National Repository of Grey Literature 6 records found  Search took 0.01 seconds. 
Changes in epiphytic lichen biota in the Czech Republic with emphasis on current situation
Hronová, Nikola ; Malíček, Jiří (advisor) ; Palice, Zdeněk (referee)
During the last two centuries a significant change of lichen communities has happened in the Czech Republic. Important factors which had influencing the lichen biota in the past and recently are summarized in this bachelor thesis. Acid rain caused by high imissions of SO2 a NOx was the most important factors of change of species and remaining acidification of substrates is still influencing lichen communities. Until the end of 80's of 20th century acid rain was a dominant factor influencing lichens. Afterwards, thanks to drop of its intensity in 90's of 20th eutrophication and availability of nitrogen in landscape became dominant influencing factors. All these factors mainly affected the communities of macrolichens, and especially cyanolichens to such an extent that some species in the Czech Republic became extinct. Recently the increasing availability of nutrients has been supporting the spread of nitrophilous species. Due to decrease of SO2 emissions to values from the end of 19th century some areas have been recolonized and some endangered species have returned. The transformation of lichen communities has also been significantly affected by forest management and land use. Based on changing climate and change of natural habitats a further decline mainly of suboceanic species is expected. A more...
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
Diversity, ecology and methods of the research of lichens in old-growth forests in Central Europe
Malíček, Jiří ; Palice, Zdeněk (advisor) ; Guttová, Anna (referee) ; Pérez-Ortega, Sergio (referee)
1 Abstract Forests are the native Central European vegetation, which have dominated in the landscape for the last c. 10,000 years. Stands with an oak and hornbeam dominance occupied lower elevations before human colonization, beech and silver fir-beech forests middle elevations and spruce stands at higher elevations. Only a few remnants of forests, which can be regarded as primeval or with a minimal impact of forest management, have survived in densely populated Central Europe. Examples of the most preserved primeval forests are Rothwald (Austria), Białowieża (Poland, Belorussia), Stužica/Stuzhytsia (Slovakia, Ukraine) and Boubín (Czech Republic). Although these sites are small and isolated, they are local diversity centers for many organisms, mainly for fungi, lichens and bryophytes, refugia for numerous endangered species and some of them have their last localities there. Epiphytic and epixylic lichens are an ideal model group for studies about forests because they sensitively indicate management, continuity, heterogeneity and age of a woodland. Therefore they could help us to answer many important questions about the conservation of natural forests. This thesis comprises several different points of view on lichens in Central European forests and its aim is to join these heterogeneous fields into one...
Epiphytic species of the Lecanora subfusca group in the Czech Republic
Malíček, Jiří ; Palice, Zdeněk (advisor) ; Guttová, Anna (referee)
- 4 - ABSTRACT During the revision of epiphytic species of the Lecanora subfusca group in the Czech Republic, nine taxa have been recorded. L. cinereofusca and L. exspersa are reported for the first time from the country. L. circumborealis has been excluded from the list of Czech lichens. L. cinereofusca and L. horiza could be considered as extinct. L. rugosella and L. subrugosa are regarded as extreme morpholocial forms from L. chlarotera and L. argentata. These morphotypes corelate with ecological conditions: substrate (nutrient enriched bark) and habitat (eutrophisation effect). In case of L. subrugosa, this speculation was confirmed by molecular data (ITS rDNA sequences). Several new secondary metabolites have been discovered during the detailed research of chemical lichen compounds. These substances belonging to terpenoids are taxonomically important and very helpful for distinguishing single species. The abundance of L. allophana and L. chlarotera has decreased during last decades. Contrarily, L. pulicaris expanded slightly. The main reasons of changes in distribution are air pollution and acidification of substrates as the impact of acid rains. The rate of substrate acidification has been shown on example of L. pulicaris. In the past, this lichen predominated on acid-barked porophytes. Nowadays, it...
Epiphytic species of Lecanora subfusca group in the Czech Republic
Malíček, Jiří ; Vondrák, Jan (referee) ; Palice, Zdeněk (advisor)
The main aim of this bachelor work is to summarize knowledges on species of the Lecanora subfusca group growing in the Czech Republic, eventually taxa their occurence may be expected in our area. Only epiphytic and/or epixylic species are included in this study because of a large diversity of the group. Ten taxa have been published from the country. This group is poorly explored in Central Europe because of difficult determination of single species. A comprehensive treatment is lacking in this area. For most taxa of this group only limited information on ecology, distribution, chemistry and taxonomic concepts exists. The present work is reviewing up-to-date knowledge of this group. Historical sources were based mainly on morphological and anatomical data. These were evaluated and excerpted. The bachelor work should serve as a basement for the following diploma thesis.

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