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Visar resultat 1 - 5 av 36 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. 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

  3. 2. Living on the edge : effectiveness of buffer strips in protecting biodiversity on boreal riparian forests

    Författare :Kristoffer Hylander; Christer Nilsson; Bengt Gunnar Jonsson; Ellen Macdonald; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; boreal forest; bryophyte; buffer strip; ecological boundary; edge effect; headwater stream; land snail; liverwort; moss; phytometer; riparian forest; substrate; terrestrial gastropod; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

    Sammanfattning : The objective of this thesis is to evaluate the ecological consequences of buffer strip retention on riparian and terrestrial biodiversity. Earlier studies on forest buffer strips have evaluated their effectiveness in relation to water quality and aquatic biota. However, forests along streams are species rich habitats for many organism groups. LÄS MER

  4. 3. Forest edge development : management and design of forest edges in infrastructure and urban environments

    Författare :Björn Wiström; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : This thesis investigates design guidelines and management systems for the development of stationary forest edges with a graded profile in infrastructure and urban environments. The spatial restriction for the edge to move forward caused by human land use counteracts the natural dynamics and development patterns of graded forest edges. LÄS MER

  5. 4. Forest restoration on degraded lands in Laos

    Författare :Sovu; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Deforestation and land-use change have been, and still are, major threats to biodiversity and ecosystem services in the tropics, and forest areas are being lost at high rates in many countries in Southeast Asia, including Laos. Progress in the development and application of forest policies and programs, coupled with increasing trends to end damaging practices associated with swidden cultivation have created opportunities to restore forests. LÄS MER

  7. 5. Improving boreal forest regeneration in a variable climate

    Författare :Bodil Häggström; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Regeneration of boreal forests in Sweden mainly involves planting Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) seedlings on clear-cut areas, although there is an increasing interest in planting broadleaves and in applying continuous cover forestry (CCF). LÄS MER