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Hodnocení vlhkosti půdy na stanovištích protierozních opatření s výsadbami dřevin v kontextu intenzivně obhospodařované krajiny
Slezák, Vojtěch
Grassy linear elements with tree planting are an effective tool for reducing the erosion risk of agricultural land on sloping arable land. The research on the deve-lopment of soil moisture during one vegetation season in intensively productive areas on transects of arable land above anti-erosion measures, below anti-erosion measures, and anti-erosion measures themselves was conducted as part of this thesis. Soil moisture was measured in 14day intervals using Electric impedance spectrometry (EIS) from March to October. Soil analyses were also carried out at the study sites. The research results showed that lower soil moisture occurred at the site with anti-erosion measures compared to sites with arable land after the main crop was harvested. These results suggest that the main factor moderating soil moisture between study sites was plant water transpiration. Furthermore, it can be inferred from the results, assuming other research, that anti-erosion measures have a higher infiltration capacity due to preferential water flow pathways.
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Environmental assessment of the Czech Republic based on Water Footprint
Žlábková, Jana ; Hák, Tomáš (advisor) ; Vačkář, David (referee)
This dissertation sets its goal in application of the water footprint indicator, which is a practical and multi-layered indicator of water sources consumption. Of human activities, agriculture presents the most significant demands on water sources consumption. Therefore I have turned my focus to the widely-discussed issue of biofuels production, because the input materials for production of this kind of energy are agricultural crops (in the Czech republic those are: oilseed rape, sugar beet, Indian corn and winter wheat). The calculated results of water footprints of the selected industrial crops (m3 /t) and of water footprints of the heating value units of that crops (m3 /GJ) offer us a concrete notion of energy requirements of water of that chosen industrial crops in the conditions of the Czech republic. Keywords: water footprint indicator, biofuels, oilseed rape, water consumption, biodiesel, bioethanol, evapotranspiration.
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The influence of evapotranspiration on the groundwater of floodplain forests: Libický luh
Vašková, Hana ; Weiss, Tomáš (advisor) ; Slavík, Martin (referee)
The recherche part of this bachelor thesis deals with evapotranspiration from floodplain forests and its influence on the depth of the groundwater level and mineralization of groundwater. As floodplain forests in the Czech Republic are represented only in smaller fragments, there is a mention of the effect of mineralization on plants. The thesis describes the principle and use of stable isotopes in hydrogeology and the comprehensive characteristics of the area of interest of the experimental part, the Libický luh National Nature Reserve. The experimental part includes the observation of the level, conductivity, temperature, pH, and determination of the isotopic composition of the underground and surface water in Libický luh, where high mineralization of the groundwater was previously detected. The thesis discusses the effect of evapotranspiration on the content of dissolved substances in the water in Libický luh as a possible cause of this phenomenon. It was found that as the temperature rises, the groundwater level drops, and that mineralization remains relatively constant throughout the year. The drop in the groundwater level is evidently caused by intensive evapotranspiration from the floodplain forest during the growing season. However, longer time series of conductivity or hydrochemical...
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Evapotranspiration of peat soils
Urbánková, Karolína ; Weiss, Tomáš (advisor) ; Šípek, Václav (referee)
The correct determination of evapotranspiration is critical for the calculation of the water balance. Although research on evapotranspiration in general is already quite advanced, peat soils are so specific that they may require their own unique approach. Hydrologists have a series of calculations and models to determine evapotranspiration, but these are not always sufficiently accurate, especially at higher temperatures. The aim of this thesis was to summarise the existing knowledge of evapotranspiration in peat soils and to determine whether the peat layer thickness has an effect on peat evaporation. The thesis presents a survey of methods for determining evapotranspiration that can be applied to peat soils. The laboratory experiment used a split container, one part of which contained peat and the other part had peat only in the top 7 cm, with quartz sand underneath. The two parts were joined at the bottom with gravel and thus permeable to water. The trend of water loss, soil water potential and soil moisture was monitored. Preliminary results show that peat strength has a clear effect on evaporation. Further research would, among other things, look for a specific height of the peat layer for which the underlying material would no longer have an effect. Key words: evapotranspiration, peat,...
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Analýza energetické bilance intravilánu města pomocí metod dálkového průzkumu Země
ŠOUREK, David
The energy balance of each urban area depends on the specifics of active surface and other complex phenomena. In general, compared to the surrounding rural landscape, dry and impermeable surfaces predominate in urban areas. Different types of built-up areas have various properties determining how distributed solar radiation is. Overall, it is through energy fluxes defined by the sensible heat flux, the latent heat flux of evaporation, and the soil heat flux. Besides, vegetation plays a significant role in the proportions of fluxes. Plants can effectively transform the obtained solar radiation and thus influence the microclimatic situation through the cooling effect of evapotranspiration or other ecosystem services. Nevertheless, the efficiency depends on the state of vegetation and other prevailing conditions (weather, etc.). As the study area was selected the town of Písek. The research took place on two summer and two autumn days using remote sensing and statistical evaluation. The results showed the growing dependence of the latent heat flux of evaporation in localities with a higher vegetation density and a sufficient water supply. High values of surface temperature and sensible heat flux occurred in built-up areas with predominant materials with a large specific heat capacity, i.e. concrete, asphalt, sheet metal, stone etc. These indicators thus defined some problematic types of built-up areas, especially in terms of surface overheating or of the occurrence of local heat islands. Specifically, it was the historic centre, industrial zones and shopping centres. A better microclimatic situation prevailed in the park with a water surface, suburbs and built-up areas of family houses.
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Proposal of project based education on the topic of air-conditioning function of vegetation in the landscape
ŽEJDL, Matěj
As part of this work, the role of the regional vegetation in the water cycle was designed in the project of education. The project was made in a try of the praxis. A part of the education is measuring air temperature and the relative air humidity in the different habitats. Due to this measuring primary school students can see differences between habitats and they can think about the meaning of the project education in the role of the differences in the vegetation and in which way flora is influencing the water. The work is focused on the research of the meteorological and biological conditions suitable for education project management. Work also briefly sums the role of respondents in the Biology lessons and their knowledge of the examined topics made during the lectures. The finding of the primary school student's knowledge was done with the use of questionnaire.
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The role of vegetation in the solar energy distribution and the water cycle in the landscape - an impact of inquiry based education on pupils understanding
BRČÁKOVÁ, Tereza
This article brings the results of the survey aimed on the impact of inquiry based education on the students' knowledge of the role of vegetation in the solar energy distribution and the water cycle in the landscape, which was realized at four schools. The introduction presented the issue of the role of vegetation in the solar energy distribution and the water cycle in the landscape. Further, the bachelor thesis presents problems of inquiry based education, and also implementation of inquiry based science education on this theme in elementary schools education and grammar schools education relating to didactic textbooks. The outcome of the thesis brings the results of the survey made by pretest and posttest forms. From the data collected follows that inquiry based education increases the pupils' knowledge of this topic. Knowledge regarding distribution solar energy by plants is important for understanding water cycle in landscape and evidence based water economy, which can reduce losses of water in a local measure and mitigate subsequent drought.
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Soil evaporation and its controlling factors
Fröhlich, Lukáš ; Slavík, Martin (advisor) ; Mareš, Jakub (referee)
Evaporation is one of the basic members of water cycle, affecting a wide range of natural processes. The importance of the study of evaporation is even greater under conditions of climate change. This bachelor thesis focuses on soil evaporation and its controlling factors. The way in which water moves in porous media is described, and the terms evaporation, transpiration and evapotranspiration are defined. The division of the soil evaporation process into three phases is described and relative evaporation rates characteristic for the different phases are summarized. The relationship between evaporation and the spatial distribution of moisture inside soil is explained. The influence of internal and external factors on the evaporation rate is then described. It is assessed whether these factors contribute to higher or lower evaporation rates and under which conditions this occurs. It is evaluated whether the degree of influence of these factors is constant or whether it varies according to the circumstances and the evaporation phase in which the factors operate. Key words: evaporation, transpiration, evapotranspiration, evaporation phases, flow of underground water, external and internal factors of evaporation
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Approaches to estimate wetland evapotranspiration and the evapotranspiration loss of groundwater from wetlands in the Liběchovka and Pšovka catchments
Pátek, Karel ; Bruthans, Jiří (advisor) ; Slavík, Martin (referee)
This work is dedicated to the study of evapotranspiration in wetlands. The theoretical part is an overview of methods that are used for estimation of evapotranspiration, especially in the wetland environment. The practical part is focused on measurement of evapotranspiration in the wetlands located in the upper part of the Pšovka and Liběchovka river watersheds. Periodical fluctuations of water table and water flow in the stream were observed there due to evapotranspiration. The role of evapotranspiration was dependent on the mean daily temperature and sunshine duration. For the warm sunny days the fluctuations indicated that in the studied wetland the maximal daily evapotranspiration can cause 32 % decrease of water flow in the stream. The evapotranspiration derived from stream flow oscilation reached 86 % of potential evapotranspiration based on Oudin method. Potential evapotranspiration in the Liběchovka wetlands in summer is capable to decrease the discharge of Liběchovka in similar way as groundwater abstraction.
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Water Balance Hydrological Models Method Comparison
Štolfa, Filip ; Bednář, Martin (referee) ; Marton, Daniel (advisor)
In this work, two types of lumped balance precipitation-runoff models were compiled, from which the model taken from the Sicilian regional climate model was subsequently modified and these modifications were compared with other models. The practical application was carried out in the Svratka river basin above the Vír reservoir ending in the final profile of Dalečín. The input data from this river basin were precipitation totals, average temperatures and flows in the final profile, from which the calculation was subsequently performed in a monthly step. The individual models were compiled in two variants differing in the length of the time series and the number of regression coefficients. All assembled models were subsequently calibrated using four calibration criteria, for which the effectiveness was verified during validation by one common criterion. At the end of the work, individual models and calibration criteria are compared.
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