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841 Uppsatser om Multi-tree harvesting - Sida 8 av 57

Produktivitet vid stubbskörd :

Stump harvest could be found in the late 1970?s and the early 1980?s. And now when the prices on energy are high it has become an interesting topic again. This work has been conducted within Holmen Skog?s stump harvest testing in Norrköping.

Volume and taper equations for Sitka spruce (Picea sitchensis (Bong.) Carr.), Norway spruce (Picea abies (L.) Karst.) and White spruce (Picea glauca (Moench) Voss) in Iceland

The aim of this study was to evaluate different types of volume and taper equations that can be used to predict single-tree stem volume and stem diameter at any given height along the tree stem for plantation grown Sitka spruce (Picea sitchensis (Bong.) Carr.), Norway spruce (Picea abies (L.) Karst) and White spruce (Picea glauca (Mounch) Voss) in Iceland. A number of published tree volume equations were tested and modified to predict the total stem volumes over bark but three logarithmic equations were taken for more in-depth analysis. Three taper equations were tested. Two variable-exponent equations (Kozak 1997, Kozak 2004) and one exponential equation described by Biging (1984). Data from a total of 617 sample trees were used in this study, collected from stands in various parts of the country and present different types of stands growing in different soil types and cover most of the site conditions suitable for forestry in Iceland.

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.

Potentiella arealer för ökad virkesproduktion i norra Sverige genom skogsodling med Pinus contorta var. latifolia, Larix sukaczewii, Abies lasiocarpa, Populus × wettsteinii och Picea mariana

Sweden is a country with few native tree species. According to Govt. 2007/08: 108, exotic tree species may be seen as an opportunity to increase the growth of tree volume in Sweden. Potential areas where explored In this work for cultivation with Pinus contorta var. latifolia Engelm., Larix sukaczewii Dylis, Abies lasiocarpa (Hook.) Nutt., Populus × wettsteinii Hämet-Ahti (tremula x tremuloides) and Picea mariana (Mill.) Britton et.al.

Svansbitning hos grisar, arv eller miljö?

Tail-biting in pigs is an animal welfare issue and in Sweden during 2002 the producers lost tree million Swedish crowns because of tail biting. This economic loss depends on the pigs which are discarded at slaughter because of tail biting. Tail biting can be separated into two stages, "pre-injury" and "injury". The aim of this study is to investigate if tail biting depends on environment or genetic background.A lot of research on the environments effects on the behaviour of pigs but not so much on the genetic effects has been performed. The frequency of tail biting in pig farms influence among others of environment enrichment, ventilation, gender and breed of the pig.

Lämpliga främmande trädslag för Kalmar och Mönsterås kommuner

This report concerns the for Sweden foreign tree species hybrid larch, hybrid aspen and poplar, and focuses on the area Kalmar and Mönsterås municipalities. The report shows that there are not only advantages with these species. The larch, the most common of the alien tree species has the greatest problems due to that its timber is difficult to sell in the area but also the Larch´s poor pulp quality and is more likely to be damaged by wildlife than the spruce is. Hybrid Aspen is much easier to sell and is used like regular aspen for match wood and textile pulp. Its disadvantage is the high cost for plants and to prevent damage from wildlife.

Utbyte av massaved och biobränsle i några typbestånd av Contorta :

The aim of this study is to describe a number of type stands of lodge pole pine in Norrbotten with respect on stem volume and total biomass. Further questions to answer is if there is stand characteristics that make the stands more suitable for pulpwood in early thinning, or if it is better to apply whole tree harvest. The study shall also give an indication if bio energy can be an economical interesting alternative for Sveaskog. Sampled trees represented the variation in the different stands. Five trees were selected from each stand to represent that stand. Stem volume and biomass (kg dry weight (DW) per hectare) for each fraction was calculated.

"Jag har lite mer av allt liksom" : en salutogen studie av unga kvinnors erfarenhet av olika kulturella bakgrunder

Young women with immigrant background are generally looked upon as victims of patriarchal structures and cultural determinism.The purpose of this bachelor thesis was therefore to have a salutogen perspective. We investigated how young women with a transcultural background are affected by and how they use their experiences from different backgrounds in their creating of identity.We based our essay on qualitative interviews and current research on the subjects of multi culture, identity and youth. The interviewees were seven young women with experience of multi cultural background and performing different kind of artistic activity.The theory and empirical material combined and compared resulted in three themes: affinity, cultural hybridization, and salutogen factors.We saw that for those young women affinity functioned as a basis for creating identity and that their double background enriches them in several aspects. The three major salutogen factors that the interviewees had in common, and we emphasize, are their struggle, open mind and awareness of freedom.The global youth culture has a great impact upon the young women and to some extent we could recognize cultural hybridization. We consider this neglected subject urgent and very relevant for social work in the multi cultural society of Sweden..

Planteringsförbandets inverkan på bestånd av contortatall (Pinus contorta var. latifolia) med avseende på volymtillväxt och virkesegenskaper

At the beginning of the 1970´s forestry feared an imbalance in the future wood supply. Because of this anticipated "timber slump" forest companies undertook a variety of measures to counter this. One of these measures was the introduction of exotic tree species. The choice finally ended up with lodgepole pines which were considered a fast growing tree species compared to our native tree species. Theambition for the new lodgepole pine stands were to run these with rotation periods of between 40-60 years, thus smoothing out the ?timber slump? that was anticipated.

Rum och rörelse - analys av alléns betydelse för människa och landskap

Within literature, politics and science, there is a claim that ?tree avenues are important?. But the question and the goal for this essay are to explore the pretext to how and why. Planting tree avenues is a 4000 year old tradition and they are a common element in the Swedish and Scanian landscape since the 18th century. They were first mainly planted by aristocratic land-owners or on their initiative, but since the 19th century also by farmers.

Flerkanalspublicering : En kvalitativ undersökning av NTs arbete med att publicera nyheter i flera kanaler.

Title: Multi channel publishing: a qualitative study on how Norrköpings Tidningen publishes news in multiple channelsAuthor: Roland AlbinssonThesis supervisor: Per-Anders ForstorpBackground: In this day and age, the media is omnipresent and a part of our daily life. The phenomenon of media convergence can be traced back to the birth of the internet, and today all of the major newspapers have a website of their own. As a result of multichannel publishing, consumers have a wide range of tv channels to choose from, but there is still uncertainty as to whether more channels automatically equates to more and better news. There is no doubt about the fact that multi channel publishing is a necessary survival skill for media conglomerates today, but effects such as news recycling and the concentration of ownership are in conflict with the consumers? availability demands.Purpose: The purpose of this thesis is to, by means of a case study, describe how NT?s multi channel publishing is an expression of media convergence, as well as to study how the news are affected by multi channel publishing.Research procedure: This study is based on three different research methods, observations, text analyses and qualitative interviews.

Anläggningsmaterial för landskapsarkitekten ur miljösynpunkt

Tail-biting in pigs is an animal welfare issue and in Sweden during 2002 the producers lost tree million Swedish crowns because of tail biting. This economic loss depends on the pigs which are discarded at slaughter because of tail biting. Tail biting can be separated into two stages, "pre-injury" and "injury". The aim of this study is to investigate if tail biting depends on environment or genetic background.A lot of research on the environments effects on the behaviour of pigs but not so much on the genetic effects has been performed. The frequency of tail biting in pig farms influence among others of environment enrichment, ventilation, gender and breed of the pig.

Nationellt uppdrag och internationellt samarbete ? Nationalbibliotekens bevarandemetadata för digitalt skapat material

The National Libraries task to save and preserve the national cultural heritage has turned to a new challenge in a digital world. The preservation of born-digital material for future use requires not only saving the digital object itself but also information about the object, preservation metadata. This is a relatively new issue and the library community has very little experience in this area. It has become evident that international cooperation is necessary to solve the task and that the development of international standards is of fundamental significance. This thesis investigates what has been done to meet the problems with the fast obsolescence of digital material with the focus on metadata.

Prestationspåverkan av flerträdshantering i klena gallringar

The aim of this study is to investigate how multiple tree handling harvesters perform compared to earlier developed standards. The study shows that multiple tree handling harvesters are more efficient in thinnings stands with mean stock volumes less than 0,12 m3fub per stock. The increased efficiency is different for different mean stem classes. In stands with a mean stem volume of 0,04 m3fub per stock, the increase can be as high as 40 percent while it is about 10 percent in stands with a mean stem volume of 0,12 m3fub. Comparisons have been done between stands that are felled with partly limbed stands and stands without partly limbed assortments. The difference in performance is clear and shows that the partly limbed assortments strengthen the multiple tree handling harvesters positive effects in low dimension thinnings.

Ulla Molin - Östbergs trädgård i Lund

Tail-biting in pigs is an animal welfare issue and in Sweden during 2002 the producers lost tree million Swedish crowns because of tail biting. This economic loss depends on the pigs which are discarded at slaughter because of tail biting. Tail biting can be separated into two stages, "pre-injury" and "injury". The aim of this study is to investigate if tail biting depends on environment or genetic background.A lot of research on the environments effects on the behaviour of pigs but not so much on the genetic effects has been performed. The frequency of tail biting in pig farms influence among others of environment enrichment, ventilation, gender and breed of the pig.

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