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Application of mathematical models for simulation of hydrological conditions in selected streams
Kurková, Marie ; Vašků, Zdeněk (advisor) ; Michal, Michal (referee)
Flood is a natural phenomenon that occurs at different intensities and irregular time intervals. As to natural disasters, floods represent the greatest direct threat for the Czech Republic. They may cause serious critical situations during which not only extensive material damages are done, but may bring also losses of the lives of inhabitants in affected areas as well as vast devastation of cultural landscape including environmental damages. Important from the viewpoint of the elimination of potential threats and consequences of such events is the information issued by flood forecasting service about the character and size of flood areas for individual N-year flood discharges and specific flood scenarios. An adequate image of depths and flow rates in the longitudinal or cross profile of the watercourse during a flood event is provided by the hydrodynamic model. This is why the information obtained from the hydrodynamic models occupies a privileged position from the viewpoint of the protection of citizens' lives and mitigation of damage to their property. The first study is situated on the river Úhlava in meadows by Příchovice near the town Přeštice. The proposal of flood-protection measures is contained in Territorial control documentation. The documentation was elaborated on the basis of hydraulic calculations and experiences from the flood in August 2002. The mathematical model is practically used in the study of analysis of proposed flood-protection measures. The analysis is based on mathematical simulation of water outflow and water level on the river Úhlava. It is possible to use the non-commercial software Hec-Ras, version 3.1.1., for the simulation itself. One of the points of view of the possibility of using proposed flood-protection measures is total efficiency. The mathematical model is posssible to use as a basis of support for realization of proposed flood-protection measures on the river Úhlava in meadows by Příchovice within the grant programme "Program prevence před povodněmi II" under the control of the Ministry of Agriculture. In the second case the mathematical model is practically used in the study of hydrotechnical analysis of streams in cadastral unit. The analysis is based on matjematical simulation of water outflow and water level on chosen streams. It is possible to use the noncomercial software HEC-RAS for the own simulation. The analysis should be shown on dangerous places in the interest place. The mathematical model is possible of using to use as basis for revaluation of action in spatial plan or for view of the flood-protection measures in the village Mochtín. Basic input into the hydrodynamic models is represented by altimetry data. One of ways to obtain such data is through the method of aerial laser scanning (ALS) from the digital relief model (DRM). This method is considered one of the most accurate methods for obtaining altimetry data. Its bottleneck is however incapacity of recording terrain geometry under water surface due to the fact that laser beam is absorbed by water mass. The absence of geometric data on watercourse discharge area may perceptibly affect results of modelling, especially if a missing part of the channel represents a significant discharge area with its capacity. One of methods for eliminating the deficiency is a sufficient channel recess by means of software tools such as CroSolver. The third submitted paper deals with the construction of a hydrodynamic model using 5th generation DRM data, and compares outputs from this model at various discharges with a model based on the altimetry data modified by using the CroSolver tool. Outputs from the two hydrodynamic models are compared in HEC-RAS programme with the use of recessed data and with the use of unmodified DRM. The comparison is done on the sections of two watercourses with different terrain morphology and watercourse size. A complementary output is the comparison of inundation areas issuing from both model variants. Our results indicate that differences in the outputs are significant namely in the lower discharges (Q1, Q5) whereas for Q50 and Q100 the difference is negligible with a great role being played by morphology of the modelled area and by the watercourse size.
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Long-term changes of forest vegetation - the comparison of present species composition and biodiversity with the historical records
Vojík, Martin ; Boublík, Karel (advisor) ; Douda, Jan (referee)
The thesis presents the results of the research of the long term changes in semi-natural vegetation of lowland woodlands in the forest district Klínec (phytogeographical district Střední Povltaví, Central Bohemia, Czech Republic), which is located between the northeastern part of the Brdy Highlands (Hřebeny) and the Vltava River valley. Research of the long term changes over the past nearly 60 years was conducted by resampling vegetation on semi-permanent plots. Old relevés by V. Samek (1957), which were provided by the Czech National Phytosociological database, were used as reference data. Twenty-nine relevés were resampled, which were located using old data and GIS. The shift to shady plant communities (loss of heliophilous and expansion of shade-tolerant species) was found in the study area caused by higher canopy of tree and shrub layer due to the expansion of deciduous trees. Species richness (alpha diversity) was significantly declined. Homogenization of the vegetation was not significantly demonstrated in study area. Species of nutrient-rich habitats as well as alien and invasive species were expanded and fewer red list species of vascular plants was found. Vegetation change in the area was probably most affected by the change in forest management in lowland woodlands (decline of coppicing), eutrophication (deposition of nitrogen from the atmosphere, runoff from agricultural land) and the effect of forest animals especially wild boars.
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Heavy metals in Ohře river
Hrnko, Vladimír ; Vach, Marek (advisor) ; Heřmanovský, Martin (referee)
In this thesis, I dealt with the contamination of surface layers of river sediment in areas of Karlovy Vary and Sokolov selected elements and their comparison with data industry unencumbered by sediment from the area Písty and the limits of the International commission for the protection of the Elbe (MKOL).
The sediments were collected from monitored Ohře River Basin in the stretch Sokolov- Karlovy Vary, which runs through the industrial area of Karlovy Vary and Sokolov. In his thesis to prove whether the above flow influenced by industrial activities based on an evaluation of data from the samples. As a measure I chose indicators of heavy metal concentrations in surface sediments of the river flow. The samples were taken quarterly during the year at six sites. I chose three sites in Sokolov and three locations in Karlovy Vary. For comparison, one of the samples taken from the Karlovy Vary in the CHKO Slavkovský les, Svatošské skály. The monitored parameters are pH, Cd, Cr, Cu, Pb, Ni and Zn.
This locality is very ignored in these indicators and the results of my measurements can be an important basis for monitoring further developments in the river.
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Basic comparison winter wheat and neighboring flowering strip
Suchý, Viktor ; Kazda, Jan (advisor) ; Josef, Josef (referee)
Summary
The winter wheat belongs to the staple crop not only around the whole world, but also in the Czech Republic, where it has been grown on about 38 percent of the cultivated land and, regarding the general share of cereals, on 60 percent of the cultivated land. Since the cereals do not provide nectar, nor are they the valuable source of pollen, as regards to the diversity of insects the cereals provide rather poor environment. The lack of food resources for the living species of insects in the agricultural landscape influenced by the high ratio of cereals should be compensated by flowering strips. Regardless of the potential of the flowering strips to support the biodiversity of insects in landscapes, the flowering strips could boost useful species of insects in surrounding plants and help with pest control.
In 2014 the research experiment on a flowering nectar-rich biostrip supposedly improving the presence of pollinators as well as natural enemies was done on the field of the research station in Uhrineves, Prague. In autumn 2014 the winter wheat was sowed and then in spring 2015 the flowering strips consisting of 12 plant species were sowed along one side of the winter wheat field. The observations of the insect species presence were always conducted during favourable climatic conditions from the beginning of June until the harvest of winter wheat in late July. Insect captures were conducted using Moericke traps method once or twice a week and sweep-netting method once every two weeks. The number of insects species such as predators (Coccinellidae, Cantharidae, Staphylinidae), parasitoids (Hymenoptera parasitica) and pollinators (Syrphidae) were observed. Simultaneously, the intensity of flowering including species of weeds was assessed. The open flowers were counted on four unchanged spots on the field, the area of 1 square metre. MS Excel was used for data processing.
The hypothesis of the project has been confirmed. Using the sweepnetting methods, the higher number of monitored insect species has been found in the flowering strips compared to the wheat vegetation. Significantly higher number of parasitic wasps specimens has been observed. The sweepnetting method is considered as an appropriate in comparison to Moericke traps, which have been luring the insects in the vicinity, but have not proved the real presence of insects in the cover.
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Growth performance of common-sized planting stock and saplings after plantation on forest sites
Kaiser, Josef ; Kuneš, Ivan (advisor) ; Tužinský, Marek (referee)
The clear-cut area which is afforested in the Czech Republic is around 20 th. hectares large annually. In the last decades, we have observed frequent periods of the spring and late summer drought, which significantly negatively influence survival of the reglarly used transplants (RUT) however. Thus, it is necessary to search methods, which can decrease such losses. One possiblity how to solve this problém is to used containered transplants, the second one is the use of the plant material (PM) of bigger size (semi-large-sized=SLSPS and large-sized planted stock=LSPS). These larger plants are more resistant to unsuitable influences of environment than the RUT. The advantage of SLSPS and LSPS is also shorter time of necessary care to plants and lower costs to secure plants in comparison to RUT. Above mentioned facts were taken into consideration in creation of instructions for my bachelor thesis. The goal was to estimate the parameters of mortality and growth of selected various PM, moreover on sites heavily influenced by human activities. As model trees were selected: oak (Quercus robur) and lime (Tilia cordata). PM was generally bare-rooted (RUT, SLSPS and LSPS) and planting was done by mechanize equipment (into bored holes) at study sites Truba (Kostelec nad Černými lesy) and Hůrka (Planá nad Lužnicí). The first part of experiment was established at Truba on area of former forest nursery and cosisted of lime RUT and LSPS, the second one was established at site Hůrka in area of former sand querry, where RUT, and oak and lime SLSPS and LSPS were used. No one site was moved during experiments. The measurement on Truba was repeated on spring and on autumn 2012-15 and in 2015 on Hůrka. The height of PM was evaluated by using scale lath, the thickness of stem was measured above ground by using digital scale. Subsequently, data were evaluated in Excel and statistically tested by Kruskal-Wallis test. The results indicate, that mortality of RUT at Truba is 5 times larger than that of LSPS. The similar result was obtained also at Hůrka, the mortality of lime RUT was twice larger than in case of LSPS however. The lowest mortality was observed surprisely on SLSPS. The comparison of the oak RUT and LSPS indicated no any differences in mortality. The mortality of oak PM was generally significantly lover than lime PM one. Statistical tests also indicated, that the size of study sets of PM was too low for optimal scientific evaluation of selected parameters. The obtained results also indicate, that important factor, which influences mortality must be (apart from type of the PM) also additional, non-defined factors of environment up to now.
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Coupled transport processes
Jeřábek, Jakub ; Kuráž, Michal (advisor) ; Lukáš, Lukáš (referee)
The objective of this thesis was to implement a new module to the DRUtES model code, which allows to calculate coupled transport of moisture, temperature and miscible substance in a variably saturated porous media. The main part of the practical phase of the thesis was to implement appropriate constitutive relationships describing a coupled transport to the Galerkin finite elements scheme previously implemented in the DRUtES model. Besides this, a corresponding configuration files were made to assign parameters of the model into program data structures as well as a little bit of other programming work elsewhere in the code. Numerical solution of each transport equation was compared with its analytical solution. 1D moisture transport with the Philips semi-analytic solution of diffusive form of Richards equation. 2D temperature and miscible substance transport with an analytical solution of advection-dispersion equation. This comparisons suggested that the implementation was correct. The coupling of these processes was compared with a reference numerical solution. In this case was the fitness of results assessed in more qualitative manner with a literature. Before use of this coupled model to solve a real world problem, I would recommend to make a similar assessment with the real data.
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Czech agricultural policy and its impact on the management of selected agricultural entities
Straková, Alena ; Gebeltová, Zdeňka (advisor) ; Blanka, Blanka (referee)
The graduation thesis Czech Agricultural Policy and its Impact on the Management of Selected Agricultural Entities deals with the effect of the obtained grants in the selected agricultural enterprises in the time period of 2010 2014.
The enterprises are submitted to a financial analysis. Methods include the analysis of absolute indexes that shall evaluate the progress of the financial statement items by means of the horizontal analysis. Furthermore, the method of ratio index analysis is used where the liquidity, indebtedness, activity and profitability indexes are calculated.
Consequently, there is the analysis of the obtained grants and its impact on the enterprise economy. Juxtaposition of operating results of each subject including the operating grants and without them. The last step is the calculation of ratio indexes without the mentioned operating grants.
The conclusion evaluates the enterprise dependence on the grants on the basis of the analysis results and discloses the most prosperous enterprise within the group in view. Furthermore, there are measures proposed that could lead to improvement of the situation in enterprises. For example, to focus more on ordinary activities bringing revenues. Assess the size of rented land and its use within the business of enterprises or consider the appropriateness of financing foreign sources.
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Root system morphology of bare root and containerized beech and oak plants
Becher, Vladimír ; Kupka, Ivo (advisor) ; Bílek, Lukáš (referee)
The thesis follows the bachelor thesis on comparison of morphological and economic parameters of various types of seedlings, which resulted in the planting of containerized and bare root seedlings of the European beech (Fagus sylvativa Linne) and the English oak (Quercus robur Linnaeus) in a forest regeneration in September 2011 and April 2012.
The measurement of the height and thickness of the root neck of the seedlings was carried out on designated plots in March 2015. I also investigated possible mortality from the afforestation inspection in July 2012. Furthermore, 154 seedlings, 84 containerized seedlings a 70 bare root seedlings, in order to evalutate the development of the root system, its possible deformation and subsequently detection of the volume by using xylometric method. The data collected in the field were processed into tables and compared with the results observed in the bachelor thesis.
The average figures for the height, the thickness of the root neck and the volume of the root system showed almost identical development of bare root and containerized seedlings in the forest cover, even though the figures of individual seedlings were highly variable. When reviewing the development of the root system, I found unacceptable deformation of the main taproot at 25% containerized seedlings and 20% bare root seedlings. The remaining seedlings were without deformation or with acceptable deformation of the taproot (wavy taproot, unbalanced taproot with the axis in the above-ground part, an outgrowth).
It was discovered that containerized seedlings were more easily removable from the ground, the seedlings were not sufficiently fixed in the ground and its root system was in some cases less developed than it was with bare root seedlings. This may be influenced by several factors, e.g. the influence of richness of the root system on fine roots, the obstruction of development of the root system by cementing the surrounding soil when using the slit method.
The bare root seedlings, the English oak in particular, showed root development to a greater depth, which is very important not only for sealing but also as an important factor in the drought season and extreme summer temperatures when there is rapid exhaustion of the moisture in the upper horizon of the soil due to the vapor.
Unfortunately, it was not possible to verify these findings in a larger sample size, as there had been major damage of the forest.
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Changes in volume of water reservoir Fojtka due to sediment flux
Vlasák, Tomáš ; Moudrý, Vítězslav (advisor) ; Hradilek, Václav (referee)
Sedimentation in dams is a natural process depending on various factors over a period of time. Sediments influence both total capacity of dam's surface and also relief of bottom.
This thesis deals with amount of sediment in Fojtka dam and with change of its bottom's relief in past 109 years since its establishment. There was conducted measuring using an echosounder in a boat. Final output derived from this experiment was a point layer including 5500 point items. Subsequently there was executed a measurement of dam's shoreline using GPS device. Data were processed in ArcGIS software, then reduced and edited to be used for interpolation tools of ArcToolbox. In order to select the most accurate interpolation method, there were created validation data, which were compared with interpolated data. The best results have been achieved by interpolation method Kriging and TIN in resolution 0.5 m.
Original maps were vectorized for comparison with current condition. Created validation data were compared in order to show accuracy of particular interpolation. The most useful evaluated method for gained data was TIN method in resolution 0.5 m. TIN method was applied in both data sets for 2D and 3D bottom relief visualization and also for calculation of actual water volume and area of water surface of the dam.
Difference in bottom's relief of Fojtka dam showed capacity reduction about 6,7 % and reduction of water surface area about 3,2 %. Regular extracting of sediment in reservoir located above the dam causes this relatively small silting ratio.
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Landscape development and landscape values of a selected area in a specified relief type
Učňová, Klára ; Halamová, Jana (advisor) ; Lucie, Lucie (referee)
The submitted thesis deals with landscape analyzing and permanent landscape structures
evolution in chosen area with respect to land relief. Also with documentation and evaluation of
landscape values (such as medieval field patterns, scattered vegetation, viewpoints, relief, etc.)
and last but not least with suggestion of recommendations for future development, including
proposal of new development, specific for chosen area.
The theoretical part consists of summary of current status. Mainly the elements
characterizing landscape of the Czech Republic are defined here. The thesis also describes
history of Czech landscape since the Neolithic period and also evolution of medieval field
patterns. The landscape aesthetics and its influence to humans from emotional and content point
of view is mentioned in the theoretical part as well. In the next chapter there is an evaluation of
maps and description of possibilities of their usability for evaluation of landscape evolution.
The practical part is about project itself. At first the suitable area based on maps from 1 952
was chosen and their comparison with present state. By maps vectorization (both historical and
present one) supported by personal exploration, two map underlays were created. Based on
them, the statistical data for evaluation and comparison of land use categories evolution were
created. Also the analysis of appearance of given land use categories was performed.
Comparison of changes in evolution of balks is the part of the project as well.. One of this thesis
purposes was also evaluation of landscape directly on the spot. Based on this evaluation and
personal feelings from the area, design for better land usability was created. This design was
also economically considered.
In discussion at the end of the thesis was determined that epoch around year 1952 was a
breakthrough for landscape evolution. After this year, there was a huge decrease of ploughland
area. This decrease was replaced by permanent grassland and forests. In the end there is an
estimation about medieval field patterns important for landscape in chosen area and also
anywhere else.
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