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Studium problematiky nepůvodních druhů ve vybraném úseku povodí řeky Svratky
Ševčíková, Alice
This thesis deals with the issue of alien species in the selected basin of the river Svratka. The examination of selected vegetation took place near Brno, Tišnov and in Modřice. The studied areas were located on the bank of the river Svratka, on agricultural land near the bank and a few meters from the catchment on uncultivated land. My study of vegetation areas lasted from 2013 to 2015. As monitoring methods I used Zurich-Montpelier phytosociological school. Monitoring was statistically processed by analysis DCA and CCA. Total of 91 kinds of plants were founded in the selected places of the river. The highest ground cover species were Impatiens glandulifera, Plantago major, Amaranthus retroflexus, Chenopodium album, Arrhenatherum elatius, Dactylis glomerata, Urtica dioica, Convolvulus arvensis, Galinsoga parviflora, Elytrigia repens.
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Přirozená obnova pod borovými porosty na PR Kamenný vrch
Šardická, Veronika
The aim of the work is the mapping of actual natural regeneration of tree species in a part of the territory of the Nature Reserve Kamenný vrch (Brno) and next comparison actual natural regeneration with 2012. This mapping continues to work of Martin Šrom who made reseach flat and performed first mapping. Kamenný vrch has been Natural Reserve since 1978. Its area is more than 14 hectars. Primary task of Nature Reserve is protection of Greater Pasque Flower (Pulsatilla grandis) and the rest of the well-preserved natural thermophylic species. These species are non-autochtonous in large part but often there are prime species under non-native species. The aim of the work is the mapping of the natural regeneration under the pine stands (Pinus sylvestris), comparison and evaluation of the results with 2012, tabular and graphical reports and their verbal evaluation.
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Diversity and succession of spontaneous vegetation in urban environment
Rejchrtová, Lucie ; Vojta, Jaroslav (advisor) ; Adámek, Martin (referee)
Urban vegetation is important due to its functions (e.g. aesthetic, spiritual, recreational, hygienic). In the city, vegetation and its succession are influenced by factors such as nature in the same or altered form. Compared to the surrounding landscape, the city's climate is warmer, the urban soil has an increased pH, it is drier, it can contain more nutrients, heavy metals and salt. In the city, human activity, and humans themselves are the main plant breeder and biotope disturbant. As a result of all the above, plants with higher demands on heat, light, alkalinity, nutrients and disturbances occur in the city. These are often alien species, which are much more in the city than in the surrounding landscape due to the more frequent occurrence of early successional stages. The proportion of alien species during succession decreases in favor of the native species. The total number of species (even within each group of species - native species, archeophytes and neophytes) is higher than in the surrounding landscape due to the high diversity of biotopes and the introduction (intentional and unintentional) of species by human activity. Keywords: urban vegetation, succession, diversity, anthropogenic factors, alien species
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The crayfish plague pathogen Aphanomyces astaci in its introduced ranges: vectors, introduction pathways, genetic variation and host-pathogen interactions
Mrugała, Agata ; Petrusek, Adam (advisor) ; Füreder, Leopold (referee) ; Vralstad, Trude (referee)
- ABSTRACT - The crayfish plague pathogen, Aphanomyces astaci, is responsible for substantial declines and local extinctions of native European crayfish populations. As a consequence, the pathogen is now listed among 100 world's worst invasive alien species. The spread of A. astaci is greatly facilitated by its natural hosts, North American crayfish, that thanks to a long co-evolutionary history with the crayfish plague pathogen evolved efficient defence mechanisms. In contrast, European, Australian and Asian crayfish species are highly susceptible to this disease agent. However, progress of A. astaci infection in native European crayfish was observed to differ between distinct pathogen strains, indicating variability in their virulence. Indeed, we demonstrated a relationship between patterns in crayfish immune response and A. astaci virulence in an experimental infection involving the European noble crayfish and three differently virulent crayfish plague strains. The European continent is currently inhabited by at least eight North American crayfish species. The carrier status was confirmed in six of them, including also Orconectes cf. virilis occurring in the Netherlands and the UK. In this country, we detected Aphanomyces astaci presence in some populations of the non-indigenous crayfish species as well...
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Non-indigenous freshwater fish species of the Mediterranean basin of the Balkans
Balog, Štefan ; Vukićová, Jasna (advisor) ; Švátora, Miroslav (referee)
Mediterranean basin of the Balkan Peninsula is one of the hot-spots of biodiversity, with a high diversity of freshwater fishes and high degree of endemism. Introduction of non-native species greatly affects ecosystems and native species of fish. There were many reasons for introductions in the past. Aquaculture, sport fishing and ornamental fish belong to the most important reasons for introduction of non-native fish species. Altogether, 39 species belonging to 12 families were introduced in the Mediterranean basin of the Balkan Peninsula. Most of them belong to the families Cyprinidae and Salmonidae. Introduction of fishes was known since the Roman era. Although the first recorded introduction in this area was in the 13th century, most species were introduced in 20th century. The fishes were introduced from North America, Europe and Asia. Many translocations occurred in this area, too. Translocation is a relocation of particular species within one area. The most widespread introduced species in the Mediterranean basin of the Balkans are common carp (Cyprinus carpio), stone moroko (Pseudorasbora parva), rainbow trout (Onchorhynchus mykiss), mosquitofish (Gambusia holbrooki), goldfish (Carassius auratus) and sunfish (Lepomis gibbosus). Hybridization, competition, pathogen transmission and predation...
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Relationship between species diversity, temperature and productivity for native and non-native plant species
Szostoková, Kateřina ; Šímová, Irena (advisor) ; Hejda, Martin (referee)
Latitudinal gradient of diversity is typically being explained by the three main hypotheses: The Resources Limitation Hypothesis, The Speciation Rate Hypothesis and The Niche Conservatism Hypothesis. In my study I tested basic assumptions of these hypotheses using native and non-native vascular plants obtained from the new database GloNAF (Global Naturalized Alien Flora). I tested an effect of precipitation, NPP, temperature and historical velocity (difference in temperature and precipitation between the Last Glacial Maximum and present) on species richness. Given that the distribution of non-native species is among continents irregular (we can divide them into two groups - Australia with Europe and North America and South America with Africa and Asia), I tested the abovementioned relationships at both - global and continental scale. Species richness of native species increased with NPP, precipitation and temperature and decreased with the difference in temperature. The global distribution of non-native plants increased with precipitation and temperature velocity and decreases with temperature and precipitation velocity, although the results varied for particular continents. Unlike other studies the number of non-native species didn't correlate with the number of native plant species. Concurrently...
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Secondary metabolites, allelopathy and their significance in the invasion of Heracleum mantegazzianum
Jandová, Kateřina ; Dostál, Petr (advisor) ; Frouz, Jan (referee) ; Valterová, Irena (referee)
One theory concerning the invasiveness of exotic plants suggests that they exude allelopathic compounds that are novel in areas being invaded. Here, I tested for allelopathic effects of root exudates of the invasive plant Heracleum mantegazzianum (giant hogweed) in a series of experiments both in vitro and in the garden, and compared them with effects of its native congener H. sphondylium (common hogweed) and two less related native species. Moreover, I addressed intraspecific variability of allelopathy by comparing effects of 41 different maternal lines of H. mantegazzianum sampled from several areas and populations within the Czech Republic. Not only the effects, but also the identity of allelopathic compounds was investigated. In order to test also for the interaction of allelochemicals with soil microorganisms, I analysed the composition of soil microbial communities expressed as phospholipid and neutral lipid fatty acids (PLFA and NLFA, respectively) together with nutrient conditions and light availability at invaded sites in the Czech Republic. The results show that H. mantegazzianum is able to exert phytotoxic effects in vitro as well as in the garden experiment; however, its effects did not differ from the inhibition caused by the native species tested. Variation partitioning among areas,...
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Problems of hybrids and non-native species of falconry birds of prey (Falconiformes)
RICHTROVÁ, Zuzana
There have been more and more discussions of the influence of falconry on wild populations of birds of prey in recent years. Where the main topic previously dealt with stealing young birds from nests, today's concerns revolve around interspecific hybrids and non-native species. This thesis therefore focuses on these issues and attempts at collecting available information. The main finding is that only few serious researches have been carried out on this topic so nobody can make a conclusion that would subsequently lead to practical interventions. The available sources clearly show that non-native species are most likely not to pose any risk to nature. In contrast, the information on hybrids was very inconsistent and often diverged. It is probable that hybrids have some influence in nature; but to determine its severity and whether or not intervention is required, we need to carry out a detailed scientific study. IAF (International Association for Falconry) recommends a number of measures that seem to be sufficient at the time and they include: - ban on arbitrary discharge of hybrids and non-native species into the wild - ban on free-hacking while training these birds - requirement to use telemetry in training - requirement to use maximum effort in order to trace these birds in case they get lost - imprinting of young hybrids in species that is not found in nature in the given area Improvement should mainly be made in the registration of birds of prey. At this point and in most countries, it does not allow you to trace the birds' parents reliably and, as a consequence, one cannot unambiguously determine whether the bird in question is a hybrid or pure species.
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Prediction of invasive marbled crayfish (Procambarus fallax f. virginalis) global spread
Nováková, Pavla ; Patoka, Jiří (advisor) ; Antonín, Antonín (referee)
Biological invasions are currently a global problem. They often cause a loss of biodiversity and severely disrupt the balance of entire ecosystems. One of the most dangerous among the many species of crayfish known to be invasive is the marbled crayfish or Marmorkrebs (Procambarus fallax f. virginalis Martin et al., 2010).
The marbled crayfish is a major ornamental crayfish species. It is a known vector of infectious crayfish plague, which is lethal for crayfish species of non-North American origin. Marbled crayfish is also very tolerant to different water temperatures. The most important feature making it an especially dangerous invasive species, is the way of its reproduction. Marbled crayfish reproduces via apomictic parthenogenesis. Therefore, only females are able to reproduce and males of this taxon has not been recorded. This crayfish is characterised by a very quick maturation and extremely rapid growth.
Even though some established populations of this taxon in the wild have already been recorded, and probability of the establishment in selected regions was evaluated, no predictions for expansion on a global scale have been conducted.
The program CLIMATCH was used in this thesis to match the climate conditions between the source area (distribution of established populations of marbled crayfish in the wild) and target areas (all continents excluding Antarctica) based on temperatures during the coldest and warmest quarters of the year.
The results showed that marbled crayfish can probably survive and reproduce in even colder regions of the temperate zone. The presented findings additionally indicate that temperate zones contain slightly higher potentially suitable regions than in the case of tropics. There are temperature conditions most suitable for the survival and reproduction of the marbled crayfish within Europe in comparison of the rest of the world; and the least favourable temperature conditions are within Australia.
The marbled crayfish introduction and ability to survive and reproduce in the wild is a potential threat to native biota and entire ecosystems on all continents assessed. Therefore, it is strongly recommended that the breeding of and the pet trade with this crayfish should be regulated by policymakers and wildlife managers by improvement of legislative restrictions (such as in the EU) and intensive future education of general public. It is obvious that the monitoring of invasive crayfish species might be continuous. Nevertheless, the most important step is to make producers and hobbyists aware of the risks related with marbled crayfish.
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Invasions of phytophagous insects in Central Europe
Rejmanová, Aneta ; Špryňar, Pavel (advisor) ; Koubek, Tomáš (referee)
This Bachelor thesis is meant as a literature search concerned with invasions of phytophagous insects in Central Europe (mainly in the Czech Republic). I have summarized the findings from Czech and foreign studies dealing with this issue. Biological invasions are now a significant phenomenon. About 400 species of non-native insects occur in the Czech Republic, of which about half are phytophagous insects. In my Bachelor thesis I dealt with terminology that related to this subjekt, some more general regularities in the relationship of plants and insects, the primary areas of non-native insects, their pathways and their impact. I also chose few well-known representatives for better ilustration and I trying to find out, which plants non-native insect attacks the most. Key words: alien insects, phytophagous, plant, invasive
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