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Legal aspects of water retention in the landscape
Houžvičková, Markéta ; Žákovská, Karolina (advisor) ; Sobotka, Michal (referee)
Legal aspects of water retention in the landscape Abstract This diploma thesis deals with the legal aspects of water retention in the landscape in response to the current problems associated with impaired landscape retention capacity such as drought, erosion or floods. The author first outlines the factual and legal context of the issue, which is followed by an analysis of conceptual, administrative-legal and economic instruments of the Czech legal order that can improve water retention capabilities of the landscape. The diploma thesis analyses the relevant instruments of the Water Act, Forest Act, Act on the protection of agricultural land or Act on protection of nature and landscape. Consequently, it deals with the role of land-use planning, land consolidation and environmental impact assessment for the issue. The thesis includes comprehensive evaluation of the relevant legal regulation in terms of its effectiveness and possible proposals de lege ferenda.
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Hydrological drought in headwater areas of the Ore Mountains
Vlach, Vojtěch ; Matoušková, Milada (advisor) ; Kliment, Zdeněk (referee)
Changes in the hydrological cycle are one of the expected impacts of climate change. Until recently, Central European mountain ranges have not been considered to be affected by water scarcity. Nevertheless, recent years have suggested an increasing risk of drought occurrence also in these regions, which have a major impact on the water supply to rivers that drain them. The master thesis deals with the evaluation of hydrological drought in the headwater areas of three catchments in the Ore Mountains for the period from 1967 to 2018. The main aim is to compare the of hydrological drought characteristics in the catchment areas of upper Svatava River, upper Rolava River and Načetínský brook based on available hydrological and climatic data. In connection with this, the work aims to detect the long-term trends of drought occurrence in selected basins. Furthermore, the emphasis is given on the evaluation of natural conditions, especially the historical and current land cover changes in the study catchments. The results point to a significant change in the seasonality of the occurrence of hydrological drought in the second half of the studied period, when the streamflow deficits concentrate between August and October. Furthermore, increasing trends in deficit volumes were found in the catchment areas of...
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Effect of cellulose ethers on properties of hydraulic lime
Skoupil, Jakub ; Rovnaníková, Pavla (referee) ; Vyšvařil, Martin (advisor)
This diploma thesis deals with the study of the influence of cellulose ethers on the properties of hydraulic lime mortars. The availability and price of cellulose ethers in the industrial market is very favorable, but we can´t meet with studies using cellulose ethers in building materials, where lime is used as a binder. Cellulose ethers are commonly used as thickening agents in cement-based materials. The purpose of this diploma thesis is to review if cellulose ethers are appropriate for use in hydraulic lime mortars, either as water retention agents that contribute by water retention to better hydration of hydraulic binder components or to affect the properties of mortar in the fresh state. The theoretical part is dedicated to cellulose ethers, especially their production and how they influence the properties of building materials. In the practical part, the thesis deals with the influence of the dose of five different types of cellulose ethers on the properties of hydraulic lime. The properties in the fresh state and the physical-mechanical properties of mortars were monitored over time.
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The importance of the radiation balance for water retention of the landscape
Kofroňová, Jitka
As part of the radiation balance, longwave radiation is one of the factors needed to estimate potential evapotranspiration (PET). Since the longwave radiation balance is rarely measured, many computational methods have been designed. In this study, we report on the difference between the observed longwave radiation balance and modelling results obtained using the two main procedures outlined in Manuals 24 and 56 of the FAO. The performance of these equations was evaluated in the warmer months (April to October) over eight years at the Liz experimental catchment in the Bohemian Forest (Czech Republic). The coefficients of both methods were also calibrated based on local conditions. Four commonly used methods were used to calculate the PET (Penman-Monteith, Pristley and Taylor, Kimberley-Penman, Thom and Oliver). The use of default coefficient values gave errors of 40 100 mm and 0 20 mm for the seasonal PET estimates for FAO56 and FAO24, respectively (the PET was usually overestimated). Parameter calibration decreased the FAO56 error to less than 20 mm per season (FAO24 remained unaffected by the calibration). The FAO56 approach with calibrated coefficients proved to be more suitable for estimation of the longwave radiation balance.
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Soil water retention in the landscape
Hřebejková, Barbora ; Šípek, Václav (advisor) ; Frouz, Jan (referee)
Water retention in the landscape is one the current topics in environmental protection. It is affected by a number of factors and is changing both in time and space. The goal of this thesis is to examine the long-term development of water retention in the landscape and to determine the influence of different types of vegetation on the soil moisture underneath. In the first part of my thesis I review different soil types with respect to their physical characteristics and interaction with water, and ways of measuring soil moisture. The aim of the thesis is the sum up the basic knowledge about soil and basics behaviour, mainly in the relation with soil moisture. There are introduced methods of soil moisture measurement with regard to their limits. In the second part I focus on analysis of selected studies covering the topic of water retention in the landscape. Due to the technical difficulty is only a few studies devoted to a long term measurement of soil water by direct methods and therefore are results mostly limited to evaluate soil water retention by hydropedological models. In the final part I discuss and evaluate the results of the aforementioned studies. Key words: water retention, soil moisture, evapotranspiration, soil hydrology, climate change
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The effect of artificial drainage and subsequent restoration on carbon stock and water retention in a watershed
Kešner, Michal ; Frouz, Jan (advisor) ; Kuráž, Michal (referee)
In the 1980s, the meadows around Senotín in southern Bohemia were drained by subsurface pipe drainage. After considerable drought in 1992, this area was subjected to extensive research. In 1995, a part of the drained area was revitalized. The drainage pipeline was interrupted by seven clay screens, over four of them country lanes and shallow depressions were built. The research of this site was realized after revitalization and focused on the water regime of the soil and on the physical, chemical and biological properties of the soil. This thesis describes the state of water regime, physical and chemical parameters of soil in undrained, drained and revitalized areas 20 years after revitalization and compares them with data from research performed in the past. The rainfall and runoff data was measured in the catchment area, and soil samples were collected in the regular network. Research has shown that between 1998 and 2014 there has been a reduction in river runoff. However, a more detailed data analysis has identified the vegetation transpiration as the main factor. There has been no increase in soil retention or soil moisture. None of the investigated soil parameters on the revitalized area (bulk density, carbon and nitrogen content, C:N ratio, pH, and conductivity of the aqueous extract) is...
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Interaction of groundwater and surface water under extreme hydrological conditions in the floodplain of the upper Lužnice river
Fialová, Petra ; Janský, Bohumír (advisor) ; Šobr, Miroslav (referee)
The object of this work is an analysis of the influence of extreme hydrological events (floods and droughts) in terms of interaction between groundwater and surface water in the river floodplain. The aim of this thesis is also the evaluation of the hydrological regime of the upper Lužnice basin and evidence of retention potential preserved natural floodplain. The selected objectives of the work were resolved on the basis of the values of groundwater levels and surface water in the area of interest. Based on data from underground wells and a digital terrain model, it was possible to create an image of the distribution of groundwater levels in river floodplains during selected hydrological situations. Data from surface flow was obtained from several habitats in the flow direction Lužnice. This has enabled graphically illustrate individual flood waves and characterize their size, speed and transformation after the passage of a preserved natural floodplain of Lužnice river. Carried out research has been confirmed retention capacity of the floodplain, which is most significant at flow rates slightly in excess of the flow capacity of the river bed. However, extreme floods or in periods with many culminations in a relatively short time leads to reduces water retention capability of the floodplain. In...
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Near natural flood protection measures in the landscape
Pergl, Michal ; Matoušková, Milada (advisor) ; Kujanová, Kateřina (referee)
Floods are dangerous natural phenomenon that can threaten human lives and cause damage to property. Near natural flood protection and water retention in the landscape is an appropriate combination of flood protection and improvement of the ecological value of the area. The most used near natural measures have been tested in practice by meta-analysis of articles available in electronic and printed form and through case studies. The case study focuses on the creation of an appropriate near natural flood protection measures in the middle part of the river basin of Berounka in the CHKO Křivoklátsko. The main finding of the meta-analysis is a substantial alteration of the height of the flood wave and the flow rate by natural measures for small and medium-sized floods and minimal at extreme hundred-year floods. Case study identifies areas supporting natural retention in the floodplain of the river Berounka. Retention area in the CHKO Křivoklátsko could have a positive influence on the effects of small and flash floods in the lower part of the river Berounka. Near natural flood protection measures in the Czech Republic are currently only at the beginning to become promoted. In the future, it could play an important role not only in terms of protection against floods, but even against the drought.
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Přirozená retence vody v krajině versus výstavba retenčních nádrží
SEDLÁČEK, Jan
This work is focused on natural water retention in landscape. There are described basic principles of water behaviour in soil, comparing of water retention in different types of land-use and anthropogenic influences including flood-protection and land-use changes. In the practicle part, there is described an experiment which focuses on comparing of retention potential of land-use changes in catchment of water dam Orlík with retention capacity of the dam. This work includes GIS analysis which focuses on areas of each type of land-use in the Orlík catchment.
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Added value of green roofs
Hrachovina, Vojtěch ; Žák,, Antonín (referee) ; Petříček, Tomáš (advisor)
Introduction is focused on analyze green roof like a part of buiding construction, when thesis assembly principles of right proposal green roof layers. Main part describes characteristic properties green roofs at global impact. We get some added values after comparison with classic roof types. Master thesis consists of survey of added values of green roofs in these categories: life cycle assessment, microclima, outdoor climate, water retention. End of thesis devote to psychological effect of green roofs include questionnare about relationship between czech society and green roofs.
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