National Repository of Grey Literature 4 records found  Search took 0.00 seconds. 
Germination requirements of rare and common plant species of Giant Mountains
Paulů, Andrea ; Münzbergová, Zuzana (advisor) ; Moravcová, Lenka (referee)
For a long time studies were focused on searching optimal conditions of germination of individual species. During the last few years studies have started to search for a relationship between germination and various species characteristics. Most of them, however, use only one temperature during germination tests. Very few studies use more than one temperature during the germination tests. In the last years studies started also to compare germination between rare and common species, but these studies compare just a few species. There are no studies which would compare germination on broader range of species. Aim of this study was to indentify which factors are determing germination of species and to find relationships between germination and characteristics of rare species (n=62). Another aim was to find out differences in germination of pairs (n=24) of closely related rare and common species. To test the germination I have chosen a methodology with several consecutive temperatures. Throughout the time of testing , the seeds were placed either in light or in dark. The dataset was processed by linear regression. The results show that germination requirements of species are determinet by time of flowering, weight of seeds, dispersal mode, species requirements for soil humidity and nutrients and type of...
Predictive distribution modelling of selected bryophyte species in Bohemian Switzerland National Park
Procházková, Martina ; Man, Matěj (advisor) ; Moudrý, Vítězslav (referee)
The aim of this thesis was to create potential distribution models for Dicranum majus (Greater Fork Moss) and Polytrichum alpinum (Alpine Haircap) in Bohemian Switzerland National Park. In the Czech Republic these bryophyte species occur in cold climatic regions typically with higher altitudes. In Bohemian and Saxon Switzerland they can occur in really low altitudes thanks to unique microclimatic conditions of deep inversion ravines. These bryophyte species had low number of occurence records in studied area before the start of my research (4 occurence localities for Dicranum majus, 8 occurence localities for Polytrichum alpinum). Predictive habitat suitability models can be an effective tool for selecting potential new occurence localities, planning field research or management design. During field research I recorded 34 new occurence localities for Dicranum majus and 29 new occurence localities for Polytrichum alpinum in Bohemian Switzerland National Park. I used 8 topographic parameters derived from digital elevation model with 1 m resolution as environmental data. Using these data I created models of potential distribution of the most suitable habitats for both species with algorithms Artificial neural networks (ANN), Generalised linear model (GLM) and Random forest (RF). RF algorithm had the...
Germination requirements of rare and common plant species of Giant Mountains
Paulů, Andrea ; Münzbergová, Zuzana (advisor) ; Moravcová, Lenka (referee)
For a long time studies were focused on searching optimal conditions of germination of individual species. During the last few years studies have started to search for a relationship between germination and various species characteristics. Most of them, however, use only one temperature during germination tests. Very few studies use more than one temperature during the germination tests. In the last years studies started also to compare germination between rare and common species, but these studies compare just a few species. There are no studies which would compare germination on broader range of species. Aim of this study was to indentify which factors are determing germination of species and to find relationships between germination and characteristics of rare species (n=62). Another aim was to find out differences in germination of pairs (n=24) of closely related rare and common species. To test the germination I have chosen a methodology with several consecutive temperatures. Throughout the time of testing , the seeds were placed either in light or in dark. The dataset was processed by linear regression. The results show that germination requirements of species are determinet by time of flowering, weight of seeds, dispersal mode, species requirements for soil humidity and nutrients and type of...
Dynamics of rare and threatened species on local and regional scale- from theory to practice
Lampei Bucharová, Anna ; Münzbergová, Zuzana (advisor) ; Tichý, Lubomír (referee) ; Jiménez, Ares (referee)
To assess the status of a rare plant species, we must first understand the factors that affect the size of populations and their numbers. In this thesis, I study processes affecting plant species prosperity on local scale (paper 1), factors influencing species distribution in landscape and ability of species to colonize new habitats (paper 2) and species traits responsible for gene flow between established populations (paper 3). Since I work with rare plants, I also aim to turn theoretical knowledge into practical recommendations for nature conservation (paper 4) to help effectively preserve rare and endangered species. In the first 3 papers, I work with two rare fern species restricted to serpentine rocks, Asplenium adulterinum and A. cuneifolium, in a study system covering 10 × 10 km. I found that both species are long living (several decades) and in the study region, populations are in a good state and slowly growing. Even very small populations (10 individuals) have quite high chance to survive. In both fern species, I found dispersal limitation, which might be surprising regarding huge production of small spores in ferns (paper 2). The species differ in ploidy and thus, also mating system. A. adulterinum is tetraploid and its main breeding system is intragametophytic selfing. A. cuneifolium is...

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