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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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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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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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