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Study of the European green lizard, Lacerta viridis, and ecologically interconnected reptile species in the Czech Republic
Chmelař, Jan ; Rehák, Ivan (advisor) ; Vojar, Jiří (referee) ; Moravec, Jiří (referee)
The European green lizard, Lacerta viridis (Laurenti, 1768), is protected in the Czech Republic as critically endangered. Its distribution in the Bohemia region is restricted to small isolated local populations which are located beyond the northern border of continuous range of the species and are closely related to very specific biotopes. We analysed the distribution of the species both on a national and microhabitat scale and created a predictive model of the species distribution. The most relevant factors influencing the species distribution in the Czech Republic were: annual precipitation, terrain slope, average temperature of the warmest quarter and precipitation in the coldest quarter. On the microhabitat level, individuals selected their immediate vicinity with respect to elevated stones/tree stumps, shelter availability and a proximity to shrubs. Places with high percentage of grass and high vegetation were not preferred. Furthermore, we analysed distribution of selected reptile species ecologically interconnected with Lacerta viridis and identified their preferred habitats. We selected the dice snake, Natrix tessellata, the sand lizard, Lacerta agilis and the smooth snake, Coronella austriaca. All created models are compatible with published data and are applicable in both theory and...
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Visual representation of the climate change in online news
Čermáková, Kristýna ; Lábová, Sandra (advisor) ; Silverio, Robert (referee)
The thesis focuses on journalistic photography in news articles about climate change. In the theoretical part it anchors concepts such as the effects of climate change and its impact on society, explains the workings of stereotypes and solution journalism. It also focuses on fixing the definition of environmental photography and describes the workings of newsrooms, gatekeeping and agenda setting. It will then use a form of mixed quantitative and qualitative research to answer the research question of what photographs are selected for articles about climate change around the world. In the quantitative part, it will use content analysis to map three hundred photographs from three Czech media outlets, A2larm.cz, Novinky.cz and Seznazpravy.cz. The thesis will explore the hypotheses that visually impressive photography will have more space regardless of the weight of the topic, and that stereotypical methods of sampling will predominate when using illustrative images. The qualitative part will answer the research question through three semi-structured interviews and then form a conclusion in the form of an grounded theory. This will reflect on the relationship of Czech newsrooms to the use of photography as an information medium for climate change issues, the possible agenda setting or the journalist's...
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Reakce sazenic břízy bělokoré (Betula pendula Roth.) na stres suchem
Orlovský, Vít
Climate change, with its accelerating intensity, is the primary factor to which forest and urban stands need to respond. Particularly more frequently, recurrent periods of drought, coupled with rising average annual temperatures, mainly in urban development, represent a significant plant stressor. As silver birch (Betula Pendula Roth) is a frequently used tree in urban plantings, the aim of this work was to assess the physiological response of silver birch seedlings after the completed leaf development to stress by drought. Evaluation of the response of the seedlings to stress confirmed the assumption that water potential decreases as the drought increases. Due to the stress of the drought, we saw an 86% decrease in water potential measured at noon compared to the beginning of the experiment. From the results of a 17-day experiment, we found that stress from drought caused a 96% decrease in the rate of photosynthesis and stomatal conductance. So birch seedlings reacted very sensitively to drought stress by trying to avoid reducing water potential. When comparing the variability of the responses of individual seedlings, the physiological parameters showed a marked difference in their response to stress by drought. For example, for rate of photosynthesis, the coefficient of variation for stressed seedlings reached 97% at the end of the experiment. The PRI reflectance index, which indirectly characterises the carotenoid content, showed a coefficient of variation of even 306%. All this information provides us with clear evidence of the ability of individual birch seedlings to react to drought stress in a different way. Based on our measurements and subsequent results, we can conclude that the variability of silver birch seed material is able to respond to the demands implied by the projected climate change.
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The altitudinal dependence of long-term surface air temperature changes
Krauskopf, Tomáš ; Huth, Radan (advisor) ; Pokorná, Lucie (referee)
The altitudinal dependence of long-term surface air temperature changes Abstract In this work there is summarized the scientific literature which is focused on the spatial distribution of long-term surface air temperature changes, specifically on the altitudinal dependence of warming rate. In this text this dependence is analyzed both globally and in several major mountain regions. The greatest attention is paid to the Swiss Alps, where is the largest network of weather stations and there should be achieved reliable results. Furthermore, this work refers to mechanisms that cause different rates of warming at different altitudes, such as snow-albedo feedback or changes in the frequency of fog and cloud. The aim of the practical part is then to analyze surface temperature trends in the Czech Republic and to assess the altitudinal dependence of long-term surface air temperature changes in our country. Keywords: climate change, temperature, trends, altitude
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Long-term changes in Arctic sea ice
Lysenko, Anastasia ; Huth, Radan (advisor) ; Margold, Martin (referee)
The thesis summarizes the knowledge of sea ice in the Arctic, its properties, conditions and the process of formation. It also describes the Arctic climate and its changes since the early 20th century. The work shows how and why Arctic sea ice is important for the climate of our entire planet and that the climate system is highly interconnected. This means that if, for example, there are fundamental changes in the sea ice cover or climate, then the impact of these changes may manifest itself in a completely different area, which is a manifestation of the so- called cascading tipping point. Therefore, this work also touches on the topic of feedback and shows that determining the amount and type of sea ice in the Arctic Ocean is essential to improve our knowledge and understanding of polar weather and long-term climate fuctuations. Key words: climatic change, sea ice, temperature, Arctic
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Evaluating drought risk for permanent grasslands under present and future climate conditions
Trnka, Miroslav ; Schaumberger, A. ; Formayer, H. ; Eitzinger, Josef ; Hlavinka, Petr ; Semerádová, Daniela ; Dubrovský, Martin ; Možný, M. ; Thaler, S. ; Žalud, Zdeněk
Over the past years, the changing climate has affected parts of Czech Republic and Austria by drought spells of the intensity and extend that was unprecedented in previous decades. These events had a significant impact on agricultural areas, especially on the grasslands. The idea behind the GIS monitoring relies on hypothesis that the effect of weather and climate conditions on the grassland production can be estimated by models that describe certain natural processes in a simplified manner and in spatialized form.
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The altitudinal dependence of long-term surface air temperature changes
Krauskopf, Tomáš ; Huth, Radan (advisor) ; Pokorná, Lucie (referee)
The altitudinal dependence of long-term surface air temperature changes Abstract In this work there is summarized the scientific literature which is focused on the spatial distribution of long-term surface air temperature changes, specifically on the altitudinal dependence of warming rate. In this text this dependence is analyzed both globally and in several major mountain regions. The greatest attention is paid to the Swiss Alps, where is the largest network of weather stations and there should be achieved reliable results. Furthermore, this work refers to mechanisms that cause different rates of warming at different altitudes, such as snow-albedo feedback or changes in the frequency of fog and cloud. The aim of the practical part is then to analyze surface temperature trends in the Czech Republic and to assess the altitudinal dependence of long-term surface air temperature changes in our country. Keywords: climate change, temperature, trends, altitude
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Atlantic thermohaline circulation, its possible future changes, and influence on European climate
Krejčová, Zuzana ; Huth, Radan (advisor) ; Šobr, Miroslav (referee)
Atlantic thermohaline circulation, its possible future changes, and influence on European climate This thesis deals with the changes in thermohaline circulation and is mainly focused on the Atlantic meridional circulation. The thesis also explains some basic concepts that relate to the thermohaline circulation. At first the text addresses its effect on the climate in Europe, how climate changes when occurs a change in the Atlantic meridional circulation. The thesis describes the development of the thermohaline circulation in the past, especially approximately 12,000 years ago. It is trying to explain the sudden climate change in response to changes in thermohaline circulation and it is also trying predict the future evolution of the Atlantic meridional circulation. Finally, there are several possible scenarios for the future. The goal of the practical part was to see how and if the average daily maximum and minimum temperatures are dependent on longitude. On the basis of this dependence may indirectly determine the effect of the thermohaline circulation on the climate. Keywords: thermohaline circulation, climatic change, Atlantic meridional overturning circulation
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Climatic change effect on hydrological drought in the Otava River headwaters
Šachová, Barbora ; Kocum, Jan (advisor) ; Fiala, Theodor (referee)
CLIMATIC CHANGE EFFECT ON HYDROLOGICAL DROUGHT IN THE OTAVA RIVER HEADWATERS Abstract The submitted thesis deals with hydrological drought in condition of climate change in Otava River headwaters. The topic is discussed from four different aspects that together create a complex view on the hydrological drought issues in the catchment. The first aspect, the hydrological drought analysis in daily series, is done by threshold level method and SPA. Second aspect studies the impact of climate change on the hydrological drought by using the BILAN model. Following aspect determines a prediction of low flows and deficit volumes during drought by the recession analysis. Final aspect suggests relating process of management, planning and adaptation measures on drought. Key words: hydrological drought, minimal discharges, deficit volumes, BILAN model, climatic change, recession analysis, Otava River, Modrava, Rejštejn, Sušice, adaptation measures
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The temperature and precipitation course in Prague-Karlov, 1961-2010
Střeštík, Jaroslav
The course of temperatures and precipitation in Prague over the last 50 years is presented and compared with scenarios of the further development of the climate. The temperature increased significantly and this increase is more rapid than that of the global temperature. Precipitation totals display only very small decrease over the last 50 years. However, precipitation totals in spring decreased more than the annual sums and a remarkable decrease of days with heavy rainfall takes place. These facts contribute to the observed decrease of the amount of moisture in nature and to the increased occurrence of droughts. There is no indication that all these observed trends could be different in future.
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