Sökning: "lichen growth"

Visar resultat 1 - 5 av 15 avhandlingar innehållade orden lichen growth.

  1. 1. Modeling lichen performance in relation to climate : scaling from thalli to landscapes

    Författare :Anna V Jonsson Čabrajić; Kristin Palmqvist; Jon Moen; Per-Anders Esseen; Mikaell Ottosson-Löfvenius; Göran Ågren; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lichen; growth; model; micro-climate; hydration; activation; photosynthesis; respiration; Terrestrial ecology; Terrestisk ekologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : Lichens can colonize nearly all terrestrial habitats on earth and are functionally important in many ecosystems. Being poikilohydric, their active growth periods are restricted to periods when the thallus is hydrated from atmospheric water sources, such as rain, fog and high relative humidity. LÄS MER

  3. 2. Oral lichen planus : studies of factors involved in differentiation, epithelial mesenchymal transition and inflammation

    Författare :Karin Danielsson; Karin Nylander; Ylva Britt Wahlin; Linda Boldrup; Jesper Reibel; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; oral lichen planus; differentiation; inflammation; autoimmune; premalign; odontologi; Odontology; patologi; Pathology;

    Sammanfattning : Background: Lichen planus is a chronic inflammation of skin and mucosa with unknown cause. Oral Lichen Planus, OLP, affects around 2% of the population. Autoimmunity has been suggested as a possible cause as the disease has autoimmune features such as female predominance, cyclic nature and cytotoxic T-cell infiltrate. LÄS MER

  4. 3. Epiphytic lichen responses to nitrogen deposition

    Författare :Otilia Johansson; Kristin Palmqvist; Johan Olofsson; Annika Nordin; Lars E Ericson; Peter Crittenden; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lichens; air pollution; nitrogen deposition; phosphorus; growth; chlorophyll a; boreal forest; field experiment; irrigation; carbon based secondary compounds; Lavar; luftföroreningar; alg; svamp; kväve; fosfor; skog; Terrestrial ecology; Terrestrisk ekologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : Nitrogen (N) deposition has increased globally over the last 150 years and further increase is predicted for the future. Nitrogen is an important nutrient for lichens, involved in many processes in both photobiont and mycobiont.  However, N can be a stressor, causing many lichens and lichen communities to disappear with increased deposition. LÄS MER

  5. 4. Resource aquisition and allocation in lichens

    Författare :Lena Dahlman; David Richardson; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Amino acid; Arginine; carbohydrates; chlorophyll; ergosterol; microclimate; Lichen growth; nitrogen stress; photosynthesis; proteins; respiration; Symbiosis lichen ; nitrogene uptake; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : Lichens are fascinating symbiotic systems, where a fungus and a unicellular alga, most often green (bipartite green algal lichens; 90% of all lichens), or a fi lamentous cyanobacterium (bipartite cyanobacterial lichens; 10% of all lichens) form a new entity (a thallus) appearing as a new and integrated organism: in about 500 lichens the fungus is associated with both a cyanobacterium and an alga (tripartite lichens). In the thallus, the lichen bionts function both as individual organisms, and as a symbiont partner. LÄS MER

  7. 5. Forest edges in boreal landscapes - factors affecting edge influence

    Författare :Ulrika Jansson; Per-Anders Esseen; Mats Nilsson; Timo Kuuluvainen; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; aerial photographs; edge contrast; edge density; edge length; fetch size; forest fragmentation; lichen growth; line intersect sampling; pendulous lichen; photo interpretation; skogskant; flygbild; kantlängd; lav; Terrestrial ecology; Terrestisk ekologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : The boreal forest in Fennoscandia has been subjected to major loss and fragmentation of natural forests due to intensive forestry. This has resulted in that forest edges are now abundant and important landscape features. Edges have documented effects on the structure, function and biodiversity in forests. LÄS MER