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697 Uppsatser om Wood density - Sida 4 av 47

En studie av utvecklingen av drivningsnettot i skogsbruket :

This master thesis consists of an investigation of the profitability per hectare in privatly owned forest land. The investigation is based on data collected from Skogsstyrelesen, Riksskogstaxeringen and Skogsforsk. During the last twenty years the prices on pulp wood and saw log have substantial decreased, but during the same time the the volumes from final felling have increased and the cost for felling has decreased, this investigation shows how the netprofit per hectARE after final felling has changed between year 1980-2005 This investigation shows that that the netprofit has stayed on a stable level during the years 1985-2005 even though prices pulp wood and saw log decreased. Much indicates that the demand of swedish pulp wood and saw log will continue to be strong or even stronger wich will give increased prices and an higher netprofit after final felling in the future.

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.

Bastu-frigidarium,energieffektivt system för återhämtning

Sweden is considered to have one of the world's highest animal welfare standards in agriculture. Despite this, there are shortcomings in animal husbandry. One example is overcrowding, which is a way to increase stock size without making costly investments in the buildings. It can be carried out systematically to increase profitability or due to, for example uneven calving during the year. The European Commission criticizes the fact that stocking density is not controlled under Swedish welfare inspections.

UTVÄRDERING AV ARBETSMETODER OCH KONTROLL AV BELÄGGNINGSGRAD BLAND MJÖLKKOR I LÖSDRIFT I HALLAND

Sweden is considered to have one of the world's highest animal welfare standards in agriculture. Despite this, there are shortcomings in animal husbandry. One example is overcrowding, which is a way to increase stock size without making costly investments in the buildings. It can be carried out systematically to increase profitability or due to, for example uneven calving during the year. The European Commission criticizes the fact that stocking density is not controlled under Swedish welfare inspections.

Hårdgörning av Asp

Hårdgörning av trä syftar till att göra materialet hårdare. Detta går att åstadkomma genom komprimering, det komprimerade materialet tenderar dock att återgå mot sin ursprungsform då materialet utsätts för fukt om ingen låsning sker. Låsningen kan ske mekaniskt i en treskiktskonstruktion som motverkar träets fuktrörelser. Dessa skivor har dock visat sig vara instabila och tidigare försök har uppvisat deformationer i form av kupning. Denna undersökning syftar till att utreda förutsättningarna för att använda komprimerad asp samt att ta fram underlag för framtagning av en kommersiell produkt.Praktiska tester har genomförts för att studera hårdhet, återfjädring och densitet hos det komprimerade virket.

Jämförelse mellan sådd och naturlig föryngring av tall i Härjedalen

The purpose of this study was to compare naturally regenerated Scots pine (Pinus sylvestris (L.)) against seeded Scots pine in terms of benefits and differences. An inventory was performed at a number of different sites, 4 ? 6 years after soil scarification and data on the number of new established plants, their height growth as well as ground-line diameter was collected. Information about site conditions such as altitude, quarter exposure and frost risk was also collected. A review of previous studies was conducted in addition to the field study.

Stöldskydd

To save energy it?s popular to build houses with low energy loss. In these houses the walls are keeping a lower temperature in the external side which leads to a higher relative humidity. In addition more material, such as wood studs, are used which means that there is more moisture to dry. More moisture in combination with higher relative humidity may pose a higher risk of microbial growth.

Cassava as an additive in biomass fuel pellet production :

In this study, the effects of using fine milled cassava stems as an additive in biofuel pellet production was compared to the effects of refined starch addition. The bulk biomass fuel raw material, to which the additive was added, was a blend of spruce and pine sawdust. An experimental design in the factors cassava/starch content, moisture content and material temperature was used. Measured responses were pellet bulk density, pellet durability, amount of fines, pelletizer motor current, pellet temperature, die temperature and CV for pelletizer motor current (a measure of process stability). Each response was modeled by multiple linear regression (MLR).

Epixylic lichens and bryophytes in young managed forests : substrate preferences and amounts of dead wood

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, .

Vad tycker skogsägare om virkesinköpare och inköpsorganisationer? : utveckling av ett skogsbolags tjänster och köpverksamhet till privata skogsägare

The private forest owners play a key role in the supply of round wood to the Swedish forest industry. Today it is a keen competition between forest companies about the wood from private forest owners. In order to get access to the wood from the private forestry you need to be an attractive collaboration partner, who can offer long-term collaboration, service at top-level, and acting for good prices to the forest owners. This work aims at analysing the situation on the market today. It gives Sveaskog purchase department a good view of the forest owners? opinion in general about the existing purchase activities. Forestry service level and timber prices are determining factors for a successful relationship between forest company and forest owner.

Inverkan av olika joner och jonconcentrationer på porstorleksfördelningen i trämassa-fibrer

The basic ingredient of paper is the individual wood fibers. The property of the fibers depends on a variety of factors e.g., method of pulp production and processing. The final sheet quality depends in part on how the fibers interface between each other and therefore factors that affect the fiber size are of interest.The flexibility of the fibers depends in part on the pore water i.e., the fiber swelling. The sheet becomes less flexible at low water content which gives a loss in strength. Thus it becomes desirable to increase the water uptake.The experimental investigation described in this report consists of exposing the wood fibers to different ions and ionic strength and then measure the pore size by thermoporosimetry where a DSC (Differential Scanning Calorimeter) is used.

Hur såg Birkas hamn ut och vilka transporter behövdes?

What is located on the bottom in the water outside of Birka? Remains of a water palisade or jetties and other constructions.Birka a Viking Age town that existed between AD 750 and 975 was located on the northwestern part of the small island of Björkö, in the Mälar archipelago of the Baltic Sea in Sweden. The Town was protected onshore by a hill fort and a town rampart. It is a widely spread assumption that Birka had a water palisade as a part of its defense. There are logs and other remnants on the bottom of the lake dating back to the Viking age.

Fältmätningar av limträbalkars elasticitetsmoduler : utvärdering av tre mätmetoder

This study investigates three different methods for evaluating MOE,Modulus of Elasticity, in field measurements. The purpose is toinvestigate the possibility to use dynamic measurement methods infield measurements that hitherto (2010) has been performed with staticmethods. The objects of investigation are 20 glulam beams. The firstfield measurement took place in november 2007 and applied a staticmethod based on the standard SS-EN 408. The second measurement,described in this study, took place during summer 2010, and appliedstatic as well as dynamic methods.The MOE of wood is affected by a range different factors.

Clear-cut and substrate characteristics important for the occurrence of the beetle Upis ceramboides

Disturbances, such as fire and wind, are important for saproxylic beetles (= beetles depending on decaying wood) to gain substrate in boreal forests. Clear-cutting is an example of a man-made disturbance. Measures such as prescribed burning have been made to resemble natural disturbances. The aim of this study was to see which clear-cut characteristics are important for the occurrence of the saproxylic beetle Upis ceramboides. This is a species favored by open habitats and is said to respond positively to forest fires. The distribution area in Sweden for this species has decreased during the last two centuries and I wanted to see if there were differences between clear-cuts in Hälsingland, where it is very rare and decreasing, and Norrbotten where this study was conducted.

Skogsbristen i Smålands bruksskogar : en studie av träkolsförbrukning vid Storebro Bruk 1793-1850

The forest in the county of Småland has been utilised for a long time. One of the most important forms of utilisation of wood has been charcoaling for the benefit of the iron industry. Shortage of forest in relation to the iron industry, was discussed already in the 17th century in Sweden. The aim of this study was to analyse the purchase and consumption of charcoal at Storebro Bruk, an ironwork in Småland, during the period 1793-1850, as well as analyse the shortage of forest at the time. To determine the utilisation of the forest in the area, I have used historical sources from Storebro Bruksarkiv.

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