Sökning: "seedlings"

Visar resultat 16 - 20 av 114 avhandlingar innehållade ordet seedlings.

1. 16. Spatial Variation in Near-Ground Radiation and Low Temperature - Interactions with Forest Vegetation

   Författare :Kristina Blennow; Institutionen för naturgeografi och ekosystemvetenskap; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; light interception; hemispherical photograph; growth; forest fragmentation; fluorescence; cold-induced photoinhibition; GIS; view factor; radiative cooling; frost protection; agro-climatic mapping; forest clear-cut; local climate; Microclimate; Physical geography; geomorphology; pedology; cartography; climatology; Fysisk geografi; geomorfologi; marklära; kartografi; klimatologi;

   Sammanfattning : Low temperature has a large impact on the survival and distribution of plants. Interactive effects with high irradiance lead to cold-induced photoinhibition, which may impact on the establishment and growth of tree seedlings. LÄS MER

3. 17. The nitrogen economy of mountain birch : As related to environmental conditions and genotype

   Författare :Martin Weih; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Betula pubescens ssp. czerepanovii; growth; nitrogen; subarctic; temperature; ultraviolet radiation; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Sammanfattning : Responses of mountain birch growth to changed environmental conditions arestrongly affected by birch genotype, and nitrogen economy is a key factor influencingthe winter survival of first-year seedlings. These are some of the findings of a series ofstudies, in which growth, nitrogen economy and winter survival were analysed usingpot-grown seedlings of mountain birch (Betula pubescens ssp. LÄS MER

4. 18. Consequences of bushmeat hunting in tropical forests

   Författare :Edu Efiom; Biodiversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Tropical rainforests; bushmeat hunting; primates; seedling recruitment; interseedling competition; community composition; functional traits; ecosystem services; human livelihoods;

   Sammanfattning : This thesis evaluates the effect of bushmeat hunting in southeastern Nigerian rainforests on: 1) adult tree, seedling, and animal community compositions 2) germination and survival among seedlings in association with competition 3) changes in community composition at multiple trophic levels 4) leaf nitrogen concentration (LNC), leaf mass per area (LMA) and stem specific density (SSD) 5) on human reliance on forest resources and rural people use forest resources. Data for the first four evaluations were obtained from surveys, manipulative experiments in seedling plots and collected leaf samples in three pairs of sites with high (hunted sites) and low (protected sites) hunting pressure but with similar adult tree composition. LÄS MER

5. 19. Secondary metabolites associated with plant disease, plant defense and biocontrol : studies of Hymenoscyphus pseudoalbidus, Fraxinus excelsior and Pseudomonas brassicacearum MA250

   Författare :Pierre Andersson; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Secondary metabolites of the fungal ash dieback pathogen Hymenoscyphus pseudoalbidus were investigated. Nine steroidal compounds were isolated from, or detected in, liquid cultures of the fungus. Three were the previously known compounds viridiol, viridin and demethoxyviridiol. LÄS MER

7. 20. From growth cessation to bud burst : conifer seedling development in response to nursery culture and environmental stimuli

   Författare :Elisabeth Wallin; Högskolan Dalarna; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Picea abies; Pinus sylvestris; Pseudotsuga menziesii; seedling status; gene activity; photoperiod; storability; vitality; transplants; shoot electrolyte leakage; Picea abies; Pinus sylvestris; Pseudotsuga menziesii; plantstatus; genaktivitet; fotoperiod; lagringsbarhet; vitalitet; omskolningsplantor; elektrolytiskt läckage; Energy and Built Environments; Energi och samhällsbyggnad;

   Sammanfattning : In Sweden, 350-400 million seedlings are produced annually for forest regeneration. About one third of these are overwintered in frozen storage, necessitating accurate methods to assess storability. Young transplants of Norway spruce (Picea abies (L.) Karst. LÄS MER