Sökning: "ekologisk botanik"

Visar resultat 1 - 5 av 67 avhandlingar innehållade orden ekologisk botanik.

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

    Författare :Heléne Fröborg; Mikael Ohlson; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Ecological Botany; ekologisk botanik;

    Sammanfattning : 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. LÄS MER

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

    Författare :Einar Hörnström; Eva Willén; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Ecological Botany; ekologisk botanik;

    Sammanfattning : 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. LÄS MER

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

    Författare :Katariina Kiviniemi; Pedro Jordano; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Ecological Botany; ekologisk botanik;

    Sammanfattning : 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. LÄS MER

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

    Författare :Åke Strid; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Basidiesvampar; ekologisk botanik; Ecological Botany;

    Sammanfattning : 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. LÄS MER

  5. 5. Reproductive patterns of birches (Betula spp.) in northern Sweden

    Författare :Stig-Olov Holm; Umeå universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Reproduction; Betula; seed-quality; seed-set; pollination; pollen-limitation; pollen-competition; tree-line; environmental gradient; seed weight; seedling survival; Semudobia;

    Sammanfattning : The aim of this thesis was to study patterns of reproduction of Betula pendula and B. pubescens coll. along an altitudinal, coastal-inland, gradient in northern Sweden. The altitudinal variation was related to the distribution of the birch taxa along the gradient. LÄS MER