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Mountains as islands
Kačabová, Petra ; Storch, David (advisor) ; Ferenc, Michal (referee)
In this paper I deal with island biogeography and its applicability to isolated mountaintops, as an ecological equivalent of true islands. I discuss both true and mountain islands regarding their origin and the influence of long-term climate evolution on Earth. I underline some features of mountain islands, resulting from their topography and the dissimilarities of both types of island barriers. I find that mountain and true island communities might or might not have a number of species in a state of equilibrium, caused by balance between species immigration on island and their extinction. If the number of species on island is not in equilibrium, species extinction is not balanced by species immigration. I consider patterns of island communities, mainly nestedness, which has been frequently studied on mountain, as well as true islands. I discuss distribution patterns concerning invertebrates. And finally, I concentrate on recent methods of moutain island research and discuss mountain island isolation issues in terms of global warming.
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Methods used to study the effects of grazing on vegetation
Hyklová, Lucie ; Münzbergová, Zuzana (advisor) ; Šlechtová, Anna (referee)
Calcareous grasslands are one of the most diverse habitats of Northern and Central Europe. Most of the calcareous grasslands were created by human agricultural activities and therefore they need some kind of management for their long-lasting maintenance. These habitats have been vanishing during last few decades and that's why there were many experiments provided all around the world to examine possible ways of their restoration and preservation. Grazing of livestock has been a traditional management in many places and is often being investigated nowadays. The aim of this work is to search and compare methods that are used to experimentally study the effects of grazing on vegetation. These experiments use different methods although they usually have the same goal - high species richness. Most of these studies are from Great Britain, Germany and states of Northern Europe. Average length of the experiment is seven years. Key words: grassland, grazing, management, restoration, methods, species richness
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Factors affecting dragonfly species composition in newly created pools and assessment of invertebrate predation on pools zooplankton
Dobiáš, Jakub ; Černý, Martin (advisor) ; Harabiš, Filip (referee)
To identify and quantify the influence of physico-chemical, biotic and geographic factors on the population of dragonflies (Odonata) is an essential tool for research of their ecology. The aim of this study was to 1) assess how these factors influence species richness, diversity and spatial distribution of dragonflies in 42 newly constructed or renewed pools located in the Kokořínsko Protected Landscape Area, which is characterized by two valleys of Liběchovka and Pšovka creeks, low human impact, and a great diversity of small water bodies and 2) use laboratory experiments in order to estimate the relationship between large predatory invertebrates of these pools (Aeshna cyanea, Coenagrion puella, Chaoborus crystallinus and Notonecta glauca) and their common prey (Daphnia curvirostris) in an artificial environment with or without aquatic macrophytes. The pools were monitored and sampled between years 2005 and 2006. In total, 23 dragonflies species were found inhabiting these lentic habitats, comprising 11 species belonging to the suborder Zygoptera and 12 species belonging to the suborder Anisoptera, including a rare species Sympetrum depressiusculum (larvae). Most variability in the dragonfly species richness was explained by the size of the water surface area, followed by the location of the pools (inside...
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On the Nothernmost and Southernmost Limits of European Land Snail Spatial Ranges
Křepelová, Lucie ; Juřičková, Lucie (advisor) ; Horsák, Michal (referee)
The aim of this work was to evaluate the limits of ranges of European land snail species along the north-south gradient. To work out the document it was necessary to prepare the set of digitalized maps, that enabled to create the database of ranges of the individual land snails species. Based on obtained data I tried to identify places where the northern and southern borders of species ranges are the most frequent. The landsnails' ranges are affected not only by particular life requirements of the individual species (potential limits), but also by other conditions, especially climatic, geographical and historical (truncated limits). In this work I focused on their differentiation. Above mentioned process also enabled me to track the north- south changes in species richness of the landsnails taking into consideration the truncated and potential limits. The most important natural barriers constraining that numerous of species cannot naturally widespread from the south to the north are the Scandinavian Mountains, the Alpes and the Carpathians and suprisingly also southern borders of german and polish lowlands. On the other hand, spreading of the species form the north to the south is limited only by the Alpes. I also tried to distinguish the group of species whose ranges are not influenced by these...
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Phytoplankton of the Tatra lakes: factors influencing taxonomic composition and biomass
Červenková, Lenka ; Nedbalová, Linda (advisor) ; Štefková, Elena (referee)
The aim of this diploma thesis was to describe species composition and biomass of phytoplankton in the Tatra Mountains lakes (Slovakia, Poland) and environmental factors influencing them. The surface layer of 89 lakes was sampled in September 2004. Flagellates from Chrysophyta, Dinophyta and Cryptophyta most frequently dominated the phytoplankton biomass. Lake in the same valley usually differed in their dominant taxonomic group as a result of different lake morphometry, catchment type and detailed geological structure. Based on the level of phytoplankton biovolume, the majority of lakes were ultraoligotrophic and oligotrophic, however, mesotrophic and even eutrophic conditions were recorded in some forest and meadow lakes. An allometric relationship between phytoplankton biomass and chlorophyll a was revealed. Specific chlorophyll content did not differ among taxonomic groups. Altogether 233 species were determined, the most diverse group were Chlorophyta. Species richness of lake was 3-46 and it was negatively correlated with altitude and positively correlated with lake area. The majority of species were rare both in term of biomass and number of lakes occupied by a particular species. Average local species biomass was positively correlated with regional distribution. The similarity of species...
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Trophic relationships between insectivorous birds and insect in Papua New Guinea
TVARDÍKOVÁ, Kateřina
The thesis describes diversity of birds along a complete altitudinal gradient and in forest fragments in lowlands of Papua New Guinea. It focuses separately on the diversity of different feeding guilds, and discusses their links to habitat and food resources. More specifically, it focuses on forest insectivorous birds, their predation pressure on arthropods, feeding specializations and preferences, and some of the ways how insectivores search for food.
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Vegetation succession in old fields at broad landscape scales
JÍROVÁ, Alena
This thesis is focused on succession in old fields in Central Europe. Repeated sampling, analysis of surrounding vegetation and soil measurements were conducted in the Bohemian Karst Landscape protected area. Samples from the Doupovské hory Mountains and the rest of the Czech Republic were added to discover basic principles of old field succession at the larger scale of landscapes.
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Diversity and ecology of arboreal ant communities in a tropical lowland forest
KLIMEŠ, Petr
The thesis focuses on the study of arboreal ant communities in a highly diverse tropical rainforest in Papua New Guinea. In the first study of its kind, whole patches of forest were sampled extensively for ants foraging and nesting in tree trunks and canopies. An extraordinary amount of material collected from 684 felled trees and 260 bait stations in plots of primary and secondary forest was used to study the mechanisms structuring the diversity and species coexistence of this ecologically important insect group at the local scale. The first chapter addresses the question "Why are ant communities more species rich in primary than in secondary forests?" and explores the main environmental traits that influence their diversity in tropical trees. The second chapter compares the community diversity and composition and nesting preferences of ant species between both forest types. The final third chapter introduces a novel method, involving large-scale manipulation of ant communities that could serve as a template for future studies focused on complex tropical food-webs of canopy arthropods and plants. In summary, the results of the thesis highlight the importance of primary vegetation in conserving the diversity of native ant communities and the relevance of nesting microhabitats and their turnover between trees, rather than tree taxonomic diversity, for sustaining the diverse arboreal fauna in tropical forests.
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The algae of water basins i Novohradské hory
PLOCOVÁ, Alena
This thesis deals with six ponds, artificial snall lakes, (Mlýnský, Huťský, Pohořský, Uhlišťský rybník, Zlatá Ktiš a Kapelung) in the Novohradské mountains. They were studied at the interval of years 2004-2006. The basic hydrochemistries and variety of species of planktonic Algae and Cyanobacteria were analysed there. The volume of NH4-N was the highest in Mlýnský pond (20-76 ?g/l), which proves for a recent organic pollution. In other cases the rate was in range of 13-53 ?g/l. The most of NO2-N was again found in Mlýnský pond where its rate reached up to 420 ?g/l. The total amount of t-P was of the same rate in all the sites. It differed only slightly- 58-91 ?g/l. From the hydrochemical data follows that the most nutrients loaded is Mlýnský pond and the cleanest is Pohořský one The transparency (Seccki depth) of all the localities is also high (76-200 cm). It can be compared to the lakes of the Bavarian Forrest and the Bohemia Forest (Šumava). The proportion of N/P is usually between 7,0-29,8 (Chart 11), which shows evidence of limiting P (the most common limiting factor for phytoplankton in fresh waters). The total amount of found taxa (98) is comparable to e.g. lakes of the Bohemia Forest (260), this ara is however more explored. The largest amount of species is at Huťský pond (38) and the smallest one is at Uhlišťský pond (17). As a new species for the the Czech Republik was found Staurastrum arctiscon and Phaeospaera gelatinosa, than another interesting discovery is Vacuolaria penardii and Chloromonas nivalis (Scotiella nivalis). Also Dicranochaete sp. and Paulinella chromatophora are noticeable. The ponds of the Novohradské mountains are from the point ob view of hydrochemistry view unigue habitats. They make for refugium oligotrophic, rare and interesting species of Cyanobacteria and Algea and that is why they deserve proper protection.
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