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Evolutionary processes underlying plant diversification in the tropical Andean highlands
Aparicio Vásquez, Diana Libeth ; Sklenář, Petr (advisor) ; Hughes, Colin (referee) ; Šmarda, Petr (referee)
The highlands in the northern Andes, which are known as the páramo, are recognized worldwide for their unique and species-rich flora. Many páramo plant groups underwent radiations, which have been shown to be very recent and outstandingly fast. These radiations have usually been linked to (1) the uplift of the northern Andes, which provided new ecological opportunities in the highlands that originated in this process, (2) Quaternary climate change that produced range shifts of the páramo, resulting in periods of páramo contraction and isolation, during cold periods, and periods of páramo expansion and connection, during warm periods (3) the Andean physiographical and ecological heterogeneity, which provides extent oppornuties for isolation and for ecological divergence. In spite of increasing research efforts to understand the evolution of the páramo flora, the actual processes underlying species diversification remain unclear. The main aim of this thesis is to contribute to the understanding of these processes. We use three different approaches in two different study systems: (1) A population genetics approach, which remains rare among páramo plant studies, focuses on three páramo Lupinus species (Lupinus alopecuroides, L. nubigenus, L. microphyllus). These species belong to one of the best...
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Evolutionary processes underlying plant diversification in the tropical Andean highlands
Aparicio Vásquez, Diana Libeth ; Sklenář, Petr (advisor) ; Hughes, Colin (referee) ; Šmarda, Petr (referee)
The highlands in the northern Andes, which are known as the páramo, are recognized worldwide for their unique and species-rich flora. Many páramo plant groups underwent radiations, which have been shown to be very recent and outstandingly fast. These radiations have usually been linked to (1) the uplift of the northern Andes, which provided new ecological opportunities in the highlands that originated in this process, (2) Quaternary climate change that produced range shifts of the páramo, resulting in periods of páramo contraction and isolation, during cold periods, and periods of páramo expansion and connection, during warm periods (3) the Andean physiographical and ecological heterogeneity, which provides extent oppornuties for isolation and for ecological divergence. In spite of increasing research efforts to understand the evolution of the páramo flora, the actual processes underlying species diversification remain unclear. The main aim of this thesis is to contribute to the understanding of these processes. We use three different approaches in two different study systems: (1) A population genetics approach, which remains rare among páramo plant studies, focuses on three páramo Lupinus species (Lupinus alopecuroides, L. nubigenus, L. microphyllus). These species belong to one of the best...
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Antropogenní vliv na biodiverzitu v komplexu Páramos de Santurban (Kolumbie)
Aparicio Vásquez, Diana Libeth ; Sklenář, Petr (advisor) ; Kovář, Pavel (referee)
Paramo is the name of the region encountered in the upper belt (3 000m - 4 800m) of the Andean mountain ridges from Venezuela to the North of Peru. Paramo ecosystem occupies only 2% of the area of those countries. Nevertheless, paramo flora is the richest high mountain flora of the world (over 3500 species, 60% of endemism). High mountain region of the Northern Andes were almost uninhabited until the arrival of the Conquistadores. At the time of the conquest, livestock and new crops were introduced to the Andean ecosystems. Since that time, paramo has been used mainly for extensive cattle grazing and cultivation of potatoes and onions. During the last three centuries an abrupt intensification of the agricultural practices has occurred. The main aim of this study is to investigate the effects of human intervention, by mean of farming, on species diversity of the paramo vegetation. The study area was selected in the paramo belt of Santurban, Colombian Eastern Cordillera. Ordination techniques were applied to analyze the relation between plant species composition, environmental variables and management variables. We found plant species diversity is influenced by cattle grazing and cropping, but the vegetation changes are mainly determined by the altitudinal gradient. Intensity of human impact is also...
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Comparative anatomy of genus Lasiocephalus - from tropical mountain forest to páramo
Ježková, Barbora ; Soukup, Aleš (advisor) ; Lhotáková, Zuzana (referee)
South American genus Lasiocephalus colonized high altitudes of the tropical Andes, the so called páramo, from lower elevations of the Andean forest. Páramo is a specific high-altitude environment characterised by pronounced diurnal changes in temperature, growing season over the entire year, low average temperatures, generally high humidity, and intense solar radiation. These specific environmental conditions are reflected by anatomical characters of the species. Given the known phylogeny of the group it was possible to observe anatomical adaptations along steep gradient of environmental conditions from forest to páramo. The hypothesis about adaptive changes that occurred during the colonization of the páramo habitats was confirmed. Observed characteristics were, for example, leaf area and thickness, epidermal cells cuticle and cell wall thickness, epidermal cells lumen height, ratio of palisade and spongy parenchyma, stomatal area, stomata length and width, stomata pore length and sieve elements average area. Results suggest that the anatomy of the plants reflect the environmental conditions of the habitats rather than the species phylogeny.
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Anatomy and functional ecology of tropical alpine plants in South America
Gorčicová, Barbora ; Sklenář, Petr (advisor) ; Stančík, Daniel (referee)
The bachelor thesis discusses the plants in the páramo. The first part describes unique environment located at high altitudes of the tropical South America, the páramo. The uniqueness of the environment is caused by several basic conditions. The most important ones are significant daily temperature fluctuations, tropical climate stability during the whole year and high altitude. Anatomy of adapted plants, discussed in the second part of this work, conform to the extreme conditions. There are specific páramo life forms thanks to the uniqueness of the environment. The leaf structure and the vascular system of the plants are significantly modified in terms of anatomy. Although there are quite specific (and therefore interesting) life forms in the páramo, the current knowledge of the plant anatomy is minimal. The last part of the thesis suggests the questions for my future master thesis, which will contribute to better understanding of this underexplored topic.
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Financial analysis of PARAMO, a.s.
Vondruška, Jakub ; Marek, Petr (advisor) ; Dufková, Eva (referee)
The main topic of the bachelor thesis contains in financial analysis of limited company PARAMO. Firstly, financial analysis methods are defined. Then, development of this company is evaluated by means of horizontal and vertical analysis in years 2005-2009. Consequently, ratio analysis of selected indicators follows. And in the conclusion, spatial comparisons of selected financial indicators with foreign companies are realized.
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