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Siltation of the Jirkov and Křímov water reservoirs
Němečková, Pavla ; Šobr, Miroslav (advisor) ; Chalupová, Dagmar (referee)
This bachelor's thesis contains detailed physical and geographical characteristics of the area and the comparison of the bathymetric methods. In the practical part it is focused on water reservoirs Křímov and Jirkov, which were built in the 1950s and 1960s. The main goal is to find out current conditions of water reservoirs using Acoustic Doppler Current Profiler (ADCP) RiverSurveyor M9 on the float, which offers automatic data saving. The bathymetric maps are created in ArcGIS Pro 3.0.2 by processing the measured data from 2022 and using the Kriging interpolation method. The current volume is compared to data from digitalized historical maps. The difference between these data gives us the amount of sediments and also the change of volume in every depth level. The current volume of WR Křímov corresponds to 1.31 mil. m3 , there was 6.4% silting compared to operating regulations. The Jirkov water reservoir has a current volume of 1.95 million m3 , in comparison to the operating regulations, there was only 3% silting. Key words: WR Křímov - WR Jirkov - bathymetric mapping - siltation
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The analysis of GLOFs database
Kovanda, Matouš ; Vilímek, Vít (advisor) ; Šobr, Miroslav (referee)
In many areas around the world, events occur when a large volume of water is suddenly released from a glacial lake. This event, called a Glacial Lake Outburst Flood (GLOF), can flood a large area under a glacial lake in a short time, posing a major risk to local populations and infrastructure. As there are many diverse factors that influence the occurrence, development and mode of occurrence of such an event, GLOFs are first described in this study, using mainly international literature for the description. In the research part, attention is directed to the analysis of the global database recording the past GLOFs. The GLOFs are divided into areas based on the place of origin, in which their total abundance over the entire period of record, the distribution of abundance in each decade since the early 20th century, and the distribution of abundance within a year are analysed. Attention is also directed to the glacial lakes themselves where the GLOF event occurred. The types and number of glacial lakes, the manner in which the lake spills water, and the number of repeated GLOFs are analyzed. Finally, the resulting values between the different areas are compared with each other and their similarities or differences are observed.
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Concept of stream restoration in urban area
Jonáš, Miroslav ; Matoušková, Milada (advisor) ; Šobr, Miroslav (referee)
This diploma thesis presents a restoration study of a small watercourse in the urban area, specifically the section of Bouřlivec - a tributary of the Bílina River, crossing the municipality of the village Lahošť. The restoration study was carried out as a part of the contract research of the Faculty of Science, Charles University in Prague and Povodí Ohře, state enterprise. The final report of this research is part of the cited literature at the end of the qualification thesis. Among the main objectives of the study was the design of restoration concept that will primarily lead to: 1) improving the hydromorphological and ecological state of the stream, 2) increasing flood protection and 3) increasing recreational usability in close proximity to the watercourse. A total of 11 cross section profiles within a longitudinal profile with a length of approx. 454 m were geodetically measured using the total geodetic station. A modification of the new method of calculating the roughness of cross section profiles was proposed and for each profile the current and design maximum flow capacities were calculated. As part of the longitudinal profile, a mosaic of 4 variant solutions was designed, which alternate regularly within the section of interest. The grain size analysis of the river substrate was held in...
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Monitoring and warnings of hydrological drought in the world
Klečková, Hana ; Šobr, Miroslav (advisor) ; Pecha, Martin (referee)
This bachelor thesis analyzes the definition of hydrological drought and the definition of general drought. The introduction defines the main characteristics of meteorological, hydrological, agronomic and socio-economic droughts and their differences. Furthermore, it points out the causes and impacts of drought in different regions of the world from an economic, environmental and social view. The thesis also summarizes the recent hydrological drought in Czechia, which were the significant dry years 2015 and 2018. Additionaly, the thesis deals with drought in selected regions in the world and describes the most affected areas with drought and water scarcity. Large part is devoted to monitoring and warning systems of hydrological drought in the Czech Republic and in the world. Finally, the thesis explaines the differences between each hydrological model including HBV, VIC, LISFLOOD, Bilan, RAPID and mHM and describes different indexes like TSDI, DSCI, ODIB or CDI index. Keywords: hydrological drought, monitoring of drought, warning services
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Evaluation of the river system of the Odlezelské (Mladotické) Lake basin as a potential source for sediment transport
Mužák, Petr ; Kliment, Zdeněk (advisor) ; Šobr, Miroslav (referee)
The status of the river network is essential to understanding the fluvial system of the basin. Erosion and accumulation activities of the river system led to changes in the river channel which caused the increased sediment transport and contributed to the silting of the Odlezelské (Mladotické) Lake. This study aimed to evaluate the status of the river system of the Odlezelské Lake basin and to identify and characterize its erosion and accumulation of landforms. The field survey of the Odlezelské Lake basin applied the hydro morphological characteristics monitoring (HEM) method extended by the record of erosion and accumulative landforms. The Mladotický stream recorded the highest representation and area concentration of erosion landforms. The Potvorovský stream showed the highest density of accumulation of landforms. Anthropogenic activity changed the mapped part of the lake basin in 47 percent of sections which exhibited a lower degree of erosion and accumulation of landforms. Beaver population activities also significantly influence the fluvial dynamics of the river system. Keywords: river channel, fluvial dynamics, sediment transport, Odlezelské (Mladotické) Lake
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Sediment analysis and hydrological regime of water reservoir Všechlapy
Wolfová, Helena ; Šobr, Miroslav (advisor) ; Kliment, Zdeněk (referee)
This masters thesis is focused on the evaluation of anthropogenic sediment pollution and the total estimate of the siltation of the Všechlapy reservoir. Based on bathymetric mapping, the morphometric parameters of the Všechlapy reservoir were evaluated. By digitizing the old map of the previous terrain before the construction of the dam, its current siltation of 15.7 % with bedload sediment was determined. Bedload sediments and river sediments of two streams were collected, in which the grain size analysis of the fine-grained fraction and the chemical analysis by pseudo-total digestion were performed to determine the content of metals and metalloids. Evaluation of sediment pollution was performed using geoaccumulation index using global and local background values of the natural environment. It was found that the Bouřlivec stream was rated the worst pollution classes in terms of cadmium, arsenic, copper, lead, zinc and nickel. Based on their chemical properties, these increased concentrations were also reflected in the samples taken from the bed of the Všechlapy reservoir. Part of this thesis was also the review of the hydrological regime of the Všechlapy reservoir. key words: sediment pollution, water reservoir Všechlapy, Bouřlivec stream basin, bathymetric survey, aqua regia leaching
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Glacial hydrological regime, case study of lake Adygene (Tien - Shan, Kyrgyzstan)
Beitlerová, Hana ; Šobr, Miroslav (advisor) ; Kocum, Jan (referee)
This thesis is concerned with detailed analysis of glacial hydrological regime and its influencing factors. Knowledges published in the domestic and foreign scientific literature were applied on data acquired in the area of Adygine Lake (Tien - Shan, Kyrgyzstan). The lake is a part of a lake system recently developed in the surroundings of a retreating glacier. There is a potential risk of dam failure in terms of its stability. Lake level fluctuations depending upon climatic conditions, melt water inflow and capacity of subsurface outflow channels were observed. Key words: glacial regime, glacial lake, melt water, glacier melt, diurnal variations, seasonal variations, delay of runoff
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Hydrological regime of selected lakes in the High Tatra Mts.
Sankotová, Tereza ; Šobr, Miroslav (advisor) ; Janský, Bohumír (referee)
This diploma thesis deals with morphometric analysis and hydrological regime of Skalnaté pleso lake and Hincové Oká lakes, especially the lake level fluctuation, during the period 2011 - 2014. One of the tasks was the bathymetric mapping of observed locations. For Hincové Oká lakes was it the first mapping of bathymetry at all. The hydrological regime and lake level fluctuation regime of observed locations shows interesting differences from the other Tatra lakes whose hydrological regime is controlled by precipitation amounts. The annual culmination of Hincové Oká lakes (the largest lake) is shifted into the spring caused by melting snowpack. When there is no rainfall for a couple of days Skalnaté pleso lake often dries up, even during summer months, when levels of most Tatra lakes reach their maximum values. However summer drying is shortterm. Lake level fluctuation regime is very dynamic. After a strong rainfall event its level rises very steeply, up to 0,14 m per hour. Powered by TCPDF (www.tcpdf.org)
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Dynamic of evolution and hazardousness of lakes in the Cordillera Blanca (Peru)
Emmer, Adam ; Vilímek, Vít (advisor) ; Šobr, Miroslav (referee) ; Haeberli, Wilfried (referee)
Adam Emmer: Dynamic of evolution and hazardousness of lakes in the Cordillera Blanca (Peru) Abstract: High mountain environment of the Cordillera Blanca (Peru) is undergoing prespicious (goe)environmantal changes such as glacier retreat and associated formation and evolution of lakes. Glacial lakes may represent a threat for the society in case of sudden release of (part of) retained water ("glacial lake outburst flood"; GLOF). Reliable identification of hazardous lakes is a key persumption of effective GLOF risk management. The fundamental part of this thesis lies in creation of new method for assessing susceptibility of lakes to outburst floods, reflecting regional specifics of these events in the study area (preconditions, causes and mechanisms) and unsuitability of existing approaches revealed in previous research. Newly created method take into account five scenarios of GLOFs, which are assessed separately, using the combination of decision trees allowing integration of qualitative and quantitative characteristics (an overall number of 17 characteristics of the dam, lake and lake surrounding enter the assessment procedure). Thus, identification of specific causes and mechanisms is enabled. The method was verified by assessing susceptibility of 20 lakes, of which 10 produced GLOFs in past (pre-flood...
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