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What we know about salty ecosystems of the Europe and their distribution, origin and history?
Šemberová, Kristýna ; Stančík, Daniel (advisor) ; Špryňar, Pavel (referee)
Salt marsh and meadow vegetation belong to very specific type of azonal ecosystem. There develop is made possible because of high concentrations of salts in the substrate. On the coast the development results from the contact of shore area with seawater. The existence of inland salt meadow is depending on specific climatic, geological and pedological conditions. Plants (halophytes) developed specific types of adaptation to resist high level of salinity and other extreme conditions of their habitat. During evolution occurred this type of adaptation in several phylogenetic lineages independently. Structure and physiognomy of salt marsh and meadow vegetation depend on the degree of salinity of the substrate and we can distinguish several zones on this gradient. Climatic conditions during the pleniglacial were very favourable for the development of halophyte vegetation. The oldest salt marshes, which played role of the refuge, are located on the coast, but also in the inland of Central Asia. This kind of vegetation reaches also south part of Central and Eastern Europe. After glaciation and the arrival of the forest, big part of this vegetation disappeared. Some inland areas have been maintained thanks to a man, which has used them since Neolithic times as pastures. With the abolition of grazing,...
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Abiotic Stress Adaptation in Plantago: mechanisms of tolerance
Dvořáková, Iveta ; Konrádová, Hana (advisor) ; Lhotáková, Zuzana (referee)
Plants are exposed to many adverse factors during their life cycles. Abiotic stresses are significantly limiting plant growth and development. Abiotic stress response mechanisms involve compatible solute synthesis (e.g. sugars, sugar alcohols and amino acids). The aim of this study was to characterise the responses of plants from Plantago genus to different abiotic stresses (drought, salinity, cold and stress combination). The complete plants grew under in vitro conditions. I compared morphological parameters, selected metabolic parameters (carbohydrates balance and proline accumulation) under optimal conditions and stress exposure. This study was focused on plants from genus Plantago, because they differ from each other in their tolerance to the salinity. Both, the glycophyte and the halophyte species are described within this genus. Plantains produce besides widespread soluble carbohydrates (sucrose, glucose, fructose) also sugar alcohol sorbitol, which has been reported as a significant component of the stress response. In addition, the reaction of plants to different carbon and energy sources was tested. More severe growth inhibition of the glycophyte Plantago lanceolata compared to the halophyte P. maritima was observed under salt treatment. Significant accumulation of sorbitol was observed...
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Autecological study of selected Cretaceous plants using stable Carbon isotopes
Zahajská, Petra ; Kvaček, Jiří (advisor) ; Diefendorf, Aaron (referee)
1 Abstract This thesis presents an analysis of fossil plants from the Cenomanian Peruc-Korycany Formation of the Bohemian Cretaceous Basin and from the Bückeberg Formation of the Lower Saxony Basin in Germany. Based on earlier studies, both areas provide sediments that are considered to have developed in tidally influenced fluvial systems. Studied fossil plants are represented by ginkgoalean plant leaves (Ertemophyllum, Tritaenia), branches of conifers (Frenelopsis) and lauroid angiosperms (Eucalyptolaurus). Frenelopsis, Eretmophyllum and Tritaenia are considered to be halophytic plants, while Lauroid angiosperms were considered to grow in fresh water conditions. The fossil plants were studied using cuticle analysis and two methods of stable carbon isotope analysis: Bulk carbon isotope analysis and Compound Specific Isotope analysis. For cuticle analysis samples were observed and documented macroscopically and microscopically. To specify the environmental conditions, recent samples from three salt marshes in Great Britain were studied and analysed using the same methods as the fossil samples. The data from all observations and measurements were processed and their interpretation supported the modelled environment based on the sedimentological data. Frenelopsis were growing in a haline environment with low...
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Autecological study of selected Cretaceous plants using stable Carbon isotopes
Zahajská, Petra ; Kvaček, Jiří (advisor) ; Diefendorf, Aaron (referee)
1 Abstract This thesis presents an analysis of fossil plants from the Cenomanian Peruc-Korycany Formation of the Bohemian Cretaceous Basin and from the Bückeberg Formation of the Lower Saxony Basin in Germany. Based on earlier studies, both areas provide sediments that are considered to have developed in tidally influenced fluvial systems. Studied fossil plants are represented by ginkgoalean plant leaves (Ertemophyllum, Tritaenia), branches of conifers (Frenelopsis) and lauroid angiosperms (Eucalyptolaurus). Frenelopsis, Eretmophyllum and Tritaenia are considered to be halophytic plants, while Lauroid angiosperms were considered to grow in fresh water conditions. The fossil plants were studied using cuticle analysis and two methods of stable carbon isotope analysis: Bulk carbon isotope analysis and Compound Specific Isotope analysis. For cuticle analysis samples were observed and documented macroscopically and microscopically. To specify the environmental conditions, recent samples from three salt marshes in Great Britain were studied and analysed using the same methods as the fossil samples. The data from all observations and measurements were processed and their interpretation supported the modelled environment based on the sedimentological data. Frenelopsis were growing in a haline environment with low...
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Abiotic Stress Adaptation in Plantago: mechanisms of tolerance
Dvořáková, Iveta ; Konrádová, Hana (advisor) ; Lhotáková, Zuzana (referee)
Plants are exposed to many adverse factors during their life cycles. Abiotic stresses are significantly limiting plant growth and development. Abiotic stress response mechanisms involve compatible solute synthesis (e.g. sugars, sugar alcohols and amino acids). The aim of this study was to characterise the responses of plants from Plantago genus to different abiotic stresses (drought, salinity, cold and stress combination). The complete plants grew under in vitro conditions. I compared morphological parameters, selected metabolic parameters (carbohydrates balance and proline accumulation) under optimal conditions and stress exposure. This study was focused on plants from genus Plantago, because they differ from each other in their tolerance to the salinity. Both, the glycophyte and the halophyte species are described within this genus. Plantains produce besides widespread soluble carbohydrates (sucrose, glucose, fructose) also sugar alcohol sorbitol, which has been reported as a significant component of the stress response. In addition, the reaction of plants to different carbon and energy sources was tested. More severe growth inhibition of the glycophyte Plantago lanceolata compared to the halophyte P. maritima was observed under salt treatment. Significant accumulation of sorbitol was observed...
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Sorbitol role in abiotic stress response
Dvořáková, Iveta ; Konrádová, Hana (advisor) ; Janská, Anna (referee)
Many adverse factors affect plants during their life cycle. This bachelor thesis is focused on the influence of abiotic stress on plants. Attention is paid to drought and salinity stresses which are the main causes of osmotic stress, and to the mechanisms which help plants to cope with these adverse factors. Common reaction of plants to osmotic stress is synthesis and accumulation of substances which contribute to keeping cell integrity. These substances are called compatible solutes. This thesis is focused on sorbitol - sugar alcohol belonging to this group of substances. In plants that synthesize sorbitol naturally, it provides advantage under exposure to abiotic stresses as it serves as an osmoticum and/or an osmoprotectant and reduces oxidative stresses. Finally, based on the knowledge about participation of sugar alcohols in the stress reactions, modifications of plant metabolisms potentially increasing stress tolerance are discussed. Powered by TCPDF (www.tcpdf.org)
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What we know about salty ecosystems of the Europe and their distribution, origin and history?
Šemberová, Kristýna ; Stančík, Daniel (advisor) ; Špryňar, Pavel (referee)
Salt marsh and meadow vegetation belong to very specific type of azonal ecosystem. There develop is made possible because of high concentrations of salts in the substrate. On the coast the development results from the contact of shore area with seawater. The existence of inland salt meadow is depending on specific climatic, geological and pedological conditions. Plants (halophytes) developed specific types of adaptation to resist high level of salinity and other extreme conditions of their habitat. During evolution occurred this type of adaptation in several phylogenetic lineages independently. Structure and physiognomy of salt marsh and meadow vegetation depend on the degree of salinity of the substrate and we can distinguish several zones on this gradient. Climatic conditions during the pleniglacial were very favourable for the development of halophyte vegetation. The oldest salt marshes, which played role of the refuge, are located on the coast, but also in the inland of Central Asia. This kind of vegetation reaches also south part of Central and Eastern Europe. After glaciation and the arrival of the forest, big part of this vegetation disappeared. Some inland areas have been maintained thanks to a man, which has used them since Neolithic times as pastures. With the abolition of grazing,...
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