Sökning: "plant fossils"

Hittade 4 avhandlingar innehållade orden plant fossils.

  1. 1. Comparative morphological studies of fossil and living plane trees (Platanaceae) and oaks (Quercus): taxonomy, ecology, evolution

    Författare :Georg Florian Tschan; Thomas Denk; Ove Eriksson; Bertil Ståhl; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Platanaceae; Platanus; Credneria; Quercus; Galliferae; leaf architecture; epidermal anatomy; comparative morphology; character variation; variability; sample size; diversity patterns; species concepts; ecology; biogeography; evolution; plant fossils; Plant Ecology; växtekologi;

    Sammanfattning : Morphological characters are essential for flowering plant identification, but also provide information about diversity patterns and ecological adaptation. In woody plant species, characters of the leaf are among the most useful and can be examined on fossils as well. LÄS MER

  2. 2. Event stratigraphy for the Last Glacial-Holocene transition in eastern middle Sweden

    Författare :Jonas Björck; Michael J.C Walker; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Last Glacial-Holocene transition; event stratigraphy; eastern middle Sweden; pollen; plant macrofossils; marine calcareous fossils; microtephra; radiocarbon dating; clay varve chronology; GRIP; ice-core chronology; calendar year chronology; Preboreal oscillation; Yoldia Sea; Baltic Ice Lake; Quaternary Geology; kvartärgeologi;

    Sammanfattning : This thesis outlines an event stratigraphy for the Last Glacial-Holocene transition in eastern middle Sweden. Events are short-lived occurrences that have left traces in the geological record and which, therefore, may be used for correlation and inter-regional comparisons. LÄS MER

  3. 3. Phylogeny of Selaginellaceae

    Författare :Petra Korall; Birgitta Bremer; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Plant physiology; Växtfysiologi; fysiologisk botanik; Physiological Botany;

    Sammanfattning : The phylogeny of Selaginellaceae, a small, but historically important family of heterosporous lycopods, has been the focus of this thesis. The approximately 700 extant species are herbaceous and distributed all over the world, with most species in the tropics and subtropics. LÄS MER

  4. 4. Early land plant spores from the Paleozoic of Sweden – taxonomy, stratigraphy and paleoenvironments

    Författare :Kristina Mehlqvist; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Spores; early land plants; taxonomy; stratigraphy; biostratigraphy; Silurian;

    Sammanfattning : The Silurian through earliest Devonian, between ca 444 and 412 million years ago, was characterized by significant changes in global climate and environment. At that time, plants and animals had begun to expand the colonization of previous relatively desolate terrestrial landscape. LÄS MER