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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...
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Aspects of the high latitude environments in Cretaceous and Paleogene with special respect to land plants
Chernomorets, Oleksandra ; Sakala, Jakub (advisor) ; Dašková, Jiřina (referee)
This work is focused on the problematics of high latitudes in Cretaceous and Paleogene. The introduction describes and defines high latitude regions as well as their main characteristics nowadays. This allows one to achieve a better understanding of the substantial differences of these regions nowadays and in the geological past. The work itself then provides a brief description of the palaeographic position of the Arctic and Antarctic regions, their palaeoclimatic situations, organisms inhabiting their terrestrial and marine environments and their adaptation mechanisms. Further, a more detailed review of the land plants is presented. The last part is dedicated to the specific survival strategies of the land plants in the polar regions during the warm geological periods. On the basis of the studied literature, this work attempts to answer the questions: which strategy for adaptation to the high latitudes was used by the plants and whether being evergreen or deciduous was more effective on survival during the long and relatively warm polar nights. In conclusion, the relevance of the research of high latitude regions during the Cretaceous and Paleogene greenhouse type of climate is introduced in relation to the possible future consequences of the global warming. Key words: Cretaceous, Paleogene, land...
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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...
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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...
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Physical Phenomenon as a Creative Method in Architecture
Buryová, Tereza ; Mach, Jan (referee) ; Kristek,, Jan (advisor)
Cellular_ polar research station Antarctica is the driest, the busiest and most extensive place on Earth, half-year-shrouded. People still live here. They set up the research stations in which they live and work. In these extreme climatic conditions, the station originates and disappears due to natural behaving. Stations provide researchers with safety and space for research, including comfort. They are built in different ways and provide different comforts, according to technological and transport options.
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Testing of polymeric materials under climatic conditions of Antarctica
Mičkal, Petr ; Sluková, 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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Development and functioning of the Antarctic Treaty System
Špotová, Jana ; Kochan, Jan (advisor) ; Tůmová, Jana (referee)
The aim of this work is to evaluate effectiveness of operation of the Antarctic Treaty System and to identify main problems which have appeared during half-century of its existence. In the introductory part of this work I describe the history of formation of the Antarctic Treaty System with focus on development of territorial claims in relation to Antarctica. In another part, the attention is payed to key provisions of the Antarctic Treaty, which is the essential document of the whole system. I also describe two chosen bodies of the system and with the use of their example the principles of functioning of the whole system are illustrated. The last part deals with those controversial points of the system, which are relevant in the present day and which might be important in the future as well.
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