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Mapping Survey of the locality Areal Metra company in Blansko - north part
Chaloupka, Roman ; Hovorka, Jiří (referee) ; Kuruc, Michal (advisor)
The diploma thesis deals with the creation of map bases in the northern part of the Metra areal in Blansko in the form of a thematic map in a scale 1:250. Descriptive information for each element has been added to the map. The thesis describes in detail the process of creating a measuring network, detailed survey, calculations, testing accuracy and creation of a thematic map including descriptive information.
Vertikální profil koncentrace a toku aerosolových částic nad ornou půdou
Zapletal, Miloš ; Hovorka, J. ; Hladík, J. ; Juráň, Stanislav
V současné době představuje imisní zátěž území a obyvatelstva pevnými/kapalnými nebo směsnými částicemi o velikosti 1 nm – 100 μm suspendovanými v atmosféře, neboli PM, jeden z největších problémů nejen v České republice, ale prakticky v celé Evropě. Vysoké koncentrace PM jsou spojeny s velkým množstvím zdravotních problémů. Mezi ně patří respirační poruchy a zvýšené riziko rakoviny plic a kůže (WHO, 2006). V ČR je dlouhodobá expozice PM důležitým faktorem zodpovědným za snížení kvality života obyvatel. Mezi nejzávažnější účinky, pokud jde o celkovou zdravotní zátěž, patří významné snížení průměrné délky života (WHO, 2006). Dopravní a průmyslové činnosti jsou obecně považovány za hlavní zdroj částic PM10. Existující informace o chemickém složení, velikostním rozložení, podílu sekundárních částic a depozičním toku částic na různé typy povrchů jsou doposud neúplné. Měření koncentrace aerosolu bylo provedeno v mnoha městech na úrovni ulic nebo pro hodnocení osobní expozice (Kaur et al., 2005; Longley et al., 2004). Byla provedena eddy kovariační měření emisního toku částic nad velkými městskými aglomeracemi (Dorsey et al., 2002; Järvi et al., 2009; Martin et al., 2009; Deventer et al., 2013). Přímé měření emisního toku částic eddy kovariační metodou poskytlo informaci o vzestupném proudění vzduchu a vertikální výměně částic nad některými městskými aglomeracemi (např. Manchesterem, Londýnem, Helsinkami). Popis měření toku částic eddy kovariační metodou z letadla je uveden v práci Buzoriuse et al. (2006). Méně informací existuje o emisním toku částic nad různými druhy zdrojů v různých výškách např. nad ornou půdou, povrchových uhelným dolem nebo lokálními topeništi.
Atmospheric deposition of nitrogen - application of stable isotopes
Hanzlová, Barbora ; Hůnová, Iva (advisor) ; Hovorka, Jan (referee)
Human impact on particular parts of ecosystems has become a highly discussed topic. Due to different isotopic values of nitrogen, it is possible to evaluate the extent to which human influences the natural nitrogen cycle, using isotope measurements. Stable isotope measurement has been used in various scientific disciplines around the world. This thesis summarizes the findings about atmospheric deposition and the subsequent use of stable nitrogen isotopes. The objective of this work was to gather the information about the use of stable isotopes in the study of the atmospheric deposition and how to make better use of the information obtained from the measurements. Based on the literature review, it has been found that, unlike other countries, nitrate substances such as NH3 and HNO3 are not measured in the Czech Republic, which distorts the data on the nitrogen produced. The use of stable isotopes is a convenient method of measuring both not yet quantified substances as well as already measured substances contributing to atmospheric deposition. The stable isotope measurement method represents an improvement for the overall estimation of atmospheric deposition to provide more realistic values compared to the current approach. Key words: atmospheric deposition, nitrogen, stable isotopes
Dynamics of vertical and horizontal profiles of atmospheric aerosol in planetary boundary layer
Esterlová, Jana ; Hovorka, Jan (advisor) ; Jančík, Petr (referee)
The boundary layer of the atmosphere is a layer of air with thickness about 1 km above the ground. Open-cast mining is one of activities that polutes the air in this layer. It generates particulate matter (PM) mostly in size of aerodynamic diameter 1 - 10 µm - coarse patricles. The companies that does the mining pays for their emissions due to the law. However, these emissions are not experimentraly measured, they are calculated from given equation consisting of factors like the size of mining area, etc. Some papers have shown significantly higher concentrations of Coarse particles (or PM10) in surroundings of the mine. Other papers have found out that the origin of these high concentrations didn't come from the mining activities but is caused due to the activities at the place of measuring or nearby. There aren't many papers that measure the PM concentrations in the air in the mining area. This thesis shows the results of airship measurements in the air layers of the open-cast mine and above them. The experimentral site was brown coal mine Bílina in the North of The Czech Republic in important mining area. The measurements took place in December 2017. For measuring the number and mass concentrations was used APS - Aerodynamic Particle Sizes Spektrometr by TSI which sorts out the data into...
Charakterisation of fungal aerosol in size segregated aerosol
Shamratova, Kseniia ; Hovorka, Jan (advisor) ; Kozáková, Jana (referee)
This bachelor thesis deals with the issue of bioaerosol, properties of airborne fungal spores, describes their significance, concentration, methods of spreading and influence on human health. This work provides information about sampling and detection methods of bioaeerosol. Was proved the suitability of using of the first step of the high volume cascade impactor (Hi-Vol) BGI-900 to collect biaerosol samples for subsequent scanning electron microscope (SEM) analysis. Using the optimized method, bioaerosol samples were isolated from the polyurethane foam, which is the impact substrate of the impactor. Bioaerosol samples were taken from 3 locations in the Czech Republic: Prague, Březno, Láz. During the SEM analysis of 15 bioaerosol samples, 605 SEM images were taken, on 340 of them were identified fungal spores. The smallest number of spores were found in Prague. Approximately the same amount of fungal spores was found in Březno and Láz. Fungal spores were identified into 9 genus, 1 family, and 1 species. The percentage of deformed spores in Prague was 48%, in Březno 23%, in Láz 25%. The greatest variability of spores was at the Březno and Láz localities. The most common fungal genus was the Cladosporium genus. No positive or negative correlation was observed between the number of fungi and the...
Spatio-temporal PM2.5 variability in village during winter.
Štědrá, Karolína ; Hovorka, Jan (advisor) ; Bendl, Jan (referee)
This thesis evaluates the spatial variability of PM2.5 concentrations during two winter months in the small village Lbín close to Teplice at the turn of the year 2017/2018. The PM2.5 concentrations were monitored through a dedicated monitoring network using a total of eight DustTrak laser nephelometers (Model 8520). Six DustTraks were located directly in the village in the valley, one of them was located on the hill above the valley and the last one was located approximately in the half of the hill. Using a network measurements, we tried to determine that the household heatings are the main sources of air pollution in the village. The basic meteorological parameters - wind speed and direction, temperature and air humidity were monitored together with PM2.5 concentrations. It was observed statistically significant difference between the measuring stations, which points to the unevenly distribution of pollution sources. The particle concentrations typically reach peak values in the morning and in the evening. The maximum peak values were 2607 μg·m-3 in December and 4347 μg·m-3 in January. The lowest maximum values were 223 μg·m-3 and 177 μg·m-3 for devices located above the village. An important factor contributing to the current situation was wind speed. If the wind speed was higher than 1,29 m·s-1...
Atmospheric deposition of nitrogen - application of stable isotopes
Hanzlová, Barbora ; Hůnová, Iva (advisor) ; Hovorka, Jan (referee)
Based on the literature review, the thesis summarizes the use of stable isotopes in the atmospheric deposition. According to the studies and empirical research, the origin and the extent of the pollution in the environment can be tracked down. Due to the different isotopic values, it is possible to evaluate the extent of human impact on the natural cycle of the ecosystem. Nitrogen can be found in all nature constituents where it gains different isotopic values. The objective of this work was to gather the information about the stable isotopes and to prove whether they are reliable indicators in determining the source of the nitrogen in the given area. By using the evaluated study, the difference in pollution within the coastal and continental areas in Central Europe was described. Keywords: atmospheric deposition, nitrogen cycle, stable nitrogen isotopes, fractionation

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