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Meaning of macroecological patterns and indices: mutual links, taxon invariance and successional sequences of assemblages
Pacák, Robert ; Šizling, Arnošt Leoš (advisor) ; Lepš, Jan (referee)
This diplmoma thesis aims to answer three different questions. First aim of this thesis was to analyze measures of alfa and gama diversity based on Hill numbers and find out, if these measures fullfill the weak principle of taxonomic invariance. In other words, my aim was to proove, independetly of used order of diversity, alfa and gama diversity will be always lower for higher taxonomic groups (eg. genus), than for lower taxonoic groups (eg. species). For this purpose, I used direct mathematical proof, and I showed, that equations for alfa and gama diversity are both taxonomic invariant. Moreover, I analyzed one specific measure of beta diversity as well. I showed, that beta diversity of order zero may increase or decrease in taxonomic switch. Second aim of this thesis was to examine influence of abundances on visualising of preferences of species for different enviromental factors. For thi purpose I desinged new methodology based on well-known RANK plots. This methodology should filter the influence of irregular data collectioning. In other words, this methodology should consider the case, that values of enviromental factors in data are not uniform, which may result into apparent preferences of species. Moreover, this methodology is desinged to take into considerations abundances of species as...
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The role of biotic interactions in population biology of meadow plants
Janovský, Zdeněk ; Herben, Tomáš (advisor) ; Lepš, Jan (referee) ; Ehrlen, Johan (referee)
In present thesis, I treat the topic of impacts of plant-animal interactions, namely herbivory and pollination, on plant life cycle and lifetime fitness. First, I identify the components of the impact of plant-animal interactions: i) interaction frequency; ii) per-interaction effect; iii) sensitivity of the plant's life cycle to the changes in vital rate impacted by the animals. Furthermore, I also classify other causes changing the outcome of a plant-animal interaction into two categories: i) plant's traits; ii) plant's environment. A review of extant literature on the topic revealed that especially the role of plant's environment in changing the outcome of plant-animal interactions is largely understudied and I attempt to reduce this gap in knowledge in the five detailed studies encompassed in this thesis. The detailed studies focus on a model system of Central European wet grasslands and especially on three species typical to it: Succisa pratensis, Achillea millefolium and A. ptarmica. The first two studies examine the effects of environment on frequency of plant- animal interactions. The next two studies are more integrative, one focusing on the impacts of different herbivore groups on the complete life cycle and the other on interaction of herbivory and pollination on plant lifetime fitness....
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Local adaptation of the rare herb Aster amellus in fragmented landscape
Raabová, Jana ; Münzbergová, Zuzana (advisor) ; Lepš, Jan (referee) ; Matthies, Diethart (referee)
This thesis aimed to test specific hypothesis conceming habitat differentiation, local adaptationand outbreedingdepressionof the rare herb of dry calcareous grasslands,lsler amellus. Chapter I examined habitat requirementsof diploid and hexaploid A. amellus and their role in segregationof the two cýotypes in the Czech Republic. I chose three diploid and six hexaploid populations belonging to two habitat types (with low and high productivity). To test for differences in fundamental niche between the two cýobpes' I analysedhabitatcharacteristicsof sites occupiedby each cýotype and usedreciprocalhansplantexperiments.Then,I testedtheeffectsofhabitattype,ploidy level andpopulationoforigin on plantperformancein theexperiments. Sites of diploid and hexaploid populationsdiffered significantly in vegetation and soil propertiesbut much overlap existed in habitat characteristicsof the two cytotypes. Diploids had overall higher flowering percentage than hexaploids, suggesting differences between the two cytotypes. However, plants frorn sites with low productivity also flowered more than plants from sites with high productivity. Moreover, the largest differences in survival, leaf length and flowering were found amongplants from different populations.This suggeststhatoverall performanceoťl. amellus differs more...
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Patterns and processes in spatial distribution of plant species across scales
Macek, Martin ; Wild, Jan (advisor) ; Lepš, Jan (referee) ; Zimmermann, Niklaus E. (referee)
In this thesis, I aimed to identify factors shaping plant distribution at different spatial scales, correlate them with environmental heterogeneity, identify causal processes and test general hypothesis on the nature of response curve shapes and species richness patterns. General review of the topic is introduced in the first chapter, followed by five chapters presenting three already published studies and two manuscripts. The first study deals with processes responsible for creation of fine-scaled spatial pattern of spruce seedlings and saplings, emerging after bark-beetle disturbance in mountain spruce forest. Aggregated pattern, replicating previous generation of spruce trees, emerges in consequence to microsite-dependent mortality, as was surveyed through repeated monitoring of the fate of individual seedlings. The second study explores spatial variability in forest understory temperatures at the landscape scale and its relevance for understory plant distribution. As the main source of variability in understory communities we identified seasonal maximum temperatures. Using GIS modelling approach, we created spatially continuous prediction, which outperformed state-of-art climatic grids used currently by ecologists. The third study on the shape of species responses along elevational gradients...
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Local adaptation of the rare herb Aster amellus in fragmented landscape
Raabová, Jana ; Münzbergová, Zuzana (advisor) ; Lepš, Jan (referee) ; Matthies, Diethart (referee)
This thesis aimed to test specific hypothesis conceming habitat differentiation, local adaptationand outbreedingdepressionof the rare herb of dry calcareous grasslands,lsler amellus. Chapter I examined habitat requirementsof diploid and hexaploid A. amellus and their role in segregationof the two cýotypes in the Czech Republic. I chose three diploid and six hexaploid populations belonging to two habitat types (with low and high productivity). To test for differences in fundamental niche between the two cýobpes' I analysedhabitatcharacteristicsof sites occupiedby each cýotype and usedreciprocalhansplantexperiments.Then,I testedtheeffectsofhabitattype,ploidy level andpopulationoforigin on plantperformancein theexperiments. Sites of diploid and hexaploid populationsdiffered significantly in vegetation and soil propertiesbut much overlap existed in habitat characteristicsof the two cytotypes. Diploids had overall higher flowering percentage than hexaploids, suggesting differences between the two cytotypes. However, plants frorn sites with low productivity also flowered more than plants from sites with high productivity. Moreover, the largest differences in survival, leaf length and flowering were found amongplants from different populations.This suggeststhatoverall performanceoťl. amellus differs more...
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Meaning of macroecological patterns and indices: mutual links, taxon invariance and successional sequences of assemblages
Pacák, Robert ; Šizling, Arnošt Leoš (advisor) ; Lepš, Jan (referee)
This diplmoma thesis aims to answer three different questions. First aim of this thesis was to analyze measures of alfa and gama diversity based on Hill numbers and find out, if these measures fullfill the weak principle of taxonomic invariance. In other words, my aim was to proove, independetly of used order of diversity, alfa and gama diversity will be always lower for higher taxonomic groups (eg. genus), than for lower taxonoic groups (eg. species). For this purpose, I used direct mathematical proof, and I showed, that equations for alfa and gama diversity are both taxonomic invariant. Moreover, I analyzed one specific measure of beta diversity as well. I showed, that beta diversity of order zero may increase or decrease in taxonomic switch. Second aim of this thesis was to examine influence of abundances on visualising of preferences of species for different enviromental factors. For thi purpose I desinged new methodology based on well-known RANK plots. This methodology should filter the influence of irregular data collectioning. In other words, this methodology should consider the case, that values of enviromental factors in data are not uniform, which may result into apparent preferences of species. Moreover, this methodology is desinged to take into considerations abundances of species as...
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The role of biotic interactions in population biology of meadow plants
Janovský, Zdeněk ; Herben, Tomáš (advisor) ; Lepš, Jan (referee) ; Ehrlen, Johan (referee)
In present thesis, I treat the topic of impacts of plant-animal interactions, namely herbivory and pollination, on plant life cycle and lifetime fitness. First, I identify the components of the impact of plant-animal interactions: i) interaction frequency; ii) per-interaction effect; iii) sensitivity of the plant's life cycle to the changes in vital rate impacted by the animals. Furthermore, I also classify other causes changing the outcome of a plant-animal interaction into two categories: i) plant's traits; ii) plant's environment. A review of extant literature on the topic revealed that especially the role of plant's environment in changing the outcome of plant-animal interactions is largely understudied and I attempt to reduce this gap in knowledge in the five detailed studies encompassed in this thesis. The detailed studies focus on a model system of Central European wet grasslands and especially on three species typical to it: Succisa pratensis, Achillea millefolium and A. ptarmica. The first two studies examine the effects of environment on frequency of plant- animal interactions. The next two studies are more integrative, one focusing on the impacts of different herbivore groups on the complete life cycle and the other on interaction of herbivory and pollination on plant lifetime fitness....
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Mechanisms of species-energy relationships across spatial scales
Šímová, Irena ; Storch, David (advisor) ; Kühn, Ingolf (referee) ; Lepš, Jan (referee)
Explaining spatial variation of species richness is a central goal of ecology. Recently it has been shown that the number of species is related to energy availability. There are two major categories of hypotheses concerning possible processes behind this relationship: i) hypotheses based on an assumption that the total number of species at given site is limited by the total amount of resources, and ii) hypotheses assuming that evolutionary and historical processes are mainly responsible for the current species richness patterns. We tested possible explanations concerning both resource limitation and evolutionary history using datasets of herbaceous plants, trees and dragonflies, varying in their scale and extent. Within local communities of herbaceous plants, the number of species was influenced by the total amount of available resources (productivity), through its effect on the total number of individuals and the intensity of interspecific competition. However, the role of resource limitation was not strong, and the form of the resulting species-productivity relationship was affected by habitat heterogeneity acting independently of productivity. Historical processes affecting the size of species pool appeared also as important at this scale (Chapter 1). Within local communities of trees...
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Macroecology of European invertebrates:temporal and spatial patterns extracted from heterogeneous data
Keil, Petr ; Storch, David (advisor) ; Lepš, Jan (referee) ; Kindlmann, Pavel (referee)
Univerzita Karlova v Praze Přírodovědecká fakulta Katedra ekologie Makroekologie evropských bezobratlých: časové a prostorové patrnosti dobývané z heterogenních dat Autoreferát dizertační práce Petr Keil Školitel: Doc. David Storch, Ph.D. Praha 2010 Charles University in Prague Faculty of Science Department of Ecology Macroecology of European invertebrates: temporal and spatial patterns extracted from heterogeneous data Ph.D. thesis - summary Petr Keil Supervisor: Doc. David Storch, Ph.D. Prague 2010 SOUHRN Dizertační práce obsahuje pět kapitol. První čtyři kapitoly jsou věnovány několika aspektům makroekologie evropského hmyzu, jako jsou geografické a časové patrnosti druhového bohatsví. Pátá kapitola zkoumá některé makroekologické charakteristiky populační dynamiky v rámci neutrální teorie biodiverzity. Dizertace je opatřena úvodem, který se věnuje zejména metodickým problémům společným pro většinu kapitol. V Kapitolách I a II jsem se zabýval rozmístěním druhového bohatství pestřenek (Insecta: Diptera: Syrphidae) a vážek (Insecta: Odonata) napříč Evropou. Obě práce ukazují absenci jednoduchého poklesu druhového bohatství od jihu k severu. Druhově nejbohatší jsou horské oblasti kolem Středozemního moře, od kterých směrem na jih a na sever diverzita klesá. V obou případech se jako důležité proměnné...
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