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Succisa pratensis and impacts of herbivores on individual fitness
Janovský, Zdeněk ; Münzbergová, Zuzana (advisor) ; Pergl, Jan (referee)
Zdeněk Janovský Succisa pratensis and impact of herbivores on individual fitness In this master thesis I tried to examine the impact of three herbivore groups on both short- term and long-term fitness of Succisa pratensis individuals. Concretely I studied these three herbivore groups: (i) folivores; (ii) stalk grazers; and (iii) seed predators. The impact of folivores and stalk grazers was studied in a four-year study on repeatedly censused individually marked S. pratensis plants on six sites. The impact of seed predators was studied in a separate experiment. Stalk grazers and seed predators have a direct negative influence on short-term plant fitness. However, the impacts of stalk grazing were offset by affected plants by means of increased long-term flowering probability. On the other hand folivores have a long-term negative effect on plant reproductive effort despite their short-term positive influence on survival and clonal reproduction. Probable explanation of this observed phenomenon could be due to the influence of folivores on reproductive effort of the plants already in the year of their occurrence. The impact of seed predators is very variable, although higher plants suffered from higher proportion of destroyed seeds. A conceptual model of possible impacts of these three herbivore groups on...
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Interactions between plants and soil biota and effect of energetic crops on these interactions
Heděnec, Petr ; Frouz, Jan (advisor) ; Pergl, Jan (referee) ; Mortimer, Simon (referee)
My PhD thesis is focused on study of plant-soil interactions. Chapter 1 is focused on general introduction to the interactions between plants and soil biota in terms of relationships between soil organisms and aboveground biomass as well as root biomass. Chapter 2 is focused on food interaction of Folsomia candida and soil microscopic fungi (Penicillium chrysogenum, Penicillium expansum, Absidia glauca, and Cladosporium herbarum). Fungi were grown separately on Petri dishes or on different litter type (oak, alder and willow) separately as well. Laboratory experiments showed that food preference was more influenced by different litter types than fungal species. In chapter 3 was studied long-term production of hybrid sorrel and its effect on the composition of the soil meso and macrofauna, basal soil respiration, microbial biomass and composition of cultivable fraction of soil microscopic fungi in comparison with oilseed rape and cultural meadow. There was found that long-term production of hybrid sorrel affects the composition of soil fauna, while the microbial activity of the soil was more affected by agriculture practices, especially tillage. In chapter 4 was studied the effect of native (Salix viminialis and Phalaris arudinacea) and introduced (Reynoutria sachalinensis, Silphium perfoliatum and...
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Management of alien plant species in Prague
Fleischhans, Richard ; Pergl, Jan (advisor) ; Görner, Tomáš (referee)
Invasive and alien plants are one of the factors threatening biodiversity. Influence of this factor will become stronger in the future because of climate change. In local or regional areas these species are capable of disturbing material and energetic flows, change properties of environment and affect (often negatively) materials and services provided by ecosystems. This is the reason why invasive species are becoming targets of eradication and other interventions leading towards reducing their numbers and spread in invaded area. Despite these efforts, expansion and number of invasive alien species is growing in the world. Mainly globalization, more intensive traffic through countries and continents drive spreading of plants to new areas.There are not many examples of successfull eradication projects which led to complete removal of alien invasive plants on bigger areas. The majority of successfull removal of these species took place on islands. Fails of these efforts were caused probably by the need of repeating management action over the affected areas several years after. It is necessary to have clear idea since the beginning of the intervention about time frame of intervention and arrange enough money, material and personal capital. The obstacle to succesfull intervention may also be...
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Biotic threats to garden monuments: algae, cyanobacteria and invasive plant species
Pergl, Jan ; Perglová, Irena ; Albrechtová, J. ; Antl, Tomáš ; Abarenkov, K. ; Baldrian, Petr ; Cihlářová, L. ; Klečka, Jan ; Kohout, Petr ; Kvasničková, Jana ; Maršálek, Blahoslav ; Maršálková, Eliška ; Pejchal, Miloš ; Petružálková, M. ; Petřík, Petr ; Pyšek, Petr ; Sádlo, Jiří ; Štefl, Lukáš ; Tedersoo, L. ; Větrovský, T. ; Vlk, Lukáš ; Vojík, Martin ; Vosátka, Miroslav ; Zezulka, Štěpán
Chateau, city parks and gardens are perceived as harmonious parts of the landscape. Unfortunately, even these areas have to face various threats, and they can be a threat to the surrounding environment. The exhibition /catalogue presents a look at the organisms that threaten parks. These threats cover unwelcomed invaders covering invasive plants and small microorganisms in the soil, on facades, statues or in water. On the other hand, some species that are intentionally brought to the parks can be risky not only the gardens themselves but also their surroundings.
Fulltext:  PDF
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Management of native and alien plants in garden monuments
Sádlo, Jiří ; Pergl, Jan ; Pejchal, Miloš ; Perglová, Irena ; Petřík, Petr ; Štefl, Lukáš ; Vojík, Martin
The work covers garden monuments in context of spontaneous nature and the occurrence of non-native plant species. We present the management approaches for selected groups of invasive species. The text was written in the context of fields other than monument care and ecology and nature conservatioin. We offer not a simplified methodological guide with a prepared solution of standard situations. We prefer to formulate the text at a greater distance and show the problems themselves, we offer a way to think about them. The approaches are accompanied with examples. In the text, we show local solutions using case studies.
Plný tet: PDF
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Giant hogweed - negative impact of invasion and means of eradication
Uhlíková, Martina ; Müllerová, Jana (advisor) ; Pergl, Jan (referee)
Giant hogweed - negative impact of invasion and means of eradication Invasions represent in most cases negative aspects of current globalized world. Dispersion of non-native species occurs daily and it is caused by anthropogenic or natural processes. Plant species belong to the best described invasive organisms. An emblematic species of plant invasions in the Czech Republic is giant hogweed, Heracleum mantegazzianum. It is one of the most detailed documented non-native species occurring in this country. Due to its qualities hogweed spreads quickly and establishes large stands, which can negatively influence surroundings and lead to both ecologic end economic damage. Compared to other invasive plant species of the Czech Republic, giant hogweed has also negative effects on human health. Due to these characteristics giant hogweed has been an object of interest of many scientific projects, e.g. Giant Alien, aiming to understand attributes that enable its successful invasion. This thesis attempts to give a summary of attributes enabling succesful penetration of giant hogweed into environment, and alert to its negative impact that influences also human activities. Presented data include properties causing hogweed's successfull spread, and means of its eradication. Major part of thesis is devoted to...
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