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592 Uppsatser om Dead wood - Sida 13 av 40

Produktivitet vid stubblyftning :

Stump wood was used between 1850 and 1950 for production of tar and as firewood. In the 1950s the use decreased because of the introduction of the cheap fossil oil. In the 1970s stump wood became an interesting issue again as a raw material for the pulp industry. Stump lifting has today become a possible source for bioenergy. The objectives with this study were to investigate the productivity of stump lifting and stump extraction, and to analyse the economy.

Fire impact in the wood quality and a fertilization experiment in Eucalyptus plantations in Guangxi, southern China

Chinas government has a multifunctional program for a more sustainable forestry since 2000. This six key forest programs goal is to develop a more sustainable forest sector but also take environment consideration. The state forest administration in China has decided to create 5.8 million hectare of fast growing and high yield forest. Eucalyptus has showed to have good properties for pulp and timber production and therefore Eucalyptus plantations are under development in costal areas in southern China. By adding extra nutrients, growth can be enhanced in Eucalyptus plantations.

Fertilization in Eucalyptus urophylla plantations in Guangxi, southern China

StoraEnso decided in year 2002 to build a pulp mill in the province of Guangxi, southernChina, and also establish eucalyptus plantations to provide it with raw material. By 2010StoraEnso controls about 90 000 of planned 120 000 ha, out of 75 000 ha is already plantedwith Eucalyptus.By using better genetic material, improve the tending, selecting the sites more careful and byusing a proper fertilization regime StoraEnso hopes to increase the mean annual incrementfrom today?s 25 m3/ha, on bark, to 35 m3/ha. This study is one part in this work to increase themean annual increment in the plantation.This master thesis is the forth in a series, that has followed up a fertilization trial that startedin spring 2006 when the trial was laid out and treatments decided. The aim with the trial is toexamine the production potential of Eucalyptus urophylla in Guangxi, southern China.

Miljödifferentierad fastighetsskatt

It is essential to reuse- and recycles residues to decrease the amount of deposit materials and reach sustainable energy use. Two ways to work towards this is to recycle wood ashes to the forest as nutrient compensation and extract biogas from combustion of biomass.The aim with this study was to decide whether wood ashes that been used for biogas upgrading with accelerated carbonation also can be used as a nutrient compensation in the woods according to recommendations from the Swedish Forest Agency (Skogsstyrelsen).The ashes that were used in this study came from Johan Andersson who works at JTI in Uppsala, who also treated the ashes with biogas. The ashes have, in both untreated and treated condition, been analyzed in this study according to contents of elements, leaching properties, hardening properties and contents of crystalline phases, to evaluate what impact carbonation with biogas has on the ashes.The accelerated carbonation led to hardening of the ash, and decreased amount of CaO- and increased amount of CaCO3. The CO2-uptake also entails a dilution of the elements, and the content of nutrients and trace elements decreases. However the results show an indication of an uptake of S from the biogas to the ash, since the dilution had a smaller impact on S than the rest of the elements.

Markberedningens, planteringspunktens och behållardjupets inflytande på granminiplantors etablering i fält :

A new type of forest tree seedling, called mini seedling, has been developed by the University of Dalarna in Garpenberg, Sweden. Compared to traditional containerized seedlings that are grown for 1 ? 2 years, mini seedlings are grown for only 10 weeks. The mini seedlings are small, easily planted, cost effective, and reduce the amount of chemicals used in the nursery. Research has shown that mini seedlings tend to have higher overall survival rates than traditional container seedlings.

Tillväxtreaktion hos skärmträd i högskärm av gran i Medelpad :

Different methods for shelterwood cutting have been used in differ-ent parts of Europe since the middle ages. The use of shelter wood cutting in Norway spruce (Picea abies (L.) Karst.) forests in Sweden met a revival in the early 1990s as an alternative for the dominating clear-cutting system when silvicultural costs increased dramatically for the latter. Shelterwood cutting systems involve some possible problems but also a lot of positive effects. Among the problems are increased risk of wind throw and damage of the remaining shelter trees caused by the cutting operation. Positive effects are for example a valuable growth in the remaining trees and increased biological di-versity. This study is based on a total of 79 trees from 4 different treatments in a spruce shelterwood, cut in 1994, in the middle of Sweden (62,4º N).

Analys av interna transporter och buffertlager vid Vest-Wood Sverige AB

Denna rapport är resultatet av en analys som gjorts vid Vest-Woods fabrik i Forserum under våren 2007 i syfte att reducera interna transporter. Vest-Wood AB i Forserum tillverkar dörrar för den svenska marknaden men förser också en annan fabrik (SdrFelding i Danmark) i samma koncern med dörrstommar. Materialhantering för att förse Sdr Felding fabriken med dörrstommar medför i dagsläget mycket interna transporter i Forserumsfabriken. För att klara ojämn efterfrågan från Sdr Felding fabriken samt för att kunna jämna ut sin egen produktion har Forserumsfabriken valtatt lagerföra de tolv artiklar som beställs mest frekvent från Sdr Felding fabriken. Buffertlagret vid Forserumsfabriken där artiklarna lagerförs är placerat ca 200 m från produktionen vilket medför mycket intern transport för hantering av dessa.

GIS-modellering av habitat för vitryggig hackspett (Dendrocopos leucotos) som hjälpmedel i naturvårdsplanering på landskapsnivå :

The white-backed woodpecker is a forest bird being critically endangered in Sweden. The species is dependent on older forests rich in deciduous trees and Dead wood. The main problem for the survival of this species is present shortage of habitat. Conservation work on this umbrella species is at present focused on finding remaining or emerging habitat networks. Large areas are scrutinized in search for suitable habitats to be protected or managed for the species sake.

Ekologisk landskapsplan för fastigheten Götebo 1:5 :

This thesis constitutes a long term (100 year) ecological landscape management plan for the estate Götebo 1:5. The estate is situated close to Gothenburg and is owned by Skogssällskapet. The planning has been made by dividing the estate into different areas (zones). In each zone one of the goals nature conservation, recreation or economical yield has been prioritized. Nature conservation is one of the main goals for the forest management plan.

Utdragshållfasthet av inlimmade skruvar i limträ

In this thesis tests has been performed on the pull strength of screws glued into glulam beams.The experiment is based on the already approved method whereby the diameter of the drilled holes is the same as the screw outer diameter of 1 mm or bigger. The screws strength class shall not be less than 4.6 (EN ISO 898-1:1999, 1999).The difference in the experiments that were performed where that the drilled diameter were 1 mm smaller than the outer diameter of the screw so that the screw thread was worked into the wood.In the tests the gluing where made on M8 glulam beams. The screws where drilled at and angel of 90°tangental to the fiber direction with a diameter of 7 mm. The gluing of the screws where made in three different depths and where later exposed to pulling forces. The results showed both pulling breaks and screw breaks when they reached their maximum capacity.

Effekt av karbonatisering med biogas på aska från trädbränslen

It is essential to reuse- and recycles residues to decrease the amount of deposit materials and reach sustainable energy use. Two ways to work towards this is to recycle wood ashes to the forest as nutrient compensation and extract biogas from combustion of biomass.The aim with this study was to decide whether wood ashes that been used for biogas upgrading with accelerated carbonation also can be used as a nutrient compensation in the woods according to recommendations from the Swedish Forest Agency (Skogsstyrelsen).The ashes that were used in this study came from Johan Andersson who works at JTI in Uppsala, who also treated the ashes with biogas. The ashes have, in both untreated and treated condition, been analyzed in this study according to contents of elements, leaching properties, hardening properties and contents of crystalline phases, to evaluate what impact carbonation with biogas has on the ashes.The accelerated carbonation led to hardening of the ash, and decreased amount of CaO- and increased amount of CaCO3. The CO2-uptake also entails a dilution of the elements, and the content of nutrients and trace elements decreases. However the results show an indication of an uptake of S from the biogas to the ash, since the dilution had a smaller impact on S than the rest of the elements.

En husurna i Fälle : En diskussion om husurnans och rösens betydelse under Bronsåldern i nordöstra Smålands kustlandskap

In this essay I aim to examine how the landscape of Mönsterås might have looked like during the Bronze age in order to get a better understanding of the house urn that C J Ekerot found in a cairn in Fälle. Mönsterås is an area which has a quality of permanence, from Stone Age to Iron Age with its culmination during the Bronze Age. I will discuss the use and symbolic meaning of the house urn. The house as a symbol during the Bronze Age seemed to have had an important place in the cosmology. I will also discuss the importance of cairns, especially in the archipelago areas.

Förekomst & kostnad av kapsprickor i stormaskadad skog

The aim for this study where to investigate the frequency of cutting cracks in saw timber harvested in the storm-damaged forests in regions where the storms Hilde and Ivar hit. The idea for this work came from one of the region?s biggest actors, SCA Skog and Jämtlands district. The purpose where to find out how big proportion of the saw timber that contains cutting cracks, their financial cost in lost wood value and also give advice and suggestions on how to work against the frequency of cutting cracks. For the field-study some guidelines where used to make sure that the samples were taken under the same conditions, they were: ? The field-study must be performed under harvesting of storm-felled forest, which are horizontal/inclined trunks. ? The averaged sized tree will make it possible to harvest saw timber. ? The trunks can?t be root cut. A methodology called in Swedish ?Trissmetoden? was used because it is the most frequent used methodology in earlier performed studies and the only one that can be used I field. Under the field-study data were collected from 570 saw timber logs, 30 logs from each one of the tested harvesters.

Två nya trailerkoncept för transport av rundvirke hos Stora Enso : en analys av prestation och flexibilitet

The need for roundwood transport capacity vary throughout the year. The need during a period is influenced mainly by the volume transported the period, the number of days during which transport can be carried out, seasonal variations in road conditions and the weight of the roundwood, and the origin of the wood (private forest owners/ forest companies). The need for transport capacity generally increase during the winter and in spring, after thawing. Lack of logging trucks combined with a lack of drivers for these trucks make it hard to hire extra help during periods of increased transport capacity needs. It is also very expensive to keep logging trucks for use only during these periods. In this thesis, two new concepts based on the partial transport by truck tractors have been examined, to find out the possibility for increased performance and flexibility.

Generell hänsyn vid avverkning : påverkan av dispens från sexveckorsregeln samt skogsägares kunskap, tankar och åsikter

The forests in Sweden have, for a long time, been managed intensively. This has led to even-aged stands with few tree species and a lack of Dead wood. Therefore, general conservation measures in connection with regeneration felling are important in order to promote biodiversity. Inventories carried out by the Swedish Forest Agency, however, show that about 25 % of the felled area does not reach the level of the Forestry Act, regarding general conservation measures. The aim of my study was to see whether exemptions from the six week notice of reporting regeneration fellings (the Forest Agency demands a report six weeks in advance of fellings), affect the results of the general conservation measures taken.

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