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Changes in dry grassland and thermophilous forest vegetation and the species traits explaining these changes
Míšek, Vojtěch ; Münzbergová, Zuzana (advisor) ; Větvičková, Anna (referee)
Calcareous dry grasslands and adjacent thermophilous deciduous forests are important biotopes in terms of biodiversity. They have been shaped by human activity for a long time. Grasslands were grazed or mown, forests were coppiced and the litter was raked. The abandonment of these traditional practices is the main cause why both biotopes are threatened nowadays. A return to these forms of management is essential for the restoration and protection of these communities. In my bachelor's thesis, in addition to the characteristics of dry grasslands and deciduous forests and the factors that influence the vegetation of these biotopes, I deal with species traits that can help explain and predict these changes. Key words: xerothermic grassland, thermophilous forest, vegetation change, species traits.
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Landscape-scale changes in central Europe around the Pleistocene-Holocene transition and the Anthropocene
Prach, Jindřich ; Pokorný, Petr (advisor) ; Kuosmanen, Niina Irina (referee) ; Roleček, Jan (referee)
This thesis investigates the dynamics of the central European landscape. Four case studies, exploring two key periods of environmental transformation: Late Glacial and the Anthropocene, are included. All case studies are connected by the spatial scale of interest: the landscape scale. This scale is targeted not only by the spatial extent of the sampling, but by the essence of the issues investigated, as broadly described in the introduction. The studies use disparate methods and different contexts, which helps to approach such a complex phenomenon - the landscape and its formation. The included studies are dealing with the Last Glacial landscape and vegetation by (1) comparing pollen records using modern analogues (here from Yakutia) and argues that the change at the Late Glacial/Holocene transition may not have been as great as previously thought, because at least somewhere forests may had existed during the Last Glacial being supported by permafrost melting. A follow-up study (2) explores how permafrost melting, i.e., thermokarst processes, generated an entire lake landscape whose remnants unexpectedly largely persist in the Třeboň region (southern Czech Republic) to recent times. This is followed by (3) the use of a detailed palaeoenvironmental record of the discovered lakes and their contexts...
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Forest vegetation changes in the Bohemian Forest during the second half of 20th century
Prach, Jindřich ; Kopecký, Martin (advisor) ; Sádlo, Jiří (referee)
Long-term forest vegetation changes were studied in the Bohemian Forest and its foothills. New vegetation relevés were taken at sites of typological plots established by forest engineers between 1955 and 1980. Data from 158 semi-permanent plots were analysed using modern statistical methods. The data show significant changes and homogenization of the vegetation. Ellenberg indicator values indicate eutrofication. Repeated measurements of soil pH suggest acidification, but the interpretation of these data is complicated by methodological problems. The forests under study exhibit high spatial variability. No main prevailing trend in vegetation changes was found. The changes are considered to be related to sulphur and nitrogen deposition and forest management. The influence of increasing age of forest stands seems to be unimportant. Discussed are not only vegetation changes and their possible causes but also the possibilities and limitations of using such old forestry data in botanical and ecological studies.
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Distribution of invasive neophytes in the riparian vegetation of the Berounka river
Randová, Nela ; Matějček, Tomáš (advisor) ; Romportl, Dušan (referee)
The river banks are very often colonized by invasive alien plants. The aim of this paper was to monitor the presence of invasive neophytes in riparian vegetation of the Berounka river and to compare the results with those of Boháčková (2007) from the year 2006. The research was completed during August in the year 2015. In every segment of the riparian vegetation were observed the presence and approximate population of seventeen invasive neophytes. In the riparian vegetation of the Berounka river were observed thirteen invasive neophytes on the whole. Impatiens glandulifera occured in the largest number of the segments, very closely followed by Robinia pseudacacia. Reynoutria sp. represented the largest population of individuals in the entire study area. The results of the comparison showed that the invasive neophytes are spreading to new locations but their population is not getting bigger. Key words: invasive neophytes, riparian vegetation, stream, changes in vegetation, monitoring of vegetation
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Land-cover changes and climatic settings of the Úpské rašeliniště mire
Hejda, Tomáš ; Treml, Václav (advisor) ; Šefrna, Luděk (referee)
Mires, or wetlands, are very important habitats, ecosystems, as well as relict and recent reserves. The object of the study of mires is focused on morphological, hydrological and chemical characteristics as they are more discussed globally due to climate change. The present thesis deals with the characteristics of mires on a global scale, which are used in literature and make up their classification. The classification of mires is also addressed on the Czech scale with a focus on the Western High Sudetes. Mires of the Giant Mts. were analyzed according to climate conditions with a focus on the dynamics of land cover areas of Úpské rašeliniště mire and subsequently compared with Scandinavian mires. A particularly strong dependence on the Aapa type can be stated from the analysis. The vegetation above the alpine timberline primarily consisting of dwarf pines (Pinus mugo) and spruce families showed a substantial increase with respect to the impacts of climate fluctuations in the recorded period in Eastern High Giant Mts. Key words: mires, classification, Giant Mts., climate, vegetation change
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Distribution of invasive neophytes in the riparian vegetation of the Berounka river
Randová, Nela ; Matějček, Tomáš (advisor) ; Romportl, Dušan (referee)
The river banks are very often colonized by invasive alien plants. The aim of this paper was to monitor the presence of invasive neophytes in riparian vegetation of the Berounka river and to compare the results with those of Boháčková (2007) from the year 2006. The research was completed during August in the year 2015. In every segment of the riparian vegetation were observed the presence and approximate population of seventeen invasive neophytes. In the riparian vegetation of the Berounka river were observed thirteen invasive neophytes on the whole. Impatiens glandulifera occured in the largest number of the segments, very closely followed by Robinia pseudacacia. Reynoutria sp. represented the largest population of individuals in the entire study area. The results of the comparison showed that the invasive neophytes are spreading to new locations but their population is not getting bigger. Key words: invasive neophytes, riparian vegetation, stream, changes in vegetation, monitoring of vegetation
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Land-cover changes and climatic settings of the Úpské rašeliniště mire
Hejda, Tomáš ; Treml, Václav (advisor) ; Šefrna, Luděk (referee)
Mires, or wetlands, are very important habitats, ecosystems, as well as relict and recent reserves. The object of the study of mires is focused on morphological, hydrological and chemical characteristics as they are more discussed globally due to climate change. The present thesis deals with the characteristics of mires on a global scale, which are used in literature and make up their classification. The classification of mires is also addressed on the Czech scale with a focus on the Western High Sudetes. Mires of the Giant Mts. were analyzed according to climate conditions with a focus on the dynamics of land cover areas of Úpské rašeliniště mire and subsequently compared with Scandinavian mires. A particularly strong dependence on the Aapa type can be stated from the analysis. The vegetation above the alpine timberline primarily consisting of dwarf pines (Pinus mugo) and spruce families showed a substantial increase with respect to the impacts of climate fluctuations in the recorded period in Eastern High Giant Mts. Key words: mires, classification, Giant Mts., climate, vegetation change
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Factors determining the vegetation composition of wet meadows and its changes in time
Šimák, Martin ; Münzbergová, Zuzana (advisor) ; Procházka, Tomáš (referee)
This thesis is mainly a literature review of scientific papers and other studies of wet meadows and their characteristics. The aim of the thesis is to summarise knowledge especially of the changes of the vegetation composition of the wet meadows, reveal the causes of such changes and consider the influence of different types of management. Wet meadows underwent crucial changes. They have been drained, the grazing or mowing has ended up and many species were unable to adapt to the changed conditions. Biodiversity in general has been decreasing on these habitats and it has been caused mainly by the total change in management. By comparing different scientific papers I identified common characteristics of the declining species and optimal managment options suitable for stopping their decline were detected. Consequently, I introduce the main methods used to study changes in vegetation composition over time. In the final part of the thesis I mention Slavkovský Les as the area where my future research will be conducted.
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Forest vegetation changes in the Bohemian Forest during the second half of 20th century
Prach, Jindřich ; Kopecký, Martin (advisor) ; Sádlo, Jiří (referee)
Long-term forest vegetation changes were studied in the Bohemian Forest and its foothills. New vegetation relevés were taken at sites of typological plots established by forest engineers between 1955 and 1980. Data from 158 semi-permanent plots were analysed using modern statistical methods. The data show significant changes and homogenization of the vegetation. Ellenberg indicator values indicate eutrofication. Repeated measurements of soil pH suggest acidification, but the interpretation of these data is complicated by methodological problems. The forests under study exhibit high spatial variability. No main prevailing trend in vegetation changes was found. The changes are considered to be related to sulphur and nitrogen deposition and forest management. The influence of increasing age of forest stands seems to be unimportant. Discussed are not only vegetation changes and their possible causes but also the possibilities and limitations of using such old forestry data in botanical and ecological studies.
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