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23 Uppsatser om Lichens - Sida 2 av 2

Sällskapet örtagårdens vänners trädgård i Vadstena : aktuellt växtinnehåll i historisk belysning och med sikt framåt.

Dead wood is important for many species. The amount of coarse dead wood (diameter >10 cm) is much lower in managed forest than in unmanaged forests. Stumps constitute the largest proportion of the volume of coarse dead wood in managed forests. Since stump harvest for biofuel may increase, the amount of dead wood will decrease even more, which may threaten biodiversity. The first aim of this study was to compare the amounts of fine woody debris (FWD, .

Environmental variables determining the occurrence of Cladonia parasitica and Hertelidea botryosa, two boreal lichens confined to wood

Biodiversity is essential for human well-being and it is defined as the genetic variation within species and the variety of species and ecosystems. Biodiversity provides several ecosystem services which are necessary for human beings but there are different threats towards the biodiversity. The biodiversity linked to the forest in Sweden are threatened, about 50 % of the red-listed species in Sweden are associated with forests. This is linked to the commercial exploitation of the boreal forest in Sweden which started 200 years ago. The forestry the last 50 years, with clear-cuts, have contributed to a fragmented forest landscape.

Jätteträd ? inventering, bevaring, skötsel samt rekrytering :

During the summer of 2007 I was employed by Högestad Christinehofs Förvaltning AB. My main task was to make an inventory of giant trees at the estate. Högestad and Christinehof,which with their total possession of 13 000 ha of land is the biggest estate in Scania. A giant tree is a tree with a diameter in breast height more then 1 meter. Trees of these dimensions are registered by Swedish authorities. Landowners with a giant tree on their property can receive a subsidy for cutting trees that are in competition with the giant tree.(Levenskog, 2007) Giant trees are important for biodiversity in the landscape and there are important habitats for different insects, birds, bats, Lichens and funguses.

Goliatmusseron (Tricholoma matsutake) - kräver den en kontinuitet av träd? :

Modern forestry management may disadvantage some mykorrhiza forming fungi because; they are dependent on late successions and cannot survive the constantly recurring breaks in the continuity of their host tree. For this study the specie goliatmusseron (Tricholoma matsutake) was chosen to investigate this possibility. In Sweden T. matsutake is found in greatest amounts north of Örnsköldsvik on glacifluvial sandy soils in association with pine trees and reindeer Lichens. Seventy two forest stands where the specie previously had been found were studied; 62 in the northern part of Sweden and ten in the southern. Several indicators were studied to find out if these stands have had a continuity of living trees.

Epixylic, forest-interior bryophytes in young stands : importance of local environmental variables, propagule sources, and distance to bordering woodland key habitats

The reduction of coarse, dead wood is considered to be the biggest threat to flora and faunain boreal forests. Extensive harvest of logging residues would increase this reduction evenmore. However, the role of dead wood created at final felling for boreal, epixylic species isstill largely unclear. It is therefore of interest to examine whether epixylic species inhabit thedead wood in young, boreal stands, especially species considered to be confined to forests inlate successional stages.The aim of this study was to investigate whether forest-interior species in fact can inhabitearly-successional forests arisen after logging. The study was conducted in young standsbordering dead wood rich woodland key habitats.

Naturvärdesbedömning av naturreservatet Blänkabacken, i Örebro kommun : Inventering av signalarter med fokus på mossor och lavar som indikerar höga naturvärden i skogsmiljöer.

I dag råder det brist på död ved i Sveriges skogar. Detta på grund av det intensiva skogsbruket där man kalhugger och plockar bort all liggande ved. Dock är det viktigt med många döda träd i olika nedbrytningsstadier för många skogslevande arter. Svenska skogar har få urskogar där naturliga avdödningsprocesser av träd får ske och därför minskar den biologiska mångfalden i skogen. Tre arter som endast trivs i naturskog är tickorna ullticka, Phellinus ferrugineofuscus, gränsticka, Phellinus nigrolimitatus och vedticka, Phellinus viticola.

Trädslagsinverkan på markvegetationens utveckling i odlingsförsök med tall och contorta :

In the 1970?s it was predicted that in the beginning of the 21st century there would be a timber shortage in Sweden and a large scale introduction of the exotic tree species lodgepole pine started. An introduction of a foreign tree species means a risk of a negative influence on the forests ecosystem. Today, the stands that were established in the 70?s are middle-aged and the effect on the forest floor vegetation can be studied.

Bevarande av hotade epifytiska lavar och vedsvampar i Norrbottens län : rödlistan som verktyg i praktisk naturvård

Många arter påverkas idag negativt av skogsbruket. Detta visar sig dels i ett växande antal arter på den svenska Rödlistan. I Norrbottens län är idag närmare 500 skogslevande arter rödlistade, och dessa är fördelade över flera olika organismgrupper. Det stora antalet rödlistade arter i skog innebär att det är svårt att direkt utifrån Rödlistan utforma effektiva naturvårdsåtgärder samt generell hänsyn inom skogsbruket. Genom att sammanställa och strukturera information om de rödlistade arternas krav på livsmiljö och hotsituation kan Rödlistan som verktyg utvecklas.

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