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Lichen ecology in the relationship to functional diversity and genome size
Konečná, Eliška ; Malíček, Jiří (advisor) ; Palice, Zdeněk (referee)
Eliška Konečná Lichen ecology in the relationship to functional diversity and genome size Abstract This bachelor thesis in its first part summarises and characterizes lichen functional traits and sums up known relation between particular traits and ecological factors of the enviroment. Second part of the thesis focuses on question of genome measurment in general and than summarises known information about lichen genom size. In the second part there is partial focus on relation between genom size and ekology of organisms as well, which could become focus of some study in the future. Key words: functional traits, lichens, mycobiont, genome size
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Lichenometry as a method and its relevance
Pelant, Filip ; Svoboda, David (advisor) ; Halda, Josef (referee)
Lichenometry is a constantly developing method (or set of methods) of relative and absolute dating of geological and anthropogenic formations, based on analysis of crustose lichens. It operates with an assumption that the larger the thallus is, the older the lichen is. But the relation between size and age (known as "growth rate") is far from being linear, and lichenometry has long attempted to find a way of describing this relation properly and universally. For this purpose, lichenometry uses direct and indirect methods - by repeated measurements of the same lichen individuals over time, or by comparison to individuals growing on substrates of known age (e.g. by using radiocarbon method). There is an ongoing controversy about aging and age calibration since the inception of the lichenometry field, but especially in this century. Strong criticism has been expressed about lichenometry, questioning the very principles of the method and consequently undermining all the results of lichenometry so far. The goal of the present bachelor thesis is to present the method with its approaches and to address the criticism. At the same time I aim to highlight recent trends in the field that seek to improve the methods toward more reliable lichenometric dating, and to encourage the use of the methods as so...
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Raman spectrometry of pigments of cyanobacteria, algae and lichens in the astrobiology context
Kovács, Michal ; Jehlička, Jan (advisor) ; Osterrothová, Kateřina (referee)
This work deals with the possibility of Raman spectroscopical identification of selected biomarkers of extremophile species. It focuses mainly on selected cyanobacteria, algae and lichens with an emphasis on the ability to detect carotenoids. These pigments exhibit three characteristic bands of Raman spectra which represent stretching vibrations C=C; C-C and bending vibration C-CH3 in molecules of carotenoids. Raman spectra were measured not only by laboratory microspectrometers (λ - 514 nm and 532 nm), but also by portable and handheld spectrometers (λ - 532 nm, 785 nm and 700 - 1100 nm). In the case of cyanobacteria, the spectroscopical analysis was performed also on the fractions obtained by high performance liquid chromatography (HPLC). This work critically evaluates the possibilities of Raman spectroscopy to identify the carotenoids of cyanobacteria, algae and lichens. Besides the signal of carotenoids, interpretation of other bands in the Raman spectra corresponding to the presence of other biomarkers is given here for selected samples. The obtained Raman spectra of carotenoids should be interpreted with great caution, because of the ifluence of several factors, which potentially cause unsystematic shifts in the positions of Raman bands (carotenoids bond in biological tissue, interactions with...
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The effect of heavy metals on the physiology of lichens
Hrdinová, Aneta ; Peksa, Ondřej (advisor) ; Svoboda, David (referee)
Lichens are known for their sensitivity to environmental changes, however, the tolerance to different changes may vary among particular taxa. There are lichen species extremely sensitive as well as very tolerant to pollution. The species growing in areas with a higher content of heavy metals belong to the second group. These sites may by of natural origin (ore), but very often they have arose as a result of anthropogenic activities (imissions in industrial and urban areas, various heaps etc.). The interaction between photobiont and mycobiont in the thallus can probably explain the success of lichens in environment enriched by heavy metals. The stress caused by heavy metals leads to increasing production of reactive oxygen species in cells of photobiont and mycobiont. Reactive oxygen species cause lipid peroxidation, damage of proteins and nucleic acids, and the degradation of chlorophylls. Although mycobiont provides the photobiont cells partial protection (particularly thanks to binding of metal ions to the cell wall and the formation of water-insoluble secondary metabolites), photobiont is exposed to high amounts of metals. Therefore, both symbionts have developed a range of detoxification mechanisms. The aim of this thesis was to summarize the findings on the effect of heavy metals on the...
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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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Biogeographical position of the Tristan da Cunha archipelago based on floristic records.
Vinšová, Petra ; Kopalová, Kateřina (advisor) ; Žárský, Jakub (referee)
The archipelago Tristan da Cunha is situated in the South Atlantic Ocean, about midway between South America and southern tip of Africa. It represents one of the least disturbed temperate island systems in the world, supports many endemic plant and animal species. Although the locality is interesting by many aspects, many fields still remain under-studied. This bachelor thesis presents a synthesis of available literature about the archipelagos non-marine non-vascular floras, which are of a great diversity, but mostly still overlooked by scientist. For some of them were made lists of taxa present. Further, the distributional ability and patterns of this plant groups are discussed. KEYWORDS: Tristan da Cunha; Oceanic islands; Botanic; Distribution; Island Biogeography; Lichens; Mosses; Liverworts and Hornworts; Diatoms;
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Lichens and (heavy) metals
Hrdinová, Aneta ; Peksa, Ondřej (advisor) ; Malíček, Jiří (referee)
My thesis is focused on liches and heavy metals. In first part includes the general characteristics of lichens, the short description of their biology, morphology and anatomy. The next part is focused on the characteristics of the methods of absorption of metals by lichens, their physiological effects on the body and the mechanisms of defense against the toxicity of metals lichens. The work includes the list of species of lichen, and their relationships to particular heavy metals. Key words: Lichens, heavy metals, metal tolerance, detoxification, copper
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Lichens growing on diabasic rocks
Lenzová, Veronika ; Svoboda, David (advisor) ; Bouda, František (referee)
This bachelor thesis is a review of available literature about the lichens growing on diabasic rocks. Diabasic rocks are volcanic rocks of upper proterozoic and lower paleozoic age. They occur in the Czech Republic in Barrandien and Nízký Jeseník areas only. The most investigated sites concerning lichens are the Berounka river valley and Prague region. Diabasic rocks are very suitable substrate for lichens due to specific properties and these rocks provide greater lichens diversity in comparison to the other substrates. This thesis contains list of 213 lichen species, which were published on diabasic rocks within the Czech Republic. According to the literature 3 lichen species have been found only on diabases in the country.
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Laboratory and image spectroscopy for mapping of selected rocks in peak areas of the Krkonoše Mountains
Kubečková, Jana ; Kupková, Lucie (advisor) ; Potůčková, Markéta (referee)
Laboratory and image spectroscopy for mapping of selected rocks in peak areas of the Krkonoše Mountains Abstract This thesis deals with geological mapping of selected rocks in peak areas of the Krkonoše Mountains. Four areas of interest were situated in two parts of Krkonše Mountains - on the west side it is the area of Vysoké kolo and Harrachovy kameny and on the east side there is the area of Sněžka and the area of Kozí hřbety. The main data were acquired by the hyperspectral sensor APEX. Ground spectral measurments of selected rocks and block fields were executed and the laboratory spectral measurments of geological samples and lichens were executed. Practical part aims at classification of rocks and lichens in selected areas using four classification methods: SAM, SID, MESMA and LSU. The spectral library is one of the outputs of this thesis. This spectral library contains the spectra of pure rocks and lichens and mixtured spectra of rocks and lichens. The output of this thesis is the comparation of used classification methods, the analysis of spatial and geological accuracy and evaluation of lichens influence on the classification results, spectral library and maps of classified rocks occurrence. Keywords: classification, block fields, hyperspectral data, spectral mixture, lichens, The Krkonoše Mountains
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Mollusc grazing and secondary metabolites of lichens
Černajová, Ivana ; Svoboda, David (advisor) ; Vondrák, Jan (referee)
In contrast to the much that is known about herbivory and its consequences, lichenovory has seldom been studied. Recently, studies confirming the anti-feedant role of lichen secondary metabolites were brought out and hypotheses considering the nature of these interactions were introduced. Also, a few papers dealing with the ecological consequences of lichenovory were published lately. My thesis was aimed on the secondary metabolites issue and the preferences of the lichen feeders in the natural conditions. Six epiphytic lichen species containing secondary compounds (Parmelia sulcata, P. saxatilis, Parmelina tiliacea, Melanelixia glabratula, M. subaurifera, M. glabra), two without them (Melanohalea exasperata, M. exasperatula) and two species of gastropods that naturally climb the trees to feed on lichens (Lehmannia marginata, Cochlodina cerata) were selected for grazing experiments. The deterring role of the lichen compounds was proven. These were also identified using thin-layer chromatography. Subsequently, a transplantation experiment was carried out. It was focused on specifying the preferences of lichen grazers in their natural habitat. The genus Melanohalea that does not contain any secondary metabolites was strongly prefered. No significant preferences among the other species used in the...
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