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Optimization of digital river network and its impact on catchment water management
Hošek, Zdeněk ; Matoušková, Milada (advisor) ; Šípek, Václav (referee)
Digital river network dataset is an important source of information in any aspect of water management decision making. It is also a base for modelling or scientific research in many different fields. Development of the dataset in the Czech Republic had been fragmented in a past and as a result three different datasets have been developed that cover the whole of the state's territory. The datasets contain different geometries, different and often conflicting attributes and serve different purposes. Today the time has come that water management decision makers have realised that the situation is no longer sustainable and make effort to merge the datasets into one. The task brings in several technical issues and a potential for severe legal consequences. The aim of this study is to develop a methodological approach to merging the existing datasets into one. This methodological approach to decision which of the conflicting or different attributes should be adopted is based on assumption that the existing datasets will be merged into one consisting the best of all. Comparison of features in the existing dataset will inevitably lead to many conflicts when it will be necessary to decide which of the considered features should be adopted to the resulting dataset. The study considers the main purposes which...
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The assessment of change in the water balance of Hačka catchment due to the climate change
Moravec, Vojtěch ; Hanel, Martin (advisor) ; Ladislav, Ladislav (referee)
In the presented paper the changes in mean runoff, temperature and precipitation totals in
an observed period 1962-2015 in the catchment river Hačka are assessed. The paper further
presents the analysis of climate change impact on mean runoff between the periods 1984-2014
(control period) and 2035-2065 and 2068-2098 (scenario periods) using the projections of three
regional climate model simulations. Thin Plate Spline interpolation was used to estimate basin
precipitation and temperature. Modified hydrological analogy was used for precise quantification
of naturalized runoff (i.e. not affected by water use). Climate change scenarios were
derived using simple delta change approach, i.e. observed series of precipitation and temperature
were adjusted in order to give the same changes between the control and scenario period
as regional climate model simulations. Hydrological balance was modelled with a conceptual
hydrological model Bilan. The parameters of the hydrological model were estimated using observed
data. These parameters were subsequently used to derive discharge series under climate
change conditions for each regional climate model simulation. Results showed a 1.7 °C average
increase in mean annual temperature in the scenario period 2035-2065 and a 2.8 °C average
increase in the scenario period 2068-2098. The seasonal cycle of precipitation in the scenario
conditions is shifted, although mean annual precipitation totals remain practically unchanged
(max changes -8.1 %; +9.3 %). The mean annual discharge decreases by 5.7% in average (most
20.3 %) in period 2035-2065 and a significant decrease of 25.5% in average (most 45.9 %) in
annual mean discharge is expected in the period 2068-2098. Frequency of minimal runoff is expected
to increase up to two times. Precipitation increase is expected from the beginning of the
fall to the beginning of the summer, with a slight decrease in spring. Increase in precipitation
is followed by evapotranspiration increase, caused by increase in temperature. Summer precipitation
is expected to decrease as well as summer runoff. Due to the temperature increase, time
shift of the snowmelt is expected from the periods between March-April to January-February.
This will also affect the increase of the discharge in this period. This knowledge can be applied
in water management planning in the future.
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Factors affecting the water discharge from the river basin during rainfall-runoff events
TICHÁČEK, Pavel
This thesis focuses on the factors affecting runoff water from the basin during the rainfall-runoff events. Work begins by describing the circulation of water in nature and continues with hydrological balance. Next chapter is the formation of precipitation and water runoff, in which the water outflow is divided into surface and subsurface. In the work is characterized runoff process and there are described factors that affect water runoff from the watershed. The last part describes the possibility of using these factors for creating erosion and flood control.
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Factors affecting the total outoff from the watershed and its individual components
MORAVCOVÁ, Lenka
This thesis is focused on the topic of total outflow from the watershed. In the first part water is divided into surface water, subsurface and groundwater, there is also described water circulation, hydrological balance, water retention and water accumulation, as well as characteristics of hydrographic network in the country. There are listed and explained outflow folders and measures to reduce surface runoff. In the second part of this work methods of separating the individual components of outflow, such as CN-method, Kliner and Kněžek method, model SMODERP, HYDROG model, GROUND and MGPM methods are described. In the conclusion it is explained that outflow from the watershed generates not only because of rainfall, but also due to geological, pedological, anthropogenic and other factors.
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Base flow-separation method, factors affecting the incidence and size
VLASÁK, Ivo
This bachelor thesis focuses on hydrological cycle, hydrological balance and hydrology of underground waters. Underground waters holding in a river stream is one of the most important characteristics of hydrological mode of a river. Underground waters proportion is detected from a line of flow rate in the course of many years via so called separation of underground river stream. There are several methods of separation and problematics of these methods is described in detail in this thesis. What is mentioned further are the factors influencing occurance and size of an elemental outflow rate, these factors being in particular climate, geology,relief of land, vegetation and last but not least human aktivity. Outflow rate which comes through the cycle of underground waters can be considered as an elemental outflow rate. Outflow rate is a subject matter of a further chapter. Water flowing out in a form of an elemental outflow rate creates both surface and underground waters, which are constituents of a cycle of water in the nature, which is described in this thesis in a detail together with surface, underground and subsurface water.
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Analysis of factors affecting a direct runoff from the catchment area
NEUBAUEROVÁ, Andrea
This diploma thesis follows my bachelor thesis. The main purpose of the bachelor thesis was to clarify fundamental terms and to explain the sorting of particular parts of a direct flow that involves both the surface saturated flow and the hypodermic flow. This diploma thesis is focusing on the origin of direct flow in a river basin. Specifically, it deals with river sub-basin P6, P52, and P53, which are located in Kopaninský potok river basin. Furthermore, it deals with Jenín I. and II. river basins and the last analysed is Ostřice river basin (SO2). Factors influencing direct flow are researched on all river basins. It is impossible to say that the origin of direct flow is caused solely by a single factor; it is always the result of multiple factors. Among these factors belongs the atmospheric precipitation, type of soil, vegetation, climatic and anthrophogenic conditions, land use, and inclination of the area. The bachelor thesis explains the issues of multiple methods of flow separation, but this diploma thesis is primarily focused on two methods for calculation of ratio between the direct and the total flow. 1) Empirical method GROUND, which is used to separate hydrographs of medium daily river basin flow. 2) Method of digital filter by Lyne Hollick separate fast and slowcomponents from the overall concentrated flow and are based on the theory od signal analysis. Afterwards, the results of flow separation were compared to the factors influencing the origin of the direct flow. The daily total flow rates for every analysed river basin were used as the input data for calculating the flow separation.
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The influence of drainage systems on catchment water regime
ČERVONYJ, Jakub
The influence of drainage systems on catchment water regime was dealt within this bachelor´s work in the form of literature review. The water regime of landscape as well as components of hydrological balance in catchment was described in the first part. Basic concepts of agricultural drainage systems are described in the second part. The last part of literature review was devoted to the influence of drainage systems on water the characteristics of Jenínský strem catchment, where the systematic drinage systems were built in history. The description of the area of interest includes the evaluation of functionality of drains after 30 years of presence in the catchment, executed by field research.
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Direct run-off - formation and separation methods
NEUBAUEROVÁ, Andrea
The bachelor´s thesis occupies with an issue of a direct flow. The main purpose is the explanation of the basic terms of the issue and the explanation of the sorting of particular parts of a direct flow, that involves a surface saturated flow and a hypodermic flow. Subsequently the thesis describes its participation in the hydrogeological cycle, which means the participation in the permanent circulation of a surface and underground water on Earth. The extreme precipitations are dangerous due to their force, total sum and intensity. The inception of hydrological occurrences like floods or dry seasons is possible owing to this. The fallen precipitations have a big influence on a surface flow and a transportation of soil particles. The thesis is focused on the inception and the genesis of a direct flow. Further it focuses on the factors that influence the flow. Among these factors belong climatic and anthrophogenic conditions, vegetation, type of soil and atmospheric precipitations. There are clarified selected methods of potential separation which are explained and described in detail. This part of the issue mentions CN curve method, GROUNG method, MPGM, analysis of dropped subdivisions and finally method of digital filter (Chapman). These methods divides the flow on an elemental flow and direct flow.
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Methods of the separation of the base flow and trends of nitrogen concentrations in this base flow
MAIEROVÁ, Monika
This Bachelor thesis is aimed to clarify the hydrological cycle, hydrological balance, groundwater hydrology, the selected basic baseflow separation methods of comparing them and last but not least, nitrogen cycle, nitrogen, nitrates, ammonia nitrogen and nitrogen in groundwater. In the work there is also closely analyzed the total, surface and subsurface outflow and the detailed division. The methods of the groundwater baseflow separation are described with regard to content of nitrogen compounds., which currently create the most common type of pollution of groundwater used as drinking sources.
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