National Repository of Grey Literature 26 records found  previous11 - 20next  jump to record: Search took 0.01 seconds. 
Dispersal of the large pine weevil, Hylobius abietis, at various stages of the life cycle
Doležal, Petr ; Davídková, Markéta
The report summarizes information on flight abilities of the large pine weevil and their changes during growing season. Laboratory experiments on flight mills were confirmed by a field capture-mark-recapture experiment.
Spatial activity of birds and methods of its continuous monitoring
Havelka, Jan ; Sedláček, Ondřej (advisor) ; Kauzál, Ondřej (referee)
The aim of this work was to collect current knowledge of avian spatial aktivity focusing to its internal structure, using modern telemetry devices which allows continuous monitoring of small animal species. In the light of these new methods, avian home ranges seem to be more dynamic structures, changing during diurnal and nocturnal acitvities, breeding cycle, age, sex and social statut of a bird. Thanks to detailed radiotelemetry we can observe even secretive animal behaviour and its characteristics in three dimensions. Continual monitoring allows us to study migration in a detailed way, its influence to other parts of their annual cycle and to asses migration connectivity. In future these new information should be used for targeted conservation of endangered species.
Neglected aspects of bark beetle (Coleoptera: Scolytinae) ecophysiology
DAVÍDKOVÁ, Markéta
The thesis describes several unknown aspects of the spruce bark beetle, Ips typographus (L.), and the double-spined bark beetle, Ips duplicatus (Sahlberg.), life-cycles and ecophysiology. The first study focuses on I. typographus and its dispersal under epidemic conditions in the National park Šumava and introduces a novel method of fluorescent marking and detection of captured specimens. The second study is focused on ability of I. typographus to establish so-called sister-broods, i.e. re-emergence of females that are capable to continue egg laying without a need to mate again. The importance of sister-broods becomes apparent mainly in recent hot and dry vegetation seasons, which is demonstrated by a comparison of recent and historical data. The third study focuses on temperature-dependent development of I. duplicatus under laboratory conditions by the means of sandwich method. Altogether, the studies underline practical importance of ecophysiological studies on bark beetles as one of the tools for their effective management.
Conservation genetics of grey wolf and snow leopard: effect of landscape attributes to the population structure
Benešová, Markéta ; Hulva, Pavel (advisor) ; Kreisinger, Jakub (referee)
Landscape genetic approaches allow to study effects of landscape to population microevolution. Landscape can influence gene flow even in large carnivores with good dispersal ability. Understanding the influence of landscape to the gene flow between populations is crucial for species conservation, especially in the species with low population densities. Aim of the study was to describe genetic structure of the grey wolf (Canis lupus) and snow leopard (Panthera uncia) in selected areas and to determine the influence of the landscape features on observed structure. Non-invasive genetic samples of snow leopard from Nepal were analysed, as well as invasive and non-invasive samples of grey wolf from Central Europe. Population structure was determined a posteriori using Bayesian clustering approaches that integrate genetic and geographical data, and compared to landscape connectivity models. Population structure of snow leopards is mostly influenced by human presence and presence of frequented roads, which represent a substantial dispersal barrier. Habitat suitable for this species is greatly restricted by altitude, however, during dispersal they are able to overcome areas with higher elevation than what is optimal for them. Pronounced genetic difference was found between central European and Carpathian...
Dispersal mechanisms of protists
Křivská, Lucie ; Škaloud, Pavel (advisor) ; Urbánková, Pavla (referee)
Protists are ubiquitous organisms, they are main particles in foodchains, but they also cause many economical problems in areas of healthcare, agriculture and in food industry. Their biogeography is discussed in many academical debates and even that our methods are relatively advanced, there is still not only one accepted theory but two of them. However it is true that the moderate endemicity model is probably the correct one. This text sums up our existing knowledge in the field of protist distribution and their dispersal over whole planet, in terrestrial and aquatic environments. Mechanisms of dispersal are very coplicated and complex problematics. The resting stages are also important for successful dispersal, not only as a reaction to unfavourable conditions. Dispersal is affected by climatic conditions in investigated area and thus it is not easy to predict the patterns of dispersal. Human influence is getting more important on biogeography of microorganisms, including the history. This topic is becoming more popular these days as it becomes obvious it is importnat to know the patterns of dispersal. There are also adaptations and tolerances discussed. Keywords: environmental factors, dispersal, distribution, endemic species
Diversity of the genus Frustulia in northern Europe
Scharfen, Vojtěch ; Urbánková, Pavla (advisor) ; Veselá, Jana (referee)
Genus Frustulia was chosen for this work due to the continuity of the previous research of our phycological group. Using molecular techniques, it was found that a number of morphologically defined species of diatoms is cryptic species complex, which may have limited dispersal. The aim of this study was to: 1) evaluate the diversity of the genus Frustulia in northern Europe by molecular methods and classify found species in the phylogenetic context of related species; 2) find out if it possible to identify the isolated species in natural samples by using morphological characters. There have been analyzed 234 strains by molecular methods. Isolated ones were in four clades. 86 % of the strains belonged to a generic complex F. crassinervia-saxonica. Two strains were identified as species F. gaertnerae and F. septentrionalis. The last line was not described yet so it was labeled as F. sp. This line is closely related to the species F. maoriana, which is considered to be endemic in New Zealand. Phylogeny of the genus was created based on a dataset of four molecular markers. Published morphometric data were then compared with 264 cells photos taken by scanning electron microscope. There was done surveillance comparison of the results of the analysis of quantitative and qualitative characters with...
Local dispersal of Golden-ringed dragonfly Cordulegaster boltonii
Hančíková, Barbora ; Černý, Martin (advisor) ; Dolný, Aleš (referee)
We carried out a pilot study of local dispersion and patterns of movement of Golden- ringed dragonfly Cordulegaster boltonii (Odonata: Cordulegasteridae). Cordulegasteridae is a family with many primitive traits present and rather restricted geographical distribution ranges (at least among European species). Their migration seems to be limited despite the body size that predetermines them to high mobility over large spatial scale. Linear habitat (upper parts of narrow forest streams) specialisation along with behavioural ecology (peculiar premating habit of scanning streams for females) is a unique life history, which bring lot of questions. We collected mark-release-recapture data during two adult flight seasons in year 2010 and 2011. We were simultaneously capturing patrolling males along three separate streams (Dračice, Koštěnický and Struha) in total length of 9.9 km in, located in the Natural park Česká Kanada, in the Southern Czech Republic. We captured and marked 440 individuals and recorded 113 recapture events (26 % recapture rate) in year 2010 and 355 individuals were marked, 171 recapture events made (48 % recapture rate) in 2011. Our data suggested high level of stream fidelity (only 10 inter stream dispersal events, 2.8 % dispersal rate). What was as well reflected in a closeness of...
Disperzní a letová aktivita pakomárů stojatých vod (Diptera: Chironomidae)
VEBROVÁ, Lucie
I first review the significance of dispersal for individuals and populations including the role of the most significant environmental drivers on separate phases of dispersal. Emphasis is put on aquatic insects inhabiting small standing waters. The following manuscript summarizes a quantitative study of diel and seasonal flight patterns of adult Chironomidae in the Cep II sandpit in southern Bohemia. It provides one of the first comprehensive treatments of the effect of weather conditions and seasonality on the flight activity of adult Chironomidae, phenology of most common species and differences between terrestrial and aquatic species.
Migrations of dragonflies and damselflies (Odonata)
Hančíková, Barbora ; Černý, Martin (advisor) ; Waldhauser, Martin (referee)
This study is aimed at the phenomenon of migration, which is not still fully explored and which, by different circumstances, undergo several species of dragonflies (Odonata). Only for a few species from several tens of migrants generally, their migration route and strategies are explored. These case studies are described and I am also dealing with those species of dragonflies for which migration is not fully explored, and I am pointing out the other possible fields of research. One of the aims of my work is the comparison of different attributes and strategies of migration in dragonflies with other migrants from insect as well as the migratory birds.
Impact of river system structure on the genetic diversity of reed populations
Fuxová, Gabriela ; Fér, Tomáš (advisor) ; Kubátová, Barbora (referee)
Many plant species are closely related to river biotopes or to biotopes influenced by rivers. River systems create important linear corridors in ecosystems and directly or non-directly influence spatial spread of species in these environments. This offer many questions about species spread in this system. We can answer these questions by using molecular methods. Using 10 microsatellite (SSRs) primers, 202 individuals of Phragmites australis from 60 populations were analysed. Those analyses allowed reveal kinship of individuals, obtain information about spatial spread of populations and about spreading of common reed. Phragmites australis creates both - monoclonal and polyclonal - populations. Dependence of rate of clonality on environment was revealed. Populations from river banks are more monoclonal, populations from pond shores are more polyclonal. Populations are isolated. The highest percentage of variability was explained on among-population level. This is common for anemochoric species. Communication between populations is present, more on shorter distances. Evidence for vegetative spread was found on short distance. Generative spread is much more common. Long-distance spreading is mediated by generative diaspores - seeds. This spreading includes within-river spread, among-river spread and spreading...

National Repository of Grey Literature : 26 records found   previous11 - 20next  jump to record:
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