National Repository of Grey Literature 18 records found  1 - 10next  jump to record: Search took 0.01 seconds. 
Impact of being evergreen or deciduous on the wood anatomy of the trees in polar regions during the warm geological period : case study from Upper Cretaceous of the James Ross Island (Antarctic Peninsula)
Chernomorets, Oleksandra ; Sakala, Jakub (advisor) ; Gryc, Vladimír (referee)
Global warming and its influence on the environment has become a popular and widespread issue. Nowadays, an analogy of a high latitude ecosystem during the greenhouse type of climate does not exist. The Cretaceous polar ecosystem gave us a unique possibility of understanding these extreme ecosystems and the specific adaptations of organisms to these conditions. Such types of ecosystem are crucial for a better understanding of possible future climate changes. This thesis focusses on the adaptation strategies of land plants during the Late Cretaceous in the Arctic peninsula. The land plants responded to these specific solar conditionals in two different ways: evergreen or deciduous. The fossil material for this study comes from Brandy Bay and Crame Col, James Ross Island, Antarctic. The material was collected in a continuous sequence from Kotic point to Santa Marta Formation (Cenomanian - Companian). A detailed and systematic analysis was performed on five out of fifty-five samples that well represented the studied region and age: Agathoxylon kellerense, Agathoxylon antarcticus, Araucarioxylon chapmanae, Podocarpoxylon multiparenchymatosum and Phoroxylon sp. Based on the detailed study of Agathoxylon kellerense (sample number AN34) wood anatomy and growth rings structure, adaptation strategies were...
Puerto Argentino, inhabited by the pirates and drunkards of the royalty
Mlynarčík, Štefan ; Mrva, Jozef (referee) ; Rathouský, Luděk (advisor)
Objectivity and neutrality of current makers of online maps is hampered by the fact that the most important of them who form the public opinion are largely commercial giants. Sensitivity of approaches is desirable especially in specific situations involving territorial disputes. The textual part of the thesis brings theoretical insights to the problematics of map makers policies and their preservation or violation. At the same time is describes critical cartography as a current opposition against governmental and cooperative mapping, of which counter-mapping processes are regularly used in art, too. Practical outcome attempts to reflect specific approaches of map makers depending on particular territorial disputes. It takes place mostly in online environment, using the functions of Google Street View or Google Earth and forms of counter-mapping on the OSM platform. The goal is to bring alternative realities complicating map makers policies and governing apparatus to map projects with the international coverage.
The legal regime of Antarctica and the protection of its environment
Ledl, Jakub ; Ondřej, Jan (advisor) ; Balaš, Vladimír (referee)
The purpose of the diploma thesis is to describe and summarize the legal regime of Antarctica including its evolution, functioning and the protection of its environment. Chapter one of the thesis consists of the introduction with the Antarctic continent including the natural conditions, the history of the discovering, the competition between Roald Amundsen and Robert Falcon Scott to reach the South Pole and the territorial claims of seven states in the first half of the twentieth century. The second chapter deals with the fundamental document of the legal regime of Antarctica - The Antarctic Treaty. The Antarctic Treaty was signed in Washington on 1 December 1959 by the twelve countries whose scientists had been active in and around Antarctica during the International Geophysical Year of 1957-58. The very important provisions of the Treaty contain international cooperation and prohibition of any measures of a military nature, such as the establishment of military bases and fortifications, carrying out of the military maneuvers, as well as testing of any type of weapons. Antarctica became international space which can not be appropriated by individual states. The third chapter deals with the Antarctic Treaty System and its analysis and summary. The Antarctic Treaty System regulates the international...
Ecology and diversity of microbial phototrophs in biological soil crusts of Polar Regions
PUSHKAREVA, Ekaterina Sergeevna
Biological soil crusts (BSCs) are important components of semi-arid and arid environments and occupy a large area in Polar Regions. However, their ecological functions and the diversity of major organisms are still ambiguous. Given that rapid climate change is of particular significance and the current warming is already attributed to small variations on the Earth, it is important to obtain a more comprehensive picture about the environment to predict its changes. Moreover, climate change is faster and more severe in Polar Regions than in other parts of the world. In this context, the thesis is focused on the community structure of microbial phototrophs and their ecological functions in BSCs of the Arctic (Central Svalbard) and Antarctica (Dronning Maud Land). Combining molecular and morphological techniques we described cyanobacterial community composition in BSCs and its changes along the gradient of soil crust development. Moreover, we showed how the different stages of soil crust development (from poorly-developed to well-developed) influence photosynthetic and nitrogenase activities associated with the phototrophic community.
Historical record of the fairyshrimp Branchinecta gaini in the James Ross archipelago, and its phylogeography
Pokorný, Matěj ; Sacherová, Veronika (advisor) ; Janko, Karel (referee)
The Fairy shrimp Branchinecta gaini Daday, 1910 is the largest freshwater invertebrate in Antarctica and the top-level consumer of local freshwater food webs. Ecological demands of B. gaini that are accompanied by 'ruderal' life strategy together with its spatial distribution that exceeds to Patagonia indicate that it had survived last glacial period in South America and expanded to Antarctica shortly after this epoch endeed. On James Ross Island that is the most extreme environment where B. gaini occurs today was this fairy shrimp considered extinct until year 2008. Its disappearance was based on paleolimnological analysis of several lake sediment cores according to which it inhabited this island between years 4200 to approximately 1500 before present when it died out because of changes in lake catchments caused by harsh neoglacial conditions. Paleolimnological analysis of Monolith Lake presented in this study has shown that this assumption was wrong and B. gaini has lived on James Ross Island throughout neoglacial period up to recent time. Phylogeographic analysis of 16S rDNA of specimens from Patagonia, South Orkneys, South Shetlands and James Ross Island revealed that its high morphological diversity is not supported by this gene and that all examined populations of B. gaini is one species with very few...
Crustaceans of Antarctic lakes - past and present status
Pokorný, Matěj ; Sacherová, Veronika (advisor) ; Nedbalová, Linda (referee)
Antarctic continent is one of the most severe regions on Earth and it is characterized by low annual temperatures, low precipitation, extensive ice cover and low energy input from the Sun. Nevertheless its lakes host not only microbial communities and protists but in many cases even in the most extreme localities also metazoans, especially rotifers and crustaceans. For at least the last 15 million years Antarctica has experienced massive glaciations that shape the distribution of organisms on this continent. Although it was originally thought that freshwater animals did not survive Quaternary glaciations in situ but migrated to milder regions in the north, nowadays it appears that at least in some cases it is not true. Direct evidence of survival of rotifers (Notholca sp.) and crustaceans (Daphniopsis studeri) in Antarctica was given by paleolimnological studies that were carried out in the Larsemann Hills and circumstantial evidence for permanent survival of crustaceans in Antarctica (e.g. Gladioferens antarcticus) is also growing. Antarctica is currently inhabited by about 14 species of freshwater crustaceans but recent climate changes and rapid warming of Antarctic Peninsula will probably lead to changes in the distribution of some species (e.g. Bockella poppei, Branchinecta gaini) that could, combined...
Legal regime of Antarctica with a special focus on the protection of the environment and the position of the Czech Republic
Přech, Ondřej ; Ondřej, Jan (advisor) ; Balaš, Vladimír (referee)
The objective of the thesis is to describe the legal regime of the Antarctic specifically in relation to the protection of its environment. The introductory chapters are devoted to brief description of the natural conditions of the Antarctic and the history of its exploration. In relation with the discovery voyages there are also mentioned the first territorial claims of the states and the legal foundations on which these claims were made. The author also deals with the basic legal document in relation to this continent, the Antarctic Treaty, mainly with its main principles as the demilitarization, prohibition of appropriation and the recognition of previous claims. Under the Antarctic Treaty several categories of the Parties to the Treaty can be distinguished which is an un-common situation. The existence of the Antarctic Treaty Consultative Meeting which is related to this situation is also being discussed. This Consultative Meeting further develops the principles of the Antarctic Treaty and issues Measures, Decisions and Resolutions. This thesis focuses on the analysis of the protection of the environment of the Antarctic. The topic has been divided into separate components of the environment and these are dealt with in individual chapters of the thesis where the steady development and the introduction...
Determination of mercury and methylmercury in specific Antarctic soils in surroundings of seal carcasses
Zvěřina, O. ; Kuta, J. ; Coufalík, Pavel ; Komárek, J.
This work is dealing with the determination of total mercury and methylmercury in specific Antarctic soils, which occur in the surroundings of seal carcasses.
Determination of methylmercury in lichens and cyanobacterial mat by GC-AFS
Coufalík, Pavel ; Meszarosová, N. ; Coufalíková, K. ; Zvěřina, O. ; Komárek, J.
The aim of this research was a development of the analytical method suitable for the determination of trace concentration of methylmercury in the ecosystem of Antarctic lakes. The determination of mercury bioaccumulation in cyanobacterial mat (the colonies of algae and cyanobacteria) stands in focus as well.
Testing of polymeric materials under climatic conditions of Antarctica
Mičkal, Petr ; Halavínová, Michaela (referee) ; Krmíček, Lukáš (advisor)
The bachelor's thesis generally deals with polymer materials and evaluates the possibility of testing their resistance to extreme climates of Antarctica. Described herein are various polymer materials, their characteristics, structure, properties and more thorough and detailed descriptions of selected polymers. The next section describes the basic types of degradation these polymers are exposed to, when facing the extreme conditions of the Antarctic climate. The practical part contains evaluations of tests made on the degraded polymer materials that were collected in Antarctica during the southern Antarctic season of 2013-2014 by Ing. Bc. Pavel Kapler, Ph.D, who is a superintendent at the Czech scientific station JG Mendel.

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