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Adaptations of epiphytic plants to water and nutrient uptake
Oppeltová, Soňa ; Ponert, Jan (advisor) ; Neuwirthová, Eva (referee)
Epiphytes are plants that grow on other plants but do not parasitize them. Because of irregular availability of water and nutrients, epiphytes evolved specific adaptations. These adaptations enable fast water and nutrient uptake and their efficient storage. For the uptake of water epiphytes evolved especially adaptations of roots and leaves. Roots produce velamen radicum and leaves develop specific absorptive trichomes. The uptake of water is related with the uptake of nutrients because first drops of rain are nutrient relatively rich. Another source of nutrients is organic material which falls from trees. Some epiphytes can retain it and acquire nutrients from its decomposition. Animals can also help epiphytes with nutrition. They can provide urea which is probably very essential for many bromeliads. Animals can also live in more specific symbioses with epiphytes, the most common being the symbiosis with ants. Epiphytes evolved many adaptations, but some of them are poorly understood.
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Carbon allocation in evergreen and decidious temperate tree species under the elevated concentration CO2 and O3
Neuwirthová, Eva ; Albrechtová, Jana (advisor) ; Konrádová, Hana (referee)
An ongoing increase in atmospheric CO2 concentrations and tropospheric O3 is expected in coming years. These changes are mostly caused by anthropogenic activities and influence remarkably not only plants but the climate on the Earth. Physiological processes in plants determining carbon assimilation and allocation in plant organs are changing in a consequence of variations of these gases in the environment. Tree species represent importatnt C pools and changes in C allocation may effect their sink capability in the global C cycle.Increased CO2 concentration in the atmosphere often leeds to incereased rate of photosynthesis lowered photorespiration what in turn may lead to enhanced C storage in plant biomass. The C storage into sinks is mediated through the assimilation organs, which are disturbed by O3. Ozone is toxic to plants and trees are due to their longevity exposed to ozone influence repeatedly for long term. The response to increased CO2 and O3 concentrations, is the most commonly investigated on two typical representatives of European temperate species: deciduous European beech (Fagus sylvatica L.) and coniferous Norway spruce (Picea abies L. Karst.) The aim of the present review was to summarize the knowledge about the effects of increased concentrations of CO2 and O3 acting separately or in...
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Optical properties of the leaf in relation to its anatomical traits
Neuwirthová, Eva ; Albrechtová, Jana (advisor) ; Tomášková, Ivana (referee) ; Písek, Jan (referee)
Plant functional traits at the leaf level are commonly used to predict ecosystem responses to environmental factors and describe global climate change processes at the ecosystem level. Plant functional traits include both leaf biophysical traits (e.g., photosynthetic pigment content and water content) and structural traits (e.g., leaf thickness and proportion of photosynthetic and non-photosynthetic tissues). Leaf biophysical and structural traits can be detected either destructively in the laboratory or non-destructively using leaf optical properties. Although estimating chlorophyll content from leaf optical properties is a well-established methodology, the influence of leaf structure and internal anatomy on leaf optical properties has only been thoroughly studied in the last two decades. The papers included in my thesis and my thesis itself are mostly focused on the study of typical European deciduous trees of temperate and hemiboreal forests with leaves having a dorsiventral structure (i.e., the mesophyll is differentiated into palisade and spongy parenchyma). Furthermore, my thesis includes a study on the effect of leaf surface structural traits on optical properties. In this study, two groups of phylogenetically close herbs with comparable internal leaf structure were used (mutants of...
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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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Carbon allocation in evergreen and decidious temperate tree species under the elevated concentration CO2 and O3
Neuwirthová, Eva ; Albrechtová, Jana (advisor) ; Konrádová, Hana (referee)
An ongoing increase in atmospheric CO2 concentrations and tropospheric O3 is expected in coming years. These changes are mostly caused by anthropogenic activities and influence remarkably not only plants but the climate on the Earth. Physiological processes in plants determining carbon assimilation and allocation in plant organs are changing in a consequence of variations of these gases in the environment. Tree species represent importatnt C pools and changes in C allocation may effect their sink capability in the global C cycle.Increased CO2 concentration in the atmosphere often leeds to incereased rate of photosynthesis lowered photorespiration what in turn may lead to enhanced C storage in plant biomass. The C storage into sinks is mediated through the assimilation organs, which are disturbed by O3. Ozone is toxic to plants and trees are due to their longevity exposed to ozone influence repeatedly for long term. The response to increased CO2 and O3 concentrations, is the most commonly investigated on two typical representatives of European temperate species: deciduous European beech (Fagus sylvatica L.) and coniferous Norway spruce (Picea abies L. Karst.) The aim of the present review was to summarize the knowledge about the effects of increased concentrations of CO2 and O3 acting separately or in...
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