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The use of stable isotopes in the trophic ecology of birds
Rusnáková, Michaela ; Hořák, David (advisor) ; Procházka, Petr (referee)
Recently, the use of stable isotope analysis has been becoming increasingly common in ecological studies of animals. This interesting method is based on the premise that the isotope composition of consumer's tissues is related to the isotope composition of the sustenance consumed. This allows us to explore the contribution of individual food sources to the diet of species, populations or individuals, and at the same time to study their position in the trophic chains. The method enables us to research even omnivores, consuming variable food with different nutrients and isotope composition. Nevertheless, isotope values can differ depending on diet preferences, species physiology and the tissue type used for the analysis. This review summarizes current knowledge and results in the topic of stable isotope analysis, particularly in ornithological studies where the approach in question has been used to study the diet and trophic position. Powered by TCPDF (www.tcpdf.org)
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Study of water flow and geochemical processes in the unsaturated zone of carbonate and salt karst
Kamas, Jiří ; Bruthans, Jiří (advisor) ; Tesař, Miroslav (referee) ; Buzek, František (referee)
Water flow and geochemical processes within the unsaturated zone (UZ) in two distinct types of karst environment were investigated using natural tracers (chemistry, stable isotopes 13 C, 18 O, 2 H, and 3 H, 14 C, 87 Sr/86 Sr). The extent of horizontal flow component and the response of drip water chemistry to recharge events were examined in the Moravian Karst (Czech Republic), while the character of water flow and its chemistry were studied in salt diapirs in southeastern part of the Zagros mountains (Iran). Under the conditions of well-developed epikarst, the horizontal flow component, defined as Hmax/T (Hmax = horizontal migration component, T - thickness of VZ) typically reaches values of 0.1 - 0.6 (Moravian and Slovenian Karst). However, in areas where epikarst was stripped off by glacial or human activity, the proportion of horizontal flow component is far greater (Hmax/T 1.6 - 24). This parameter is vital for the design of water source protection zones above caves. Nitrate mean residence time in 120 m thick VZ of the Moravian karst exceeded 16 years. The VZ above the Ochoz Cave (Moravian Karst) represents a semi-open to open system with respect to soil CO2. Under a high drip rate (high flow), the event water only made 5% of the total. During the year, water degassing and so called prior...
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Multiproxy evidence of Late Pleistocene environmental changes in the loess/paleosol sequence of Bůhzdař
Flašarová, Kristýna ; Strouhalová, Barbora (advisor) ; Trubač, Jakub (referee)
Loess-paleosol sequences preserve information that can be used to reconstruct paleoenvironement, specifically the climatic conditions and the vegetation present at the time of their formation. A dense network of reliably analyzed sequences from different geographic locations is crucial for representation of ecological and climatic trends during the Pleistocene (Frechen, 2011). The aim of this thesis is to fill the gap in the geographical distribution of well described loess-paleosol sequences in Central Europe. Therefore, it focuses on a loess- paleosol sequence in Bůhzdař, situated 9 km NW of Prague, Czech Republic. This profile was last studied in 1952 by naturalist Vojen Ložek. This thesis uses a number of analyses in order to get a multi-proxy record of local paleoenvironmental changes archived in a sequence of alternating loess sediments and paleosols in Bůhzdař. Geochemical approaches are combined with grain size distribution to define climatic conditions at the time of formation of the strata. Key words: loess/paleosol sequences, Bůhzdař, Czech Republic, particle size distribution, total organic carbon, XRF, XRD, stable isotopes 13 C and 18 O
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Carbon and Oxygen Stable Isotope Ratio from Foraminiferal Tests as a Key to the Paleoenvironmental Interpretations in the Middle Miocene of the Carpathian Foredeep (Central Paratethys)
Scheiner, Filip ; Holcová, Katarína (advisor) ; Soták, Ján (referee)
The (Lomnice) LOM-1 borehole records a nutrient-rich quiet environment of the outer shelf to upper bathyal in the Mid Badenian (sensu Hohenegger et al. (2014)) of the Carpathian Foredeep. The LOM-1 borehole is rich of a fossil content with a relatively good preservation. The studied section can be correlated with the interval from 14.6 Ma (the FO of Orbulina spp.) to 13.42 Ma (the LO of Sphenolithus heteromorphus) which agrees with the beginning of the "Middle Miocene Climate Transition". The foraminifera for the carbon and oxygen stable isotope analysis were picked from the fraction 0.063-2 mm. The suitability for the stable isotope analysis was carefully evaluated based on the inner wall preservation. The isotopic analysis was done for fifteen samples with total 373 tests analyzed. Each analysis was performed from exactly one test. The following foraminiferal genera from different paleobiotops were used for the isotope analysis: Globigerina bulloides; Orbulina universa, Praeorbulina glomerosa; Globigerinoides spp.; Uvigerina spp.; Heterolepa dutemplei; Cibicidoides spp.; Gyroidinoides spp. and Melonis pompilioides to document the isotopic signal for the superficial and bottom waters. The oxygen and carbon isotope analysis from foraminiferal tests were used for the verification of the...
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Altitudinal migrations in animals and their study methods
Zenklová, Tereza ; Sedláček, Ondřej (advisor) ; Klvaňa, Petr (referee)
Migration as a response to the seasonality of the environment is common in many animal taxa. Strong fluctuation of the climate is usually connected to regions in the temperate zone, quite common is in the tropical regions as well. Typically, it is even more pronounced in high altitudes. In such environment, many animals could migrate altitudinaly as a response to changes in the climatic conditions or food abundance. But determinants of altitudinal and long-distance latitudinal migrations could be different. The objective of this work is to determine factors influencing altitudinal migrations in diverse taxa (particularly in birds and bats) and in different biogeographical regions. I am trying to find some common features of migrating species, such as diet or temperature and rain tolerance. Especially tropical species are partial migrants, which means that only some individuals of the population migrate. I will discuss common features of such migrating infividuals. Study methods of altitudinal migration will be a part of this research as well. The work will be primarily concentrated on tropical regions.
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Stable isotopes in study of diet in Ursidae, including fossil taxa.
Marková, Aneta ; Horáček, Ivan (advisor) ; Čermák, Stanislav (referee)
Composition of food of members of the family Ursidae is often discussed topic. Up to now, however, there is some uncertainty about the trophic level of some fossil groups. Very useful method which helps us to determine the trophic level of the fossil species and determine the relative proportion of plant and animal components in the recent ones is the analysis of the stable isotopes. This study summarizes present state of methodological approaches and possibilities of use of the stable isotopes 13 C and 15 N in the study of foraging ecology of bears. The results of the analysis of stable isotopes are presented together with results obtained by other methods. Attention is paid to groups for which the relevant isotopic data are available, with special emphasis on the cave bear, which trophic level is evaluated on the basis of stable isotopes analysis as well as in the evolutionary and nutrition context.
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Bioarcheologie středověké populace střední Evropy: vztah zdravotního stavu, sociální diferenciace a výživy.
Kaupová, Sylva ; Velemínský, Petr (advisor) ; Smrčka, Václav (referee) ; Polet, Caroline (referee)
We studied the dietary behavior and health status of a population that lived in the context of rapid change, including the development of the economic and political structures of states, the adoption of Christianity as well as the subsequent disruption of social structure and the recovery of society. Carbon (δ13 C) and nitrogen (δ15 N) isotopic values were measured in a sample of 189 adult individuals of both sexes and 74 animals representing different socio-economic contexts (power centers versus the hinterlands) and chronology: the Great Moravian (9th -10th century AD) versus late Hillfort (11th century AD) period. A sample of 41 sub-adults aged 0-6 years, representative of both Great Moravian power centers (Mikulčice) and its rural hinterlands (Josefov), was selected for isotopic analyses of breastfeeding and weaning behavior. Data on growth and frequency of nonspecific stress indicators (cribra orbitalia, porotic hyperostosis, and endocranial lesions) were analyzed in a sub-adult group. In adults, we focused on dental health (caries, periapical lesions, dental wear, and periodontal disease), the presence of cribra orbitalia and estimated adult stature. Isotopic data of the adult sample showed that the Great Moravian population had a terrestrial diet with a substantial proportion of C4 plants....
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Seasonal variability in isotopic signature of leaf water and related water compartments. An ecophysiological perspective.
PLAVCOVÁ, Lenka
Stable isotope composition of bulk leaf water is a useful proxy for geochemical and biological processes and is, thus, appreciated in ecological research and global modelling. The mechanisms determining the abundance of different isotopes in leaf water are not fully understood. The research presented in this thesis aimed to describe variability in leaf water isotopes which occurs under natural conditions and to distinguish which factors generate such variability. For that purpose, field sampling, water extraction, stable isotope analysis and measurements of several additional environmental and physiological characteristics were carried out at one sampling site during three subsequent growing seasons. The results obtained point out that oxygen isotopes rather then hydrogen isotopes have greater potential to be used in higher scale applications. Apart from that, several interesting ecophysiological interpretations of isotopic data have been made.
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