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Avian communities of overgrown wetlands near fishponds in the Třeboň basin
Tuháček, Filip ; Hořák, David (advisor) ; Voříšek, Petr (referee)
Wetlands are one of the most unique and threatened biotopes on earth. Encroachment, mainly due to the cessation of traditional management leads to the appearance and spread of shrubs (mostly willows, Salix spp.). ey eventually change the appearance of the wetlands into forest- like habitats. is diploma thesis describes avian communities of overgrown wetlands and compares them with those of non-overgrown wetlands, i.e., reedbeds and low vegetation (mainly sedges, Carex spp.). Although the overgrown wetlands did not have the lowest species and population densities, in comparison with non-overgrown wetlands, the densities of wetland specialists and endangered species, such as Savi's Warbler (Locustella luscinioides), Bluethroat (Luscinia sve- cica), and Water Rail (Rallus aquaticus) were lowest in the willow-dominated wetland compared to non-overgrown. Due to the overgrowth of the wetland, the avian communities are more wo- odland and common bird species, such as Common Chiffchaff (Phylloscopus collybita), Willow Warbler (Phylloscopus trochilus), and Great Tit (Parus major). We also wanted to investigate and compare the invertebrate biomass in overgrown and non-overgrown wetlands. We wanted to find out how avian communities depend on the food resources in wetlands around the South Bohemian fish ponds....
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Spatio-temporal activity of African ungulates at water sources in Mogalakwena River Reserve, South Africa
Homoláč, David ; Hořák, David (advisor) ; Bennitt, Emily (referee)
The large mammals of African savannah are a well-studied group of animals, but few studies focus on the temporal, circadian activity of this group of mammals. Such studies either use problematic methods of data collection (webcams, direct observations) or have been conducted in national parks or large reserves, where movement of the animals is not limited with anthropogenic structures. In such sites, the community of large mammals is usually complete, including the guild of large carnivores. Thus, small, fenced off reserves without a complete community of large mammals are understudied. Therefore, this work focuses on the spatio-temporal activity of ungulates at water sources in the Mogalakwena River Reserve in South Africa, which is an example of a reserve without large predators except the leopard (Panthera pardus). I used camera traps to assess the activity of ungulates, which I placed alongside the Mogalakwena River and at the water holes. With the help of artificial intelligence, I classified the photos to the level of activity of each species. I then tested this activity over space (type of water source) and against biotic and abiotic factors. The activity of ungulates at water sources is influenced by the maximum daily temperature, as the activity shifts to the evening hours during higher...
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Exceptions to the positive relationship between species diversity and environmental heterogeneity
Srpová, Tereza ; Hořák, David (advisor) ; Divíšek, Jan (referee)
The positive relationship between environmental heterogeneity and species richness has been taken for granted for many years. However, recent studies have revealed possible alternatives to this positive relationship, such as negative or unimodal relationship. There are many possible explanations for these alternative relationships. Increasing spatial heterogeneity of a biotope of a given size inevitably leads to reduction in the effective area available to the organisms inhabiting it. At the same time, increased environmental heterogeneity can lead to fragmentation and isolation of biotope patches, which can have negative consequences for the species richness of the community. Inadequate methodology may be one of the reasons why these alternative relationships have only been discovered in the recent years. Correct information on the relationship between environmental heterogeneity and species richness is essential for decisions on biodiversity conservation. For this reason, it is necessary to discover such alternative relationships in specific ecosystems, which we aim to protect, and to always take them into account, even if they are less common.
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Aesthetical value of environmental heterogeneity
Bufka, Ondřej ; Hořák, David (advisor) ; Janečková Molnárová, Kristina (referee)
Throughout their lives, people are in constant contact with the natural environments that surrounds them. The aesthetic value of this environment has a great infuence on man's relationship with it. There is also a connection between the aesthetic value of the environment and it's heterogeneity. Environmental heterogeneity includes physical, topographical and also biodiversity of the environment. It is also an important factor influencing it's ecological and aesthetic value. High levels of heterogeneity in a landscape can have a positive impact on biodiversity, resistance against disturbances and also on people's aesthetic preferences. Positive effects resulting from people's contact with visually attractive landscapes can further motivate them to protect and conserve nature and even improve their mental health. The aesthetic value of the environmental heterogeneity therefore has a great, but not yet fully exploited, potential for nature conservation and landscape management.
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Population trends of wetland birds in Europe
Karasová, Lucia ; Hořák, David (advisor) ; Musil, Petr (referee)
Waterbird research has grown in importance over the decades, attracting both professional and public interest due to its fascinating nature. Historical records of waterbird abundance have allowed the analysis of population trends and the identification of potential aberrations. Europe is an important region for many breeding and wintering species, providing a wide range of suitable habitats throughout the year. Several wildfowl and diver species, but also common waders, wading birds or cormorants exhibited a long-term stable or increasing population trends. The most decreasing trends were reported for some diving ducks, grebes and grassland-nesting waders. Despite reports of apparent declines in waterbird populations, the identification of ecological causes is complex due to the diverse characteristics of different waterbird species, making this a broad and complex topic to investigate. From the mentioned ecological drivers, habitat loss has the most negative impact on waders, whilst climate change could be associated with the shifting of breeding and wintering ranges. The birds breeding on wet grasslands were mostly affected by modern agriculture, and nowadays, their populations are threatened. KEYWORDS wetland birds, non-passerines, population dynamics, Europe, conservation biology
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High order numerical method in modelling and control systems
Veigend, Petr ; Horák, David (referee) ; Schirrer, Alexander (referee) ; Šátek, Václav (advisor)
Systémy pro řízení a regulaci jsou používány téměř ve všech průmyslových oblastech. Pro jejich modelování se často používají diferenciální rovnice, které popisují dynamické chování těchto systémů a umožňují je detailněji analyzovat z hlediska přesnosti, stability, výkonu a reakcí těchto systémů v reálném čase. V této oblasti se běžně nepoužívají metody vyšších řádů, protože vykonávají velké množství operací. Tato práce zkoumá numerické řešení obyčejných diferenciálních rovnic s použitím metody s proměnným řádem a proměnnou velikostí kroku, která je založena na Taylorově řadě. Metoda je navržena jak pro lineární, tak pro nelineární problémy a jsou implementovány její optimalizace pro snížení výpočetního času bez degradace jejích vlastností. Pozitivní vlastnosti metody jsou demonstrovány na sadě příkladů z technické praxe. Výsledky práce ukazují, že metoda založena na Taylorově řadě může být použita v oblasti řízení a regulace a má lepší vlastnosti než běžně používané metody.
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Apartment Building - Design of Selected Reinforced Concrete Elements
Jakoubek, Lukáš ; Horák, David (referee) ; Švaříčková, Ivana (advisor)
The bachelor thesis is focused on the continuous static solutions of monolithic reinforced concrete ceiling construction and the three-flight staircase in the five-storied apartment house. The entire structure is designed from concrete. To determine the effects of internal forces used computational design of Scia Engineer 2013.1. Assessment of the elements is performed by the first limit state. Work includes developing a static calculation, design reinforcement drawings, shapes and reinforcement drawings solved elements.
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Design of the selected parts of the concrete object
Hrvolová, Markéta ; Horák, David (referee) ; Švaříčková, Ivana (advisor)
The aim of the bachelor´s thesis is the static solution of the selected parts of the reinforced concrete object with drawing documentation included. Project describes the design and assessment of the monolitic slab structure and stairway slab by the first and second limit state. As the part of the thesis is the attachment describing the process of modeling the truss structure. For calculation of the internal forces was used software Scia Engineer.
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Planar antenna arrays for RFID applications
Pochobradský, Jakub ; Horák, David (referee) ; Lukeš, Zbyněk (advisor)
This thesis describes the basic principles of radio frequency identification, basic characteristics of patch antennas, the possibility of their feeding and design of planar antenna series. Are discussed, impedance matching options. The selected antenna arrays were realised, measuring their parameters was down and measured parameters was compared with simulation results.
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Design of the Timber-Concrete Composite Ceiling Structure
Válek, Jakub ; Horák, David (referee) ; Švaříčková, Ivana (advisor)
The reconstruction of existing houses is currently a frequent issue. This work deals with the possibilities of reinforcing wooden ceilings with the focus on ceiling reinforcement using an over concrete slab. This suggested ceiling reconstruction work is desirable from the point of view of the rigidity of the object in the horizontal direction. The work includes the proposition for the composite, according to various norms and their comparison regarding the economic side of the design. The work further provides a description of the experiment, its preliminary results and its comparison with the theoretical calculation.
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