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125 Uppsatser om Stem - Sida 3 av 9

Stem injection of different nitrogen forms into young Norway spruce

This master thesis has been a pilot study preceding a forthcoming project of a larger scale with the long term objective to separate the direct effect of added nitrogen on soil processes from indirect effects via trees. The aim of this study has been to investigate the allocation of nitrogen following direct injection of liquid solutions into the xylem of 40 year old Norway spruce. The field site is located at Flakaliden (64°07?N, 19°27?E), approximately 60 km northwest of Umeå, Sweden. A total of 18 trees were selected for treatment, equally divided between three treatments, potassium nitrate, glutamine and water (control).

Multipel Skleros En kartläggning av infektionskomplikationer i samband med hematopoetisk stamcellstransplantation

ABSTRACTMultiple sclerosis (MS) is the leading cause of adult disability inSweden. Hematopoietic Stem cell transplantation (HSCT) can be used as a treatment option for patients with MS where the disease has an aggressive course. The treatment is preceded by high-dose chemotherapy which lowers the patient's immune syStem. It is therefore of interest to study infectious complications associated with HSCT in this patient.Aim: The purpose of this study was to identify infection problems in this population associated with HSCT, and to study differences in infectious complications between this group and patients diagnosed with lymphoma who have undergone the same treatment.Method: The study was a retrospective descriptive study with quantitative data. A medical record review was conducted.

Användning av satellitdata för lokalisering av skogsområden där lövröjning bedöms angelägen : en analys av användbarheten med fjärranalys som hjälpmedel till röjningsrådgivning

This master thesis project is a part of a project called ?Järboprojektet? at the regional board of forestry, the district of Gästrikland. The project will give answers to questions regarding if an analysis of satellite images can be used to contact and inform landowners of the located areas where precommercial thinning is useful. The whole project is a part of the National Board of Forestrys IT-stake where the analysis of satellite images will, at the latitudes possible, be adapted to each district in purpose to identify these areas in need of precommercial thinning. This master thesis project is based on a field inventory of identified objects where precommercial thinning is useful.

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.

Volymsrapportering vid terrängtransport av virke

This report is a B.Sc. Forestry thesis work at the school for Forest Management, SLU. The work was an assignment from the forest owners? association Mellanskog. The aim of the work where to investigate the economical result of removing undergrowth trees before first thinning, and a follow-up of the contractors and their compliance with Mellanskog standards. This thesis work was divided in three parts: The first was to find a relation between the net volume from the first thinning and the cost of cleaning undergrowth trees. Secondly there was a follow-up in the field, to investigate whether the contractors have done the undergrowth cleaning according to Mellanskog?s directives.

Glowtest Fixture

The project, Glowtest Fixture, has been carried out to and in collaboration with MSA SordinLtd. MSA Sordin Ltd produces and sells ear protector and is at present a supplier on theworld market. Glowtest Fixture is a product for glow testing off detailed components in oneear protector. MSA Sordin Ltd sends today away your products for testing what is anexpensive aspect in their development. The project's aim is to take forward a test equipmentthat copes with those high nonplussed requirements and wishes that are required for anapproved physical execution.Glowtest Fixture is a physical equipment that comes used Stem glow physical off all detailedcomponents in one ear protector.

Fågelbär (Prunus avium L.) - överlevnad, höjdutveckling och skador i unga planteringar på småländska höglandet :

Plant survival, plant damage and height growth were studied in nine wild cherry (Prunus avium L.) plantations in southern Sweden established between 2000 and 2002. All stands were located to the county of Småland. The survey was conducted during May and June in 2007. During the survey the height, diameter and quality of the cherry trees were recorded. In one stand, red ? berried Elder (Sambucus racemosa L.) was a dominant species.

Förröjning i förstagalling - vad kostar det och följer utförarna instruktionerna?

This report is a B.Sc. Forestry thesis work at the school for Forest Management, SLU. The work was an assignment from the forest owners? association Mellanskog. The aim of the work where to investigate the economical result of removing undergrowth trees before first thinning, and a follow-up of the contractors and their compliance with Mellanskog standards. This thesis work was divided in three parts: The first was to find a relation between the net volume from the first thinning and the cost of cleaning undergrowth trees. Secondly there was a follow-up in the field, to investigate whether the contractors have done the undergrowth cleaning according to Mellanskog?s directives.

Att bygga en stamdatabas för gotländsk tall

Today's Swedish large-scale forestry uses almost exclusively computer-aided bucking. It allows the harvester computer, using an optimisation price list (steering price list), to maximize the value of each tree. The optimisation price list can be adjusted so that the industry gets the raw material it demands from the forest. There are various simulation programs that can be used when constructing a optimisation price list. The simulation program merchandise a database of Stem shapes using a given price list and mimics a harvester's work. To get the demanded raw material for the industry it is important to use a well-adjusted optimisation price list.

Stamskador i gallringsbestånd

This study was conducted on a property with a thinning machine team. The purpose was to investigate in which machine, the harvester or the forwarder, that caused most damage to the trees in six different stands. Different factors, related to the damage frequency in the stands, were checked out. For example: basal area per hectare, thinning strength, tree diameter and the rate of production. The harvester drivers were also interviewed about how, when and why Stem damages occur and how to minimize them. The study stated that 4.3 percent of the trees were damaged. Out of these 88 percent was caused by the harvester and the rest, 12 percent, by the forwarder..

Resultat från tre klonförsök med fågelbär, Prunus avium L, i södra Sverige :

This study was based on measurements of growth and shape of 50 clones of wild cherry, Prunus avium L, in south Sweden and aimed at finding out wether or not any of these clones are useful for commercial propagation. Initially, a short assembly of documented knowledge concerning wild cherry as a timber producing tree species was put together. The study of the 50 clones includes information gathered during the fall of 2006 from four trials located in the counties of Blekinge, Småland and Västergöland. The oldest trial, founded in Tranemåla, Blekinge, in 1992, was focused on offspring and aimed at discerning differences between provenances and at developing an adapted plant material. The other experiments were both clone trials and founded in 2002. These are based on 50 individuals selected from the offspring trial in Tranemåla.

Site preparation, planting position and planting stock effects on long-term survival, growth and stem form properties of Pinus contorta on southern Iceland

In order to evaluate different afforestation methods for exposed heath lands a field experiment was established in Mosfell on southern Iceland in 1989. The trial comprised six different site preparation methods (control, herbicide application, tree shelters, patch scarification, TTS trenching and mounding). In total 960 container seedlings (1+0) and 960 Nisula roll transplants (2+1) of lodgepole pine were planted. Various planting positions (furrow, hinge, no site preparation (control) and on top of mounds) were tested within the site preparation treatments. This study involves renewed measurements and analyses of the trial.After 19 years the overall survival was 51,7 %.

Höggallring i praktiskt skogsbruk : beskrivning av en gallringsmodell för granskog som tillämpas på Trolleholms Gods

When Norway spruce is planted with large initial spacing and grows on highly productive sites in southern Sweden, a high proportion of the Stems gets broad annual rings. The thinning programme carried out at the estate of Trolleholm aims to extract Stems with too broad ring width. The 3-4 first thinnings are carried out as thinning from above, where only the thickest trees are removed. The internal distance may not fall below 5-7 meters depending on the number of thinning (short distance in young stands). The aim of this study was to examine the thinning model that is carried out at the estate of Trolleholm. A volume table is calculated to describe the model, and data is collected on temporary plots.

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.

Utvärdering av produktionsrapporterad volym för contorta

The background to this study is that the forest company, Holmen, has found large discrepancies between harvested volume and the measured volume at the industry. Factors like bark features, breakage, double tops, bends and Stem damages was noted, and all Stems were measured manually. Hypothesis testing with the method "random in pairs" were used to examine whether the harvester measured values significantly differed from the manually measured. The result of a properly calibrated harvester shows in average underestimation of the volume with Skogforsk Pine as a bark function. This means that the harvester isn´t the reason why the volume measured in the industry is lower, the fault is elsewhere. The study also indicates a need for a unique bark function for logepole pine..

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