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Interaction of lichens and invertebrates with emphasis on mites
Vtípilová, Věra ; Steinová, Jana (advisor) ; Černajová, Ivana (referee)
Lichens interact with many groups of invertebrates. Acari (mites), Gastropoda (gastropods), Rotifera (rotifers), Nematoda (nematodes), Tardigrada (tardigrades), Protozoa (protists), Collembola (springtails) and Insecta (insects), especially Psocoptera (book and bark lice), Lepidoptera (butterflies and moths) and Coleoptera (beetles) represent the most common groups. These animals use lichens as a shelter and food. Lichens have different defence mechanisms, for example, secondary metabolites. On the other hand, invertebrates often mediate the dispersal of lichens. Some lichens can grow on shells or a body surface of living invertebrates. In my thesis, I describe individual groups of invertebrates that interact with lichens, and I mention specific examples of these interactions. A special emphasis is given on mites because they are one of the most important consumers of lichens, and I will pay attention to them in my diploma thesis.
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Lichens on metal-rich substrates with emphasis on serpentinites
Ghlimová, Heda ; Steinová, Jana (advisor) ; Peksa, Ondřej (referee)
Serpentinite is an ultramafic rock covering about 1 % of the Earth's surface. Serpentinite contains a high content of heavy metals such as Ni, Cr, Co and, conversely, low content of major nutrients N, P, K. The high concentration of Mg reduces the availability of Ca to plants. Serpentinites are not distinguished only by their chemistry - they are also, for example, poorly thermally conductive and soils that form on the serpentine subsoil are considered infertile. This complex of properties causes the formation of so- called serpentinomorphoses in vascular plants and also promotes the development of endemism. However, these adaptations do not occur in fungi and in lichens and bryophytes they occur only partially. This bachelor thesis summarizes the basic physiological mechanisms by which myco- and photobionts ensure the survival of lichens on substrates with high content of heavy metals - it is above all extracellular absorption of metals (binding to cell wall ligands), intracellular absorption (and subsequent detoxification with metallothionein and phytochelatins), and exclusion of metals on the surface of mycobiont hyphae or on the surface of the thallus (binding to oxalates and secondary metabolites). The bachelor thesis also summarizes the morphological adaptations that occur in lichens in...
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Microclimate as a driver of species distribution and community composition of bryophytes compared with lichens
Růžičková, Anna ; Man, Matěj (advisor) ; Starosta, Jakub (referee)
This bachelor thesis deals with the influence of microclimate on species distribution and composition of bryophyte and lichen communities. It defines the term microclimate, characterizes the specific properties of bryophytes responsible for their sensitivity to microclimatic conditions and includes a comparison of the role of individual microclimatic factors in controlling the distribution of bryophytes and lichens. The key microclimatic factors for bryophytes are humidity and air temperature, but the significance of each varies between functional groups of species and depending on the type of biome. With the available portable measuring devices with large battery capacity and memory storage, it is now possible to measure in-situ microclimate for the long-term and also with high spatial and temporal resolution. Despite that, there are currently only 12 bryological studies that provide continuously measured field microclimatic data on small spatial scales. The main part of the thesis summarizes these studies and compares the methodologies used. The paper can serve as a starting material for designing bryological microclimatic studies.
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Diversity and phylogeny of symbiotic partners in zeorin-containing red-fruited Cladonia species.
Steinová, Jana ; Škaloud, Pavel (advisor) ; Pérez-Ortega, Sergio (referee) ; Vondrák, Jan (referee)
Lichens are a classic example of mutualistic symbiotic associations, yet the views on lichen symbiosis have changed considerably during the last fifty years. Nowadays, lichens are generally understood to be microecosystems consisting of several symbiotic partners which contribute in different ways to the prosperity of the whole system and which differ by the strength of their bond to other symbiotic partners. The level of knowledge of the individual partners (mycobionts vs. photobionts vs. bacteria) varies greatly in terms of their specificity, diversity and in the forces that shape this diversity. The main aim of this work was to reveal the diversity of organisms participating in lichen symbiosis and to better understand the biological forces which shape this diversity. We worked with a relatively common lichen group, zeorin-containing red-fruited Cladonia species, and specifically, we focused on the mycobionts, photobionts and bacteria that participate in this association. During the course of the study, it became apparent that species delimitation, which is a fundamental requirement for accurate diversity estimates, is another topic that requires further research. Our analyses revealed that species circumscription of most of recently recognized Cladonia mycobionts cannot by supported by...
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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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