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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Studium potravy velkých savců: metodologický přístup / Towards a better understanding of ungulate diets: a methodological approach

Holá, Michaela January 2016 (has links)
Populations of European ungulates have grown substantially over recent decades, resulting in considerable environmental and socio-economic impacts. Availability and quality of natural and supplemental food sources are among the main factors driving their population dynamics. Detailed knowledge of feeding strategies of management-targeted species is therefore of primary importance for their successful management. Over time, methods to study the feeding strategies of animals have also evolved considerably but each has its advantages as well as limitations. This doctoral thesis uses a combination of traditional methods (i.e. stomach content analysis) and novel methods (i.e. stable isotope analysis, near infrared reflectance spectroscopy) to achieve a better understanding of feeding strategies of two important ungulate species (i.e. wild boar and red deer) in the Czech Republic, where their populations are on the rise and supplementary feeding is rampant. Next, this dissertation aims to introduce and to establish a basis for these novel methodological approaches for the study of free-ranging individuals. In this respect, it also addresses methodological issues related to their application in this field. The diet composition of wild boar was investigated by examining stomach contents in order to identify their dependence on food resources of human origin (i.e. agricultural crops and supplemental foods). Foods of human origin were the dominant diet type and constituted the bulk of the diet of wild boar throughout the year. A necessary prerequisite for application of stable isotope analysis is the trophic discrimination factor (i.e. systematic difference between the isotopic composition of the consumer tissues and that of the diet), which was experimentally determined for stable carbon and nitrogen isotopes, the two most commonly used in ecology, in hair tissue of wild boar and red deer. Furthermore, possible sources of variation (such as sex, age, body weight, and lactation) on isotopic discrimination were investigated. The results of the experiments provide a starting point for the successful use of stable isotope analysis in field studies on wild boar and red deer. Finally, application of near infrared reflectance spectroscopy was proven to be useful in measuring faecal indices of food quality for red deer. The results of this thesis will contribute towards efficient management of wild boar and red deer in the Czech Republic.
2

Archeozoologie neolitu Čech / Archaeozoology of the Neolithic of Bohemia

KOVAČIKOVÁ, Lenka January 2011 (has links)
An archaeozoological analysis of the assemblages of animal bones and teeth of Neolithic (Linear and Stroked Pottery cultures; approx. 5500-4200 BC)settlements in Bohemia, provide new elements on the way of life of early farmers. By means of study of animal bones and teeth we can specify the role of domestic and hunting animals in the Neolithic economy, define the herd management strategies for main domestic animals and focus on the environmental reconstruction and investigation of births distribution of domestic animals (for exemple of cattle in the case of this study) through the analysis of the carbon and oxygen isotopic compositions of fossil tooth enamel bioapatite. To achieve these objectives, we can use, except standard archaeozoological methods and stable isotope analysis, more specific procedures, e.g. determination of damaged bones of animals using the ELISA test.
3

Mobilita lidských populací na konci doby kamenné / Mobility of human populations at the end of the Stone Age

ČERVINKA, Pavel January 2017 (has links)
The presented work entitled "Mobility of Human Populations at the End of the Stone Age" describes, generalizes, summarizes and subsequently evaluates the factors of migratory tendencies in prehistory - for the period of Neolithic over Eneolithic to Early Bronze Age. Emphasis is placed on the clarification of all interdisciplinary issues. Further on a detailed description of individual processes and archaeological approaches to them. As a basis for my own research, a database of data impacted by articles based on the study of strontium isotopes was created. In the next steps, the database was processed using statistical tools and its outputs were contingency tabletables and charts. Spatial assessment and their contexts were conducted in the GIS (Geographic Information System).
4

Přenosové efekty v rámci ročního cyklu rákosníků velkých: celoareálová studie se zaměřením na rozdíly mezi pohlavími a populacemi / A range-wide assessment of carry-over effects within the full annual cycle of the Great Reed Warbler with a focus on sex and population differences

Brlík, Vojtěch January 2019 (has links)
Movements of long-distance migratory birds are frequently well timed and routed in order to maximise individual fitness. However, individual timing of events or environmental conditions experienced have a potential to carry over into subsequent annual cycle stages and may have delayed fitness consequences. Therefore, knowledge of these seasonal interactions is crucial to identify key periods and regions that limit survival beyond the breeding period and thus to fully understand population dynamics of migratory species. Despite current evidence for seasonal interactions, there is no detailed knowledge of the complex of relationships within the full annual cycle, differences between sexes and populations or impact of environmental conditions during moult in one species. To unveil this system of seasonal interactions within the annual cycle, we directly tracked 103 great reed warblers (Acrocephalus arundinaceus) using light-level geolocators from five breeding sites across the breeding range to obtain information on timing and positions of annual cycle events. We then combined this information with various remotely sensed habitat condition metrics and stable isotopic composition of feathers from the non-breeding grounds to identify and quantify carry-over effects within the full annual cycle. Our...
5

Studium autekologie vybraných taxonů křídových rostlin pomocí izotopů uhlíku / Autecological study of selected Cretaceous plants using stable Carbon isotopes

Zahajská, Petra January 2016 (has links)
1 Abstract This thesis presents an analysis of fossil plants from the Cenomanian Peruc-Korycany Formation of the Bohemian Cretaceous Basin and from the Bückeberg Formation of the Lower Saxony Basin in Germany. Based on earlier studies, both areas provide sediments that are considered to have developed in tidally influenced fluvial systems. Studied fossil plants are represented by ginkgoalean plant leaves (Ertemophyllum, Tritaenia), branches of conifers (Frenelopsis) and lauroid angiosperms (Eucalyptolaurus). Frenelopsis, Eretmophyllum and Tritaenia are considered to be halophytic plants, while Lauroid angiosperms were considered to grow in fresh water conditions. The fossil plants were studied using cuticle analysis and two methods of stable carbon isotope analysis: Bulk carbon isotope analysis and Compound Specific Isotope analysis. For cuticle analysis samples were observed and documented macroscopically and microscopically. To specify the environmental conditions, recent samples from three salt marshes in Great Britain were studied and analysed using the same methods as the fossil samples. The data from all observations and measurements were processed and their interpretation supported the modelled environment based on the sedimentological data. Frenelopsis were growing in a haline environment with low...

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