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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Vliv půdní složky a rozdílného krajinného pokryvu na odtokový proces (experimentální výzkum v párových povodích Zbytiny) / Influence of soil matter and different land cover on the runoff process (experimental research in the paired catchments Zbytiny)

Královec, Václav January 2018 (has links)
The doctoral thesis deals with the evaluation of influences of causal factors that significantly affect runoff processes in landscape. The research is mainly focused on the examination of land and soil cover impacts and partially pays attention to the effects of surface drainage and snow cover. The main effort was to find out the extent of influences of each individual factor on runoff from a different type of landscape. In order to find the correct answer, a methodical approach was applied to small experimental paired catchments where the research has been continuously undergoing since the year of 2006 (the presented results have been collected for 11 years of observations). The small experimental paired catchments are located at the foothills of the Šumava Mountains and they represent small area neighbouring catchments of similar physical-geographic and hydrographic conditions. The catchments were selected as the comparative ones where the main differences are the landscape and soil cover. Moreover, the character of surface drainage is regarded to be an important variable. In the catchment area of the Zbytinský Brook, there predominates the grassland which is largely drained by the subsurface drainage system. In the catchment area of the Tetřívčí Brook the dominant cover is formed by the forest...
102

Vliv prostorového rozložení sněhu na průběh povodní / Influence of spatial snow distribution on flood course

Kučerová, Dana January 2010 (has links)
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...
103

Ztráty vody v povodí Loučenského potoka a Bouřlivce a možnosti jejich snížení v období hydrologického sucha / Water losses in the Loučenský brook and Bouřlivec basins and the possibilities of their reduction during the hydrological drought

Junková, Anna January 2021 (has links)
This thesis deals with the problem of water losses in the Loučenský brook and Bouřlivec basins. It was written on the basis of a project for the state enterprise Povodí Ohře, which dealt with the management of these streams. Loučenský potok and Bouřlivec are the sources of water for the Všechlapy reservoir, which provides a number of functions in the reservoir surroundings. However, the Všechlapy reservoir has been threatened by hydrological drought in recent years. For this reason, it is necessary to determine the water losses in the basin and focus on possible methods to ensure that the reservoir has sufficient water levels to maintain all of its major functions. In the first part of the thesis, the theoretical background related to the issue is explained. In the practical part of the thesis, water losses in the basin are detected mainly on the basis of longitudinal profiling of flows and recorded water withdrawals. Flow measurements were carried out on a total of 43 profiles in five different hydrological conditions with a focus on the dry season. The results show that there is a need to look for reserves in two areas. Firstly, in the management of the ponds, where it appears that a significant amount of water is being lost throughout the basins, and secondly, in the small-scale users who draw...
104

Návrh parametrů malé vodní nádrže v prostředí GIS / The proposal parameters of the small water reservoir in GIS environment.

Feltl, Jakub January 2012 (has links)
This report deals with rainfall-runoff modeling and small water reservoir projection with usage of modern software equipments (GIS, HEC-HMS), using maximum number of available data sources (BPEJ, LPIS, N-year rainfall gages, 3D contours …). The advantage of this method is that it is possible to predict the shape of hydrograph and flood wave volume as well. Other methods cannot offer judgment of flood wave volume and hydrograph shape as this method does. The most important thing in small water reservoir projection is the flood wave volume value, which is undervalued nowadays using wrong evaluation. This method’s advantage is variability of scenarios depending on soil surface, used agricultures, hydraulic and hydrologic parameters etc.
105

Využití vybraných metod umělé inteligence pro nalezení malých povodí nejvíce ohrožených povodněmi z přívalových dešťů / Use of selected artificial intelligence methods for finding small watersheds most at risk of flash floods

Ježík, Pavel January 2016 (has links)
In our region, heavy rains may occur virtually everywhere. Nowadays there are instruments to predict these events in sufficient advance, but without precise localisation, which is a problem. Present instruments for searching endangered watersheds are focused on operative evaluation of meteorological situation and actual precipitation forecast processing (nowcasting). The thesis brings quite different approach. Potentially endangered areas are detected with evaluation of long-term statistical variables (N-year discharges and rain characteristics) and properties of specific watershed. The whole issue is handled out of situation of actual danger, this attitude is so called off-line solution. The thesis describes a model based on selected artificial intelligence methods. The model forms the core of final map application. The use of model and final application is supposed to be used in area of preventive flood protection, and related investment decision-making. The model focuses on heavy rains and flash floods.
106

Analýza nákladové efektivnosti opatření vedoucích k snížení eutrofizace vodní nádrže Orlík / Cost effectiveness analysis of measures leading to the reduction of eutrophication in the catchment of the Orlik Reservoir

Macháč, Jan January 2013 (has links)
The growing demand for clean water has led to the adoption of the EU Water Framework Directive (Directive 2000/60 EC). New legislation has a major impact on the water management and the national economy and provides numerous requirements, including "good status" of all water bodies. The Framework Directive also implies the need for an economic analysis of the optimal process to achieve good status by using the cost-effectiveness analysis (CEA). The application of this method in water management is struggling with a number of methodological complications. One of the affected areas in the Czech Republic is the catchment of the Orlik Reservoir that faces excessive eutrophication. Eutrophication is caused by excessive introduction of phosphorus. The main sources of phosphorus are municipal wastewater, aquaculture and agriculture. As illustrated by professional research mentioned in this work and the actual processing of CEA of the catchment of the Orlik Reservoir, a wide range of methodological problems can be avoided by using appropriate tools. This thesis also presents that achieving of good status of the catchment would require annual cost of CZK 602 million. The most significant cost bearers are according to the CEA fisheries and municipalities.
107

Minulost a současnost krajiny bývalé rybniční soustavy Opatovického kanálu / History and present state of the landscape of the former fish pond system in the drainage basin of the Opatovický kanál channel (Central and Eastern Bohemia)

Leglerová, Anna January 2019 (has links)
This work is focused on the dynamics of landscape change of fish pond system in Polabí region, specifically the drainage basin of the channel Opatovický kanál. Theoretical part provides information about origin, development and present state of fish pond system. Experimental part provides the mapping of ponds in five time periods covering the epoch between the 18th and the 21st century. Information about ponds in the 16th and the 17th century are provided as well but without pond areas. The reason for their absence is insufficiency of sources. Development of the area and quantity of ponds is discussed as well as land use and land cover change on the extinct pond areas. Finally, application of the fish pond development knowledge in landscape planning and revitalization are discussed based on the information gained by the mapping and research. Key words: fish pond systems, land cover, land use, landscape changes, Polabí region, drainage basin of the channel Opatovický kanál
108

Hydronymie povodí horního toku Lužnice / Hydronymical Map of the Luznice River Basin

HAVRDA, Michal January 2018 (has links)
The main goal of our thesis is a lexicographic processing of names of watercourses in the Upper Lužnice (Ober Lainsitz) river basin. Due to its location on the borders of Czech and German speaking territories and gaps in Czech methodological approaches our thesis is based on sophisticated theories of German hydronomastics that reflect common etymological roots of European water names as well as of the Slovak ones that strive for modern international processing of hydronyms complying with uniformed, obligatory methodology of the lexicographic project Hydronymia Europaea. Water names that were excerpted mainly from archival and contemporary maps have undertaken semantic classification invented by V. Šmilauer and M. Frydrich regardless of the source language. Along with the verification of suitability of the foreign methodology adopted for Czech hydronyms the thesis makes partial advice on its innovation that could help make the using of the lexicon more user friendly.
109

Floristický průzkum povodí Pozdeňského a Bílichovského potoka na Slánsku / Floristic research in the basin of Pozdeňský and Bilíchovský creeks of Slánsko

BERANOVÁ, Hana January 2008 (has links)
ANNOTATION Hana Beranová University of south Bohemia in České Budějovice {--} Faculty of education {--} department of biology Course: M7504 Teacher for grammar schools Fields of study: Teaching of biology, Teaching of chemistry Floristic research of catchment area of Pozdeň stream and Bílichov stream round Slaný Diploma thesis 2008 The study deals with a description of vegetation of catchment area of Bakov stream and Zlonice stream. In title of study are used the names Pozdeň stream and Bílichov stream, but it{\crq}s only local description. The search had been realised during the vegetation seasons of the years 2006 and 2007. There are characterised geological-petrographical, soil, climatic, hydrographic ratios and basic phytogeographical characteristics of this area in the form of a search. Selected genera of the observed plants are characterised and their incidence is figured in the schematic map of the area. There were found out 299 genera of plants, from which there are 48 stated in the Červený a černý seznam cévnatých rostlin České republiky (stav v roce 2000) (Procházka F. (ed.), 2001). There are described locations of important genera of plants. In discussion of the thesis are described factors, which influence the incidence of some genera of plants. In the annex there are attached schematic maps with places of occurence of the plant genera and photographic documentation. Head of the diploma thesis: Mgr. Rostislav Černý, CSc.
110

Řešení protierozní ochrany na vybraném modelovém povodí. / Solution of soil protection from erosion in researched catchment.

SMRČKA, Štěpán January 2008 (has links)
Annotation Erosion is a chronic problem in both agricultural and nonagricultural land. Its has an inconsiderable effect on overall stability of landscape. In the case of farming management on agricultural soils the risk of erosive processes increases severalfold. In foothill and mountain areas with dominance of slopes and hills the soil loss during higher maximum 24hrs N-rainfalls can reach up to several tons per hectare. This work deals with the evaluation of soil erosion vulnerability in selected catchment {--} Ostrice catchment {--} in the Lipno reservoir area. The CN method was used for calculations and following evaluation of soil loss.

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