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Determination of evapotranspiration from small catchments
Toušková, Jitka ; Šípek, Václav (advisor) ; Možný, Martin (referee) ; Brom, Jakub (referee)
Evapotranspiration (ET) plays a significant role in the hydrological balance. The terms potential (PET) and reference (RET) evapotranspiration are often used while estimating its rate. The doctoral thesis deals with the estimation of PET, RET and other selected processes. First, the influence of net longwave radiation (the component of radiation balance) on the rate of PET was examined. It was found that the standard methods result in the significant differences in PET estimation due to the absence of model calibration to local conditions. The original model caused distinction in the PET evaluation for the Liz experimental catchment by up to 100 mm/year. Calibration of the parameters of two commonly used methods for calculating net longwave radiation reduced the error in PET evaluation to less than 20 mm/year. PET or RET estimation itself can be performed by many direct or indirect methods. Their accuracy is highly discussed. This work focused on selection of suitable methods and their further testing on conditions of 18 stations in the Czech Republic. 37 methods were compared with measured data. It was proven, that the best results in this region were achieved by combination methods (with average RMSE of 1.2 mm/day, 18.6 mm/month, and 33.3 mm/year). Among individual models, the radiation-based...
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Proposal of small earth dam
Stoklas, Jan ; Duchan, David (referee) ; Špano, Miroslav (advisor)
The subjekt of this bachelor thesis is the study of a small water reservoir in a particular locality. It consists of a text part and a drawing part. The text part contains brief summary of the issues of small water reservoirs, description of the locality, determination of design flow, needed hydrotecchnical calculations and design of expected technical solution. The drawings show the design of the dam, the combinated funtional object and the modified flooded area.
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Search and Comparison of Methods for Calculation of Reservoir Storage Yield Analysis
Michálková, Veronika ; Menšík, Pavel (referee) ; Marton, Daniel (advisor)
The ever-increasing threat of climate change is bringing the issue of water resources, both groundwater and surface water, to the fore. Hydrological extremes in the form of floods and droughts have always been there. However, their intensity has increased and they have a much greater scale and impact on life. On the one hand there is a need to retain and store water for further economic use, on the other to transform flood waves and try to prevent the devastating effects of floods. In view of these facts, the aim of this paper is to develop a comprehensive overview of methods for calculating the size of reservoir storage volume, which is one of many tools for effective mitigation in the perspective of combating drought. The text includes methods from both foreign and Czech perspectives. Five methods were applied on the inflow of the Vír reservoir presented by a flow series. Two of the selected ones are sequent peak algorithm which uses sequential balance of inflow and outflow from the reservoir. They are used abroad. The other method is a direct solution to the size of the reservoir storage volume size, which was taken from the study materials at CTU Prague. Also from this area is the progressive balance method and finally the problem of type A.1 is calculated, which appears in the study materials of the Faculty of Civil Engineering of Brno University of Technology. The practical application of the methods also provided a comparison of the results of the calculations and their differences.
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Analysis of Water Consumption in Brno
Růžička, Jaroslav ; Kučera, Tomáš (referee) ; Tuhovčák, Ladislav (advisor)
Water consumption is the amount of water removed by the consumer from water disstribution network. During the transportation inside water disstribution network occur losses. Assesing these losses is one of the main responsibillities of the water supplier. We can show the amount of water lost by using several different methods. Values used to describe the amount of water lost can be often replaced by percentual ratio of water produced to water lossed.
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Methodology for rapid, comprehensive, independent decision-making on the need, effectiveness and interaction of adaptation measures in river basins under climate change
Fischer, Milan ; Zeman, Evžen ; Vizina, A. ; Hanel, M. ; Bernsteinová, Jana ; Tachecí, P. ; Štěpánek, Petr ; Pavlík, P. ; Máca, P. ; Ghisi, Tomáš ; Rapantová, N. ; Bláhová, Monika ; Janál, P. ; Trnka, Miroslav
The aim of the methodology is to present methods for quantifying the impacts of projected climate change on the water balance when applying adaptation measures in the Czech Republic for the next few decades. Adaptation measures should contribute to the sustainability of the water balance in all major user segments of water use and management in the basin. The main principle is the use of hydrological models to transform climate change scenarios into time series of hydrological conditions and to quantify the overall water balance of the basin using different types of adaptation measures and their implementation over time. Special emphasis is placed on the evaluation of combinations of adaptation measures that cannot be analysed by simplified methods. The methodology is designed to search for the optimal combination of adaptation measures in the assessed catchment. The proposed approach eliminates the shortcomings of effectiveness assessment from the perspective of the exclusive user of the water resource, as the evaluation of the effectiveness of adaptation measures is carried out in the form of a multi-criteria analysis of the evaluation of the outputs of the simulation model for predicting the water balance in the whole basin. This methodology can be used to assess different adaptation measures in all basic segments of water users: agriculture, forestry, energy, water management and others.
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Methodology for determining the main disturbances in the water management balance and optimizing adaptation measures in the conditions climate change
Fischer, Milan ; Zeman, Evžen ; Vizina, A. ; Hanel, M. ; Bernsteinová, Jana ; Tachecí, P. ; Štěpánek, Petr ; Pavlík, P. ; Máca, P. ; Ghisi, Tomáš ; Rapantová, N. ; Bláhová, Monika ; Janál, P. ; Trnka, Miroslav
Ongoing climate change is causing a global increase in air temperature. While this is leading to an acceleration of the global hydrological cycle, and therefore a global increase in precipitation, the spatiotemporal variability in precipitation is much more complicated. While temperature in the Czech Republic shows a consistently increasing trend similar to that of surrounding countries and the planet as a whole, precipitation can be simplified that long-term averages of annual totals remain and are likely to remain very similar in the coming decades. Rising air temperatures inherently bring increased evaporative demand of the atmosphere and, for the same precipitation, a lower ratio of precipitation to evaporation, i.e. the climatic water balance shows a negative trend.
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Evapotranspiration of peat soils
Urbánková, Karolína ; Weiss, Tomáš (advisor) ; Šípek, Václav (referee)
The correct determination of evapotranspiration is critical for the calculation of the water balance. Although research on evapotranspiration in general is already quite advanced, peat soils are so specific that they may require their own unique approach. Hydrologists have a series of calculations and models to determine evapotranspiration, but these are not always sufficiently accurate, especially at higher temperatures. The aim of this thesis was to summarise the existing knowledge of evapotranspiration in peat soils and to determine whether the peat layer thickness has an effect on peat evaporation. The thesis presents a survey of methods for determining evapotranspiration that can be applied to peat soils. The laboratory experiment used a split container, one part of which contained peat and the other part had peat only in the top 7 cm, with quartz sand underneath. The two parts were joined at the bottom with gravel and thus permeable to water. The trend of water loss, soil water potential and soil moisture was monitored. Preliminary results show that peat strength has a clear effect on evaporation. Further research would, among other things, look for a specific height of the peat layer for which the underlying material would no longer have an effect. Key words: evapotranspiration, peat,...
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Runoff from a mainly peat bog basin
Vlček, Lukáš ; Falátková, Kristýna
This research focuses on the basin's hydrological regime, where peatlands make up approximately half of the area. Hydrological processes in the peat bog and the surrounding forest were evaluated using the HBV model. The results show that the peatlands significantly increase the water regime fluctuation of local streams. Moreover, water balance shows a lower cooling effect of tree-less peat bogs than forests on organo-mineral soils. Except for a positive ecological aspect, peatland restoration can have a negative hydrological impact on the surrounding landscape and local streams.
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Hydrology of small basins 2023
Hnilicová, Soňa ; Tesař, Miroslav
The book is a collection of scientific contributions to the Conference "Hydrology of small basins". The conference topics were: 1. Changes in the regime of water resources in small basins; 2. Complex monitoring a and water storage balance in small basins; 3. Hydrological extremes (flash floods, drought); 4. Effect of land use and land cover on water balance; 5. Hydrophobicity and transportation processes in soil; 6. Hydrological modelling und uncertainties; 7. Biogeochemical fluxes in a small watershed and eutrophication of surface waters; 8. Mountainous experimental small basins (deposited precipitation, snow regime, …); 9. New methods, techniques and instrumentation in hydrology and hydroecology.\n
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