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Lichens and eutrophication
Jadrná, Iva ; Svoboda, David (advisor) ; Malíček, Jiří (referee)
Eutrophication is a process of organic nutrients enrichment in an ecosystem, especially nitrogen and phosphorus. This bachelor thesis is dealing with the influence of eutrophication on lichens, especially with the effect of nitrogen compounds in the air and the effect of the combination of nitrogen compounds with phosphorus on epiphytic lichens. Eutrophication is defined and information is provided on changes in abundance and diversity of lichen cover. The mechanisms of eutrophication tolerance in lichens are also described. Key words: lichens, epiphytes, eutrophication, ammonia, ammonium ions, nitrogen oxides, phosphorus
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Biology of epiphytic bryophytes: methods of study
Reitschmiedová, Erika ; Soldán, Zdeněk (advisor) ; Novozámská, Eva (referee)
This thesis is aimed to provide basic description and summary of methods used to study biology/ecology of bryophytes, especially epiphytes. Described methods include study of mosses and liverworts; hornworts are not included due to the fact that their epiphytic form is not known. There are five chapters in this thesis, all of them are primarily focused on description of basic or most useful methods for studying phenology, growth, bioindication and environmental conditions, e.g. light and water relationship measurement as well as bark pH measurement. The last one, "Forms and Strategies", is only terminological and it includes terms of life and growth forms and life strategy which are used in studying colonies of bryophytes.
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Biotic interactions in epiphytic lichen communities
Černajová, Ivana ; Svoboda, David (advisor) ; Peksa, Ondřej (referee)
The objective of my bachelor's thesis is to review available literature on biotic interactions in epiphytic lichen communities. At first the epiphytic habitat is defined. The next part deals with the interactions, specifically competition and predation. Lichens compete for light and space among each other and with other cryptogams at the same time. There are a few known mechanisms of competition, most of them being based on overgrowing of thalli and chemical action. Thallus morphology, growth rate and content of allelochemicals are the main traits determining success in competition. Competitive abilities depend on various abiotic factors as well as on total composition of the community. Lichens are forced to invest in chemical defence by the presence of herbivores and parasites. Distribution of the defence substances matches the optimal defence theory. There is numerous evidence that biotic interactions modify characteristics of both individuals and species, mainly considering the secondary metabolites content and the width of the realized ecological niche. Competitors and predators may determine species distribution. The thesis summarises the knowledge of the mechanism, character and impact of the competition and predation in epiphytic lichen communities. Key words: lichens, cryptogams, epiphytes,...
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Lichens and eutrophication
Jadrná, Iva ; Svoboda, David (advisor) ; Malíček, Jiří (referee)
Eutrophication is a process of organic nutrients enrichment in an ecosystem, especially nitrogen and phosphorus. This bachelor thesis is dealing with the influence of eutrophication on lichens, especially with the effect of nitrogen compounds in the air and the effect of the combination of nitrogen compounds with phosphorus on epiphytic lichens. Eutrophication is defined and information is provided on changes in abundance and diversity of lichen cover. The mechanisms of eutrophication tolerance in lichens are also described. Key words: lichens, epiphytes, eutrophication, ammonia, ammonium ions, nitrogen oxides, phosphorus
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Biology of epiphytic bryophytes: methods of study
Reitschmiedová, Erika ; Soldán, Zdeněk (advisor) ; Novozámská, Eva (referee)
This thesis is aimed to provide basic description and summary of methods used to study biology/ecology of bryophytes, especially epiphytes. Described methods include study of mosses and liverworts; hornworts are not included due to the fact that their epiphytic form is not known. There are five chapters in this thesis, all of them are primarily focused on description of basic or most useful methods for studying phenology, growth, bioindication and environmental conditions, e.g. light and water relationship measurement as well as bark pH measurement. The last one, "Forms and Strategies", is only terminological and it includes terms of life and growth forms and life strategy which are used in studying colonies of bryophytes.
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Biotic interactions in epiphytic lichen communities
Černajová, Ivana ; Svoboda, David (advisor) ; Peksa, Ondřej (referee)
The objective of my bachelor's thesis is to review available literature on biotic interactions in epiphytic lichen communities. At first the epiphytic habitat is defined. The next part deals with the interactions, specifically competition and predation. Lichens compete for light and space among each other and with other cryptogams at the same time. There are a few known mechanisms of competition, most of them being based on overgrowing of thalli and chemical action. Thallus morphology, growth rate and content of allelochemicals are the main traits determining success in competition. Competitive abilities depend on various abiotic factors as well as on total composition of the community. Lichens are forced to invest in chemical defence by the presence of herbivores and parasites. Distribution of the defence substances matches the optimal defence theory. There is numerous evidence that biotic interactions modify characteristics of both individuals and species, mainly considering the secondary metabolites content and the width of the realized ecological niche. Competitors and predators may determine species distribution. The thesis summarises the knowledge of the mechanism, character and impact of the competition and predation in epiphytic lichen communities. Key words: lichens, cryptogams, epiphytes,...
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