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Visar resultat 1 - 5 av 803 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Barriers and bridges for introducing agroforestry and community-based forestry among food insecure households in eastern Africa

    Författare :Karl-Erik Johansson; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : The aim of introducing agroforestry and community-based forestry is to secure and improve livelihoods, maintain and restore ecosystem services, and contribute to climate change mitigation and adaptation. However, the adoption and scaling up of these systems among food insecure communities have proved to be difficult. LÄS MER

  3. 2. Automation in forestry : development of unmanned forwarders

    Författare :Ola Ringdahl; Thomas Hellström; Tomas Nordfjell; Arto Visala; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Computer science; Datavetenskap; Forest engineering; Skogsteknik; computer and systems sciences; data- och systemvetenskap;

    Sammanfattning : For the last 50 year, forestry operations have become more and more mechanized. In modern forestry in Europe two machines are typically used; a harvester that fells, debranches and cross-cuts the trees into logs and a forwarder that transports them to the nearest road. LÄS MER

  4. 3. Ash Products for Nutrient Recycling in Forestry : Leaching and Drying Characteristics

    Författare :Peter Mellbo; Tommy Claesson; Sirkku Sarenbo; Hans Samuelsson; Högskolan i Kalmar; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Ash products; Wood ash; Leaching; Drying; Nutrient; ; Sustainable forestry; Forestry; Skogsskötsel; Miljövetenskap; Environmental Science;

    Sammanfattning : As the demand for carbon dioxide neutral energy sources increases, forestry becomes more intensive. Entire trees are removed from the felling sites threatening the nutrient balance of the forest soils. LÄS MER

  5. 4. Extraction of logging residues for bioenergy : effects of operational methods on fuel quality and biomass losses in the forest

    Författare :Bengt Nilsson; Johan Bergh; Gudmund Vollbrecht; Rolf Björheden; Linnéuniversitetet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Forest fuel; Storage; Fraction composition; Needles; Defoliation; Moisture content; Nutrients; Nitrogen; Norway spruce; Picea abies; Skogsbränsle; Lagring; Fraktionsfördelning; Barr; Avbarrning; Fukthalt; Näringsämnen; Kväve; Gran; Picea abies; Forestry and Wood Technology; Skog och träteknik;

    Sammanfattning : Wood products play a key role in the transformation to a more sustainable society based on renewable bio-based resources, together with the positive effects on climate mitigation by replacing fossil fuels. However, to increase the use of forest fuel in practice it is important to understand the effects of handling and storage on its quality and removal of nutrients from the forest. LÄS MER

  7. 5. Soil nitrogen fluxes and root uptake in the boreal forest : key processes to plant nitrogen nutrition

    Författare :Olusegun Ayodeji Oyewole; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Nitrogen (N) is essential for growth and net primary production of plants. However, N acquisition by plants is influenced by movement of soil N compounds from bulk soil to plant roots and uptake of N by roots. This thesis is aimed at deepening our knowledge on these key processes involved in plant N acquisition in the N-limited boreal forest. LÄS MER