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Showing result 1 - 5 of 9 swedish dissertations matching the above criteria.
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1. The Greenhouse - Icehouse Transition : a dinoflagellate perspective
Abstract : Through the analysis of the stratigraphic and spatial distribution of organic walled dinoflagellate cysts (dinocysts) from climatologically and oceanographically key sites, this project aims to contribute to a better understanding of the Eocene-Oligocene (E/O) environmental changes and their timing. A central issue is to identify the global environmental changes which are responsible for the Eocene cooling and its underlying mechanisms with the focus on the Oligocene isotope-1 (Oi-1) event, thought to mark the onset of major Antarctic glaciation. READ MORE
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2. Dinoflagellate studies of the Upper Maastrichtian and Danian in southern Scandinavia
Abstract : Three Swedish borehole cores and three Danish outcrop sections, spanning the Upper Maastrichtian and Danian, have been analyzed for dinoflagellates. Variations in the relative abundances of certain dinoflagellate species have been used to establish a quantitatively defined, high-resolution zonation for the Upper Maastrichtian of southern Scandinavia. READ MORE
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3. Cretaceous dinoflagellate cyst stratigraphy of the Höllviken 1 well, Scania, Southern Sweden
Abstract : The main aim of this thesis was to develop an improved biostratigraphical subdivision for part of the Lower and Upper Cretaceous section (Albian to Santonian) of Scania, Southern Sweden. Earlier attempts at biostratigraphic zonation within the sequence Cenomanian to Coniacian based on other micro- and macrofossils have proven difficult due to an impoverished fauna. READ MORE
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4. The role of resting cysts in the survival and succession of freshwater dinoflagellates
Abstract : Phytoplankton have adapted to survive in the variable and heterogeneous environment that is characteristic of lakes in temperate regions. One strategy for survival during periods unfavorable for growth is to form resting propagules. READ MORE
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5. The significance of sexuality and cyst formation in the life-cycles of four marine dinoflagellate species
Abstract : Sexuality and cyst formation were studied in the marine dinoflagellate species Gymnodinium catenatum Graham, Gymnodinium nolleri Ellegaard ? Moestrup, Alexandrium catenella (Whedon et Kofoid) Balech, and Lingulodinium polyedrum (Stein) Dodge. The study included the morphological characterization of sexual stages and processes, the time and description of meiosis, the study of the length and regulation of the mandatory dormancy period of resting cysts, and the relationships among parental strains and cyst progeny at phenotypic and molecular levels. READ MORE