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Watermilfoils (Myriophyllum) in the central Europe
Hrdinová, Magdalena ; Trávníček, Pavel (advisor) ; Prančl, Jan (referee)
Genus Myriophyllum L. (watermilfoil) belongs to one of the most species-rich genera within Haloragaceae (Saxifragales). It includes three invasive species, which are of major concern - European M. spicatum L., North American M. heterophyllum MICHX. and South American M. aquaticum (VELL.) VERDC. All of them occur in Central Europe as well as native M. verticillatum L. and M. alterniflorum DC. lacking more significant invasive growth up to now. It is not only its invasivness that makes genus Myriophyllum so fascinating. It also displays extremely high phenotypic plasticity which is accompanied by determination difficulties. Moreover, recent research indicates that Myriophyllum tends to hybridize producing more invasive hybrids than parental taxa. Such traits pose a formidable challenge to scientists to deal with possible future invasive growth of non-indigenous Myriophyllum species in Central Europe. Therefore, thorough study of factors influencing evolution success of plants should be conducted. One of the key factors seems to be polyploidy. Research into polyploidy offers a new approach to watermilfoil issues. Additionally, according to preparatory study all native Central European Myriophyllum species can be easily distinguished by flow cytometry. That enables to study polyploidy in an...
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Distribution and ecology of the turbellarian Dugesia tigrina in the Vltava river and selected Prague brooks and its interactions with native turbellarian species
Sevruková, Natálie ; Mourek, Jan (advisor) ; Hanel, Lubomír (referee)
Key words: (Dugesia tigrina), ecology, bioindication, predation, Vltava, Prague The main goal of my thesis was the research of occurrence and ecology of planarians of the group Ttricladida in the Vltava River and some brooks flowing through the territory of Prague. The emphasis was given on the non-native North American species - Dugesia tigrina. The research can be divided into field surveys of population size and ecological requirements of planarians and a laboratory experiment, in which I have investigated the predation behavior of planarians. During my fieldwork, which took place from August 22th to November 11th 2009, I have found out that the Dugesia tigrina occurs only in the Vltava river, in six of the nine studied localities. During the research it was not found in the studied brooks. It chooses localities with a natural shoreline, deeper ground, rapid water and it lives in company of mainly Dugesia polychroa. It appeared at moderately polluted places. During the predation experiment, which ran from December 17th 2009 to October 20th 2010 at a temperature of 14 řC and triple repetitions in all mutual combinations of five planarian species, intraspecific cannibalism and frequent asexual reproduction of Dugesia tigrina was comfirmed. The experiment showed mainly preying of indigenous...
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Economical impact of invasion IAS
Tyrpekl, Lukáš ; Berchová, Kateřina (advisor) ; Hana, Hana (referee)
The invasion of plants and animals species are considered as one of the main danger for diversity of natural ecosystems worldwide. With destruction of habitats represent the main reason of the current global wave of taxa extinctions. The obviousness of biological invasions are financial costs in different branches connected with their prevention and liquidation.
The main purpose of this master thesis was to evaluate the economic impacts of invasion of the selected invasive species, concretely Grand hogweed (Heracleum mantegazzianum), Himalayan balsam (Impatiens glandulifera), Giant goldenrod and Canadian (Solidago gigantea and canadensis) and also Japanese knotweed, Giant knotweed and Bohemian knotweed (Reynoutria japonica, sachalinensis and × bohemica). As an area of interest was Třeboňsko chosen, where the economic impact of these invasive species based on the results of field investigation was evaluated with in cooperation with an owners of the affected land. Also, ecosystem damage were registered and total financial damage was estimated.
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Vyhodnocení současného stavu populace pajasanu žláznatého (Ailanthus altissima (Miller) Swingle) v Brně
Kovář, Roman
The bachelor thesis on the topic "Evaluation of the present-day state of the population of the Tree of Heaven (Ailanthus altissima (Miller) Swingle) in Brno" is divided into two parts, the theoretical and the practical part. The theoretical part deals with the issue of invasive tree species and its characteristics. The extensive chapter concentrates on the specific kind of the Tree of Heaven (Ailanthus altissima). Furthermore, it describes the area of interest and presents the results of observing the Tree of Heaven by other authors in Brno. The practical part is focused on mapping so far unmapped specimens of this derivative kind in the area of Brno-Černovice, on statistical evaluation of obtained data and finally on comparing the results with other authors.
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Distribution of wild cucumber, Echinocystis lobata Torr. et A. Gray, in chosen rivers in the Czech Republic
ČIHÁKOVÁ, Tereza
The aim of this work was to create an overview of known locations of the invasive lianas Echinocystis lobata (Michx.) Torr. et A. Gray in selected rivers in the Czech Republic with the contribution of my own data from the field survey. The selected flows were the rivers Sázava, Lužnice, Ohře and the stream Mastník. There were 71 places located on these flows and 7 others were found in the surroundings of gardens and cottage area in Kosova Hora.The original location of the species is North America. It extends mainly along watercourses from where it spreads to nearby locations. Štětinec laločnatý is one of the most problematic invasive species in Europe because its vegetation form creates a continuous layer over other species in the lower level and thus prevents the access of light (Dajdok et Kacki, 2009). It is important to monitor its spread and, if possible, adopt measures for its control.
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Population - ecological study of invasive species \kur{Lupinus polyphyllus} in the Bohemian Forest
HURTOVÁ, Jaroslava
Lupinus polyphyllus Lindl. is one of the most dangerous invasive species in the Czech Republic and its increasing occurence is a threat of biodiversity of natural plant communities not only in the Bohemian Forest. Exploration of facts of invasive species problems was worked up. Species spread in area of the National Park Šumava was traced and put in GIS layer with record of habitat features (abundance per population and nature of biotope) that was consequently analysed. Surroundings of the seed germination were found. Influence of the seed germination and seedling survival on the altitude were studied. Enduring areas for management experiments were founded on the three localities in the Bohemian Forest for future research.
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Ecological study of invasive species \kur{Echinops sphaerocephalus} in Blanský les PLA
PŘIBÍKOVÁ, Eva
In this study, digital maps depicting occurrence of invasive species Echinops sphaerocephalus (Asteraceae) in the Blanský les PLA (Protected Landscape Area) and surroundings were created. Localities recorded in last 208 years in the Czech Republic were listed and great globe thistle?s spreading was showed. Germination abilities and growth characteristics of seedlings were also tested. Different management interventions were realized and their effect on great globe thistle regeneration was examined.
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