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Leaf structural changes induced by tropospheric ozone.
Češpírová, Zdeňka ; Lhotáková, Zuzana (advisor) ; Hála, Michal (referee)
Tropospheric ozone is an important pollutant formed by the photochemical reactions of ultraviolet radiation and nitrogenous. Recently, its concentration in the air is increasing due to the promoting climate change and antropogenic activities, mainly because of combustion of the fossil fuels. The ozone is highly reactive molecule degrading to the reactive oxygen species having negative effects on the leaf physiological functions and structure. Ozone penetrates the leaf through the stomata, thereafter it reacts with the cells and their singular compartments. The products formed due to ozone degradation are able to cause the disintegration of plasma membranes and other oxidative damage, for example accumulation of plastoglobuli inside the chloroplasts, changes in the shape of chloroplasts, mitochondria or peroxisomes. At the macroscopic level the visible lesions, chloroses and necroses are observed. In addition, the faster senescence of leaves is observed under the effect of ozone. The main aim of present thesis is to review knowledge of the ozone-induced changes in the leaf structure beginning on the cell structure level and ending at the whole plant body level and to explain physiological mechanisms leading to these damages. Key words: ozone, oxidative stress, leaf structure, mesophyll, reactive...
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Anatomical study of shade and sun European beech leaf under elevated CO2.
Horská, Jana ; Lhotáková, Zuzana (advisor) ; Urban, Otmar (referee)
The present Master thesis focuses on evalution of CO2 concentration and irradiance on selected leaf anatomical parameters of European Beech (Common Beech) Fagus sylvatica L.. The process of photosynthesis is remarkably determined by numerous extrenal factors, among them by atmoshperic CO2 concentration and irradiance and is closely correlated with leaf anatomical parameters. One of these most important anatomical parameters affecting the net assimilation rate is an internal leaf surface, which corresponds to mesophyll area avialable for gas exhcange. Experimental material of the study was sampled from the leaves of juvenile trees of F. sylvatica planted in 2005 and growing under ambient (390 ppm, AC) and elevated (700 ppm, EC) CO2 concentrations on the experimental site of the Global Change Research Center AS CR at Bílý Kříž in the Beskydy Mountains. Sun and shade leaves were sampled from trees of both CO2 treatments in two seasons 3 years apart (2009 and 2012). To determine leaf anatomical parameters, the stereological methods were applied, which yield unbiased estimation of measured parameters, particularly the Fakir method for internal leaf surface determination. The EC effect was observed on the leaves sampled in 2009 only in the decrease of proportion of intercellular spaces in mesophyll. In...
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Changes in anatomy of coniferous needles in response to anthropogenic pollution
Štěpánová, Kristýna ; Albrechtová, Jana (advisor) ; Votrubová, Olga (referee)
The anatomical structure of conifer needles is affected by external enviromental conditions. From abiotic factors, apart of irradiation, main determining factors are drought and extreme temperatures belonging to factors of climate change. Anthropogenic pollution has a significant position among the external abiotic factors that cause changes in the structure of needles. At present, the main polluting compounds are tropospheric ozone, SO2, NOx and PM. Due to the effect of atmospheric pollutants, the proportion of individual tissues in the needle changes, so does the proportion of intercellular spaces and the internal structure of cellular organelles, especially chloroplasts. Mesophyll cells show signs of degradation, especially around the substomatal cavity. There appears a visible damage on the needle surface - chloroses and necroses. The process of senescence speeds up during the activity of stress enviromental factors, such as anthropogenic pollution. The main objective of the present Thesis is to gather knowledge about changes of conifer needle structure, caused by anthropogenic pollution, especially ozone, SO2 and NOx, in combination with climate change factors - drought and extreme temperatures. The review is focused on modifications on various anatomic hierarchical levels, from visible...
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How does the leaf structure determine the leaf optical properties.
Peychlová, Anna ; Lhotáková, Zuzana (advisor) ; Tylová, Edita (referee)
An internal leaf structure determines the way the light passes through the leaf and, thus, in this way it affects the use of the light in photosynthesis. The light reaching the leaf can be reflected, absorbed or transmitted. Leaf reflectance properties depend on the wavelength of irradiation and on the physical, structural and chemical properties of a leaf. Thereinafter, this Bachelor thesis briefly describes spectral methods used to study leaf optical properties. Furthermore, the thesis focuses on leaf anatomical structures and their effect on leaf optical properties, mainly in visible region of electromagnetic radiation (400-700 nm) and in near- infra-red region (700-2300 nm). The emphasis is given to the following anatomical properties and structures: epidermis, cuticle, trichomes, mesophyll structure, leaf thickness, chloroplast movement, chlorophyll content and distribution. The aim of the thesis is to summarize current knowledgeon this topic. Key words: leaf anatomy, leaf optical properties, reflectance, intercellular spaces, radiative transfer
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Leaf structural changes induced by tropospheric ozone.
Češpírová, Zdeňka ; Lhotáková, Zuzana (advisor) ; Hála, Michal (referee)
Tropospheric ozone is an important pollutant formed by the photochemical reactions of ultraviolet radiation and nitrogenous. Recently, its concentration in the air is increasing due to the promoting climate change and antropogenic activities, mainly because of combustion of the fossil fuels. The ozone is highly reactive molecule degrading to the reactive oxygen species having negative effects on the leaf physiological functions and structure. Ozone penetrates the leaf through the stomata, thereafter it reacts with the cells and their singular compartments. The products formed due to ozone degradation are able to cause the disintegration of plasma membranes and other oxidative damage, for example accumulation of plastoglobuli inside the chloroplasts, changes in the shape of chloroplasts, mitochondria or peroxisomes. At the macroscopic level the visible lesions, chloroses and necroses are observed. In addition, the faster senescence of leaves is observed under the effect of ozone. The main aim of present thesis is to review knowledge of the ozone-induced changes in the leaf structure beginning on the cell structure level and ending at the whole plant body level and to explain physiological mechanisms leading to these damages. Key words: ozone, oxidative stress, leaf structure, mesophyll, reactive...
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The effect of leaf structure on the leaf optical properties - Implication for water regime.
Neuwirthová, Eva ; Albrechtová, Jana (advisor) ; Rothová, Olga (referee)
Due to coal mining activities, heap substrates rich in clays with poor water permeability and lack of nutrients are relocated outside of mines representing hostile environment to the majority of vegetation. A material from the surface coal mines in Sokolov forming the Velká Podkrušnohorská Heap (VPS) form large locality showing characteristics of anthropogenically devasted landscape. The aim of the present study was to compare leaf structural and biochemical parameters with relation to a leaf reflectance of two pioneer tree species Salix caprea and Populus tremula with regard to leaf water regime and leaf adaptation to a water loss. From the methodological point of view, the study aimed on contribution to determine relation of selected leaf structural parameters to leaf reflectance what has not been intensively studied yet. The foliage of trees P. tremula and S. caprea grown on succession localities S2 a S3 for 30 years was used as a material for my study. The material was studied for its structure using the leaf cross sections nd abaxial epidermal strips (thickness of the leaf tissue layers and of a leaf, stomatal size density and area). Other studied parameters were contents of photosynthetic pigments, specific leaf area (SLA), water potential and leaf reflectance in regions of photosyntetically...
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Anatomical study of shade and sun European beech leaf under elevated CO2.
Horská, Jana ; Lhotáková, Zuzana (advisor) ; Urban, Otmar (referee)
The present Master thesis focuses on evalution of CO2 concentration and irradiance on selected leaf anatomical parameters of European Beech (Common Beech) Fagus sylvatica L.. The process of photosynthesis is remarkably determined by numerous extrenal factors, among them by atmoshperic CO2 concentration and irradiance and is closely correlated with leaf anatomical parameters. One of these most important anatomical parameters affecting the net assimilation rate is an internal leaf surface, which corresponds to mesophyll area avialable for gas exhcange. Experimental material of the study was sampled from the leaves of juvenile trees of F. sylvatica planted in 2005 and growing under ambient (390 ppm, AC) and elevated (700 ppm, EC) CO2 concentrations on the experimental site of the Global Change Research Center AS CR at Bílý Kříž in the Beskydy Mountains. Sun and shade leaves were sampled from trees of both CO2 treatments in two seasons 3 years apart (2009 and 2012). To determine leaf anatomical parameters, the stereological methods were applied, which yield unbiased estimation of measured parameters, particularly the Fakir method for internal leaf surface determination. The EC effect was observed on the leaves sampled in 2009 only in the decrease of proportion of intercellular spaces in mesophyll. In...
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