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Sources and causes of spread of newly introduced plant species
Schmiedlová, Barbora ; Münzbergová, Zuzana (advisor) ; Čuda, Jan (referee)
The bachelor's thesis is written in the form of a literature review and deals with factors that affect the current global spread of plants into new areas, and their possible invasiveness in the new areas. The aim is to verify the hypothesis that one of the main causes of the spread of new plant species (the last 50 years aprox.) to new areas could be climate change. The introductory part of the thesis explains the basic concepts (native versus non-native species, invasive species, temporarily introduced species, etc.) and lists the main factors that affect the global distribution of non-native plant species. The following is a description of the issue of current global change, focusing primarily on climate change and what impact it may have on the spread of plant species. The last part of the work focuses on newly introduced non-native plant species and on the factors that influence their global distribution the most, in comparison with plant species introduced a long time ago (more than 50 years ago). It was found that climate change does have a significant impact on the shift of the area of distribution of newly introduced plant species, especially to extreme areas (higher altitude etc.). Several selected non-native plant species, in which a shift in the range of distribution due to climate...
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Current state of vegetation in the Sázava River floodplain after spring flood in 2006
Klášterková, Hana ; Chuman, Tomáš (advisor) ; Matějček, Tomáš (referee)
In this diploma thesis current state of vegetation cover was analyzed after spring flood in 2006 on the lower section of the Sázava river. Immediately after the flood there were 38 sites with alluvial deposits identified in the floodplain. The differences in species composition and species diversity between sites with alluvial deposits and sites without deposits were analyzed. The data were collected by using phytosociological relevés in pairs i.e. - plot with an alluvial deposit and plot without. There were 86 vascular plant species recorded out of which 10 species were non-native but not invasive species and 7 species were non-native invasive species. Results of this thesis revealed that species composition and diversity of invasive species differ between plots with alluvial deposits and plots without alluvial deposits. Moreover, plots without alluvial deposits host more invasive species. Keywords: vegetation succession, river floodplain, extreme floods, species diversity, plant invasion
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The spread of invasive neophytes in the riparian vegetation of the Lužnice River
Eliášová, Kateřina ; Matějček, Tomáš (advisor) ; Hrdina, Aleš (referee)
This thesis studies the spread of invasive neophytes along the South Bohemian Lužnice River. The literature search deals with plant invasions, floodplains and the area of interest. The riparian vegetation along the Lužnice River was mapped with emphasis on 17 taxons of invasive neophytes. The mapping was realized in four sections that were 3-5 km long. The results are compared with the state ascertained by monitoring in the same location in 2008. The results indicate a general increase of invasions and an intensive spread of Impatiens parviflora since the previous mapping. Generally widespread invasive taxa in the studied area are Impatiens parviflora and Impatiens glandulifera of the herbaceous plants. The occurence of Robinia pseudacacia of the woody plants is also common. Other observed taxa occur only locally or in smaller amounts. Keywords: IAS, riparian vegetation, plant invasion, vegetation mapping, watercourse, vegetation change
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Genetic variation in populations of reed canarygrass, \kur{Phalaris arundinacea} L.
KÁVOVÁ, Tereza
The spread of invasive plant species in natural habitats has become a worldwide problem with negative environmental and economic impacts. An increasing number of invasive organisms are responsible for adverse environmental and economic impacts worldwide, including species extinction, crop failures, reduced water supply, and damage to industrial infrastructures (KERCHER et al., 2007). Phalaris arundinacea L. is widespread throughout the world, except Antarctica and Greenland. Center of diversity of this genus is in the Mediterranean. Members of the genus Phalaris occurs in moist habitats from lower to alpine altitudes (ANDERSON, 1997). Phalaris has a plethora of uses. Its most frequent use is as the root wastewater treatment plants. Phalaris grown as feed for livestock and is also used as an ornamental grass. Phalaris have recently received a lot of attention as a new biomass source for the production of renewable energy in USA. In recent years there has been a massive spread of P. arundinacea across North America (currently occurs in 43 states) and Canada (ZEDLER & KERCHER, 2004). Phalaris represents a significant threat to its original wetland vegetation and is classified as a harmful agens in nine state of U.S. states (LAVERGNE & MOLOFSKY, 2004). It is believed that these aggressive population have European origin.
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Study of allelopathic effects in species of Impatiens genus (Impatiens L.)
KREJČOVÁ, Jana
All three jewelweeds species (Impatiens. L.)contain series of secondary metabolites from category of phenolic substances, e.g. naphthoquinones. This substances belong to allelochemicals, they can to affect germinability and growth of other plants. The extracts from jewelweeds (leaves, roots) and their fractions can to affect negatively germinability and growth of the chosen weed's seeds. Knowledges of allelopathic effects in jewelweeds species on other plants might be of important impact on ecological farming in the implementing of alternative herbicides.
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