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Holocene Succession of Mollusc Assemblages in the Southern Part of Kokořínsko Area
Oravec, Jan ; Juřičková, Lucie (advisor) ; Beran, Luboš (referee)
The sandstone rock cities of the Bohemian Cretaceous Basin are traditionally considered floristically and faunistically impoverished areas, because the environment of acidic quartz sandstones complicates the development of developed biocenoses. The unfavourable abiotic conditions are compensated for geomorphological diversity of the landscape, which creates a wide range of locations providing habitats for many biological species with different ecological requirements. However, the current appearance of the sandstone areas is due to the extensive transformation of the environment in the late Holocene, as evidenced by the rich subfossil communities of terrestrial gastropods. In the presented study, the succession of postglacial malacocenoses was processed from five sites in the southern part of the Kokořínsko area, demonstrating the continuous development of species-rich forest habitats during the early and middle Holocene. The presence of calcareous encrustations on the surface of acidic sandstone walls, which allowed the continuous occurrence of calciphilous mollusc species, is also documented from this wet period. The gradual transformation of the natural environment is related to the beginning of the late Holocene and was caused by the leaching of nutrients from the soil horizons and the...
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Quaternary insects and their significance for zoogeography, paleoclimatology and paleoecology
Moudrý, Jakub ; Prokop, Jakub (advisor) ; Říhová, Dagmar (referee)
The present thesis is a review of available published data on Quaternary insects. Research focused on Quaternary insects has been so far overlooked by the Czech scientists, even though there is potential to provide additional data for complex reconstruction of Quaternary deposits. Insect faunas allow to trace the dynamic development of areas across continents and serve for example as proof of migration routes. It is especially true for the Pleistocene, well known for prominent climatic oscillations. Thus, the insect species served as climatic indicators allowing estimations of average temperatures by application of the MCR method. Finally, these faunal changes reflect dynamic development of palaeoenvironments. The fact that the subfossil taxa correspond to the recent species allows broader reconstruction of the Quaternary deposits.
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Upper Turonian and lower Coniacian calcareous nannoplankton stratigraphy in the borehole V 800 Střeleč, Bohemian Cretaceous Basin
Svobodová, Andrea ; Švábenická, Lilian (advisor) ; Ozdínová, Silvia (referee)
Upper Turonian and Lower Coniacian calcareous nannoplankton stratigraphy in the borehole V 800 Střeleč, Bohemian Cretaceous Basin Number of biostratigraphic studies has been performed within the Upper Cretaceous platform sediments of the NW Europe, however, the problem of Turonian-Coniacan boundary has not yet been satisfactorily resolved using available methods in the field of micropaleontology. The proposed thesis has described the species composition of calcareous nannoplankton assemblages in the Bohemian Cretaceous Basin, across the Upper Turonian- Lower Coniacian interval, focusing on the stratigraphically and paleoecologically important species. Seventy-three taxa of calcareous nannofossils in the studied material have been determined and signifiant species have been discussed (Marthasterites furcatus, Kamptnerius magnificus, Lucianorhabdus sp., Braarudosphaera sp., Nannoconus sp., Watznaueria barnesae, Uniplanarius gothicus, Quadrum gartneri, Thoracosphaera operculata). For purposes of this thesis, a suitable material from the V 800 Střeleč borehole, one of the key cretaceous profil in the Český ráj area, was obtained.
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Selected cephalopods from the Ordovician of the Prague Basin (Bohemia) and Baltica (Estonia and Sweden): taxonomy, paleobiogeography and paleoecology
Aubrechtová, Martina ; Košťák, Martin (advisor) ; Klug, Christian (referee) ; King, Andrew H. (referee)
This dissertation thesis is a summary of five studies published in peer- reviewed, impacted scientific journals. All of the publications are taxonomic revisions of previously unknown or little known collections of fossil cephalopods from the Early Paleozoic strata of Bohemia, Estonia and Sweden. Paleogeogra- phical and stratigraphical distributions of the respective taxa were summarized, refined and compared with contemporary fossil assemblages known from other regions. Implications on the paleoecology of the cephalopods and original envi- ronmental conditions were made. The text of the thesis is divided into three main parts. In the first part, the morphology of cephalopods is explained, stressing out the most important diagnostic characters used for their descriptions. The current systematics of the Cephalopoda is overviewed and the main cephalopod groups during the Ordovician are briefly introduced. The second part of the thesis describes the geological development and settings of the regions, from which the studied fossil cephalopods originate. The third and final part of the thesis provides a discussion and interpretation of the results of the published studies in the context of the previously published research. The genus Bactroceras Holm, 1898 and some members of the order Litui- tida were studied...
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Subfossil Cladocera as a powerful tool for paleoecological reconstruction
Bubenková, Anna ; Tátosová, Jolana (advisor) ; Kopalová, Kateřina (referee)
This bachelor thesis is a literature review documenting the usage of subfossil Cladocera in paleoecological reconstruction. Its aim is to argue for subfossil Cladocera as an effective means of studying historical evolution of lakes and identifying significant processes which formed them over time. Furthemore, this literature review critically evaluates some of the most common approaches to reconstructing changes in climate, water levels, acidification, and eutrophication, and numerous issues they often encouter. The correct interpretation is vital because all the factors in the aquatic environment are connected. Despite some debate, subfossil Cladocera are an important aspect of paleoecological reconstructions with much possible utilization in future research. Key words: subfossil Cladocera, paleoecology, reconstruction
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Palaeoenvironmental reconstruction of the Younger Dryas based on subfubfossil cladocera
Bubenková, Anna ; Tátosová, Jolana (advisor) ; Vrba, Jaroslav (referee)
5 ABSTRACT Long-term paleoenvironmental reconstructions provides essential interpretation of environmental changes. Multiproxy analysis of lake sediments can be used for tracking the historical evolution of lakes and significant processes which formed them over time. Subfossil Cladocera play a key ecological role in freshwater ecosystems. Sedimentary cladoceran assemblages reflect environmental changes and exhibit great potential in past environmental reconstructions. The purpose of this diploma thesis is to identify climatic changes of the time interval between the Late Glacial and the early Holocene in Černé Lake. Based on the analysis of geochemical and biological proxies, determined climatic conditions of Younger Dryas (YD). The YD oscillation in Central Europe has only been briefly described. The Czech Republic is positioned between oceanic and continental climate. The results of the multiproxy analyses suggests that climate conditions of the region during YD were similar to Western Europe with moderate wet climate conditions during the first half and drier conditions during the second half of the period. In the middle of YD there was an interesting event. Observed, probably due to high precipitation and floods. These results are based on P/L ratio, geochemical proxies, pollen analyses and record of...
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Semiquantitative study of the fossil association of the Dobrotivá Formation (Ordovician, Prague Basin) in Ejpovice
Luptáková, Monika ; Kraft, Petr (advisor) ; Mergl, Michal (referee)
The master thesis is focused on the semiquantitative study of the fossil association of the stratigraphically lowest layer No. 3 from the channel sample from the Ejpovice locality, where in the southern bank of the flooded quarry, the Dobrotivá Formation of the Ordovician of the Prague Basin is exposed in the thickness of several meters. The thesis briefly summarizes basic knowledge about the fossil associations of the Dobrotivá Formation, its lithology, stratigraphy and previous paleontological research at studied locality. Paleoecology of the fauna recorded in studied material is described. The main part of the thesis is focused on the taphonomy and associations of the fossils recorded in studied material. In the final part of the thesis, the overall fossil association is characterized depending on the paleoecology and taphonomy of preserved fossils, and the model of the paleoenvironment at the Ejpovice locality is discussed. Based on the lithology and studied fossil associations, it is assumed that a dysoxic environment with episodic currents prevailed in the Ejpovice locality. The fauna is species-depleted and taxa typical of the Dobrotivá Formation are rare. The fauna is mainly allochtonous and most of the organisms are considered as postmortal accumulations in this study. Key words:...
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Long-term disturbances in temperate mountain forests and their representation in various proxy data
Pavlišová, Adéla ; Kuneš, Petr (advisor) ; Moravcová, Alice (referee)
In this work, I present the main disturbance agents affecting temperate mountain forests in Central Europe - wind, bark beetles and fires, and I draw attention to their interdependence. I primarily deal with the description of disturbances, their consequences, ecological contribution, and climate influence on their action. With climatic warming, the extent, intensity, and frequency of disturbances increase. Hence, it is important to understand their role in the past to prepare for the future development of our forests. Proxy data (indirect data) provide past evidence for disturbances, but their interpretation value differs. They inform us about a different time and spatial scale with varying degrees of accuracy. All the methods that I mention in my work provide us, to some extent, with climate proxy data that is closely related to the disturbance regime. Only some directly prove the disturbance, for example, through sedimentary charcoals findings. My work aimed at indicating possible complications but also the advantages that arise when combining individual methods.
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Geochemical markers from foraminiferal tests as a tool for reconstruction of paleoceanological environments: a case study from the Miocene of the Central Paratethys
Scheiner, Filip
This thesis deals with the use of geochemical proxies on foraminifera for paleoceanographical, paleoecological and paleoenvironmental interpretations in the fossil epicontinental sea - the Central Paratethys during the Langhian. It discusses the used methodologies and approaches that were specially chosen to fit the problematic of the studied area such as the single test analysis of carbon and oxygen stable isotopes on foraminifera. Other geochemical methods were represented by Mg/Ca based paleothermomethry and by several organic geochemistry proxies on whole rock samples (n-alkane indices, δ13 Corg, and carbon ratios - TOC/TIC/TC). These were further combined with foraminiferal paleoecological data, which allowed identification of particular water masses in the studied region as well as the prevailing circulation patterns/regimes during the studied interval in the Paratethyan marine realm. Additionally, there were interpreted various regional paleoenvironmental and paleoecological consequences. The Paratethys had similar hydrography of surficial waters with the Mediterranean, conversely to the bottom waters that were different, probably of a regional origin with their own evolution during the studied time interval. The anti-estuarine circulation regime, which was probably linked with the closure...
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Palaeoenvironmental reconstruction of the Younger Dryas based on subfubfossil cladocera
Bubenková, Anna ; Tátosová, Jolana (advisor) ; Vrba, Jaroslav (referee)
5 ABSTRACT Long-term paleoenvironmental reconstructions provides essential interpretation of environmental changes. Multiproxy analysis of lake sediments can be used for tracking the historical evolution of lakes and significant processes which formed them over time. Subfossil Cladocera play a key ecological role in freshwater ecosystems. Sedimentary cladoceran assemblages reflect environmental changes and exhibit great potential in past environmental reconstructions. The purpose of this diploma thesis is to identify climatic changes of the time interval between the Late Glacial and the early Holocene in Černé Lake. Based on the analysis of geochemical and biological proxies, determined climatic conditions of Younger Dryas (YD). The YD oscillation in Central Europe has only been briefly described. The Czech Republic is positioned between oceanic and continental climate. The results of the multiproxy analyses suggests that climate conditions of the region during YD were similar to Western Europe with moderate wet climate conditions during the first half and drier conditions during the second half of the period. In the middle of YD there was an interesting event. Observed, probably due to high precipitation and floods. These results are based on P/L ratio, geochemical proxies, pollen analyses and record of...
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