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Landscape structure, habitat properties, species traits or chance: What determines distribution of grassland plants in abandoned fields?
Knappová, Jana ; Münzbergová, Zuzana (advisor) ; Hájek, Michal (referee) ; De Bello, Francesco (referee)
Semi-natural grasslands are among the most threatened habitats in Europe, endangered mainly by cessation of former management practices and conversion into other types of land use. Extensive research has been carried out in European grasslands in last decades, to explain origins of diversity and to provide guidelines for its conservation. However, the very slow response of perennial plants to landscape changes often impedes to accurately evaluate why species occur just where they occur and not elsewhere. Abandoned fields are perceived as potential habitats for species from declining grasslands. Indeed, many species are able to spontaneously colonise abandoned fields, but many other species are absent from communities that develop there. An important question remains what limits their successful establishment. By answering this question, we can gain also important insights into factors determining species distribution in grasslands because colonization of recently abandoned fields by grassland species is the ongoing process which is not obscured by historical changes in landscape structure. The very basic aim of this thesis was to evaluate the status quo of dry grassland plants in fields abandoned in last two decades. And in the second step, to identify what are the main constrains of successful...
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Grassland restoration in abandoned quarries by sowing seed mixtures
Strušková, Eliška ; Kuťáková, Eliška (advisor) ; Knappová, Jana (referee)
There are many former or still active quarries in the Czech Republic that had disrupted the natural landscape. Under certain conditions, species-rich herbaceous communities can develop in abandoned quarries and these can also serve as a refuge for species that slowly disappear from our landscape due to human activity. In order to create suitable conditions for establishing valuable habitats, it is necessary to choose thoroughly the method of recultivation. Since abandoned quarries are frequently isolated from natural seed resources, sowing of regional mixtures is one of possibilities of recultivation. This bachelor thesis deals with all the steps of this method of recultivation, from the importance of seed origin and their composition in a mixture, through the method of seed collection, methods of sowing, to the combination of seed sowing with the other approaches supporting recultivaton. Keywords: recultivation, abandonded quarries, ecological restoration, seed sowing, semi-natural vegetation
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Importance of biotic and abiotic components in feedback between plants and soil
Hanzelková, Věra ; Pánková, Hana (advisor) ; Knappová, Jana (referee)
The plant-soil feedback affects the forming of a plant community. Plants affect their own species as well as other species. The plant-soil feedback can be both positive and negative. Plants affect soil, change its properties, and the soil affects the plants reciprocally. Soil components can be divided into biotic and abiotic ones. The abiotic component is represented by physical and chemical properties of the soil. The main properties are the soil structure, the soil moisture, the soil temperature, the soil pH and the amount and availability of nutrients. The biotic component is composed of soil biota. The individual organisms can function as decomposers, symbionts and pathogens. The majority of soil organisms is composed of microorganisms, the most important of which are fungi and bacteria. The effect of the abiotic component in plant-soil feedback is mostly nonspecific, while the effect of the biotic component is more specific. These components interact with each other and determine the resulting effect on the plants and the type and intensity of interaction between various plant species. The aim of this thesis is to show the importance of these components in the plant-soil feedback. Key words: plant-soil feedback, abiotic factors, biotic factors, soil structure, soil water, soil temperature, pH,...
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Comparison of three trials used for assassement of ability to disperse by wind and its importance for colonazition of abandoned fields in Asteraceae species
Vlasta, Tomáš ; Knappová, Jana (advisor) ; Kotilínek, Milan (referee)
Several methods are used for studying seed dispersal (seed traps, tracking individual seeds, tracking seeds coloured by fluorescent colours, etc.) However, only a few studies compared results obtained by several methods. In first part of this master thesis, I compared the three above mentioned methods used for studying seed dispersal using species from Asteraceae family. From previous research within the study area (Úštěcko), it is known that dry grassland species are able to colonize abandoned fields. Using seed dispersal data obtained within this theses, I tried to assess the role of seed dispersal on distribution of dry grassland species on abandoned fields both on local and regional scale. The results showed that dispersal curves obtained by the three methods differ significantly. This results may be due to different wind conditions during the experiments. Seed trap data show results from long-term seed dispersal influenced by highly variable wind conditions. In contrary, seed release experiments showed results based on single dispersal event under limited wind conditions. Tracking seeds coloured by fluorescent colours was shown to be not convenient for small seeds, but I can recommend this method for larger seeds. Influence of seed dispersal ability on abundance of dry grassland species on...
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Methods for studying seed dispersal and its importance for colonization of new sites
Vlasta, Tomáš ; Knappová, Jana (advisor) ; Hemrová, Lucie (referee)
Study of seed dispersal is crucial for understanding of several processes in life of plants and landscape. Seed dispesal is very important for persistence of local populations in fragmented landscape, it plays an important role in succession, it helps to protect plant populations againts loss of genetic variability. We usually recognize several types of seed dispersal depending on vector (dispersal by wind, animals and water.) In nature, it is very common that seed can be independently dispersed by several vectors. Therefore, studying of polychory and secondary dispersal is necessery. Methods of studying of seed dispersal are very variable, including seed traps, releasing and following individual seeds, genetics marcers etc. If we study seed dispersal, we should select the most suitable method depending on the aim of the study. We should also take into acount advantages and disadvantages of single method.
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Landscape structure, habitat properties, species traits or chance: What determines distribution of grassland plants in abandoned fields?
Knappová, Jana ; Münzbergová, Zuzana (advisor) ; Hájek, Michal (referee) ; De Bello, Francesco (referee)
Semi-natural grasslands are among the most threatened habitats in Europe, endangered mainly by cessation of former management practices and conversion into other types of land use. Extensive research has been carried out in European grasslands in last decades, to explain origins of diversity and to provide guidelines for its conservation. However, the very slow response of perennial plants to landscape changes often impedes to accurately evaluate why species occur just where they occur and not elsewhere. Abandoned fields are perceived as potential habitats for species from declining grasslands. Indeed, many species are able to spontaneously colonise abandoned fields, but many other species are absent from communities that develop there. An important question remains what limits their successful establishment. By answering this question, we can gain also important insights into factors determining species distribution in grasslands because colonization of recently abandoned fields by grassland species is the ongoing process which is not obscured by historical changes in landscape structure. The very basic aim of this thesis was to evaluate the status quo of dry grassland plants in fields abandoned in last two decades. And in the second step, to identify what are the main constrains of successful...
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DHL as a transport provider with focus on the automotive industry
Knappová, Jana ; Novák, Radek (advisor) ; Bouchal, Martin (referee)
The aim of this diploma thesis is to present DHL as a lead logistics provider for the automotive company Jaguar Land Rover. It is focused on the activities of transport plannning and vendor management. At the beginning, there is an analysis of the logistics contract and its content. The next part is focused on the specifics of international transport planning and the role of vendor management. It also describes the company information systems used for transport planning. The practical part of this thesis identifies the main problems and proposes possible solutions. Finally, there is an assessment of DHL as a logistics provider for Jaguar Land Rover
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Socioekonomická charakteristika Srí Lanky
Knappová, Jana ; Jeníček, Vladimír (advisor) ; Horký, Ondřej (referee)
Práce se zaměřuje na socioekonomickou charakteristiku Srí Lanky. V první části je stručně popsána historie, druhá se zabývá etnickým konfliktem mezi Sinhálci a Tamily, v další části je charakterizována současná ekonomická situace na Srí Lance včetně zahraničního obchodu a spolupráce s ČR. Na závěr jsou uvedeny obchodní zvyklosti a kulturní specifika země.
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