Search for dissertations about: "Ekologisk botanik."

Showing result 1 - 5 of 65 swedish dissertations containing the words Ekologisk botanik..

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

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

    Abstract : 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. READ MORE

  4. 2. Recruitment and understorey herb dynamics in deciduous and mixed coniferous forest

    Author : Heléne Fröborg; Mikael Ohlson; Stockholms universitet; []
    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

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

    Author : Einar Hörnström; Eva Willén; Stockholms universitet; []
    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

  6. 4. Island biogeography of young land uplift islands - viewed through the lens of bryophytes in a northern Swedish archipelago

    Author : Andreas Karlsson Tiselius; Mats Dynesius; Roland Jansson; Göran Englund; Joakim Hjältén; Tord Snäll; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; functional data analysis; metacommunity; isolation; mosses; liverworts; sporophyte production; dispersal-establishment trade-off; ekologisk botanik; Ecological Botany; Conservation Biology; naturvårdsbiologi; Statistics; statistik;

    Abstract : Increasing habitat fragmentation and rapid global warming is changing the conditions for species populations and ecological communities around the world. This presents challenges for the maintenance of biodiversity and a dominant paradigm for conservation in fragmented habitats is given by island biogeography and metapopulation (or metacommunity) ecology. READ MORE

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

    Author : Katariina Kiviniemi; Pedro Jordano; Stockholms universitet; []
    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