Sök:

Sökresultat:

513 Uppsatser om Deteriorated wood - Sida 9 av 35

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.

PEG-migration? MALDI-TOF-analys av beläggningar från fyra arkeologiska träföremål

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2012:29.

"Underhållsfria fönster" : I vilken utsträckning är dagens "underhållsfria" fönster underhållsfria och hur ser man

AbstractThe aim of this examination paper is to get an overview on the ?no-maintenance? windowsthat exist on the Swedish market, like plastic and aluminium windows.By way of introduction the reader gets knowledge in the background and problemformulatethat this subject has. This introduction explains why it has become so popular to changeyour windows into plastic- and aluminium windows and there is an existing scepticismagainst PVC and aluminium as construction material for windows.The main part of this report is constructed by segments of interviews where bothproducers of windows and stakeholders gets to answer questions about their viewing onno-maintenance windows from a material and construction point of view and where theproduction is headed to in the future. This is followed by an evaluation of a questionnaireon how pleased the house owners that changed their old windows to no-maintenancewindows are, followed by an inspection of windows made up from wood and an aluminiumclothing, windows made from only aluminium and PVC-based windows. It ends with atheory part about the materials PVC and metal based upon facts included in literature.By reading this report you can draw the conclusion that no window can be entirely nonmaintenancebut that the materials PVC and aluminium still are good substitutes for woodto lessen the maintenance..

Mortalitet av bok i Biskopstorp och Frodeparken naturreservat, Halland :

The aim with this study was to investigate mortality in older respectively younger beech stands (Fagus sylvatica), the different types of dead wood in the forest and the availability of coarse woody debris (CWD). The research was carried out in previously managed and seminatural stands in Biskopstorp and Frodeparken, located north of Halinstad in Halland,Sweden. Data were collected from 22 stands with at least 50 % beech and with a minimum age of 5 1 years, ranging in size from 0,67 to 19,9 ha. A transect was placed in each stand, in which the diaineter on both dead and living trees with a minimum diameter of 50 mm was recorded. On seven to 13 dead trees, depending on the size of each stand, decomposition stage, primary and secondary cause of death, amount of fungi and the type of the dead wood was noted.

Vad påverkar skogsägarnas naturhänsyn vid föryngringsavverkning i region Mellannorrland? :

The objective of this thesis was to investigate what influence nature conservation measures taken at regeneration felling. Factors analysed were the forest owners´ situation and their characters, and information activities from wood-suppliers and the Regional Forest Board (RFB). The inventory was performed with a posted questionnaire followed up by telephone to forest owners and a posted questionnaire to wood-buyers. The forest owners were grouped in three strata, depending on the quality results (D- polytax inventory) of the taken forest conservation measures, and for this investigation forest owners were sampled from the population in the tree groups. In total 73 % (41/56) of the sampled forest owners answered the questionnaire Group A (17 answers): Good judgement Group B (19 answers): Bad judgement Group C (5 answers): This group was formed from the forest owners that were informed, by RFB, about nature conservation measures and culture history consideration before the regeneration cutting.

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.

Datering av röta i hålekar :

I have chosen in this work to examine which factors are affecting the artificially creation of a tree cavity containing decomposed wood. The purpose of the work is to find out which factors are affecting the most when a tree cavity is created, and to apply these results when you artificially try to create a tree cavity. The need to create tree cavities comes from the situation where many tree cavity living beetles finds themselves today. When existing trees are to pass out there will be no suitable inheritors yet. The work was initially to focus on cavities created from cut branches.

En marknadsundersökning om regelvirke : kvaliteter och kunduppfattningar

Today there is a widespread opinion that the woodmarket and the forest industry are dominated by a traditional way of thinking and not adapted to the customers of today; a lot of products are produced purely on routine. Also, there is a demand for improving the quality of sawn woodproducts. AB Karl Hedin wants to sort this out by increasingly adapt their products to the demands of the market, i.e. through introducing a short wallstud of standard length, "Hedinregeln". At tirst, the wallstud will be produced in lengths of 2,70 m and of guaranteed quality.

FE safety analysis of a high speed wood planer cutter. An alternative method to achieve the requirements of EN847 standard

In the last decades, high speed cutting has become an attractive technology in the wood industry. The possibility of reducing global costs in addiction with an increase in productivity, were the main reasons for the enlargement of the use of this technology. As usual, these advantages are accompanied by disadvantages that should be carefully analyzed. If on the one hand cutting forces are reduced with increasing cutting speeds, on the other hand, the centrifugal forces affecting the tool are higher. Exposed to such high loads, there is a considerable risk of tool failure that embeds hazards for both machine and workers.

Fuktskador i ytterväggar på grund av vattenintrång

Moisture damage in buildings is a serious issue that leads to problematic consequences and high economic costs. Despite the knowledge and awareness existing about moisture problems, extensive damager still occurs today. Studies of moisture in the exterior wall constructions shows that the issue if often caused by rain and water intrusion. These kinds of problem result in major costs usually because the companies have to replace the material and structural components and also in some cases tear down large parts of the buildings.The work includes moisture theory and descriptions of four different exterior wall constructions, wood stud wall with plastered facade, exterior wall with wood facade, exterior wall with concrete, and exterior wall with brick facade. Our thesis work describes how the constructions are affected and moisture damage due to water intrusion.

Att utforska historisk slöjdkunskap genom klyvning och svepteknik. Ett exempel på forskning i hantverk

Uppsats för avläggande av filosofie masterexamen i kulturvård, 30 hp.

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.

Naturreservat : en bra naturvårdsåtgärd för att bevara enskilda arter och/eller bevara den biologiska mångfalden?

The examination of the adequate nature conservation methods in a natural reserve, to conserve a specific species and / or increase biological diversity is the subject of this study. This work is based on four species, that can be found during the Spring season, liverleaf, wood anemone, brimstone and woodpecker. The incidence and availability is studied and closely observed for these species in twenty forests, i.e. ten forests which are nature reserves and ten forests with the similar characteristics as the nature reserves habitat, but are not nature reserves in Gnesta mucipality, Södermanland. Measurements of the tree crown and the diameter of the tree trunks where noted to study how these factors could affect the outcome of the abundance and incidence of the four species.

Metodutveckling för analys av klorfenoler i jord samt analys av förorenad jord från ett sågverk

In this final thesis, an existing method for analysis of chlorophenols (CP) in bottom sediments has been updated and adjusted for analysis of chlorophenols in soil. The covalent bonds between the chlorophenols and the soil matrix were broken through basic hydrolysis and the chlorophenols were then separated from the water phase through addition of sulphuric acid followed by ether extraction. The chromatography was improved through extractive acetylation of the chlorophenols.The updated method was then applied on soil samples from a contaminated area (a former sawmill in Hyttsjö, Östergötland, Sweden).The analyse was preformed by GC/MS with respect to 2-MonoCP, 4-MonoCP, 2,4-DiCP, 2,6-DiCP, 2,4,6-TriCP, 2,3,4,6-TetraCP and pentachlorophenol (PCP).Contamination of chlorophenols in nature can be explained by the former use of wood preservative chemicals based on chlorophenols. In the 1960s and the 1970s these chemicals were used in Sweden, but due to their toxicity they were banned by the Swedish government in 1978.In Hyttsjö a pentachlorophenol-based product named Santobrite was used for several years. The concentration of PCP in the soil samples from Hyttsjö varied from 0.2->1.8 ng/mg dry substance.

Tillfällig partiell isolering av limfärgsbemålat trä vid behandling med fuktbaserade metoder - en jämförande studie av cyklododekan och mentol

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorsprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2013:12.

<- Föregående sida 9 Nästa sida ->