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Habitat requirements and predictive distribution modelling of Huperzia selago
Trachtová, Pavla ; Wild, Jan (advisor) ; Douda, Jan (referee)
Studies of the occurrence of montane and boreomontane species in ravines of the sandstone landscape are scarce and the occurrence of these species are explained by the presence of temperature inversion. The question is, which factors limit the occurrence ofthese species in ravines with temperature inversion. The aim of this diploma thesis is to reveal factors that influence the occurrence of Huperzia selago in inverse ravines of sandstone landscape. This work uses a habitat variables recorded directly for populations of H. selago and variables derived from a digital elevation model. These derived variables are also used for creation of two predictive models of geographic distribution of H. selago in the National Park Bohemian Switzerland. When we summarize the most informative variables of predictive models and habitat conditions significantly different from control sites, we get the typical habitat of H. selago. Such sites will likely be found on the rock at the bottom of the valley. Factors that influence the suitability of habitat are: moisture, vegetation type, slope, and distance to the bottom of the valley.
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Habitat requirements of two species Huperzia selago and Lycopodium annotinum in sandstone area of NP Bohemian Switzerland
Trachtová, Pavla ; Hadincová, Věroslava (advisor) ; Adámek, Martin (referee)
Species Huperzia selago and Lycopodium annotinum occur in cold and humid habitats with acid substrate. These are mainly mountain areas in the Czech Republic, but also sand gorges, where the temperature inversion is common. The temperature inversion causes the fact, that temperature conditions in ravines are different from the climatic conditions of surroundings, which causes high rate of species variety among the habitats. In these places, Montane and Boreal species grow in low altitudes and in the proximity of thermophile species. The presence of montane and boreal species in sand ravines is largely influenced by inherence of temperature inversion, which is determined by features of ravine (depth, breadth, orientation) and by weather conditions. Other important agents (excepting microclimatic conditions), which influence the prevalence of these kinds, are microelement availability and the rate of competition. In Czech Republic, both species Huperzia selago and Lycopodium annotinum fall into C3 category, which means that they indicate permanent regression in our nature. In the case of my field survey in the area of the Bohemian Switzerland National Park I confirmed this tendency for species Huperzia selago.
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