Sökning: "Plant ecology"

Visar resultat 31 - 35 av 371 avhandlingar innehållade orden Plant ecology.

1. 31. Herbivory and plant community structure in a subarctic altitudinal gradient

   Författare :Jon Moen; Nancy Huntly; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; arctic and alpine vegetation; competition; exclosures; lemmings; plant defences; plant-plant interactions; Ranunculus glacialis; snow-bed; structuring factors; tall herb meadow; vertebrate grazing; voles;

   Sammanfattning : The object of this thesis was to study plant community structure, especially in relation to vertebrate herbivory, in an altitudinal gradient in the Fennoscandian mountain chain.A sowing experiment in a high alpine Ranunculus glacialis population showed that seeds germinated better in cleared microsites than under established individuals. LÄS MER

3. 32. Small-scale pattern and mobility of plant species in Alvar grassland

   Författare :Xiaobing Dai; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; association analysis; cattle dung; decomposition; limestone grassland; Gland; PASFRAN; soil seed bank type; Sweden; turn-around time; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : Studies of the small-scale pattern, mobility of plant species and the effects of cattle dung deposition and decomposition on the soil seed banks and the above-ground vegetation were carried out in an alvar limestone grassland in Gettlinge, on the Baltic island of Öland, Sweden.A new method for pattern detection using transect data Patch Size Frequency Analysis (PASFRAN), was developed. LÄS MER

4. 33. Temperature and the synchrony of plant-insect interactions

   Författare :Tenna Toftegaard; Johan Ehrlén; Karl Gotthard; Christer Wiklund; Annette Menzel; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Brassicaceae; Anthocharis cardamines; climate change; development; oviposition; phenology; species interactions; herbivory; synchrony; timing; phenotypic plasticity; local adaptation; Plant Ecology; växtekologi;

   Sammanfattning : Increasing temperatures resulting from climate change have within recent years been shown to advance phenological events in a large number of species worldwide. Species can differ in their response to increasing temperatures, and understanding the mechanisms that determine the response is therefore of great importance in order to understand and predict how a warming climate can influence both individual species, but also their interactions with each other and the environment. LÄS MER

5. 34. Soluble and Plant Available Phosphorus in Acid Soils

   Författare :Ann-Mari Fransson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; solubilisation mechanisms; Phosphorus extractions; Oxalate extraction; P fertilisation; Plant ecology; Växtekologi;

   Sammanfattning : The P availability and solubility differ between soils and plants seem to have different ways of utilising the P present. The many P fractions present in soil interact and are closely related to another and transformations may easily occur. Due to this more P than the soluble fraction is available to plants. LÄS MER

7. 35. Recruitment ecology and fungal interactions in mycoheterotrophic Ericaceae

   Författare :Veronika A. Johansson; Ove Eriksson; Andrew Taylor; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; 454 Pyrosequencing; Dispersal limitation; Dust seeds; Ectomycorrhiza; Ericaceae; Microsite limitation; Monotropa hypopitys; Mycoheterotroph; Pyroleae; Seed limitation; Stable isotopes; Subterranean seedling; Symbiotic germination; Tricholoma; Plant Ecology; växtekologi;

   Sammanfattning : There are generally two contrasting alternatives to what limits recruitment in plants, namely the availability of seeds (seed limitation) or the quality or quantity of suitable sites (microsite limitation). Dust seeds, the smallest existing seeds, lack or have minimal nutrient reserves. LÄS MER