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Effect of selected physical-geographical factors on the snow accumulation and snow melt
Pevná, Hana ; Jeníček, Michal (advisor) ; Langhammer, Jakub (referee)
Effect of selected physical-geographical factors on the snow accumulation and snow melt Abstract: This master thesis analyzes the influence of physical-geographical factors on spatial distribution of snow water equivalent, and its evolution. In this work, emphasis is placed on describing the influence of vegetation, aspect and altitude. Measurement was carried out in experimental catchments Zlatý Brook and Bystřice River in western part of the Ore Mountains in winters 2008/2009, 2009/2010, 2010/2011 and 2011/2012. To evaluate the influence of these factors on value of snow water equivalent there was used one of the methods of multivariate statistical analysis - cluster analysis. The research shows that the greatest influence on the distribution and evolution of snow water equivalent in the experimental basins has vegetation and some dependency was proved also between the points of southern exposure. The measurement results demonstrate the suitability of cluster analysis for analyzing the data of point values of snow water equivalent. On the other hand the results showed the main limits of this method, especially the need for a large number of points with different characteristics. The results of measurements and statistical analysis are compared with results published in technical literature. Keywords: snow...
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Hydromorphological survey of the Bilina River
Kyselka, Jan ; Matoušková, Milada (advisor) ; Langhammer, Jakub (referee)
The main aim of this thesis is assessment and presentation of results of the hydromorphological survey of the Bílina river, which belongs to rivers with the biggest anthropogenic impact in the Czech Republic. The method Hydroecological monitoring (HEM, Langhammer, 2007) was used for the survey. This method is compatible with the Water Framework Directive 2000/60/EC. 53 parts of the river with the lenght 31,99 km were assessed. The thesis also includes assessement of the rainoff regime and information about protection of water ecosystems and sources in the Bílina river basin. Keywords: hydromorphology, HEM, Bílina river
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Water quality change in small watersheds after sewage water treatment plant building
Rödlová, Sylva ; Langhammer, Jakub (advisor) ; Kvítek, Tomáš (referee) ; Pechar, Libor (referee)
Změny kvality vody v malých tocích, vyvolané vybudováním čistírny odpadních vod, představují doposud málo studované a přitom velmi aktuální téma současné hydrologie. Tato studie se zabývá popsáním těchto změn a faktorů, které je ovlivňují. Pro účely výzkumu bylo vybráno pět malých, zemědělsky využívaných povodí prvního řádu (čtyři povodí průměrně 6 km2 , jedno 16 km2 ). V každém zájmovém území byla vždy jedna vesnice od 640 do 2 500 obyvatel. Během 7 - 16 let trvajícího měsíčního monitoringu základních indikátorů kvality vody (O2, BSK5, CHSKCr, TOC, konduktivita, N-NH4, N-NO2, N-NO3, PC, P-PO4) byla zachycena stavba čistíren v obcích. Spolu s daty o účinnosti čistíren byly vyhodnoceny změny kvality vody v toku. Identifikované typy změn ukazují na problematické aspekty vývoje kvality vody v malých povodích. Kromě očekávaného rychlého a razantního snížení hodnot zátěže po výstavbě čistírny odpadních vod se vyskytují i odlišné projevy změn - pouze mírné snížení zátěže, stagnace, dokonce i zvýšení koncentrací sledovaných indikátorů. Mezi další typické změny patří navýšení hodnot 1-2 roky před uvedením čistírny do provozu a opožděná nitrifikace v toku způsobená nevhodným provozem čistírny. Mezi nejdůležitější faktory ovlivňující změny patří provoz čistírny, velikost průtoku recipientu, zemědělské...
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Influence of spatial snow distribution on flood course
Kučerová, Dana ; Jeníček, Michal (advisor) ; Langhammer, Jakub (referee)
For the purpose of hydrological forecasting on mountains' and sub-mountains' rivers is important knowledge of distribution of snow water equivalent in the watershed. Submitted thesis therefore deals with comparison of 9 interpolation methods in terms of quality of their forecasting when predicting snow depth and snow water equivalent in watershed Bystřice (127,6 km2 ), which is situated in the northwest of Bohemia in the Ore mountains. Point data of snow depth and snow water equivalent used in interpolation were sampled during an off- road measuring in 17. 2. 2010 at the 14 snow sampling locations. The interpolation methods were: (1) Thiessen's polygons, (2) inverse distance weighting, (3) global polynomial (4) local polynomial (5) radial basis functions, (6) ordinary kriging, (7) cokriging, (8) residual kriging and (9) orographic interpolation. Independent variable-altitude used in the calculation of snow depth and snow water equivalent was used only in the last three listed methods. Predictive ability of interpolation methods was evaluated by using cross-validation and visual comparison of predicted maps. The best prediction ability was provided by residual kriging and orographic interpolation. The geostatistical methods were next in the order. The method of Thiessen's polygons and inverse distance...
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Impact of stream and floodplain modification on the flood effects.
Rettichová, Zuzana ; Langhammer, Jakub (advisor) ; Matoušková, Milada (referee)
The thesis deals with evaluation of the Volyňka river network modification on the basis of field survey, and identification of critical stream segments, which may influence course of flood events by means of GIS analysis. Two extreme floods took place in the Volyňka river basin in the years 2002 and 2009. The paper evaluates causes, course of events and effects of the floods. To get information about river network modification the HEM-F fiels survey methodology was used. The whole stream of Volyňka river was investigated from its spring to Volyně town, the tributaries in the upper part of the Volyňka river basin and the stream Spůlka. Intensity of stream modificatin and flood effects character were evaluated and critical sections were indentified on the basis of the mapping results. The potential flow obstacles are the most frequent type of critical modification of the stream. Especially the unsufficiently designed bridges, weirs and culverts cause the most intensive damage and geomophological effects of the flood. Individual kinds of obstacles are typical for certain sections of the river flow. Modifications limitating use of retention potential of the floodplain are often present in the central and lower parts of the Volyňka river basin. In several critical stream segments there were proposed...
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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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Analysis of flood events in the Upper Opava river source area
Lautnerová, Lucie ; Kliment, Zdeněk (advisor) ; Langhammer, Jakub (referee)
Present days are characterized by raising awareness of natural hazards, especially the risk of flood events. Extreme floods are connected with large - scale material damage and also endanger human lives. That's why the issue of flood formation and its possibility of forecasting has became disccused topic these days. Research of passed floods provides principles of effective flood protection in specific area. The main aim of this thesis is to analyse flood events that passed in the uper Opava river basin, concretely the source area containing the Černá, Střední and Bílá Opava river basins. This analysis refers about the flood frequency, different seasonal regime of floods occurence and looks for the relationship between atmospheric conditions and origin of flood events in the period of 1963 to 1997. Part of this thesis also summarizes main types of floods raised in the source area and compares different flood threat of the Černá, Střední and Bílá Opava rivers. There is also mentioned some basic differences of drainage formation, natural conditions and rainfall distribution in specific catchment area.
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High temporal satellite data assimilation for vegetation spectral characteristic assignment
Malíková, Lucie ; Langhammer, Jakub (referee) ; Štych, Přemysl (advisor)
The application of high temporal satellite image data for designation of the spectral characteristic of vegetation Abstract The objektive of this paper is to evaluate possibilities of high temporal satellite data assimilation for continuous monitoring of the spectral characteristic of vegetation. There is also given the suggestion of metodology for processing MERIS data and for continuous monitoring of spectral characteristic of landscape objects. Finally, vegetation cover database for the Czech Republic in the year 2009 is created from sectorial analysis. In the paper there is used the LSU classification and thresholding of vegetation indicies histograms. The universal decision algorithm for classification of vegetation landscape component are described and particular thresholding values for the year 2009 given. The finally product of this paper is Czech vegetation cover database for the year 2009 with overall accuracy of 63,35 %. Accuracy for forest is even over 80 %. Keywords: remote sensing, MERIS, vegetation, spectral reflectance, LSU, BEAM
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Modelling the course of extreme floods in the context of landscape changes and integrated flood protection
Jeníček, Michal ; Langhammer, Jakub (advisor) ; Zezulák, Jiří (referee) ; Szolgay, Ján (referee)
Introduction Floods mean a considerable hazard for mankind. Effective protection against their impact represents one of the basic hydrology and water management tasks. The conception of flood protection came tfuough development reflecting the progress in natural processes description, flood experiences and also improvement in technology possibilities enabling better computation of flood measures effectiveness. Cunently centralized flood protection concept is replaced with íntegrated flood protection concept (Langhammer et al., 2008b; Dumbrovský et al., 2006)' which gives the complex flood protection solution for the whole basin by means of smaller, close{o-natural measures, such as small retention reservoirs. land use change, suitable agrotechnical principles etc. The thesis can be divided into three main parts that form three main pillars ofintegrated flood protection. These pillars are represented by three case studies. First study was made in Blanice River basin. It computes flood extreme changes in condition of changing landscape. Results could lead to positive land cover change which could cause the flood peak decrease. Second study was made in Chomutovka River catchment (Ore Mts.). It quantifies dry retention reservoirs impact on the course of floods by different precipitation extremities. Third study...
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