Search for dissertations about: "Ekologisk botanik"

Showing result 1 - 5 of 56 swedish dissertations containing the words Ekologisk botanik.

  1. 1. Recruitment and understorey herb dynamics in deciduous and mixed coniferous forest

    University dissertation from Stockholm : Department of Botany, Stockholm University

    Author : Heléne Fröborg; Mikael Ohlson; [2001]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecological Botany; ekologisk botanik;

    Abstract : The distribution and abundance of plant species is determined by the ability to disperse, recruit and persist in a suitable habitat. Plant-animal interactions influence recruitment by reducing seeds and seedlings through predation and herbivory. READ MORE

  2. 2. Phytoplankton in Swedish oligotrophic lakes, affected by acidification, metals and liming

    University dissertation from Stockholm : Stockholm University

    Author : Einar Hörnström; Eva Willén; [1999]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecological Botany; ekologisk botanik;

    Abstract : Anthropogenic airborne acidification has seriously affected thousands of lakes in Sweden, an alarming fact which was first noticed in the early 1970s, when pH had decreased to values below 5, especially in areas poor in limestone such as the Swedish west coast. This development was critical to phytoplankton, the diversity of which being markedly reduced, and where the groups Cyanophyceae, Bacillariophyceae and Conjugatophyceae were totally eliminated. READ MORE

  3. 3. Evolution of seed attributes, dispersal and population dynamics of plants,with special emphasis on fragmented habitats

    University dissertation from Stockholm : Stockholm University

    Author : Katariina Kiviniemi; Pedro Jordano; [1999]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecological Botany; ekologisk botanik;

    Abstract : Theory predicts that life history traits that reduce the impact of environmental variation will exhibit a pattern of negative covariation (trade-offs). In plants, such traits are seed size, spatial seed dispersal and seed dormancy which interact to reduce risk in a variable environment. READ MORE

  4. 4. Wood-inhabiting fungi of alder forests in north-central Scandinavia 1, Aphyllophorales (Basidiomycetes). Taxonomy, ecology and distribution

    University dissertation from Stockholm : Stockholm University

    Author : Åke Strid; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Basidiesvampar; ekologisk botanik; Ecological Botany;

    Abstract : Wood-inhabiting fungi were collected on different trees in 99 loca-' lities of alder woods, dominated by Alnus incana or occasionally A. glutinosa, in N-C Sweden and C Norway. Most of the localities are situated near the east coast of Sweden where the prevailing land elevation creates conditions suitable for colonization by alder. READ MORE

  5. 5. Life History and Tolerance and Resistance against Herbivores in Natural Populations of Arabidopsis thaliana

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Reiko Akiyama; Jon Ågren; Arjen Biere; [2011]
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Arabidopsis thaliana; life history evolution; flowering time; germination; phenology; plant-herbivore interactions; natural selection; tolerance to leaf damage; resistance to herbivory; Plutella xylostella; Mamestra brassicae; Biology with specialization in Ecological Botany; Biologi med inriktning mot ekologisk botanik;

    Abstract : In this thesis, I combined observational studies with field and greenhouse experiments to examine selection on life history traits and variation in tolerance and resistance against herbivores in natural populations of the annual herb Arabidopsis thaliana in its native range. I investigated (1) phenotypic selection on flowering time and plant size, (2) the effects of timing of germination on plant fitness, (3) the effect of leaf damage on seed production, and (4) correlations between resistance against a specialist and a generalist insect herbivore. READ MORE