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The frost susceptibility of the soils and materials to subgrade of the pavements
Mašek, Jakub ; Zajíček, Jan (referee) ; Stehlík, Dušan (advisor)
This diploma thesis deals with the issue of the determination of the frost susceptibility of soils in the subgrades of road structures. The theoretical part compares the ways of testing the frost susceptibility in the Czech Republic and other selected countries of the European Union. Furthermore, it also deals with the development of the frost susceptibility index in the Czech Republic. The empirical part focuses on the laboratory testing of the frost susceptibility of the given sample of soil by the direct frost heave method. Moreover, it also deals with the simulation of penetration of frost by the subgrade and the possibility of shortening the length of the freezing during the direct testing the frost susceptibility.
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Posouzení aktuálního stavu kalamitních holin na revíru Buková a potřeb melioračních opatření (lesní správa Černá Hora)
Šmíd, Petr
The topic of the thesis is the water regime in the forest environment at a specific location (Buková district) in connection with the ongoing bark beetle calamity and the associated extensive deforestation of the landscape. After a general introduction to the issue of water in the landscape, the thesis smoothly transitions into a detailed description of the area of interest, i.e. the Buková district, and a more detailed description of the associated forest groups. It captures the period before the bark beetle calamity and compares it with the current period. In addition to the water regime, it also compares the economic situation - the lost profits due to the bark beetle calamity. The paper also evaluates the current land reclamation measures and forest restoration methods using simple methods.
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The influence of water regime and management on the productive capacity of grassland
JANDA, Jiří
The first part of the thesis is devoted to the distribution, importance of permanent grasslands, proper management of grasslands and maintenance of optimal water regime. Water is essential for photosynthesis and plant growth and therefore its availability affects the quantity and quality of biomass produced. The literature on water regime such as rainfall, soil permeability, ground water availability and its effect on grassland production capacity is reviewed. Management techniques such as fertilization and tillage that can help maintain a suitable water and nutrient regi-me for the grassland are also described. In the second and third parts of the thesis, the results of investigating grazed and mown grassland under different water regime and animal load are presented. Furthermore, the climatic conditions of the site are described. The botanical condition of the grassland is elaborated. The influence of the load and water regime on the condition and productivity of the grassland under study is eva-luated. As the water regime increased, the cover of valuable grasses and clovers decreased and the proportion of reticulate and sedge species increased. Measures (fertilization and amendments) were proposed to improve the species composition of the vegetation.
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Possibilities of restoration of endangered wetland biotopes from soil seed bank on example of salt marches
ČÍŽKOVÁ, Eva
Over the past few decades, natural habitats have been massively disrupted and disappeared, resulting in a decline or disappearance of plant species limited to these habitats, thereby the species richness of the area is reducing. However, some plant species produce seeds that retain germination in the soil for a long period of time, so the seed bank may contain species that are no longer situated here or only in a very limited amount in the locality, and therefore the soil seed bank may theoretically be a source of these species and can be used in the restoration of species composition in the locality. In this bachelor´s thesis, a soil seed bank from the largest inland salt marsh in the Czech Republic, located at the southwestern edge of the Nesyt pond in South Moravia, was examined in ex-situ conditions. The subject of the research was mainly the number of individuals of each species germinated from the seed bank. At the same time, it was tested whether the different water level in the substrate affects the abundance of species and species composition of the plants grown from the seed bank. From the soil seed bank of the salt marsh habitat has grown 44 taxa, of which 18 of these taxa are classified as endangered or rare in the Czech Republic. Altogether 1233 individuals of plants were noticed, most of them have been classified as Plantago uliginosa and Juncus compressus, whose individuals constituted more than half of the total number of individuals, while the number of individuals of other taxa ranged from 1 to 10 individuals. Testing the effect of water level on species abundance and species composition showed that more plant species germinated under conditions where the water level was below substrate level than under conditions where the substrate was permanently wetted to flooded.
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Assessment the effect of revitalizing measures of chosen peat bogs in the upper Vydra River basin on their water regime
Doležal, Tomáš ; Kocum, Jan (advisor) ; Kliment, Zdeněk (referee)
Assessment the effect of revitalizing measures of chosen peat bogs in the upper Vydra River basin on their water regime Abstract: Despite a number of research projects, the influence of peat bogs on the hydrological regime remains a largely unexplored topic. In the past, several peat bogs in the Šumava National Park were exposed to a very strong anthropogenic pressure. Subsequently, revitalizing measures were applied to mitigate the impact of human interventions, to stop the degradation of these precious habitats, and to reform the disturbed peat bog water regime. This thesis is focused especially on fluctuations of water table level and on the hydrological regime in the catchments of Rokytka and Cikánský Brooks. Thesis further develops the topic solved in author's bachelor thesis called "Peat bog revitalizing measures and their effect on runoff dynamics in the Otava River headstream area." It contains experimental research of the influence of drainage canals and revitalizing measures on water table fluctuation. It also aims to identify the extent to which meteorological factors contribute to changes in groundwater level and to assess the present state of revitalization measures and their influence on the runoff regime. Key words: peat bogs, revitalizing measures, Šumava Mountains, water regime
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Soil water regime of reclaimed and unreclaimed post mining heaps
Cejpek, Jiří ; Frouz, Jan (advisor) ; Moldan, Bedřich (referee) ; Tesař, Miroslav (referee)
This PhD thesis compares the water regime of reclaimed and unreclaimed spoil heaps after brown coal mining, with special regard to the development of hydrological properties of soils, which are determinant for the movement and retention of water in the soil. The basic influence on the supply of soil water has the technology of pouring the spoil heaps and aging, which co-regulates the development of vegetation. During the development of soil's spoil heaps increases field water capacity and water retention, but also increases the wilting point. These changes are related to the accumulation of organic matter in the soil and the degradation of claystones to particle size of physical clay. The development of the ability of the spoil heaps soils to bind water is greater in reclaimed areas, where the upper organomineral horizon develops more rapidly, but there is also a wilting point and water consumption. On unreclaimed area, the soil substrate develops more slowly. Overall, the differences in water regime between reclaimed and unreclaimed areas are small.
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How does the current climate change affect the phenology and physiology of selected Central European flood-plain forest tree species?
Vokálová, Karolína ; Lhotáková, Zuzana (advisor) ; Konrádová, Hana (referee)
Floodplain forests are biodiversity-rich ecosystems found in many parts of Central Europe near watercourses and are part-time flooded during the course of the year. Floodplain forests are currently facing changes in environment related to climate change, for example increasing temperature and drought, elevated CO2 levels and excessive flooding. Woody plants respond to these changes by shifting the spring phenological phases, increasingly earlier onset of bud break occurs among different tree. Furthermore, there are various physiological, anatomical and morphological adaptations to these changes, through which plants try to avoid their damage. The plant response to changing environment is influenced by many endogenous factors, such as the degree of tolerance to flooding, the type of wood structure, position of a species on the isohydry-anisohydry scale or plant age, in addition to external factors, to which an extent of stress factor effect and its duration belong. In the future, a further increases in the average temperature, the CO2 concentration in the atmosphere and above-average flooding are expected, therefore it is important to understand the complex reactions and adaptations of floodplain forest trees to these changes in order to manage effectively these ecosystems.
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Soil water regime of reclaimed and unreclaimed post mining heaps
Cejpek, Jiří
This PhD thesis compares the water regime of reclaimed and unreclaimed spoil heaps after brown coal mining, with special regard to the development of hydrological properties of soils, which are determinant for the movement and retention of water in the soil. The basic influence on the supply of soil water has the technology of pouring the spoil heaps and aging, which co-regulates the development of vegetation. During the development of soil's spoil heaps increases field water capacity and water retention, but also increases the wilting point. These changes are related to the accumulation of organic matter in the soil and the degradation of claystones to particle size of physical clay. The development of the ability of the spoil heaps soils to bind water is greater in reclaimed areas, where the upper organomineral horizon develops more rapidly, but there is also a wilting point and water consumption. On unreclaimed area, the soil substrate develops more slowly. Overall, the differences in water regime between reclaimed and unreclaimed areas are small.
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