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Antropogenní vliv na biodiverzitu v komplexu Páramos de Santurban (Kolumbie)
Aparicio Vásquez, Diana Libeth ; Sklenář, Petr (advisor) ; Kovář, Pavel (referee)
Paramo is the name of the region encountered in the upper belt (3 000m - 4 800m) of the Andean mountain ridges from Venezuela to the North of Peru. Paramo ecosystem occupies only 2% of the area of those countries. Nevertheless, paramo flora is the richest high mountain flora of the world (over 3500 species, 60% of endemism). High mountain region of the Northern Andes were almost uninhabited until the arrival of the Conquistadores. At the time of the conquest, livestock and new crops were introduced to the Andean ecosystems. Since that time, paramo has been used mainly for extensive cattle grazing and cultivation of potatoes and onions. During the last three centuries an abrupt intensification of the agricultural practices has occurred. The main aim of this study is to investigate the effects of human intervention, by mean of farming, on species diversity of the paramo vegetation. The study area was selected in the paramo belt of Santurban, Colombian Eastern Cordillera. Ordination techniques were applied to analyze the relation between plant species composition, environmental variables and management variables. We found plant species diversity is influenced by cattle grazing and cropping, but the vegetation changes are mainly determined by the altitudinal gradient. Intensity of human impact is also...
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Anatomy and functional ecology of tropical alpine plants in South America
Gorčicová, Barbora ; Sklenář, Petr (advisor) ; Stančík, Daniel (referee)
The bachelor thesis discusses the plants in the páramo. The first part describes unique environment located at high altitudes of the tropical South America, the páramo. The uniqueness of the environment is caused by several basic conditions. The most important ones are significant daily temperature fluctuations, tropical climate stability during the whole year and high altitude. Anatomy of adapted plants, discussed in the second part of this work, conform to the extreme conditions. There are specific páramo life forms thanks to the uniqueness of the environment. The leaf structure and the vascular system of the plants are significantly modified in terms of anatomy. Although there are quite specific (and therefore interesting) life forms in the páramo, the current knowledge of the plant anatomy is minimal. The last part of the thesis suggests the questions for my future master thesis, which will contribute to better understanding of this underexplored topic.
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Ecophysiology of peat bog ericoid subshrubs - freezing resistance and water relations
Daněk, Michal ; Sklenář, Petr (advisor) ; Hájek, Tomáš (referee)
The seasonal changes in freezing resistance and water relations in four dwarf shrub species of Ericaceae family: Vaccinium vitis-idaea, V. myrtillus, V. uliginosum and Oxycoccus palustris in two study areas differing in altitude were studied in this work. To establish the freezing resistance, the plants were sampled eight times, to determine parameters of the water relations, the plants were sampled six times during the growing season of 2009. For the freezing resistance examination, ice nucleation temperature (exotherm) and 50 per cent lethal temperature (LT50) were found. The water relations were described using the parameters derived from the pressure-volume curves: osmotic potential at full turgor, osmotic potential at zero turgor, cytoplasmic water fraction, relative water content at turgor loss and bulk modulus of elasticity. An important seasonal variability in the freezing resistance was found. The highest levels of the freezing resistance were reached in the spring and in the autumn, the lowest levels were found in the summer. There were also changes in the used mechanisms of the freezing resistance - for most of the year, the plants were tolerant, they showed the avoidance mechanism only in the summer. The seasonal changes in the water relation parameter were less unambiguous. The most of...
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Diversity of forest vegetation in the region of České středohoří
Tydlitátová, Klára ; Sklenář, Petr (advisor) ; Hédl, Radim (referee)
Abstract The topography of the Milešov part of the České středohoří Mts represents a suitable model for study of spatial distribution of diversity and the effects of ecological factors on species diversity and composition. Near-natural forest vegetation was sampled at eleven hills by stratified-randomly sited relevés. Soil samples were collected in relevés at nine hills also. The soil samples were used for maximal capillary capability, pH, carbon and nitrogen volume analyses. These ecological factors, as well as tree cover, altitude and heat load index, were used for examination of the correlation of ecological factors with diversity, species richness and species composition. Positive relationship between species richness and heat load index and soil reaction was identified. Species diversity (Shannon index) positively correlates with soil reaction also. After partialling out geographic components in the samples, a significant correlation between the heat load index, tree cover and altitude and species composition of the herb and shrub layer was found. Values of alpha and beta components were rated using partitioning of diversity to alpha and beta components at four levels (relevé - aspect - hill - landscape). The beta component at the aspect level and the beta component at the hill level were...
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Plant-Animal Interactions in an Inselberg Ecosystem: The Effect on Reproduction of Selected Species
Vlasáková, Blanka ; Sklenář, Petr (advisor) ; Porembski, Stefan (referee) ; Jersáková, Jana (referee)
Conclusions This thesis provides detailed insight into plant-animal relationships that are involved in reproduction of inselberg species. The results are interpreted in relation to the ecosystem functioning and they also contribute to the general knowledge on specialization in plant-animal interactions (Chapter 2 and 3), floral resources (Chapter 2, 3, and 5), pollinators' attraction (Chapter 2), relations between diaspore's characteristics and animal dispersal (Chapter 4), and conflicts among plant life stages that follow ovule fertilization (Chapter 4). As Clusia aff. sellowiana dominates the shrub vegetation, the study on its reproduction is the initial step to understanding the dynamics of the shrub patches and potential succession on the inselberg. The nocturnal pollination system of Clusia aff. sellowiana bears unusual characteristics and signs of specialization. Only one pollinator species, a cockroach Amazonina platystylata, was recorded and this species is apparently sensitive to olfactory attraction cues emitted by the flowers. This is the first evidence of pollination system that involves cockroaches as pollinators and is to some degree specialized. Clusia aff. sellowiana is dispersed by small birds. Because its diasporas are consumed by birds and there is a time lag before they are deposited,...
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Proposal for Improvements of Personal Activities in Organization
Tokošová, Irena ; Sklenář, Petr (referee) ; Pokorný, Jiří (advisor)
This master’s thesis is oriented on human resource management. This thesis analyzes the efficiency of the company with a focus on personal character weaknesses, ie. the organizational structure, competence of manager, combination compensation, system of empleyee appraisal and the stress load at work. It contains proposals for solutions on improving work efficiency through personnel changes.
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