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Surface ozone influence on native vegetation: results based on ozone visible symptoms and stomatal flux
Matoušková, Leona ; Hůnová, Iva (advisor) ; Albrechtová, Jana (referee) ; Hovorka, Jan (referee)
Regarding the vegetation, the most affected areas by high levels of surface ozone (O3) are the mountain ridges. Our study has been carried out in the Jizerske hory Mts. High O3 levels together with the convenient environmental conditions for stomatal conductance could be a threat for the health of recovering ecosystems in this area. The aims of this study was both to assess the influence of O3 on vegetation in the Czech mountains and to provide recommendations and outlooks for possible future using of relatively new methods (visible symptoms and stomatal O3 flux modelling) used for O3 impact assessment on native vegetation in the field; that means physiologically relevant methods for the determination of O3 influence. During 2006 and 2007, O3-like visible symptoms were assessed on the leaves of seven species at four sites. Symptoms on only two species (Fagus sylvatica L. and Rubus idaeus L.) have been determined as O3-induced. To our knowledge, it is the first study in the Czech Republic in which the O3-like symptoms on native plants have been verified by the Ozone Validation Centre for Central Europe. Our results based on O3-induced symptoms indicate that ambient O3 is likely to have a much lower impact than expected, considering the measured O3 concentrations (measured with passive samplers) and...
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Contaminant binding to colloids in water from a mining/smelting area
Walter, Dominik ; Ettler, Vojtěch (advisor) ; Faimon, Jiří (referee)
This study deals with the association of trace elements with colloids and particles in surface waters and groundwaters of mining and smelting district of Příbram. Colloids were studied using combination of cascade filtration a tangential flow ultrafiltration method to separate individual colloid fractions. Colloids were separated by filtration membranes with nominal pore size 0,8 μm, 0,45 μm, 0,1 μm, 100 kDa, and 5 kDa. Water samples were analyzed using ICP-OES, ICP-MS and HPLC. The data were used for thermodynamic modeling using PHREEQC-2 programme. The results show that major and trace elements can be divided into several groups, based on their abundance in individual size fractions. Most elements dominate in fraction of truly dissolved matter as dissociated ions (< 5 kDa), maximum concentration in colloid fraction is 5-20 % and almost exclusively in fraction 5 kDa - 100 kDa. Gradual decrease of concentration in all fractions at low ionic strength (1,2 mmol/l) was observed in case of elements such as As, Co, Cr, Si, Sb and U. Gradual decrease of concentration in several samples was observed for Cd, Fe, Pb, Mn and Zn. Dominant binding to colloids and particles in surface waters was observed for Fe and Pb, where these fractions accounted for over 90 %. The main factor influencing colloid...
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Behaviour and ecology of leopard geckos (Eublepharis macularius)
Jančúchová Lásková, Jitka ; Landová, Eva (advisor) ; Moravec, Jiří (referee) ; Sedláček, František (referee)
During evolution, the natural selection favours individuals with the best survival strategy and the highest reproductive success. From the evolutionary point of view, hybridization plays an important role in the process of speciation. Avoiding predators by choosing the most appropriate antipredator strategy increases the animal's chances of survival as well. Studying fitness consequences of hybridization and predation in Eublepharis macularius (Eublepharidae) was the main objective of this theses. Compared to other vertebrate groups, the reliable records on hybridization and its effect on the hybrid's fitness (fertility, survival) in lizards are scarce, despite their ability to hybridize between genetically distant species. These effects were examined in two species of eyelid geckos (E. macularius and E. angramainyu). We aimed to discover whether they were willing to hybridize with a heterospecific species and how the fitness of the hybrids would be affected. Similarly, were studied more genetically related forms of E. macularius species complex, the potential precopulatory barriers, and fitness cost of this hybridization. Analysis of published data has shown that the lizards hybridize between very phylogenetically distant species and are even "more successful" than birds or turtles. Surprisingly,...
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Modifications of inner walls of electrophoretic capillaries using positively charged anchors
Stávek, Petr ; Křížek, Tomáš (advisor) ; Coufal, Pavel (referee)
Electroosmotic flow plays a crucial role in capillary electrophoresis, as it can impact both the resolution and duration of the separation process. Altering the electroosmotic flow can be achieved through dynamic coating of the inner capillary surface. The primary objective of this work was to investigate the potential of various positively charged anchors in providing a suitable dynamic coating for capillary electrophoresis. At first, experiments were carried out with neopentyl anchors PK 1291, PK 941, PK 1300 and PK 1294 using four different coating methods. Obtained coatings demonstrated the ability to suppress the electroosmotic flow, although the stability of the obtained coatings varied significantly among the individual anchors. PK 941 demonstrated the most promising results within this group. Subsequently, measurements were also performed using the cyclodextrin anchor PK 1281, which yielded the most favorable outcomes. It was observed that depending on the background electrolyte and the chosen coating method, this anchor could either reverse the direction of the electroosmotic flow or nearly completely eliminate it. Key words: capillary electrophoresis, electroosmotic flow, dynamic capilary coating, positively charged anchors.
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Circadian regulation of the glymphatic system and its connection with the development of neurodegenerative diseases
Kuznetsov, Egor ; Sumová, Alena (advisor) ; Kubištová, Aneta (referee)
Due to the absence of an active lymphatic system of the brain and the responsible nodal system, it has long been unclear how interstitial metabolic waste products, in particular amyloid-β, tau- protein, α-synuclein and other biomarkers associated with the development of neurodegenerative diseases, are eliminated. A key role in this process is played by the glymphatic system, a complex network of tunnel-shaped perivascular spaces (PVSs) that conduct the flow of cerebrospinal fluid. These spaces are surrounded by astrocytes, responsible for the transport of fluids and the removal of metabolites. Studies suggest that the glymphatic system is subject to an endogenous circadian clock, and there is an established correlation between the volume of perivascular spaces and, with it, the rate of cerebrospinal fluid flow and sleep. Factors affecting the function of the glymphatic system include pulsation of blood vessels, spatial orientation of the body and functionality of aquaporin-4 (AQP4). Dysfunction of the glymphatic system plays a key role in the aging of the brain and the development of various neurodegenerative diseases. The aim of the work is to summarize the known knowledge about the regulation of the glymphatic system and its influence on the development and prevention of neurodegenerative...
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Global phylogeography of the deep-sea fishes
Knězů, Tereza ; Musilová, Zuzana (advisor) ; Vukićová, Jasna (referee)
Phylogeography of deep-sea fish remains poorly explored, largely due to the extreme conditions in which these organisms live and limited technological capabilities for researching these species. The aim of this thesis is to summarize the information known about the phylogeography of deep-sea fish, identify factors influencing population distributions, and connect them on a global scale. The distribution of deep-sea fish populations is influenced by physical, topographic, and hydrographic factors. Their connectivity is driven by the migratory abilities of fish and the utilization of marine currents for their dispersion. Migration is divided into vertical and horizontal. The vast majority of deep sea fish undergo some form of migration, at least during ontogenetic development. The most common is diurnal vertical migration, where fish regularly move to shallower depths at night for feeding. Molecular methods, mainly mitochondrial DNA markers, were used for research to determine the phylogenetic tree of species. The results suggest that the topography of the seafloor is rarely a barrier to the flow of genetic information. Furthermore, the results often refute the hypothesis of isolation caused by the distance between populations. They often exhibit a relatively high rate of panmixia. When speciation...
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Film tourism - Vltava as an object of interest for film productions and subsequently tourists
Veterník, Jan ; Fialová, Dana (advisor) ; Kubištová, Tereza (referee)
Film tourism: Vltava as an object of interest for film productions and subsequently tourists Abstract The bachelor's thesis focuses on the phenomenon of film tourism, a still developing form of tourism in the Czech Republic. The first part of the thesis is devoted to the theory of film tourism demonstrated on international examples. This theoretical part also includes a chapter on destination marketing and promotion of film locations. In the second part of the thesis, the theoretical principles from the first part are applied first to the Czech Republic, and then specifically to the Vltava River. On the Vltava, with the help of the filmovamista.cz website, significant films and TV series are presented and, in connection with this, locations with the potential for the birth of film tourism are revealed. Key words: Czechia, films, film places, film induced tourism, Vltava
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The effectivity of ecoducts for wildlife crossing of landscape fragmented by a highway network
Leštinová, Eliška ; Sedláček, Ondřej (advisor) ; Uhlíková, Jitka (referee)
Ecoducts or wildlife overpasses are migration objects that are often built not only in the Czech Republic, but in Europe as well. They enable animals to safely cross an obstacle, for example a road or a railway. Furthermore, ecoducts enlarge the home ranges of species, ensure gene flow between populations, and influence interspecies interactions. Ecoducts built in the Czech Republic are often criticized, especially because of their high cost and low efficiency. Majority of the existing studies compare ecoducts with other types of migration objects, such as underpasses, and often focus on selected aspects of these structures, such as their dimensions or location. There are very few summarizing studies focusing solely on ecoducts and what influences their permeability for animals. In this paper, I summarize what species are using ecoducts in Europe and North America, and I discuss how is the use of an ecoduct by animals affected by anthropogenic disturbances, design of the ecoduct, and its location in the landscape. Lastly, I describe monitoring methods used when studying wildlife overpasses. In the end, I summarize gained knowledge and list gaps in the existing research.
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Hydraulic verification of water flow
Adámek, Milan ; Julínek, Tomáš (referee) ; Duchan, David (advisor)
This bachelor thesis deals with a comprehensive hydraulic assessment of the Svitava River with an emphasis on nature-based flood control measures and watercourse revitalization. In the theoretical part, an overview of current approaches to watercourse revitalization and flood protection is given. The practical part focuses on a detailed analysis of water flow in a specific section of the Svitava River, which is performed using a computational tool such as HEC-RAS. On the basis of the obtained results, various options for stream revitalisation and flood protection are proposed and subsequently subjected to hydraulic assessment.
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