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6 Abstract In recent decades the field of fluvial geomorphology has moved towards the most detailed and comprehensive description of the processes in fluvial systems. The recent development of UAVs (Unmanned Aerial Vehicles) has been a major contribution in analysis of fluvial processes, it provides very detailed data for change analysis. This thesis deals with the analysis of recent fluvial dynamics using UAV. The theoretical part of the thesis summarizes the current theoretical and methodological knowledge from the study of fluvial dynamics and also presents the general principles of UAV monitoring with its use in fluvial-geomorfological research. Recent fluvial dynamics was evaluated in the stretch of Javoří brook in Šumava Mountains where the long-term research is conducted by the Department of Physical Geography and Geoecology. Causal runoff events with an impact on fluvial dynamics were identified on the basis of the analysis of hydrometeorological data covering hydrological years from 2016 to 2020. A total of fourteen events exceeded the threshold of channel-forming discharge Q = 5,041 m3 ·s−1 in the investigated period. Geometrical, morphological and volume changes were evaluated based of the photogrammetric reconstruction of the riverbed during three successive scannings (2015, 2018, 2020). The...

This master thesis deals with the issue of low-flows in mountain catchments in the context of expected climate change. The Zdobnice, Vydra and Mumlava river basins are selected for analysis. In the first part of thesis, the meteorological and hydrological historical data are evaluated. This data are obtained from CHMI (Czech Hydrometeorological Institute). The work also focuses on estimating the possible change in flow rates in the distant future (2100). For these purposes, the conceptual model HBV is used. This model is often used for these types of analyzes due to its robustness. To evaluate the change, twelve alternative scenarios were created. These scenarious were based on the results of global and regional climate models related to each selected river basins. The model was calibrated using the automatic GAP optimization function. Based on the best results, the calibration period is set for the years 1980 - 1998. Climate models suggest increase of temperature in far future by 1.5 ř C - 4.5 ř C. At the same time, according to climate models, we can approximate a total precipitation change by 10 %. Based on climate changes, a shift in the runoff seasonality in the all river basins is evident. Seasonality change is most visible in the Zdobnice river basin. In terms of hydrological drought, an...

The bachelor's thesis entitled Depiction of natural and anthropogenic disasters in the contemporary audiovisual environment - (main Czech news broadcast ČT, Nova, CNN Prima News) deals with media segments of main Czech news broadcast dedicated to disasters. The theoretical part includes a definition of catastrophes as events, offers a short historic outlook on the beginnings of their portrayal in audiovisual news media, and covers the main transformations of the role journalists while working on them. It also describes the latest technology, problematic elements in broadcasting and psychological influence of audiovisual news reporting on disasters. The main part of the examination is to analyse the depiction of the floods 2020 in the Czech Republic, Australian bushfires 2019-2020, and hurricane Laura 2020 in the United States of America. These events represent domestic and foreign disasters. The work also offers brief characteristics of selected broadcasts and disasters. The work aims to contextualise chosen problematic, analyse and compare related segments in selected broadcasts. The work uses methodology of content analysis and comparison. It is a case study.

The main object of this bachelor is the assessment of rainfall-runoff processes with a primary focus on the occurrence of extreme hydrological phenomena in the upper basin of the Ostravice river. The first part of the work is devoted to literature research dealing with the issue of extreme hydrological phenomena and their assessment methods, supplemented by research about current findings regarding changes in the rainfall-runoff regime. This part ends with a description of the physical-geographical conditions of the basin, ilustrated by map outputs. In the second practical part, the available data of average daily flows and daily precipitation totals from the ČHMÚ are analyzed in the period 1970-2020. By Pettit's test of homogeneity, the period is divided into two parts (1970-1995 and 1996-2020) to analyze the change in seasonality of the runoff regime and extreme events. Attention is also paid to the change in the ratio of base and direct runoff using the baseflow index and the runoff coefficient. To detect changes in the characteristics of the frequency of occurrence, duration and intensity of extreme events, the threshold value method and the insufficient volume method were used. As a result, a shift in the seasonality of the occurrence of floods to earlier months and a significant increase in...