nagel, Thomas A (referee)
Within the Northern Hemisphere, wildfires are considered to be an integral part of natural dynamics mainly in boreal forests and Mediterranean ecosystems, and most recently also in temperate forests of Northern America. By contrast, in temperate forests of Central Europe, the importance of wildfire for forest ecosystems has been traditionally marginalised despite documented frequent wildfire occurrence and existence of fire-prone forests. Apparently, the reason of this rooted attitude does not lie in the specific environmental conditions of Central Europe, but more likely in the traditional forest ecology approach, which generally does not consider the effect of disturbances on the shape of vegetation communities and strictly excludes human activity from natural processes since its beginnings. This attitude resulted in the lack of knowledge about local vegetation-wildfire relationship and patterns of wildfire occurrence in the landscape. The general aim of this thesis was to clarify the ecological role of wildfires for Central European forest ecosystems with a focus on Pinus sylvestris forests and using the Czech Republic as a model area for a broader region. Chapter 1 deals with the spatial analysis of the occurrence of forest fires in the Czech Republic. We found that the presence of wildfire in...
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Long distance dispersal of Rumex alpinus
Řičařová, Veronika ; Münzbergová, Zuzana (advisor) ; Hadincová, Věroslava (referee)
Long-distance dispersal of Rumex alpinus was studied in the Giant Mountain in the National Park. The invasion of R. alpinus is there kind of problem. The work builds on a thesis from year 2007 (20007 Červenková), in which was made the model of the invasion of R. alpinus in the area of the Giant Mountain. The measurements of the seeds spread take place at four localities, three of them were for measuring of water dispersal and one was for measuring of winter dispersal. Anemochory was measured using traps in the meadow up to a distance of 50 m. The seeds were dispersed by wind to a distance of 20 meters. Hydrochory was measured using a network's traps in the streams up to 100 m. The largest measured water dispersal was 100 m. Hydrochory therefore proved to be an important factor, which influenced the invasion of R. alpinus. The storms and flood had the great influence on the hydrochory and anemochory. The prediction exponential curves were compiled from the data about the wind dispersal. The curves express the spread to more than a measured distance. The field dispersion curves were compared with theoretical curves, which were used in the model of the invasion from 2007. It turned out that the theoretical curves overestimate the spread of R. alpinus by wind. The dispersion of seeds was underestimated in the...
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Effects of litter raking on plant-soil interactions
Husinecká, Tereza ; Münzbergová, Zuzana (advisor) ; Hadincová, Věroslava (referee)
Plant litter creates variously sized layer on soil and provides significant source of nutrients, especially carbon and nitrogen, for the whole ecosystem. Decomposition of plant litter forms the main source of soil organic matter and is an essential part of the global nutrient cycle. It also provides habitat for many organisms living on the boundary of soil. Also, plant litter makes a barrier which the light is unable to penetrate. Terrestrial ecosystems are affected by human activity and are subject to disturbances, including litter raking. Litter raking has been an integral part of forest management for several centuries in the past, significantly affecting the character of vegetation and the soil environment. The aim of this work is to summarize the findings of studies dealing with the effects of litter raking on the interaction between plants and soil. The first part of the paper is devoted to the litter, soil environment and its components, which are connected to the litter and second part of the paper is devoted to the effect of litter raking on the nutrient cycle, acidification, plant diversity and seed germination.
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Natural regeneration of Norway spruce in mountain forests and at disturbed plots
Urbanová, Renáta ; Hadincová, Věroslava (advisor) ; Brůna, Josef (referee)
The natural regeneration of Picea abies in undisturbed mountain spruce forests as well as in disturbed areas formed by windstorms and overgrowth of bark beetles, especially spruce bark beetle (Ips typographus), takes place primarily through seed germination from a transitional soil seed bank. The quality of the soil seed bank depends on the amount of seeds available, which varies significantly throughout years, and on environment conditions. Interannual changes in the amount of seeds produced are caused by the irregular occurrence of seed years, which reflects weather changes in the context of ongoing climate change. Increased average air temperature and unevenly distributed rainfalls throughout the year have a positive effect on the spruce phenology, seed abundance and quality and results in increasing frequency of seed years. The large amount of seeds during seed years induces increased abundance of granivores for which the seeds are the source of nutrients and environment for their development. Seed predators of invertebrates and, small vertebrates groups and fungal pathogens significantly reduce the proportion of seeds needed for spruce natural regeneration. This bachelor thesis summarizes up to now knowledge explaining mechanisms and interactions associated with the soil seed bank of Picea...
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