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Ambient ozon impact on vegetation
Bystrianský, Martin ; Hůnová, Iva (advisor) ; Čabala, Radomír (referee)
Bystrianský: Ambient ozone impact on vegetation - Abstract Ambient ozone is present in the air all around the world. It is natural component of the atmosphere, due to anthropogenic emissions of ozone precursors its concentration rise. That is unlikely, because ozone is toxic. Ozone is formed as a part of photochemical smog from ozone precursors by photochemical reactions. As ozone precursors nitrogen oxides (NOx) and volatile organic compounds (VOC) are called. Their main source is car traffic. Danger of ozone lies in its reactivity. It oxidizes most of organic compounds, especially those containing double bonds. These are present in membrane lipids. Furthermore, ozone forms more reactive compounds than itself - active oxygen species (AOS), free radicals. Ozone effects negatively both human health and vegetation. Ozone disrupts structure of the cells, which for plants means destroy of leaves and needles, photosynthesis disruption and biomass loss. For that, plants have antioxidants system for AOS scavenging. But it has little effect, when concentration of ozone is high during smog period. Therefore, limits for maximal concentration of ozone in the ambient air are set.
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Smoking and smoking habits in elementary school children
Pochmanová, Petra ; Braniš, Martin (advisor) ; Hůnová, Iva (referee)
According to WHO a smoking of cigarettes and other tobacco products is the second most common cause of dead worldwide and the fourth most widespread risk factor causing life threatening diseases. Smoking has also certain social impact. While in the nineteenth century and at the beginning of twentieth century it was considered to be some kind of characteristic for a specific social level. At fall of twentieth century harmfulness of smoking and it's connection with lung carcinoma and other illneses was proved. Four milions people die every year owing to tobacco smoking. My bachelor work considers problem of smoking in 2 aspects. Literature retrieval which is the main part is focused on the history and prevalence of smoking and smoking conventions in the Czech republic and in the World. It describes prevalence of smoking with respect of age, sex, educational level, geographical specifics, and other social and cultural determinants. Practical part of the work is questionary research which was accomplished among second grade students at primary schools. Its objective is to answer specific question regarding smoking of children and their parents. Research was carried out at selected primary schools in Bilina. For instance our principal interestest were numbers of regulary smoking children and what age they...
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Role of aerosol in climate change
Švátora, Milan ; Hůnová, Iva (advisor) ; Hovorka, Jan (referee)
Atmospheric aerosol is a suspension of liquid or solid particles or their mixture in the atmosphere. Tropospheric aerosols can get into the air from its natural sources or from anthropogenic sources. Release of carbon dioxide from burning fossil fuels and organic and elemental carbon from biomass burning are the major anthropogenic sources of aerosols. Primary aerosols have a direct source of emissions (dust from quarries or from land, sea salt particles in the waves, volcanic ash during volcanic eruptions). Secondary aerosols are formed by chemical reactions of substances in the atmosphere, which converts the gas particles - so- called conversion of gases to particles (formation of nitrates by oxidation of nitrogen oxides and sulfates from sulfur dioxide). Atmospheric aerosol is an important component of the atmosphere and contributes to significant atmospheric events, such as precipitation formation and precipation fall, radiation balance of Earth. Aerosols can affect the radiation balance of the Earth in two ways. First, through absorption and scattering of shortwave and long wave radiation - so-called direct effect. Or serve as condensation nuclei on which water is condenses. Aerosols can affect formation, quantity, length of existence and radiation properties of clouds - so-called indirect effect. In...
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Odour nuisance assessment in the CR
Vančurová, Andrea ; Hůnová, Iva (advisor) ; Kalíková, Květa (referee)
The aim of this work is to monitor the issue of odorous substances in the Czech Republic. In most cases, the main source of information are studies prepared at the request of the municipal or city authorities. Individual areas affected with this problem, those that I focused on in this work, were selected according to numbers of inducements and complaints from local residents. The introduction of the theoretical part deals with the anatomy of the olfactory system and the reaction of brain perceptions on odour stimulus. Furthermore, I describe the possibilities of measuring odours. Due to low concentrations of odours the least used method is gas chromatography; another option is olfactometry, which is based on the principle of mixing pre-determined concentration of an odorant with neutral gas. In the studies that are the main source of this work, I used the method of questionnaires that are consisted of evaluations of the smell from the locals. Moreover, I also described the procedure of filing in complaints about odours in the neighborhood of residence and its support in the law. The core of the practical part are the complaints of people that were submitted to the Czech Environmental Inspectorate for the years 2006 to 2009. Includes both specific businesses that are repeat complaints and fines of CZK 100...
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Trends in composition of atmospheric precipitation and deposition in Europe
Šimková, Petra ; Hůnová, Iva (advisor) ; Maznová, Jana (referee)
This bachelor thesis describes the historical development of emissions and their associated composition of atmospheric precipitation and atmospheric deposition in Europe. It is the work with review character, which summarizes and evaluates current knowledge of the majority components of atmospheric deposition. It relies particularly on articles and a summary reports of monitoring networks devoted to the large time horizon. At the beginning part of this work are defined the major components of atmospheric deposition. In another part is described composition of atmospheric precipitation, sampling dry and wet deposition and subsequent chemical analysis. The main part is devoted to evaluate the development of emission and sputtering of the main trends of acidifying compounds, and basic cations in Europe. Emission and deposition trends are divided into time periods, which were defined in relation to the development of historical, political or economic situation. Another criterion in the evaluation of trends in the composition of atmospheric precipitation and atmospheric deposition was the State's geographical position within Europe. There are summarized the results of studies on the deposition trends across Europe, but the main attention is devoted to the differences between Western and Eastern Europe...
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Trends of ambient ozone in the Northern hemisphere
Bučková, Nicole ; Hůnová, Iva (advisor) ; Hovorka, Jan (referee)
The development of ground-level ozone concentrations is currently hotly debated topic. Ozone itself is highly toxic and has strong oxidizing effects. Ozone has negative impact on human health, but also on vegetation. In addition ozone is one of the most important greenhouse gases causing the greenhouse effect. The Council of Europe decided to limit its increasing tendency by the release of Directive 2002/3/EC. Limits that are set in this Directive are binding for all Member States without exception and breach of these limits is enforceable by law. However as a result of increased anthropogenic activities, particularly increased consumption of fossil fuels and the development of industrialization, those limits are very often breached. Especially in summer when is solar radiation is most intense. This suggests that the highest ozone concentrations are in southern Europe. North Europe has problems with intercontinental transport of ozone. Concentration of ozone is dependent on many factors - the weather conditions, the geography but also the impact from human activity. This paper describes the development of ground-level ozone concentrations in various regions in Europe and North America. In writing this work, I come out mainly from foreign studies that address this topic. Keywords: ozone,...
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Air quality in schools
Hromádka, Jiří ; Braniš, Martin (advisor) ; Hůnová, Iva (referee)
A lot of scientific articles were published about the indoor air quality during the last decade. It is proven that high concentrations of particulate matter and problems connected with poor ventilation conditions can cause health effects to people who are sensitive to them. Children are one of the groups at risk. They spend a lot of time at home and also at school, so the air quality at schools is an important issue. This work contains a review of scientific papers concerning this issue. It discusses the factors influencing indoor air quality, mainly concentration of particulate matter and carbon dioxide. Other factors were also chosen: the age of the school building and its location, the seasonality, the number and level of activity of pupils, floor carpeting and the amount of air circulation in the classrooms. The preliminary study tries to prove these theories. The concentration of PM10 and CO2, the temperature and the relative humidity were measured in three classrooms at one primary school in Prague. The results show that higher concentration of particulate matter is correlated with higher level of activity of pupils. Also poor ventilation leads to the higher concentration of carbon dioxide and poor air quality. It was proven that there is a minimal correlation between indoor and outdoor...
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Surface ozone as a factor of oxidative stress in mountain forests.
Bendáková, Hana ; Hůnová, Iva (advisor) ; Matoušková, Leona (referee)
This study presents mountain forest Norway spruce (Picea abies) injured by surface ozone and oxidative stress. Norway spruce is not a sensitive species but it is the most representative tree in our country and this is the reason to pay attention on its injury. Study was connected to the ozone measurement by CHMI in Jizerske mountains. Aim of our study was to find influence of surface ozone on the forest and show correlation between ozone concentrations, altitude and Norway spruce injury. Ozone concentrations are growing with the altitude. Increasing percentage of injury with growing concentrations and altitude was expected. Needles were collected at the altitude 750-1100 meters. Collected needle years were 2006, 2007 and 2009. The 2009 year was not evaluated because no symptoms were found. Injury was observed on the maroscopical, microscopical and biochemical level. Visual injury was assessed by percentage of injured needle surface by chlorosis and necrosis. Microscopical analysis studied injury on cross and longitudinal sections of needles. On the longitudinal sections were visible typically bone-cells. These cells have lost its shape by ozone stress and were narrowed in its width. Bone-cells were best visible near the stomata. Four symptoms were observed on the cross sections: tannin...
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Estimation of exposure index for surface ozone AOT40 from diffusive sampler measurements
Pavlíková, Monika ; Hůnová, Iva (advisor) ; Matoušková, Leona (referee)
The study summerizes methods of ozone AOT40 index estimation from time intergarated passive sampler measurements in forests. Ground-level ozone is a highly phytotoxic atmospheric pollutant. In recent years negative impacts of elevated concentrations of ground-level ozone on vegetation and ecosystems have been studied and atmospheric levels of ozone have been measured. There is a noticeable negative impact of elevated concentrations of ground-level ozone on forests in the Czech Republic, mainly in rural areas that are far away from the emission sources. The AOT40F exposure index is a tool to assess the geographical areas with vegetation potentially at risk due to elevated ground-level ozone concentrations. The AOT40 index is the accumulated hourly exposure during daytime hours above cut-off concentration of 40 ppb, during the growing season. Passive samplers are used for measuring ground-level ozone in high spatial resolution. Passive samplers are easy to use. However this metod provides time intergrated values of pollutant concentrations (1-2 weeks). It is not possible to estimate AOT40 index by using just data of mean ozone concentrations over the sampling period. Three methods were used to estimate the exposure index AOT40F for forests by mean ozone concentrations measured in the Jizerské Hory...
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Long-term analysis of major ambient air pollutants in the Czech Republic
Šmejkalová, Marie ; Hůnová, Iva (advisor) ; Braniš, Martin (referee)
The thesis evaluates the long-term development of concentration of major air pollutants (sulphur dioxide, nitrogen oxides and particulate matter) at 17 air pollution monitoring stations. Chosen stations include automated monitoring as well as manual measuring stations and the locales cover the range from nature background stations (CR) to industrial and transport sites (in polluted areas of CR). The development of air pollution on the representative set of measurements is supplemented by the progress of pollution inventory of SO2, NOX and particulate matter from man-caused sources, and present state and development of pollution of precipitation and wet deposition in recent years. The pollution data was processed using monthly average concentrations by basic statistical methods of comparing multiple samples and time-series data analysis. Contemporary progress in recent years was considered in evaluation of air pollution, plus progress in the 90s characterised by pronounced changes and preceding period. The surveilled period is concerned mainly with problematics of SO2, from the trend of growing concentrations, across slight decline, followed by rapid decline in the course of the 90s till the present, when the SO2 moves gradually out of focus. The magnitude of decline depends on the locale pollution,...
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