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Verification of the dependence between rain intensity and N-year flow for selected river basins with measurement
Tomášek, Lukáš ; Zemanová, Šárka (referee) ; Kozel, Tomáš (advisor)
The diploma thesis deals with the verification of various precipitation events in the selected river basins with measurements. As part of the work, schematization is for a given river basin made and a precipitation-runoff model is created and calibrated based on measurements in the final profile for 2 variants of calculations. Alternative rain intensities with different periodicity and duration are then tested on the calibrated precipitation-runoff model to achieve the required flow rate Q20. Finally, the aforementioned results are evaluated and recommendations are made from them.
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Precipitation and water runoff in the catchment with mosaic of arable land, forests and built-up areas
SCHWARZOVÁ, Monika
This thesis examines the influence of land cover and land use on rainfall-runoff patterns in small catchments. The literature review presented the rainfall-runoff process in general, runoff and the factors that influence runoff. In the practical part of the thesis, the different months of the 2018 study period were presented and converted into graphical form and the differences in rainfall-runoff ratios for two delineated small catchments with significantly different landscape cover were discussed. Specific surface water runoff from catchments with purely forest cover and catchments with a mosaic of cropland, forest, grassland and built-up areas were compared. Runoff responses to rainfall events were also monitored. Measurements of water level in the watercourse with an ultrasonic water level sensor and measurements of water velocity in the watercourse with a hydrometric propeller were used to calculate specific runoff rates. A boat rain gauge was used to measure precipitation. The results showed that the specific runoff from watersheds with forest cover is generally lower and slower due to interception and increased surface roughness compared to runoff from watersheds with a mosaic of cropland, forest, grassland and developed areas. Forest cover in the catchment reduces and slows runoff, particularly during shortterm significant rainfall episodes, and helps to maintain stable runoff from the landscape during drought episodes. In general, the results indicate the importance of vegetation in the landscape for its hydrological characteristics. Finally, modifications to improve the conditions in these small catchments were suggested.
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Analýza srážko-odtokových vztahů na vybraném povodí
FREJLACHOVÁ, Dagmar
This bachelor is focused on analysis of rainfall-runoff relationships. The theoretical part of the thesis defines water in nature, hydrological balance, the rainfall-runoff process, and characteristics of its parts. Rainfall-runoff events and ways of analysing the relationships between rainfall and runoff are also described. The practical part is focused on analysis of rainfall-runoff relationships on the catchment of Jenínský stream in the hydrological years 2011-2013. Description of the catchment, processing of the rainfall and runoff data, creating of hydrographs and runoff coefficients for each hydrological year and selected rainfall-runoff events are part of the thesis as well.
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Modeling hydrological response of the catchment to various precipitation events
ŠVANDA, Dominik
This thesis deals with the simulation of the hydrological response of a river basin to various precipitation events. The hydrological response was simulated in the Olešenský brook basin. The outflow of water from the landscape is influenced by many different factors at the same time. Among the most important factors are, for example, the slope of the terrain, land use, saturation of the soil profile withwater, anthropogenic influences, vegetation cover and last but not least the geological and soil conditions, the shape and area of the river basin, climatic conditions etc. explained and described in detail. Several methods are used to calculate the water runoff from the landscape, in which case the CN curve method was used to calculate the direct runoff from the landscape. By using the BPEJ map, land use and maximum daily precipitation totals with a probability of repeating N years (2, 10, 20, 50 and 100 years) obtained from the rainfall station Týn nad Vltavou, calculations were performed first in a numerical (vector) way and then the maps of direct water runoff from the catchment area were created in a raster way performed in ArcMap software. In the next step, various scenarios were simulated that influenced the outflow of water from the catchment. The first scenario was a change in soil saturation with water, resp. water content in the soil (dry, medium and wet). It has been found that the outflow of water from the basin and the peak flow were both fundamentally changed. Second scenario was grassing of all arable land in the basin, where the actual state compared to the theoretical state. This change reduced the CN curve values, what in turn reduced the direct water runoff from the landscape. Third and the last scenario was the concept of 20 metres wide infiltration strips along roads, watercourses and water areas. The proposed measure reduced the runoff coefficient values by about 1 % compared to the runoff coefficients at the actual state. In this case, there was no fundamental change as the strips occupy only a small part of the total area. However, infiltration strips still have a positive effect on rainfall-runoff events in the landscape.
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Land cover changes in Ore Mountains and their possible impact on rainfall-runoff process
Kratochvílová, Petra ; Jeníček, Michal (advisor) ; Královec, Václav (referee)
Land cover changes in Ore mountains and their possible impact on rainfall-runoff process Abstract Land cover changes have occurred since the formation of Earth, but increasingly, these changes mainly in anthropogenic characters, a big problem in many places around the world. It is, therefore, necessary to monitor how land cover changes, and its impact on individual natural processes and use these results of studies in preventing or fix possible consequences of these changes. More and more disciplines are, therefore, also examines this issue. This paper deals with the assessment of land cover change and its impact on rainfall- runoff process, focusing mainly on mountain basin where this influence manifests itself most expressive, both influencing the water balance of the basin, and influence responses to extreme hydrological events. The findings are applied to the upper basin Chomutovka in the Ore mountains where the thesis evaluates changes in land cover on the basis of aerial photos from 1975, 1987 and the present day (2010). Changes are visualized using digital vectorization and color differentiation of areas of individual land cover types, further processed into a map series and subsequently quantified. According to the results are established the major factors of possible rainfall-runoff processes in...
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Variability of hydropedological characteristics in model catchments of Blanice River headwater area
Kozáková, Jana ; Kliment, Zdeněk (advisor) ; Královec, Václav (referee)
In this thesis are based on the scientific literature defined selected hydropedologic characteristics and is described their impact on motion and amount of water.in the soil and also on the runoff process. In this thesis are quoted methods that can be used for measuring motion and amount of water. Data obtained on several field campaigns and continuous measurement of soil moisture sensors Virrib was processed. Field campaign took place in catchments of Zbytinský and Tetřívčí stream, which are paired comparative experimental catchments. The continuous soil moisture was measured at three places, which differ in their vegetation and soil cover. Data Analysis was concentrate to evaluate soil moisture measured by Virrib, which were compared to soil moisture determined during field campaigns. The continuous soil moisture was measured at three places, which differ in their vegetation and soil cover. The results show that differences and similarities in the vegetation and soil cover greatly reflect on soil moisture. Subsequent comparison of two differently obtained soil moisture should show that the values obtained from Virrib are representative. But comparations of values discover, that in Virrib measurement can be found some inaccuracies. Keywords: hydropedological characteristics, runoff process,...
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Hodnocení základních prvků srážko-odtokového procesu vybraného lesního mikropovodí na území ŠLP ML Křtiny
Šteflová, Gabriela
The thesis is focused on the evaluation of rainfall-runoff process on three stabilized micro-watersheds with different tree species in forest stand, which cover spruce, beech and mixed forest stand, located in the uplands. River basin has been investigated under the same climatic conditions during the growing season 2015. Examined micro-watersheds is located in the FTE Křtiny. This thesis include evaluation of basic statistical parameters and assessment of extreme event for particular watersheds. The work also includes a literature review on the topic parameterization rainfall-runoff process and a description of the experimental watershed. The results indicate that the highest water management efficiency (best parameters of the runoff process)obtains a catchment area of beech stand, while the worst parametrs obtains the spruce watershed.
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Analýza srážko-odtokových procesů a erozních charakteristik vybraného povodí při různém uspořádání krajiny
VANČUROVÁ, Lenka
The diploma thesis focuses on the analysis of rainfall-runoff processes and erosion characteristics of selected catchment in different landscape management. This analysis was solved at the Lukavecký brook catchment, which is located in the Pelhřimov district in Vysočina region. The theoretical part of the thesis describes the rainfall-runoff process and then focuses more on individual processes. It also characterizes water erosion, its consequences, forms and erosion control. At the end of the theoretical part are described methods of calculation of water runoff and water erosion. The practical part describes the catchment of the Lukavecký brook, its characteristics of natural conditions and the threat of water erosion. Then there is a procedure for processing of bases and data in the program ArcGIS. Subsequently, it includes an assessment of the different measures and changes in the type of land to drain water from the catchment and erosion threat.
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