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1026 Uppsatser om Dead wood qualities - Sida 2 av 69

Environmental variables determining the occurrence of the red-listed Carbonicola anthracophila and C. myrmecina in boreal forests

The global biodiversity loss is mainly due to human activities such as an intensification of forestry. Boreal forest ecosystems in Fennoscandia are characterized by disturbances such as forest fires, storms and floods. However, industrial forestry practices suppress forest fires and change the landscape, leading to a loss of habitats and associated species. Particularly lichen species with slow adaptation abilities and a strong substrate specificity face an extinction debt in boreal forests since their substrates are long-lived but no longer created. In this study the species-substrate relationship of two red-listed forest-fire dependent lichen species Carbon-icola anthracophila and C.

Död ved i vatten - funktionella strukturer och dess påverkan på öring (Salmo trutta, L.)

The background to this work was to see if there was a connection between large woody debris (LWD) and the presence of brown trout in our Swedish forest streams. Previous researches by Degerman et al. (2004) have shown that there is a strong correlation between the amount of dead wood and the presence of brown trout. The goal was then to find a way to restore, maintain and increase the trout habitats by constructing and adding manmade wooden structures that would mimic natural deadwood and its features in flowing water. The inspiration was partially taken from a water restoration program in the Klamath River of northern California, USA.

Alla vill beta men ingen vill bränna : skogshistoria inom Särna-Idre besparingsskog i nordvästra Dalarna

In this work I have tried to reconstruct the forest history within Särna-Idre forest common in northern Dalarna from the 19th century until present time. The Särna-Idre region has been an extensively used landscape for a long time. Pollen which indicates grazing has been found in samples orginating from the 10th century. Early travellers from the 18th and 19th centuries seem to have been passing trough a "used" landscape. Burned forests on naked ground are described as common. Also large areas are mentioned as undisturbed with lots of large trees, snags and dead wood.

Bokhögstubbar i Klåveröds strövområde : utbredning, egenskaper och betydelse för rödlistade vedlevande skalbaggar

Lack of dead wood is the main cause of decaying or loss of populations for many forest species. To increase the amount of dead wood is a prerequisite to maintain biodiversity in forests of northern Europe. In summer 2006 the recreation area Klåveröd, at Söderåsen in Skåne, Sweden, has been inventoried for high stumps (snags) of beech, (Fagus sylvatica). The result of the inventory has been compared with data of the real estate and forest management directories from the owner, region Skåne. The results have also been matched with the results from an inventory of saproxylic beetles in 2005, performed with windowtraps on selected snags both in the area and the adjacent national park Söderåsen. 594 snags were found on 747 ha.

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.

Naturhänsyn på certifierade privata skogsfastigheter : en jämförelse i praktiken mellan FSC och PEFC i Sydsverige

Nature conservation on certified small private forest owners- a comparison between the two certification systems FSC and PEFC in southern Sweden Today two different certification systems are used in Sweden to certify forest, FSC (Forest Stewardship Council) and PEFC (Pan European Forest Certification). During the last years certification of forests in general and different certification systems have frequently been debated. FSC is a globally widespread system and about 10 million ha out of 23 million ha Swedish forest is FSC-certified. The FSC-standard is mainly used by major forest companies and to some extent also by smaller private forest owners. PEFC is a European system and about 2 million ha Swedish forests is PEFC-certified today.

Val av stommaterial : Vilket är det mest fördelaktiga stommaterialet vid uppförande av en hallbyggnad?

When constructing an industrial- or hall building, the most common framework materials thatis used are wood, steel or concrete. Due to an assignment from Byggnadstekniska Byrån ABhas a document been created that makes it possible to investigate how the final costs is af-fected by gapes in between elements and which used foundation. And this with steel as thematerial. The purpose with this essay is to investigate which is the most well fitted materialwhen constructing an industrial- or hall building wood, steel or concrete. Information aboutthe different materials has been collected by litterateurs and by different internet pages.

Hur påverkar naturvårdsåtgärder mängden av vedlevande insekter : Manuellt dödade träd vs självdöda

Today?s forest managers implement a large number of methods to increase the amount of dead wood in Swedish forests. They use everything from high cutting of trees to girdling trees and burning forests. However, implementation of these measures without proper knowledge of their consequences is a common problem. This study has been performed to increase knowledge about two of these measures, girdling and high cutting, and how these actions affect the number of wood-living insects living on dead trees.

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.

Större svartbagge Upis ceramboides i norra Hälsingland : förekomst, substratkrav och effekter av skogsbrukets naturvårdsåtgärder

Many wood living insects are considered threatened by modern forestry due to the reduction in amount of dead wood. During the last decade various methods have been used to enhance the quantity of dead wood in managed forests. However little is known how and if these methods are aiding saproxylic insects. The threatened tenebrionid beetle, Upis ceramboides, is already extinct in southern Sweden. It develops in white rotted dead birch (Betula spp) and requires sun-exposed sites.

Land of the dead : Mer än bara zombies

Vår uppsats kommer beröra Zombies på film och fokusera på filmen Land of the Dead. Många människor upplever zombies som inget mer än monster, en fara för karaktärerna att klara sig undan. Vi vill uppmärksamma att all populärkultur i varierande utsträckning gestaltar verklighet, och analysera hur Zombies används för att gestalta aspekter av vårt samhälle..

Betydelse av lövinslag, död ved och variation i träddiameter för artrikedomen hos småfåglar

Forest management contributes to the changes in forest structure by turning heterogenous forests of varied age into homogenous forests of similar age and thus affect bird species depending on different structures or habitats which are lost during forestry. In this report, a study was made to investigate how the amount of decidious trees, dead wood and variation in tree diameter affect bird diversity. The purpose of this study was to be able to give forest management guidelines to increase bird diversity. This study was conducted by investigating 65 transects in forests of different structure south of Linköping, Sweden. Along the 65 transects, birds were inventoried as well as the vegetation.

Naturhänsynen i FSC-standarden : vetenskap eller gissningar?

The Swedish FSC standard (Forest Stewardship Council) is a level standard used to certify forestry. All the major Swedish forest companies are using the FSC standard, and approximately 50% of the Swedish forests are FSC certified today. In the essay six items within the chapter on environmental issues and biodiversity are examined: the proportion of protected forest, the proportion of annually burnt clear-cut stands, the number of trees with large diameter, the amount of dead wood, the proportion of deciduous trees within a stand and the proportion of deciduous-dominated stands. The FSC standard states a level for all items, and the purpose of the essay is to analyse whether these levels are supported by research within the field of conservation biology. The validity of the levels of the six items is them discussed to evaluate whether changes are required to the next revision of the FSC standard.

Brandrelaterade insekters lokala artrikedom i förhållande till olika miljövariabler : Fokus på betydelsen av konnektivitet på brandfält i boreal skog i Västerbottens län

The last century, forest fires have decreased in frequency due to efficient fire-suppression along with the growth of the industrial forestry. Since 1990, fire has been reintroduced under controlled forms to recreate burnt habitats. Many species that are dependent on, or benefits from, forest fires have increased since fire was reintroduced. The importance of connectivity is often addressed in ecological research. This is particularly important for species dependent on short-lived habitats such as burnt forests.

Effekt på värdeutfallet av sågad vara vid övergång från 30 till 60 cm moduler : - en fallstudie av Moelven

The purpose of this study is to explain how the value of sawn wood changes when sawn wood are cut in 30 respective 60 cm lengths. The raw material into the saw mill will mainly be bucked in 30cm and 60 cm modules. There will also be two alternatives where the timber will be bucked special lengths, 370, 490 and 550 cm but also in 490 and 550 cm.The method used for the study is to simulate both cutting and sawing the woods. For cutting the simulator Timan is used and for sawing the simulator Timberopt is used. When data is generatedfrom the simulators, calculations of some key figures is done and also how much the revenue need to be increased for the sawn wood in order to cover for the increased costs of changing sawn woodfrom 30 cm to 60 cm modulesThe conclusion is that the single biggest reason, impacting the value of the sawn wood is the cutting at the saw mill.When going from 30 to 60 cm modules, the impact will be that the customers to the saw mill must pay more to increase the revenue by at least 10% for the sawn wood in order to justifice the changein production.It is also possible to increase the value of the products further by bucking the timber in three lengths, 370, 490 and 550 cm, in order to get 12 % increase of the share of longer sawn wood (>= 480 cm)..

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