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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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