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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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Methodical Procedures for Assessing the Impact of Extreme Weather on Property Damage
Sedláček, Milan ; Adamec, Vladimír (referee) ; Rožnovský, Jaroslav (advisor)
This diploma thesis deals with the basic legal prerequisites to determining the amount of damage done to a real estate (building) in the legal framework of Slovak Republic. Its aim is to determine and quantify the property damage caused by extreme weather. It deals with climate problems as well as its indicators. This is accomplished through two different approaches - the analysis of actual damage done to the property for one, and secondly, the damage dealt to the building during its restoration into previous condition. The thesis aims to establish a methodological procedure for calculating all damages done to the property.
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Actions on bridges caused by the water flow and floating items
Řezník, Jindřich ; Duchan, David (referee) ; Špano, Miroslav (advisor)
The subject of this thesis is the enumeration and analysis methods applicable to the calculation of loads on bridges from water and water-borne objects. It involves a hydrodynamics loads, loads from captured debris and from impacts of the individual water-borne objects and their clusters. It includes an assessment of the current situation, the teoretical analysis and model calculations on the concrete bridge with the evaluation of usable methods.
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Measurement of Stream Flow Rate Using Salt Dilution Method
Burdych, Marek ; Ondovčin, Tomáš (advisor) ; Slavík, Martin (referee)
Tracer dilution method for measuring flow rate in surface streams is the main topic of the bachelor's thesis. The first part contains a summary of the most important flow measuring techniques for surface streams, including current meter, float method, FlowTracker, ADCP, volumetric method, and computing techniques based on channel cross-section data. Large part is dedicated to tracer dilution method. The findings of field measurements of flow made on the Lo- děnice River using the salt dilution approach are detailed in the second section. Five conductometers were used to measure the water conductivity at three di- fferent sites. Conductometry was performed simultaneously in two different distances from injection site. Throughout the experiment, a sixth conductome- ter recorded the background conductivity value as a standard. The predicted flow values are compared to those acquired from nearby hyd- rometric station of the Czech Hydrometeorological Institute (CHMI) and from observations made using Flowtracker. Diferences in measured flow rate were interpreted as tracer losses. These losses were estimated. Keywords: hydrology, surface water, water stream, tracer dilution, conducti- vity, tracer
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UAV remote sensing of hydrological processes and fluvial dynamics
Lendzioch, Theodora ; Langhammer, Jakub (advisor) ; Cramer, Michael (referee) ; Hais, Martin (referee)
UAV REMOTE SENSING OF HYDROLOGICAL PROCESSES AND FLUVIAL DYNAMICS THEODORA LENDZIOCH Abstract Using drones and machine or deep learning algorithms (ML or DL) for environmental monitoring offers several advantages over traditional methods, including gathering high spatial resolution data quickly and non-invasively, acquiring real-time data, and covering large and remote areas. This dissertation focuses on snow cover, river granulometry, river sustainability, river bathymetry, and peatland dynamics based on approaches of drone-based imagery that are critical for understanding fluvial processes in mid-mountain regions and their implications for streamflow patterns and ecosystem health. Measuring Snow Depth (SD) and vegetation characteristics like Leaf Area Index (LAI) accurately is essential for effectively predicting snow cover and snowpack persistence across study sites (papers I and III). A further aspect of the fluvial process mediator involves the reproducibility of drone data. This allows for seamless coverage of riverbeds and the determination of ideal parameters for sediment surface cover detection. This can be done through photo-sieving or DL technique, which can analyze Particle Size Distributions (PSDs) of an entire river point bar from top-view UAV images (as described in papers II and V)....
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Comparison of precipitation and discharges in relation to nitrate concentrations in the Jenínský stream catchment.
VRZÁK, Zbyněk
This work deals with comparison of precipitation and discharges in relation to nitrate concentrations in the Jenínský stream. The locality is situated on the east of town Vyšší Brod in the southern part of Bohemia. Since the 80`s this small catchment is research area and in the year 2004 The Faculty of Agriculture has continued in this research in Jenínský stream catchment. The backgrounds for this work are data of hydrological year 2006 which are gained from continuous measuring and scanning in small catchment Jenín. There is a recurrency to generalize the precipitation impact which induce changes of discharges on the closing device in small catchment.
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Surface and ground water of the Libický floodplain forest
Bašta Spinali, Izabela ; Weiss, Tomáš (advisor) ; Slavík, Martin (referee)
In the Quaternary, the area of the Libický floodplain forest was shaped mostly by the action of the Elbe river. The river generated a structure of oxbow lakes, pools, wetlands, floodplain forests or wet grasslands. These are connected by shallow groundwater of the Quaternary aquifer. During the Upper Cretaceous period, the area of Libický forest was flooded by the sea, which resulted in the formation of the bedrock of Libický forest - now the Cenomanian aquifer of the Poděbrady mineral spring structure. This aquifer is part of the Bohemian Cretaceous Basin. This thesis provides an overview about the waters in the area of the Libický forest, especially about: the development of the structures of surface water during the last ~2k years, groundwater of the quaternary aquifer and mineral water of the Poděbrady mineral spring structure. Finally, this thesis contextualizes this knowledge into climatic, geological, pedologic and also to ecological conditions of the area of Libický luh which is an important ecosystem in terms of biodiversity in otherwise relatively densely populated agricultural landscape. Key words: Libický luh, surface water, hydrology, Elbe, groundwater, hydrogeology, Cenomanian aquifer, Bohemian Cretaceous Basin, Poděbrady mineral spring structure, floodplain forest
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UAV photogrammetry as tool for evaluation of fluvio-morphological changes of streams
Lörinc, Michal ; Langhammer, Jakub (advisor) ; Hartvich, Filip (referee)
This thesis is focused on a use of a technology that is relatively new and popular in geoscience applications, including the fluvial dynamics research. Unmanned aerial vehicles are becoming widely used in numerous geographical subdisciplines due to their capabilities and advantages of UAV imaging in comparison with other remote sensing techniques. These advantages and also limitations together with general characterization of UAVs are summarized in the secondchapter of the thesis. The following theoretical chapters deal with basics of UAV photogrammetry and also evaluate the potential of UAV imaging in fluvial geomorphology. The fifth chapter of the thesis comprises a case study that evaluates the use of an UAV equipped with a non-metric camera for fluvial environment reconstruction. Images of Javoří potok have been processed in Agisoft PhotoScan and ArcGIS to indicate geomorphological changes of the stream channel that happened during a 5 month period from November 2014 to April 2015. Keywords: UAV; photogrammetry; fluvial geomorphology; hydrology; channel
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Analysis and modelling the changes of water quality in the Olšava river basin.
Kaiglová, Jana ; Langhammer, Jakub (advisor) ; Kliment, Zdeněk (referee)
The main goal of the thesis is to create an accurate model of the current state of water quality modelling in the river basin. The basin of the Olšava River, as found in the bachelor thesis "Analysis of Water Quality in the Basin", is polluted with large concentrations of total phosphorus PTot. The master thesis analyses sources of nutrients in the basin that is mainly listed in the vulnerable areas indentified under the Nitrates Directive 91/676/EEC, on the protection of waters against pollution caused by nitrates from agricultural sources. For the water resources management and environmental policy is crucial to recognize distribution of pollution sources throughout main categories. The thesis is concerned with the seasonal variability of the average mass concentrations along the river channel. Broadly used mathematical modelling software of water quality is discussed in the sense of reliability, availability and user interface. Last but not least is a suggestion of two improvements of the water quality based on the MIKE Basin modelling software. The main aim of these proposals is to be realistic in the economical and environmental sense. Proposals consider both in point and non-point sources. Key words: Mathematical modelling, MIKE Basin, Water Quality, Water Quality models, Hydrology, Olšava
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