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The response of sessile oak and Norway spruce to expected climate change
Pozhidaeva, Daria
The global climate is a complex and constantly changing system. However, during the last decades, unprecedented changes have occurred. In this thesis, the response of two tree species – Norway spruce and sessile oak to the expected rise of CO2 concentration in atmosphere and interactions with nitrogen and water availability were studied. For this purpose, an experiment simulating these effects was conducted in experimental glassdomes located in experimental station Bílý Kříž (Bekydy Mountains). It included planting tree saplings in two glassdomes with different CO2 concentrations – ambient (approx. 400 ppm) and elevated (approx. 700 ppm), manipulated water availability during July and beginning of August (regular watering vs drought stress), and nitrogen fertilization (fertilized and non-fertilized) treatments. Physiological measurements (light-saturated CO2 assimilation, stomatal conductance, transpiration rate, water use efficiency, and chlorophyll index) and elemental analyses (carbon : nitrogen ratio) were conducted at the end of the drought stress period. An increase in CO2 assimilation under elevated CO2 concentration was observed in the sessile oak saplings, whereas the Norway spruce has shown no response or even a decline. Both species have shown an increase in the water use efficiency, especially in the water-limited treatment. However, an increase in transpiration and stomatal conductance was indicated in the case of the sessile oak, while Norway spruce has shown a decline in both parameters. The elemental stoichiometry (C:N) response to an elevated CO2 concentration of the tree species has been insignificant, except for the increase in C:N ratio in the sessile oak in both nitrogen-fertilized treatments and in Norway spruce only under lower nitrogen and sufficient water availability. The results have shown that for each tree species different responses to climate change can be expected, which is most likely affected by its ecological requirements. Therefore, in the case of forest management planning, it is important to take these requirements, as well as possible future changes in climate, into consideration.
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Dostupnost nezávadné vody ve východní Africe
Hošková, Lucie
Hošková, L. Availability of safe water in East Africa. Brno, 2019. Bachelor thesis. Mendel University in Brno. This bachelor thesis deals with the issue of safe water availability in the East Africa region. The main aim of the thesis is to evaluate the success of selected projects in two selected countries, Tanzania and Kenya. Following these projects, the subsequent identification of the most important aspects of effective increase in the availability of safe water resources. This work is a form of literature review of water as a source, water stress, water consumption, distribution, treatment and water pollution. It deals with the delimitation of the region of East Africa, closer to two selected model states, Tanzania and Kenya. Part of the work is focused on specific World Bank projects. This section provides an annotated overview of projects and presents their success and failure. Among other things, utilization of results in practice.
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