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Postglacial vegetation history of local phenomena in western Bohemia
Švarcová, Markéta Gabriela ; Kuneš, Petr (advisor) ; Kozáková, Radka (referee)
In the sense of postglacial vegetation development, western Bohemia represents one of the least studied regions in the Czech Republic. This area, however, represents a supposed migration route of trees towards northern Europe during the Holocene. The most appropriate area for testing of such proposal might be western Sudetes with Slavkovský les protected landscape area in the Karlovy Vary region. Postglacial vegetation history was studied on the basis of two sedimentary profiles - from the fen bog near Číhanské prameny springs and from the vicinity of Mnichovské hadce serpentines from the nature reserve Mokřady pod Vlčkem. Percentual as well as influx diagrams were constructed on the basis of results of standard pollen analysis. Comparison of these results with the data from other suitable profiles enabled reconstruction of migration history of main tree taxa. The Číhaná profile reflects the period from the Older Dryas up to the Atlantic. The oldest Holocene forest was formed by the dominant Pinus, while Corylus was joining already in the Preboreal. Quercetum mixtum folowed in the begining of the Boreal and spruce quickly gained dominance in the Atlantic. The sedimentation process was probably finished due to rapid accumulation of sediments followed by spontaneous drainage ending with spruce and alder...
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Holocene history of Arctic lakes
Roman, Matěj ; Nývlt, Daniel (advisor) ; Kavan, Jan (referee)
Holocene history of Arctic lakes Abstract Palaeolimnology in the Arctic has achieved a considerable progress in the last decades. The Arctic has changed markedly since the Last Glacial and glacier retreats caused formation of a great number of diverse lake types. Lakes of glacial origin, thermokarst lakes, fluvial lakes and lakes on raised beaches occur most often here. Palaeolimnological methods applied to the high latitude areas are used for the study of the history of individual lakes. Methods of correlation of sedimentary cores and basic interpretation of proxy records such as magnetic susceptibility, diatom biostratigraphy and content of carbon and sulphur were applied on sediments of Garmaksla Lake, Svalbard Archipelago. Climatic and ecological shifts including the Little Ice Age termination and recent warming were registered in proxy values. Keywords: lakes, palaeolimnology, palaeoclimatology, environmental changes, Holocene, Arctic
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Dental phenotype variation in voles during the present glacial cycle
Putalová, Tereza ; Horáček, Ivan (advisor) ; Kuneš, Petr (referee)
The phenotype dynamics of arvicolid rodents during the terminal stages of the Vistualian glacial and the earliest Holocene was investigated with aid of a detailed morphometric analyses of extensive dental material from three sedimentary series of that age. The particular attention was paid to the record from a section in Býčí skála cave, Moravian karst, which demonstrated details of the Pleistocene/Holocene transition (12.4-8.4 ky BP) with extraordinary resolution. It revealed that dramatic rearrangements in community structure were accompanied by significant rearrangements of the phenotype dynamics in all arvicolid species. Despite some trends specific for particular species, some common features were identified as well. One of them was a rapid turnover in phenotype structure by the end of Younger Dryas, at time of the Preboreal event. (11.7-11 ky BP), the other was associated with the extensive shifts in community structure and habitat diversity at terminal stage of the Preboreal (9.7-9.3 ky). The core arvicolid species of Preboreal communities, Clethrionomys glareolus, Microtus arvalis, M.agrestis and Arvicola terrestris, exhibited repeated fluctuations during that stage (ll-9,3 ky BP) both in abundance and phenotype characteristics, supposedly related to serial invasion events during that time....
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History of vegetational development in the Cheb basin from sedimentary record of the SOOS National Nature Reserve
Suda, Tomáš ; Kuneš, Petr (advisor) ; Bešta, Tomáš (referee)
Vegetation development in the Cheb basin ( W Czech Republic) recorded in the sediments of the SOOS ational ature Reserve This thesis focuses on palaeoecological research of quaternary sediments in the Soos National Nature Reserve (Cheb basin, NW Czech Republic). Quaternary history of this locality is poorly known, despite it is a valuable and protected area with high natural qualities. The Soos basin is also known for its unique geological record, which is expected to cover information on landscape dynamics at least during the Holocene. A lake existed in the Soos basin enabling accumulation of diatomite and peat sediments of a broad palaeoecological potential. Records were analysed with method of pollen analysis and were dated using 14C. The results of this study bring information about vegetation development in the area of Cheb basin as well as development of lake ecosystem. It also gives a new insight on lake's origin and its age. The accumulation of peat sediments started in the Preboreal period and was continuous at least until the Atlantic following with a hiatus, therefore further detection of vegetation development is impossible. The beginning of diatomite accumulation, as well as the existence of the lake goes back to the Bølling interstadial, according to radiocarbon dating. However, this...
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Hamsters (Rodentia, Cricetinae) in the Quaternary fossil record of Czech Republic and Slovakia
Lebedová, Klára ; Horáček, Ivan (advisor) ; Wagner, Jan (referee)
1 Abstract The material of hamster remains in the Quaternary fossil assemblages from Czech Republic and Slovakia was analyzed in details with aid of biometric comparisons and contextual analyses focused on stratigraphic position of particular records and structure of the small mammals communities accompanying them. Cricetus as well as small hamsters (Allocricetus-Cricetulus) were recorded in all main Quaternary biozones (MN17-Q4). Yet Cricetus was recorded in few assemblages only mostly just with a single specimen only, except for several Q2 sites and those from the present glacial cycle (with peak abundance in preboreal and boreal). Despite obvious common trends (enlarging size from MN17 to Q3) all samples show roughly the same pattern of dental variation supporting a concept of Cricetus as a monotypic genus with a single species, C. cricetus covering all fossil forms separated as its subspecies. Correspondingly, our results support congeneric status of MN17-Q3 Allocricetus and Q4 Cricetulus, despite separating them as independent species, i.e., Cricetulus bursae and Cricetulus migratorius. Analysis of subrecent samples of C. migratorius from Turkey revealed a very broad span of phenotype variation in extant species covering both the variation framework of extant Phodopus sungorus and metric variation in a...
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Paleoenvironmental evolution around Lake Ohrid in the context of ancient settlement
Koubský, Karel ; Hošek, Jan (advisor) ; Abraham, Vojtěch (referee)
Lake Ohrid, the oldest lake in Europe, is an ideal place to study the response of the terrestrial ecosystems to many climatic and environmental changes during the Quaternary. It is also a useful source of information regarding the interactions between man and environment during the Holocene - this applies especially to the Late Bronze Age period and the beginning of the Iron Age, when there were profound changes in landscape management and when lakeside settlements were suddenly abandoned, which is also evident in the palaeobotanical record. This work summarizes the existing knowledge on this issue and presents various possibilities for studying paleoenvironmental development in this area. Key words: Holocene - Lake Ohrid - paleoenvironmental reconstruction - settlement - Bronze Age
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Genus Sicista (Mammalia, Rodentia) in the fossil record of central Europe: phenotypic variation, taxonomic structure, range dynamics.
Lišková, Tereza ; Horáček, Ivan (advisor) ; Vohralík, Vladimír (referee)
Member of the genus Sicista rank among the rarest and the least known European mammals. They exhibit a number of outstanding specificities (hibernation, aestivation etc.) and extreme capability of a rare range dynamics. Their fossil record is fragmentary and associated with numerous controversies. The present thesis summarizes results of a detailed revision of the fossil record of Sicista from Czech Republic, Slovakia and some other countries. It comprises of about 150 items of the Holocene and Vistualian age as well as from the Middle and Early Pleistocene including earliest records from MN17/Q1 boundary and type material of S. praeloriger from Q1 Betfia. Compared to a sample of extant population, variation dynamics of both metrical and nonmetrical dental traits was examined in details with particular attention to phenotype patterns of particular fossil samples. The results demonstrated extensive amount of both within- and between-population variation and rather limited validity of commonly used discrimination criteria of extant clades. Nevertheless, we succeeded in species identification of considerable part of numerous Holocene and Vistulian records which revealed (i) a range expansion of S. subtilis s.l. during MIS 3 with persistent distribution in lowland regions of Central Europe in the Late...
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Western Carpathians as diversity hotspot during the Quaternary climatic cycle
Kubíková, Kateřina ; Juřičková, Lucie (advisor) ; Horáček, Ivan (referee)
In the context of the entire Europe, the Western Carpathians is a unique area of priceless biological significance. Topological complexity, together with significant climatic and edaphic variability, is reflected in the high habitat heterogeneity and has enabled the survival of a large number of species in this area during the Quaternary climatic cycle. The Western Carpathians thus represents one of the most important glacial as well as interglacial refugium in Europe. The result of these environmental variables and the unique history of this region is an enormous species diversity, a high degree of endemism and the occurrence of many glacial relics. This bachelor's thesis contains a review of mainly zoological studies dealing with high biodiversity and degree of endemism in the Western Carpathians and its possible causes. The role of the Western Carpathians as an important Pleistocene refugium, its influence on other parts of Europe and the postglacial development of the area are discussed in individual chapters.
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Holocene fire history of forest vegetation in central Europe based on soil and sedimentary charcoal
Bobek, Přemysl ; Kuneš, Petr (advisor) ; Feurdean, Angelica (referee) ; Chytrý, Milan (referee)
Fire is a fundamental environmental factor that directly shapes many terrestrial ecosystems on Earth. The present thesis attempts to provide a comprehensive overview of the fire dynamics in Central Europe over the course of the last 12,000 years. Based on extensive analyses of charcoal particles deposited in terrestrial and lacustrine sedimentary sequences and carbonized plant tissues deposited in soils, I was able to track past fire dynamics across a range of spatial scales - from the forest stand scale to the landscape scale. First, we described relationships between drivers of recent fire occurrence and proposed linkages to the spatial pattern of Late-Holocene biomass burning. We found factors related to relief characteristics, such as increased thermal flux or terrain roughness, to be important determinants of fire occurrence within the present-day landscape. Contrary to all expectations, anthropogenic drivers seem to have a weak influence at present. Because relief-based factors have been stable throughout the Holocene, it seems probable that habitats of certain types are more predisposed to increased burning. We hypothesized that recurrent fire disturbances may contribute to the long-term maintenance of Pinus sylvestris-dominated forests, which withstood the competitive pressure of broadleaf...
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Holocene climate changes in the High Arctic
Prochová, Dominika ; Vondrák, Daniel (advisor) ; Roman, Matěj (referee)
Climatic changes are nowadays frequently discussed subject in the scientific, political and public sphere. For better understanding of their causes, development and possible impacts is one of the basic prerequisites for investigating such anomalies, that have taken place in the past. In natural archives, it is possible to find records not only about their parameters but also about the mentioned impacts - ecosystem changes, earth surface's geomorfological transformartions or the impact on human society. The most studied period of geological time is Holocene. It is about the most recent period and we currently live in its third stage. Thankfully, due to relatively sufficient knowledge of its climatic anomalies we are able to study the climate's contribution with enough complexity to valorize the currently much observed global warming, witch is often connected to human activity. The Arctic is probably the most sensitive place to climate changes on the planet. The warming, that is currently observed around the globe, is there noticeably higher - by the end of the 20th century, the average annual temperature increased twice as fast. The aim of this thesis is, in the form of literary research, to describe and examinatie the climate development in high Arctic areas, potencially the most sensitive...
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