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Mineralogical forms, distribution and importance of freshwater ice
Vrbický, Tomáš ; Mikuláš, Radek (advisor) ; Pokorný, Richard (referee)
Ice is one of the fundamental components of the environment. It covers the land surface and significantly affects our lives both on a local and global level. It is the subject of considerable scientific interest, particularly in terms of its role in climate change - the ice is capable to release pollutants into the water environment or modify the composition of the atmosphere, represents a drinking water supply or "archive" of the natural environment. This thesis "Mineralogical forms, distribution and importance of freshwater ice" describes the most common forms of freshwater ice, its distribution and importance on the Earth surface and beyond. It introduces us to the issue of current direction of ice researching and approaches some open questions. Part of this work presents types of ice occurring in the Czech Republic.
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Plant - insect interactions in lower Miocene of Central Europe: palaeoclimatological and palaeoecological implications
Knor, Stanislav ; Prokop, Jakub (advisor) ; Kvaček, Jiří (referee) ; Mikuláš, Radek (referee)
The paleoecology of plant - arthropod herbivory associations constitute very important source of knowledge about the phylogeny and co-evolution of both groups. The traces of herbivory interactions between plants and arthropods on the fossil leaves are preserved as so called damaged types (DTs) clustered into distinct functional feeding groups (FFGs). The diversity and frequency of these damage traces also seem to have been strongly influenced by environmental and climatic conditions. This research has been focused on rich fossil plant assemblages from the area of the Most Basin in the north-western Bohemia. The undergoing work has comprised the diagnosis of the individual damages on the basis of their specific morphological traits as their number, size, shape and distributional pattern on the leaf surface. The next issue has involved the statistical analyses concerning the differences in the frequency and diversity of the types of damage and functional feeding groups between two separate fossiliferous layers, namely those of the stratigraphically older Bílina Delta and younger Břešťany Clay. Significant differences were confirmed in this regard, especially in connection with achieved frequency and proportional occurrences of distinct functional feeding groups in the Bílina Delta. The galls were the...
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Comprehensive study of the sandstone rock forms deterioration (Case study: Pravčická brána Arch, Bohemian Switzerland National Park)
Vařilová, Zuzana ; Přikryl, Richard (advisor) ; Vilímek, Vít (referee) ; Mikuláš, Radek (referee)
This PhD thesis contains the results of comprehensive research into the Pravčická brána Arch and surrounding sandstone massifs with focus on gaining more knowledge about natural dynamics and evolution of this rock formation, its current level of stability and the weathering processes it displays. Non-destructive methods were used for this comprehensive study; these ranged from detailed field documentation to monitoring temperature regime of the rock and included application of a geophysical survey and control monitoring of the course of arch body deformation. Laboratory testing was carried out for strength parameters and salt efflorescences together with weathered sandstones were analysed for chemical compounds. Main operating factors were monitored simultaneously, which particularly involved changes in external temperature, degree of sunlight and chemical composition of rainfall. Conventional as well as entirely new assessment procedures were used in synthesis and interpretation of the data collected, including knowledge of nonlinear dynamics of complex systems. The survey was designed to fully respect the protective conditions of the site, to make follow-up activities possible in future and to monitor any possible negative changes in the rock massif. The main results incorporate description of...
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Ichnofossils from the Lower Palaeozoic of the Železné hory Mts.
Doucek, Jan ; Mikuláš, Radek (advisor) ; Marek, Jaroslav (referee)
On five key sites of the Lower Palaeozoic of the Železné hory Mountains (Bačalský rybník, Bačalský mlýn, Palác, Rabštejn and Deblov) the detailed research involving the compilation of schematic lithostratigraphic profiles (exluding site Deblov) was conducted. Individuals of ichnotaxa Zoophycos that have maximum Middle Cambrian age were described on the site Palác. This is the third oldest finding in the world. Ichnotaxa Zoophycos was further described on the site Bačalský rybník, where they are exposed quartz siltstones, the equivalent of the Dobrotiv of the Barrandian area. Ichnofossils abundant in the study area are Skolithos, Pragichnus, to a lesser extend Phycodes and Monocraterion. Skolithos on the site Rabštejn occurs in extreme size (until 90 cm). On the site Deblov community of Skolitos ichnofacies on the area measuring hundreds of square meters were described. There was also performed ichnological imaging which showed proportional representation of each ichnotaxa. Study samples for microprobe showed differences in structure and chemistry of ichnofabrics up filling and surrounding environment.
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Price Comparison of an Apartment Building in the Cadastral Area of Přerov According to the Valid Valuation Regulations
Mikuláš, Radek ; Superatová, Alena (referee) ; Vingrálek, Tomáš (advisor)
The aim of this thesis is to determine and compare the price of the apartment building as a whole provided a combination of cost and the valuation of yield and price of the apartment building, found the sum of individual apartments in the same house after the owner of the distribution statement. In both cases it is the valuation according to valuation regulations. But because today is often valued property for purposes of credit control, I will always be the direct comparison of the valuation according to the rules of valuation estimate just for the purposes of credit control. Furthermore, they address the issue of interpreting the concept of a block of flats (lot of flats together in one house), which is frequently used, but is nowhere defined. I found that the total price of flats according to the valuation rules, is higher by 32% compared house as a whole and the award for credit management, the total price of apartments increased by 31.4%. As can be seen from the preceding sentences, the price of the apartment building can be changed only by changing the way property, no construction-technical changes, as well as 32%.
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Cave formation initiated by dissolution of carbonate cement in qartzose sandstones
Adamovič, Jiří ; Mikuláš, Radek ; Navrátil, Tomáš ; Mertlík, J.
Besides cavities of irregular shape, European sandstones also feature symmetrical cavities of spherical, ellipsoidal or teardrop shapes. Most of them are tens of centimetres across but some reach as much as 2–3 m in diameter and may coalesce into large caves tens of metres in length. Their origin has not been clearly explained yet. Based on the field comparison between such cavities in quartzose sandstones and incompletely developed cavities in carbonate-cemented sandstones, it can be demonstrated that the symmetrical cavities form by carbonate dissolution within the limits of former carbonate concretions. The diagnostic features of post-concretionary cavities include their circular or elliptical cross-section, a uniform orientation of their long axes across the region, and the presence of a set of parallel vertical joints or grooves/ribs on their inner walls. In some sandstone areas (e.g., Petite Suisse area in Luxembourg, Kokořín area in the Czech Republic), a wide variety of transitional forms can be found between the cavities and concretions forming positive relief on a vertical cliff face, depending on the position of the carbonate dissolution front in the present landscape.
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