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  • 1.
    Aaby, Susanne
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. 1991.
    Carlsson, Henric
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Effektivisering av timmerplan på Kinnaredsågen2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sågverken i Sverige letar kontinuerligt efter lösningar för att kunna effektivisera produktionen. I denna studie analyseras specifikt Derome Kinnareds sågens timmerplan. Genom en stopptidsanalys, undersökningar av nya tekniska lösningar, muntliga kommunikationer med personal samt arbetsledare och andra företag införskaffades underlag till analys. Åtgärder som kan utföras för att minimera produktionskostnaderna eller öka produktionen på timmerplan är att implementera ny teknik t.ex. fjärrmätning, digitalisera mätbesked med hjälp av SDC:s arkiv, omorganisera personalstyrkan samt införskaffa bemyndigad mätare. Förslagen indikerar att implementering av dem kan förbättra Kinnaredsågens ekonomi. Beroende på hur mycket företaget är villigt att investera kan det effektiviseras i olika grad. I samband med kommunikation med företagsrepresentanter kom man dock fram till att ny teknik kan vara bättre att implementera vid en nybyggnation.

  • 2.
    Abrahamsson, Håkan
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Skogstillståndet på ön Blå Jungfrun2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of the study was to investigate the forest in the national park on the Blue Maiden Island and compare with mainland forest data. The study was made in a quantitative way. The results from the field measurement were related to data from the Swedish National Forest Inventory.

    Oak, Scots pine and Lime were the most common tree species and constituted 47, 18 and 16 % of basal area, respectively, on the island.

    The mean heigt was 7 m and the volume of living trees was on average 72 m³/ha and dead wood 30 m³/ha. The average age at breast height was 137 years and the oldest tree was an oak with the age of 335 years at breast height. The amount of dead wood constituted 40 % of the total volume. Disturbances have had influence on the forest on the Island. To what extent cannot be determined without further investigations.

  • 3.
    Adamopoulos, Stergios
    Technological Educational Institute of Larissa, Greece.
    Νέες τεχνολογίες συγκοµιδής δασικών προϊόντων: [New technologies for harvesting forest products]2012In: "Harvesting, Supply and Trade of Woody Biomass". Centre for Renewable Energy Sources and Saving (CRES) and Department of Forestry and Management of Natural Environment, TEI of Larissa, 19 October 2012, Karditsa, Greece, 2012Conference paper (Other academic)
  • 4.
    Albaugh, Timothy J
    et al.
    North Carolina State University, USA.
    Bergh, Johan
    Swedish University of Agricultural Sciences.
    Lundmark, Tomas
    Swedish University of Agricultural Sciences.
    Nilsson, Urban
    Stape, José Luiz
    North Carolina State University, USA.
    Allen, H Lee
    North Carolina State University, USA.
    Linder, Sune
    Swedish University of Agricultural Sciences.
    Do biological expansion factors adequately estimate stand-scale aboveground component biomass for Norway spruce?2009In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 258, no 12, p. 2628-2637Article in journal (Refereed)
    Abstract [en]

    We developed site specific component (stem, branch, and foliage) biomass functions for two sites in Sweden (64° and 57° North latitude) where four treatments (control, irrigated, fertilized, irrigated plus fertilized) were applied in the existing Norway spruce stands (Picea abies L. Karst.) for 17 years. We tested for site effects in the component biomass equations and compared site specific biomass estimates to those generated using published functions ( Lehtonen et al., 2004 and Wirth et al., 2004). Site effects were significant for all components and indicated it would be unlikely to generate equations that well estimate biomass across the Norway spruce range as implicitly indicated in our efforts to generate species biomass expansion factors. We rejected our hypothesis that the published functions would well estimate component biomass for control plots. The published functions did not compare well with site specific component biomass estimates for the other treatments; both published functions well estimated stem mass up to stem mass of 25 Mg ha−1, beyond which stem mass was overestimated, and both functions over and under estimated foliage and branch mass. Nor did the published functions compare well with each other, with stem, foliage and branch mass estimate differences of 12, 55, −8% and 11, 77, and 59% for the southern and northern sites, respectively, when averaged over all treatments and years. Adding limiting resources through fertilization increased stem, foliage and branch mass 57, 11, 18% and 120, 37, and 69% at the southern and northern sites, respectively, which would increase carbon sequestration and available stemwood and bioenergy materials. We recommend that more effort is spent in process-based modeling to better predict mass at a given site and ultimately provide better estimates of carbon sequestration and bioenergy material production changes.

  • 5.
    Alvskog, Kristina
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Rotstock av tall: Hur blir den framtida virkeskvaliteten?2014Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    In Sweden the quality of Scots pine (Pinus sylvestris) saw timber has decreased. It is especially due to increased labour cost that has led to rational and effective forest management.

    This study investigated the quality of Scots pine and the potential to produce high quality stems in 9 stands in Bergslagen, Sweden. Two different stand types were investigated: Pruned stands and conventional managed stands. The outcome was a high percentage of valuable stems in the pruned stands (72-94 %), and 46-56 % in the conventional managed stands. It is possible to produce high quality timber of Scots pine with active management, for example by pruning and careful selection of stems in thinnings.

  • 6.
    Andersson, Anton
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Davidsson, Adrian
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Hur mycket står risskotare stilla på grund av kommunikationsproblem?2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The communicative interaction between contractor and subcontractor of residue forwarder plays a crucial role in the efficiency of handling forest residue. Since that type of work is at the end of the harvesting process, it may be that it is not as prioritized as the previous harvesting measures. The study investigates the communicative interaction between subcontractor that drives a residue forwarder and contractor and its connection to work-related production stops. The study was accomplished by a web-based survey and quantitative interviews conducted with eight selectively selected residue forwarder drivers in southern Sweden. The result of the survey showed that the average of all total production stops was one hour and 52 minutes under an average stop period of 25 working days. Most of the stops were caused by other work-related problems. Communication problems accounted for 20% of the number of production stops and the average stop duration was one hour and five minutes. The time when a residue forwarder was inactive seventeen minutes per day. In conclusion, the communicative problems are not the main reason to inactivity for residue forwarders. However, communication plays an important role in productive harvesting and represent the biggest possibility for improvement in the communication between residue forwarder drivers and contractor, which could lead to fewer production stops.  

     

    Residue Forwarders, Communication Problems, Production Stop and Forest residue. 

  • 7.
    Andersson, Björn
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Utvärdering och utveckling av Fiskarhedens Trävaru AB:s traktdirektiv för slutavverkning2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Gross felling has accelerated in recent decades, and as a consequence, the requirements for forestry have increased. Today a comprehensive environmental consideration needs to be taken. This also imposes higher demands on the contractors. In order for contractors to be able to live up to the requirements, it is important that the customer of the service hands over a work instruction in connection to the removal of region assignments. This work instruction and work order is created in the form of a region directive. A qualitative region directive is considered important for Fiskarhedens Trävaru AB and for their contractors. A case study has been conducted to evaluate and describe the company's current region directive. The results show that the current region directive is sometimes inadequate due to that they are poorly completed. Important content is therefore not communicated as needed. A proposal of a new improved region directive, where the content is intended to be filled in better, has therefore been developed. With the help of this region directive, Fiskarheden can maintain sustainable forestry.

  • 8.
    Andersson, Erik
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Noggrannhet och precision vid beståndsuppskattning av mobilapplikationen KATAM2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this essay was to evaluate the mobile application KATAM of accuracy, time, precision and practical use in comparison to volume estimation with data Digital Caliper and harvester report. The result of the diameter comparison showed similar estimates from KATAM and the Digital Caliper respectively. KATAM had a higher mean basel area, 7% and coarser mean diameter, 3.7%, compared to the Digital Caliper. KATAM also had overestimations in volume as compared to the harvesting report and the Digital Caliper concerning the mean stem, from 2.5% to 17.6%, depending on which sample areas were included and which version of KATAM was used. However, the basis of volume estimates was small and had error sources, which made the results of the measurements uncertain. Although the study shows an overestimation of the diameter, the mutual precision indicates that KATAM could be an alternative to the Digital Caliper when estimating the mean diameter.

  • 9.
    Andersson, Haidi
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology. 1965.
    Hur upplevs estetik i skogsbruket?: How is aesthetics in forestry perceived?2016Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
  • 10.
    Andersson, Ida
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Distansskogsägares nöjdhet med Södras tjänsteutbud och kvalité på tjänster2015Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    The development of technology and the mechanization in the Swedish forestry has during the last 60 years resulted in depopulation of the country side and due to that the amount of distance forest owners has increased. Therefore the forest companies need to make some adjustments in order to keep the distance forest owners as customers and to attract new ones. The purpose of this essay was to examine and analyze the distance forest owners satisfaction with Södras service offering and quality of service and further develop some proposals for action. A web-based survey was sent out to 634 distance forests owners in Stockholm, Sweden, all members of Södra. 269 respondents participated in the survey and of them, 27 did also participate in a follow-up telephone interview. The results show that the members generally was satisfied with the service offering and the quality of service. Suggestions for improvement regarding the service offering is all about implementing forest management courses in Stockholm and including providing financial and generational counseling, also on location in Stockholm. The quality of service can be improved if the inspector changes the way of working towards an even more customer adapted way and also improve the dialogue with the entrepreneurs. Further suggestions for improvement is to a greater extent welcome complaints and to give some compensation and/or apologize when it is motivated.

  • 11.
    Andersson, Jonas
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Föryngring med tallsådd- ett underskattat alternativ?2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this study was to investigate the attitudes of forest owners to direct sowing of pine (Pinus sylvestris L.) and also why so few have used the method. The study also aimed to identify reasons for forest owners to use or not to use the method. A questionnaire was sent to 240 non-industrial private forest owners (NIPFs) all over Sweden. As a complement, interviews were performed with forest companies from the north and middle parts of Sweden. The results showed that 15 % of the NIPFs respond that they had used the method direct sowing of pine at some occasion in the past. No forest owner origination from Götaland had used the method though. It was more common among those who owned a forest property of 100 hectares or more than among those who owned 49 hectares or less. Most of those who had used direct sowing in the past were satisfied with the outcome of the regeneration, 92 %, and 73 % were willing to use the method again. They also showed a more positive attitude to direct sowing, 86 %, compared to those who had not tried the method, where 23 % were positive and 69 % were neither positive nor negative. The main reason for not have used the method showed to be that the NIPFs answering this questionnaire had not thought about it. Of the companies interviewed in this study, Sveaskog and Holmen were the ones that have used direct sowing the most: Sveaskog sow 27 % of the yearly pine regeneration area and Holmen just over 20 % of the yearly pine regeneration area, including lodge pole pine (Pinus contorta Douglas ex Loudon). The main reason to why the companies have used direct sowing was that they consider the method cost effective. The also appreciate that the method results in a lot of stems per hectare which has been positive in areas where browsing is a problem. The results from the questionnaire showed that those had sown pine in the past tended to have a more positive attitude to the method than the forest owner that had not sown. This indicates that they have had a positive experience of the method. Nearly half of those who had not sown had neither a positive nor a negative attitude to it. One possible reason for it is that they had no experience of the method and therefore no opinion. Direct sowing works well to combine with other methods and can be adapted to different conditions. In a time when damage from browsing can cause big problems to regenerations of pine, sowing could be an important tool in the toolbox.

  • 12.
    Andersson, Matilda
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Naturkultur för bättre kvalitet i rotstocken i tallungskog?: Utvärdering av röjningsförsök i Kråkerödjan2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Scots pine (Pinus sylvestris L.) form a large part of Swedish forestry and has many alternative end-use areas with different requirements for quality. The ability to influence the quality is high in the initial planting and juvenile forest phase, as studies have shown relationships between good quality and dense planting, where competition between trees has a good impact on timber quality. Competition can also be achieved by shading from above, through seed trees or multi-layered forest. Interest in continuous cover forestry grows, and investigating differences in future timber quality between layered and clear cutting treatments can therefore be valuable. Such a method is “Naturkultur”, which aims to optimize the net present value at every point in the forest. The purpose of this study is to highlight the question of whether layered forests methods similar to “Naturkultur” can be used for higher timber quality in pine forests in a cleaning trial in southern Östergötland, Sweden. The goal is to find out if any difference in timber quality exists in the future butt log between the different cleaning treatments, layered (Uneven) and conventional (Even). The survey was limited to studying only the Kråkerödjan pre-commercial thinning trial, located on the property Kråkerödjan between Småland and Östergötland. Parameters for quality estimation were delimited to knot quantity and knot thickness. In order to answer the purpose, a field survey was conducted with quantitative assumptions where data about stem quantity, tree species distribution, height, diameter, height of the living crown, number of knots and diameter for the thickest knot from the base of the trunk up to 2 m on the trunk were collected. The result showed that the number of stems per ha was significantly higher in Uneven than in Even while the volume was next to the same. The average diameter was about 4 cm in Uneven and about 10 cm in Even. The tree species distribution was the same for trees with a diameter > 5 cm a breast height (bh) in both parcels,> 95% pine. For trees <5 cm bh, the distribution in Uneven was 14 % pine, 10 % spruce and 76 % deciduous, in Even there were almost exclusively deciduous trees. When examining pine > 5 cm at bh, there was a significant difference in the knot quantity with fewer knots/m in Uneven than in Even. The thickest knot was smaller in Uneven than in Even, but the difference was only significant when the data without dominants was examined. The thickest knot was slightly smaller relative to the diameter of the trunk in bh in Uneven but the difference was not significant. The average diameter in pine > 5 cm at bh was slightly less in Uneven, 10.7 cm, than in Even, 10.8 cm. The survey gives an indication that the layered forest according to the method of “Naturkultur” in the parcel Uneven, where dominants shades smaller trees, may be used for a better timber quality in pine in the investigated premises. However, the results are not sufficiently clear, if this is due to the fact that the quality difference is small or if it is because quality differences have not yet occurred V cannot be read in the survey. Estimating timber quality early in the rotation period is difficult as a lot can happen until final felling. However, the survey has been valuable as more data is needed in the area in question. Follow-up of the survey is needed to further explore the relationships between stock treatments and quality development.

  • 13.
    Andertun, Rickard
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Aptering för högre medellängder på massavedssortimenten2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    För att transporterna skall bli mer ekonomiska och samtidigt ha en liten miljöpåverkan krävs det att maximera transporterna viktmässigt och minimera avstånden. Ett tillvägagångssätt för att utnyttja lastkapaciteten är att ha en hög medellängd på virket för att transportera mindre luft i den begränsade volymen på lastbilen. Den här studien undersöker medellängder på massaved hos Sydved. Sydved har ett miljömål där 90% av volymen skall hålla minst 4,2 m medellängd på barr, gran och lövmassaved. En ökad medellängd på massaveden får inte påverka timmerutbytet eftersom det primära skall vara att aptera för bästa ekonomi för markägaren. Studien undersöker om och hur aptering för en ökad medellängd på massaved av gran påverkar timmerutbytet. Studien resulterar i att aptera massaveden till högre medellängder för att nå miljömålet kan påverka timmerutbytet både positivt och negativt.

  • 14.
    Bahr, Adam
    et al.
    Lund University, Sweden.
    Ellström, Magnus
    Lund University, Sweden.
    Bergh, Johan
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Wallander, Håkan
    Lund University, Sweden.
    Nitrogen leaching and ectomycorrhizal nitrogen retention capacity in a Norway spruce forest fertilized with nitrogen and phosphorus2015In: Plant and Soil, ISSN 0032-079X, E-ISSN 1573-5036, Vol. 390, no 1-2, p. 323-335Article in journal (Refereed)
    Abstract [en]

    Aims

    To estimate the production of external ectomycorrhizal mycelia (EMM) in Norway spruce forests with varying nitrogen (N) and phosphorus (P) levels, and to relate this to the N retention capacity of ectomycorrhizal fungi (EMF) and N leaching.

    Methods

    Seasonal changes in EMF production (in ingrowth mesh bags) and soil water N (in suction lysimeters) were analyzed after fertilization with N or N combined with P. The EMF N retention capacity was estimated by the addition of isotopically labeled N to the mesh bags.

    Results

    No relationship was found between the seasonal variation in EMF growth and N leakage from the soil. However, in the mesh bags, the total assimilation of 15N by EMF was almost halved by N fertilization, while twice as much 15N leached through.

    Conclusions

    We found a high specific N assimilation capacity per unit weight of EMF mycelia. This was unaffected by N fertilization, but the total assimilation of N by EMF was drastically reduced due to reduced production of EMM. However, N-retaining processes other than N assimilation by EMF must be taken into account to explain the losses of N after fertilization.

  • 15.
    Benjaminsson, Erik
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Åslund, Victor
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Höstplantering av tall - Ett komplement till vårplantering?2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project was conducted in spring 2017, commissioned by Södra forest association, to investigate whether autumn planting of pine gives a good regeneration result and can be seen as an equivalent alternative to planting in spring. Traditionally, most of the plantings is completed in spring, but in order to achieve a more even distribution of labor over the year, it is interesting to investigate whether or not the autumn planting of pine can be successful.

    The survey was carried out as a survey study, where plants planted both in autumn 2014 and in spring 2015, formed the basis of data collection. A total of 38 sites were investigated, half of study object were planted in spring and half in autumn Sites were then compared in pairs regarded to plant type, site index, game treatment, soil moisture and blockiness. On each site 20 plots were laid out with a radius of 2.82, which gives a sample area of 25 m2. In each sample area following characteristics for each plant were measured; stem diameter, leeding shot length, total length, possible damage and possible dead plants and cause of plant death.

    Autumn planting of pine had a higher mortality than spring plantations, and the pine weevil caused highest mortality, followed by wildlife grazing and drought. The plantation grew slightly better for spring-planted seedlings, but it was only the leeding shot length that had a significant higher growth. The damage caused by pine weevil was similar for planting in autumn and spring, while the wildlife grazing was twice as high in autumn-planted areas compared to the spring planted. 

  • 16.
    Berg, Linus
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Skogsägares och jägares syn på älgbetesskador i Jönköpings län2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Scots pine (Pinus sylvestris) is an important food source for the moose (Alces alces) during winter. Scots pine is also one of the most important tree species for the Swedish timber- and pulpwood industry. The debate between hunters and forest owners, their thoughts about the magnitude of the moose population, and the extent of browsing damage, is background to this study that examined how the groups forest owners who hunts, forest owners who doesn’t hunt and hunters who doesn’t own any forest land thought about browsing damages and its consequences in Jönköping County, Sweden. Data was collected using a questionnaire and analyses were made on answers from 258 respondents. The results showed that the assessment of the extent of browsing damage differed significantly between the groups, where forest owners who doesn’t hunt assessed the extent of browsing damage the highest, hunters who doesn’t own any forest land assessed the extent as lowest, while forest owners who hunt was intermediate between the two other groups. The results also showed that there was a relation between how the respondents assessed the extent of browsing damage and their thoughts about how large the moose population should be.

  • 17.
    Bergh, Johan
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Skogsbruk2015In: Klimatsäkrat Skåne / [ed] Hall, M, Lund, E & Rummukainen, M, Lund, Sweden: Centrum för miljö- och klimatforskning, Lunds Universitet , 2015, p. 111-120Chapter in book (Other academic)
  • 18.
    Bergh, Johan
    et al.
    Swedish University of Agricultural Sciences, Sweden.
    Blennow, Kristina
    Swedish University of Agricultural Sciences, Sweden.
    Andersson, Mikael
    Swedish University of Agricultural Sciences, Sweden.
    Olofsson, Erika
    Swedish University of Agricultural Sciences, Sweden.
    Nilsson, Urban
    Swedish University of Agricultural Sciences, Sweden.
    Sallnäs, Ola
    Swedish University of Agricultural Sciences, Sweden.
    Karlsson, Matts
    Swedish University of Agricultural Sciences, Sweden.
    Effekter av ett förändrat klimat på skogen och implikationer för skogsbruket: Bilaga B 19, Arbetsrapport 342007In: Sverige inför klimatförändringarna: hot och möjligheter, Fritzes, 2007, p. 1-71Chapter in book (Other (popular science, discussion, etc.))
    Abstract [sv]

    Att klimatet kan komma att förändras påverkar svenskt skogsbruk. Skogen har i sig en direkt inverkan på klimatet samtidigt som skogsbruket kan behöva anpassas till de nya förhållandena. Ett osäkert klimat sätter brukandet av skogen i ett nytt läge som vi inte har någon tidigare erfarenhet av. Scenarier för framtida klimatutveckling är behäftade med stor osäkerhet och de förväntade effekterna på skogen blir således ännu mer osäkra. Trots detta kan man ändå förutsäga några sannolika huvuddrag i effekterna på den svenska skogen vid ett framtida ändrat klimat. En ökad potential för biomassaproduktion kan förväntas, liksom ökade möjligheter att använda nya arter i skogsbruket. Samtidigt ökar sannolikt risken för vissa typer av skador.

    Att väga eventuella fördelar i form av ökad produktion och ökade möjligheter i trädslagsval mot ökade risker för skador är viktigt för att ge samhället ett helhetsperspektiv och för att en större grupp ska ha möjlighet att ta till sig frågan. Det är också viktigt att i största möjliga mån kvantifiera eller ge ramarna i ekonomiska termer för hur det förändrade klimatet kan tänkas påverka skogsbruket. Vidare kan det vara styrande för prioritering av fortsatta forskningsarbeten och riskbedömning och för att prioritera åtgärder. Därför har vi försökt utifrån befintlig kunskap idag, konstruera en Tabell över den ekonomiska betydelsen och forskningsbarheten för olika risk/ämnesområden (se Tabell 17 sidan 39). De kanske största effekterna av ett förändrat klimat på ekonomin inom skogsbruket skulle vara om vi lyckas utnyttja den ökade produktionspotentialen. Det förutsätter att vi kan bemästra de negativa effekterna i första hand av en ökad risk för vindfällning, skadeangrepp från insekter och svampar. Mot bakgrund av skogsbrukets stora betydelse som naturresurs och industriell bas, så finner vi att det är viktigt att vi står rustade inför en framtid med såväl ökade hot som nya möjligheter.

    I denna skrift försöker vi beskriva och analysera tänkbara effekter av ett förändrat klimat på skogen och bedömt deras implikationer för produktionsskogsbruket. Andra aspekter än produktionsaspekter på skogsbruket har inte behandlats. Analysen sker i fyra steg. Vi inleder med att, så långt nuvarande kunskapsläge tillåter, kvantifiera effekterna på den skogliga primärproduktionen – tillväxten i skogen. I ett andra steg omsätts dessa effekter till effekter på produktionsekonomin i ett bestånd. Därefter analyseras tänkbara effekter på risken för stormfällning i skogen. I ett sista steg breddas diskussionen till en något mera spekulativ bild av tänkbara effekter på skogsbrukets ekonomi.

  • 19.
    Bergh, Johan
    et al.
    Swedish University of Agricultural Sciences (SLU).
    Johansson, U
    Nilsson, U
    Sallnäs, O
    Är anpassning av skogsskötseln nödvändigt i dagsläget för att minska skogsskador i ett förändrat klimat? Del 1 – analyser på bestådsnivå2012Report (Refereed)
  • 20.
    Bergh, Johan
    et al.
    Swedish University of Agricultural Sciences (SLU).
    Johansson, Ulf
    Jönsson, Anna Maria
    Lund University.
    Lagergren, Fredrik
    Lund University.
    Lundström, Anders
    Nilsson, Urban
    Sallnäs, Ola
    Är anpassning av skogsskötseln nödvändigt i dagsläget för att minska skogsskador i ett förändrat klimat?: Del 2 –analyser på regional nivå2012Report (Other academic)
  • 21.
    Bergh, Johan
    et al.
    Swedish University of Agricultural Sciences.
    Nilsson, Urban
    Swedish University of Agricultural Sciences.
    Allen, H Lee
    North Carolina State University, USA.
    Johansson, Ulf
    Swedish University of Agricultural Sciences.
    Fahlvik, Nils
    Swedish University of Agricultural Sciences.
    Long-term responses of Scots pine and Norway spruce stands in Sweden to repeated fertilization and thinning2014In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 320, p. 118-128Article in journal (Refereed)
    Abstract [en]

    Recent investigations have shown that annual wood production in Sweden can be increased by 30 million m3 per year in a long-term perspective (>50 years) by using new forest management methods such as new tree species or seedling materials. However, to meet the increased demands during the next 20 years, Sweden will have to rely on silvicultural methods available today. Growth in boreal and cold temperate forest is with only few exceptions limited by nutrients availability, primarily nitrogen, and one way to satisfy the increased demands in a short-term perspective is nitrogen fertilization. A set of thinning and fertilization experiments were started in the 1960’s in Scots pine and Norway spruce stands over the whole of Sweden representing different soil, moisture and vegetation types. We used data from these experiments to examine the long-term effects of repeated fertilization in thinned stands on growth, stand development, and yield. The 34 Scots pine sites and 13 Norway spruce sites included in our analyses had at least four treatment plots (no thinning, repeated light thinnings, repeated light thinnings with repeated N fertilization, and repeated light thinnings with repeated N + P fertilization). In northern Sweden, 100 kg N ha−1 and 150 kg N ha−1 were applied at each fertilization event for Scots pine and Norway spruce stands, respectively. In southern Sweden, 150 kg ha−1 N was applied in Scots pine stands and 200 kg ha−1 N in Norway spruce stands. Phosphorus was applied at the rate of 100 kg ha−1. Several sites also included non-thinned fertilized plots. Pine stands but not spruce stands were responsive (up to 25% more growth depending of the attribute assessed) to repeated fertilization. Surprisingly, the non-thinned pine stands showed strong continuing response to fertilization throughout the 30+ year observation period resulting in higher cumulative volume response than the thinned stands. In thinned stands incremental volume response to fertilization continued but slowly diminished with time indicating that fertilization and thinning effects were less than additive. However, thinning and fertilization effects were additive for diameter growth. Fertilization accelerated stand development with significant shifts in diameter distributions to larger and potentially more valuable trees. Conclusively, repeated nitrogen fertilization is a silvicultural practice that will result in significant and sustained increases in Scots pine production.

  • 22.
    Bergh, Johan
    et al.
    Swedish University of Agricultural Sciences (SLU).
    Nilsson, Urban
    Kjartansson, Bjarki
    Karlsson, Matts
    Impact of climate change on the productivity of Silver birch, Norway spruce and Scots pine stands in Sweden with economic implications for timber production2010In: Ecological Bulletins, ISSN 0346-6868, Vol. 53, no 16, p. 185-195Article in journal (Refereed)
  • 23.
    Berglind, Lennart
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Skogsägares uppfattning om tillväxtdata i skogsbruksplaner2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    SAMMANFATTNING

    Skogens tillväxt är naturligtvis en central och grundläggande aspekt i skogsbruk

    och själva grunden för ett lönsamt skogsägande. Frågan är i vilken utsträckning

    skogsägare använder sig av data om tillväxt i skogsbruksplaner, och om de

    upplever att dessa uppgifter är väsentliga och användbara. Eller kan det finnas

    alternativa sätt att presentera tillväxt och kanske även annan typ av information i

    skogsbruksplanerna som bedöms som minst lika värdefull?

    Denna studie försökte främst ta reda på vilken tilltro skogsägarna fäster vid data

    om tillväxt i skogsbruksplaner. Svaren pekade mot att skogsägarna hyste en

    relativt stor tilltro till tillväxt angivet som ett numeriskt värde (3,47 av 5 poäng)

    och även till dess substantiella informationsvärde, men att även annan

    beståndsinformation som exempelvis åtgärdsförslag bedömdes som minst lika

    viktig.

    Felkällorna vid bestämning av ståndortsindex och bonitet kan vara ganska

    betydande, och det mest osäkra är vid översättning från ståndortsindex till

    bonitet. Detta kan sedan bidra till att ge en felaktig bild av värden på tillväxt,

    liksom det faktum att kvaliteten på, och användbarheten av inventeringsdata

    tydligt försämras över tid.

    Det är tydligt att det är svårt att sätta en sann siffra på kommande skoglig

    tillväxt. Kanske är det mest tillförlitligt att ange tillväxt som ett relativt värde i

    procent av aktuell stående volym, och som uppskattas för exempelvis fem år

    framåt? Att ange tillväxten i m3sk/ha och år kan ses som mera oprecist och

    momentant. Visarprocent kan vara en användbar indikator i skogsbruksplaner på

    den tillväxt som finns i bestånden, och som avser att genom rangordning jämföra

    olika bestånds räntabilitet. Ett annat sätt att beskriva beståndens utveckling mot

    timmerträd kan vara att skapa ett värde för formtalsutvecklingen, och att

    skogsägaren därmed på sikt kan jämföra dessa värden med tidigare mätningar.

    Det kan vara intressant för en skogsägare med en nyupprättad plan att få muntlig

    information om begreppen bonitet, tillväxt, visarprocent och formtal, och hur de

    konkret kan kopplas till den egna skogsmarken på både bestånds- och

    fastighetsnivå vid inventeringstillfället. Det bör vara ett bra läge vid den

    tidpunkten att erbjuda dessa upplysningar, troligen som en debiterad

    tilläggstjänst i samband med planläggningen.

    En tydlig insikt av studien är att det är just den säkerställda kvaliteten på

    beståndsdata, liksom hur färska inventeringsdata är, som är de enskilt viktigaste

    faktorerna för att få högkvalitativ information om inte minst skoglig tillväxt i

    skogsbruksplaner

  • 24.
    Berglund, Marie
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Röjningsformen och stamantalets effekt på höjd- och diametertillväxt i toppröjda och konventionellt röjda tallbestånd.2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Topping is a precommercial thinning (PCT) method where secondary stems are cut higher above the ground compared to conventional PCT. The secondary stems continue to live for a period and are supposed to compete with the main stems and promote their quality.

    The objective of the study was to compare the effect of PCT on height and diameter growth between topping and conventional PCT. The study also analysed the relationship between height and diameter growth and the number of stems after PCT.

    Nine topped stands and six conventional precommercially thinned stands were visited between February 28th and March 5. One sample plot per hectare was laid out in the investigated stands. In every sample plot the number of stems was counted and five main stems were measured for height, height growth since PCT, diameter and diameter growth since PCT.

    The results showed significantly higher effect on height growth after topping as compared to conventional PCT but no significant difference in the effect of diameter growth between topping and conventional PCT. After PCT the H/D quote (height/diameter quote) was higher (less taper) in topped stands and lower (larger taper) in conventional PCT.

  • 25.
    Berlin, Mats
    et al.
    Uppsala Science Park.
    Sonesson, Johan
    Uppsala Science Park.
    Bergh, Johan
    Swedish University of Agricultural Sciences (SLU).
    Jansson, Gunnar
    Uppsala Science Park.
    The effect of fertilization on genetic parameters in Picea abies clones in central Sweden and consequences for breeding and deployment2012In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 270, p. 239-247Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to analyze the effect of repeated fertilizer application on the genetic parameters of Norway spruce. Genetic and environmental variances of growth and phenological traits were estimated to find differences between fertilized and control treatments in broad sense heritability and accuracy of estimated genotypic value. Furthermore, genotype × environment interactions (GxE) between the two treatments were investigated. Two Norway spruce clonal field trials in central Sweden were subjected to both treatments and were measured at various points in time up to a field age of 15 years, to monitor the effects of fertilization. For growth traits, trees in the fertilized treatment exhibited lower environmental variance than those in the non-fertilized treatment; consequently, fertilization yielded higher heritability and greater accuracy of estimated genotypic value. Furthermore, the GxE increased as the effects of fertilization became more pronounced; the genetic correlation between treatments dropped to around 0.5 in the last measured growth period. For phenological traits, no GxE but a slight increase in heritability of prolepsis on the leader shoot was found. The results from this study show that, for the conditions encountered in central Sweden, Norway spruce clones should be tested and selected under the conditions in which they are to be deployed. If repeated fertilizer application is to be adopted under operational conditions, substantial losses in genetic gain for growth can be expected when using current selected clones due to the induced GxE. While the fertilized treatment yielded a higher heritability and accuracy of estimated genotypic value for growth traits than did the control, the Swedish Norway spruce breeding program will not benefit from fertilizing genetic field trials because the increased accuracy of estimated genotypic value is nullified by the GxE.

  • 26.
    Björcman, Frida
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Drivkrafter, innehåll och upplevelser av aktivism i skogliga konflikter2019Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Situations and behaviors can create conflicts between people and/or organizations based on a need of resources or a conflict of interest. Using activism in a conflict can be value based and is driven by a person's opinions and norms. The changed forest policy since the seventies has resulted in a greater interest in protecting forests, both from the authorities and from interest groups. The high proportion of privatelyowned forests and the increased interest have created several major conflicts over thepast ten years in Sweden, where the land owner has ended up between interest groups and authorities.The study aims to explain and create an understanding of how different sides reason in forest conflicts with activism, based on content, driving forces and experiences. Data-collection was done through 8 deep interviews. Respondents belonged to a government agency, three forest companies / forest owner associations, two individual forest owners and two nature conservation organizations. Thematic content analysis was performed on the collected material.There were differences in the value base where authorities and landowners did not value the ecological values as important to the same extent as forest companies/forest owner associations and interest groups, which in turn creates a risk of conflicts. About future activism, four respondents considered that it would increase, while three felt that it would decrease and one that it will be like today. In seven out of eight cases, it was an interest organization that initiated the conflict. Authorities, forestry companies / forest owner associations and landowners all considered that the information received from the interest groups was a good basis. A driving force that was identified was the need to assume responsibility, which originates from the driving force. The action in the conflicts was defined by the interest groups as a responsibility, while the parties who had experienced the activism defined the action as a high pressure. The experiences of activism that emerged were described by the landowners as an unpredictability and the interest groups as a vulnerability because of their deviant opinion. Authorities and forestrycompanies/forest owner associations described activism as a reluctance/ignorance. The negative and positive aspects of activism weigh in principle equally for all respondents. Authorities, interest groups and forestry companies/forest owner associations all mentioned a need for system change, as the political short-term and the inertia of the system was emphasized as a problem. From all sides a collaboration was desired, where a factual dialogue must be the basis. One can ask how important the interest organizations are for the development of forestry when the material produces by them is considered good quality? And is it the forest owners who must get run overwhen the policy is short-term? Forestry companies/forest owner associations and authorities report their responsibility towards the citizens and that there were information deficiencies. By improving the dialogue and the information there is an opportunity to find ways to reach each other. This is to get a better overall view of how the different sides reason and what everyone's values are. Based on this, conflicts can hopefully be fewer in the Swedish forests.

  • 27.
    Björkemar, Kristian
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Agroforestry in Sierra Leone –examining economic potential with carbon sequestration2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis aimed to examine the possibilities and benefits of implementing

    agroforestry projects in Sierra Leone by comparing different agroforestry

    systems used in a Tanzanian project that consider carbon sequestration.

    Farmers involved in this type of projects get income from sold carbon

    credits as well as from other products that an agroforestry system could

    provide.

    Sierra Leone is one of the most vulnerable countries to climate change, with

    most of the population living in rural conditions. It was investigated what

    the potential economic and environmental impact different agroforestry

    systems considering carbon storage could have in Sierra Leone. The study

    was based on empirical material from a case community Makari. The

    conclusions were that Sierra Leone could benefit greatly from agroforestry

    projects, especially at community level where it could provide additional

    sources of food and income. From a greater perspective it could give

    environmental benefits as well as securing wood commodities like fuelwood

    for the future. Starting up a project would however be a high risk investment

    with a troublesome implementation process and complications on a daily

    basis.

  • 28.
    Björkman, Frida
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Schubert, Björn
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Målbildsuppfyllelse vid ungskogsröjning i kantzoner mot sjöar och vattendrag i Västra Götalands Jönköpings och Hallands län2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The study examined the goal fulfillment in edge zones along rivers and lakes in precommercial thinning stands based on national targets which is the basis for Swedish forestry. Pre-commercial thinning has a major impact on the future forest, as it determines how the tree species distribution will turn out. The study was conducted as a field study in February 2018 based on 30 precommercial thinning sites, aged 5–15 years, in connection to rivers and / or lakes. Of these, 25 rivers and five lakes were surveyed. 22 of the surveyed stands were privately owned and 8 were company-owned forests. The edge zones had between 0–100% shadowing of the water surface. Few sites with soil damage were detected and also a varying amount of tree species and deadwood. The most common deadwood was standing and lying dead wood with a diameter of 10 cm for both company and privately-owned forests. The percentage of number of stems per ha of deciduous trees in the edge zones was 52%, Norway spruce 41% and Scots pine 7% respectively. Within the edge zones, the sample areas closest to rivers and lakes had 55% of number of stems per ha deciduous trees, 40% spruce and 6% pine. In the sample areas closest to the stand, the number of deciduous trees was 48%, spruce 44% and pine 9%. Company-owned forests had more spruce (59%) along the waterfront compared to privately owned forests, who had a significantly higher proportion of deciduous trees (61%). By actively working with the composition of the edge zones, creating deadwood, saving trees for shadow and by thinning dense areas, particularly spruce-dominated, increased biodiversity can be achieved. Dense, spruce-dominated areas are those areas where the goal fulfillment is insufficient in many places.

  • 29.
    Blennow, Kristina
    et al.
    SLU.
    Andersson, Mikael
    SLU.
    Sallnäs, Ola
    SLU.
    Olofsson, Erika
    SLU.
    Climate change and the probability of wind damage in two swedish forests2008In: Adaptation of Forests and Forest Management to Changing Climate with Emphasis on Forest Health: a Review of Science, Policies, and Practices., Umeå, 2008, p. 39-Conference paper (Other academic)
  • 30.
    Blennow, Kristina
    et al.
    Sveriges Lantbruksuniversitet (SLU).
    Andersson, Mikael
    Sallnäs, Ola
    Olofsson, Erika
    Linnaeus University, Faculty of Science and Engineering, School of Engineering.
    Climate change and the probability of wind damage in two Swedish forests2010In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 259, p. 818-830Article in journal (Refereed)
    Abstract [en]

    We simulated how possible changes in wind and ground-frost climate and state of the forest due to changes in the future climate may affect the probability of exceeding critical wind speeds expected to cause wind damage within one northern and one southern study area in Sweden, respectively. The topography of the study areas was relatively gentle and the forests were dominated by Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.). Using estimated changes in the net primary production (NPP) due to climate change and assuming a relative change in the site productivity equal to a relative change in NPP, we simulated possible future states of the forest under gradual adjustment of the site index in response to climate change using the model The Forest Time Machine. Global climate change scenarios based on two emission scenarios and one general circulation model were downscaled to the regional level. The modified WINDA model was used to calculate the sensitivity of the forest to wind and the probability of wind damage for individual forest stands for the periods 2011–2041 and 2071–2100 and for a control period 1961–1990. This was done while taking into account effects on stability of the forest from expected changes in the occurrence of ground frost. Increasing sensitivity of the forest to wind was indicated for both study areas when adhering to recommended management rules of today. Adding also a changed wind climate further increased the probability of wind damage. Calculated probabilities of wind damage were generally higher in the southern study area than in the northern one and were explained by differences in wind climate and the state of the forests, for example with respect to tree species composition. The indicated increase in sensitivity of the forest to wind under the current management regime, and possibly increasing windiness, motivate further analysis of the effects of different management options on the probability of wind damage and what modifications of Swedish forest management are possibly warranted.

  • 31.
    Blennow, Kristina
    et al.
    SLU.
    Olofsson, Erika
    SLU.
    Att gallra eller inte gallra - det är frågan2002In: Osäkerhet och aktiv riskhantering, SUFOR , 2002, p. 8-10Chapter in book (Other academic)
  • 32.
    Blennow, Kristina
    et al.
    Swedish University of Agricultural Sciences.
    Olofsson, Erika
    Swedish University of Agricultural Sciences.
    Kan man undvika stormskador?2004In: Osäkerhet och aktiv riskhantering: aspekter på osäkerhet och risk i sydsvenskt skogsbruk / [ed] Kristina Blennow, Alnarp: Sustainable Forestry in Southern Sweden (SUFOR) , 2004, 1, p. 39-43Chapter in book (Other academic)
  • 33.
    Blennow, Kristina
    et al.
    SLU.
    Olofsson, Erika
    SLU.
    Models for predicting the probability of wind damage as decision support in forest management2003In: Decision support for multiple purpose forestry: a transdisciplinary conference on the development and application of decision support tools for forest management, Vienna: University of Natural Resources and Applied Life Sciences , 2003Conference paper (Other academic)
  • 34.
    Blennow, Kristina
    et al.
    Swedish University of Agricultural Sciences, Sweden.
    Olofsson, Erika
    Swedish University of Agricultural Sciences, Sweden.
    Sallnäs, Ola
    Swedish University of Agricultural Sciences, Sweden.
    Evaluating WINDA: a tool for assessing the probability of wind damage to forest stands2003In: Proceedings of the International Conference Wind Effects on Trees: 16-18 September 2003, University of Karlsruhe, Germany / [ed] B. Buck, C. Kottmeier, C., Mattheck, C. Quine, G. Wilhelm, 2003, p. 137-144Conference paper (Other academic)
    Abstract [en]

    WINDA is an integrated system of models for calculating the stand-wise probability of wind damage of trees within a landscape (Blennow & Sallnäs, submitted). It integrates a modified version of the dose/response model HWIND (Peltola et al., 1999), the airflow model WASP (Mortensen et al., 1998), and a component for calculating the zero-plane displacement and surface roughness. WINDA uses a GIS for geographical computations. The calculations are made point-wise at exposed stand edges and the results are combined for each stand. The likelihood of damage is calculated using extreme value theory. The mechanistic modelling approach makes WINDA useful for evaluating effects on the probability of wind damage of silvicultural treatments and forestry activities as well as of a changed climate. This paper briefly outlines WINDA and evaluates output by comparing predicted damage with observed damage for two landscapes in southern Sweden.

  • 35.
    Blom, Henrik
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Carl, Arnström
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Årsringsutvecklingens betydelse för produktion av granvirke av kärnved  2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med denna studie var att undersöka möjligheten att producera virke av gran som enbart består av kärnved och därmed öka kvaliteten för fasadvirke.

    För att uppnå syftet har flera olika metoder kombinerats. Metoderna var enkät, analys av data från experiment, simulering och validering.

    Kärnvedens diameter beror på ålder/antal årsringar och årsringsbredd. Bredare årsringar närmst märgen innebär en större diameter kärnved vid kärnvedsbildningen och en större diameter kärnved vid avverkning.

    Det är möjligt att producera virke av gran som enbart består av kärnved. Det innebär emellertid att omloppstiderna kan behöva bli längre för att uppnå dimensioner av 120 – 195 mm breda brädor och reglar. Avgörande för kärnvedsandelen är tillväxten i ungdomen där årsringarna är som bredast.

  • 36.
    Blomqvist, Lars
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Shape stability of laminated veneer products2013Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis is about the shape stability of laminated veneer products.

    Laminated veneer products consist of veneers bonded together with adhesive into a predetermined shape. Such products are used in several contexts but especially in furniture manufacture. Deviation from the intended shape is a problem for both manufacturers and customers of the final products. The shape stability of laminated veneer products depends on a variety of material and process parameters, and this thesis identifies several important factors that influence shape stability. The purpose of this thesis is to find ways to decrease distortion and improve shape stability so that product quality can be improved.

    Different ways of measuring shape stability, both in an industrial environment and in a more research-based context, are presented in this thesis. Various studies have been conducted to evaluate the influence of different material and process parameters on shape stability. The parameters studied were species (beech and birch), adhesive system (bio-based adhesives, adhesive systems based on urea formaldehyde), adhesive distribution on the veneer, climate, moisture content and fibre orientations of the veneers, as well as orientation of the individual veneers in an assembly.

    The results clearly show that the fibre orientation of the veneer strongly influences the shape stability of a laminated veneer product. This means that products can show considerable distortion (particularly twist) if the fibre orientation of the veneer is orientated in an unsuitable way in the assembly before moulding. The effect of fibre orientation on shape stability can be very small directly after moulding, but it increases considerably when the moulded product is subjected to a change in moisture content. In general, a change in moisture content leads to distortion. Moisture change alone, however, results in a controlled distortion.

    An asymmetrical construction coupled with different moisture contents of the veneers in an assembly before moulding will result in poor shape stability of the product. Other studied parameters had a low impact on shape stability, although beech resulted in more distortion and poorer shape stability than birch.

    In order to produce shape-stable laminated veneer products, the veneers should be conditioned to a uniform moisture content and sorted with regard to fibre orientation before bonding. The orientation of the veneers is highly important regarding both fibre orientation and the loose or tight side of the veneer. If shape stability is the main target, the loose sides of peeled and sliced veneers should be oriented in the same manner.

  • 37.
    Blomqvist, Lars
    Växjö University, Faculty of Mathematics/Science/Technology, School of Technology and Design.
    Simulering och mätning av yttryck vid formpressning2008Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
  • 38.
    Blomqvist, Lars
    et al.
    Trätek.
    Hagström, Lina
    Trätek.
    Oscarsson, Jan
    Trätek.
    3D-modeller i träindustrin som konkurrensmedel vid e-handel2002Report (Other academic)
  • 39.
    Blomqvist, Lars
    et al.
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Johansson, Jimmy
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Sandberg, Dick
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Shape stability of laminated veneer products: an experimental study of the influence on distortion of some material and process parameters2013In: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280, Vol. 8, no 3, p. 198-211Article in journal (Refereed)
    Abstract [en]

    Laminated bending of veneers is a common used and important process for manufacture of components primarily for furniture and interior purposes. According to the use, such products are in general very sensitive to variations in the intended shape, i.e. distortion can be of great problem and more or less destroy the use of the final product. The most critical mode of distortion is twist, but also other changes in shape may be of interest to keep low. The causes to distortion of laminated bended veneer products can be of material (veneer, adhesive and the combination of these), design, processes and climate nature and there is a challenge to know which parameters which are of major importance for distortion, both directly after moulding and when the products are in use.

    In this study, the influence of type of UF-adhesive hardener, i.e. liquid or powder, water content of adhesive, adhesive distribution, variation of moisture content of glued veneers, and fibre orientation of veneers, on twist and position for a 3D-veneer construction (a chair seat shell) has been studied. Distortion, i.e. twist and position, has been determined directly after moulding and after moisture cycling. The moisture cycling was to simulate and accelerate conditions that the shells are subjected in use. The aim of the work is to study how the above mentioned material and process parameters influence the shape stability of the products.

    The results show that the climate, i.e. how a certain level of temperature and relative humidity influence the moisture content of the moulded product, has a clear impact on the distortion of the product in use. An increase in moisture content results in a significant increase in distortion and vice versa. The level to which the moulded products distort during climate variation can be controlled through controlling material, design and process parameter during moulding. Of the studied parameter mentioned above, a deviation in fibre orientation of the veneers in the moulded assembly is the most critical parameter to have under control to minimize distortion. The fibre deviation mainly results in an increase in twist. A high moisture content of a veneer vis-à-vis the rest of the veneers in the assembly before moulding, will result in increased position and twist of the moulded product in use. The difference of moisture content between veneers and the position of veneers with high moisture content in the assembly will influence the level of distortion. Other studied parameter also influences the distortion to a lesser extent and can in these cases be related to the moisture distribution in the mouldings.

  • 40.
    Blomster, Karina
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Privata skogsägares benägenhet till röjning i Gudrunområdet: En kvalitativ intervjustudie2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study was to examine how small-scale private forest owners

    make decisions regarding pre-commercial thinning. In 2015 it is ten years ago

    since the storm Gudrun hit the southern parts of Sweden and now large areas are

    in need of pre-commercial thinning. This study is built upon qualitative

    interviews with seven small-scale private forest owners with forest properties in

    the county Kronoberg. The respondents were chosen by the model

    SKOGSÄGARPROFILENTM (forest owner profile).

    The results of the interviews showed that five categories: ownership, the storm

    Gudrun´s impact, silviculture, forestry contacts and driving force was important.

    How will their purpose and aim affect the pre-commercial thinning? Personal

    interests, and expectations of the next generation to take over, are purposes this

    study has found. Furthermore, when pre-commercial thinning is not carried out

    or postponed, the silviculture has got lower priority, and other chores higher

    priority. Lack of knowledge might be one issue. If so, a contact with someone

    with this knowledge is important for starting up the pre-commercial thinning.

    Key words: Gudrun clearing, pre-commercial thinning, personal interest, net of

    contacts, private forest owners, change-of generation, “forest owner profile”.

  • 41.
    Boje, Lis
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Filmen om skogen i skolan: Utomhusövningar som anknyter till skolans läroplan. Kännedom om skog och natur har bäring på människans livskvalite. Den svenska skogen är en del av vårt kulturarv och har i alla tider varit ett rum för avkoppling, friluftsliv och rekreation.2016Other (Other (popular science, discussion, etc.))
  • 42.
    Boje, Lis
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Ökad jämställdhet bland skogsägare2013Report (Other academic)
  • 43.
    Bonarski, Jan T.
    et al.
    Polish Academy of Sciences, Poland.
    Kifetew, Girma
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Olek, Wieslaw
    Poznań University of Life Sciences, Poland.
    Effects of cell wall ultrastructure on the transverseshrinkage anisotropy of Scots pine wood2015In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 69, no 4, p. 501-507Article in journal (Refereed)
    Abstract [en]

    A hypothesis for explaining the differential anisotropicshrinkage behavior of wood has been proposed,and it was based on the differences in the cell wall ultrastructure.The starting point of the consideration is thatwood shrinkage is governed by its chemical composition,ultrastructure, and gross anatomy. It is also well knownthat the transverse shrinkage anisotropy of earlywood(EW) is more pronounced than that of the latewood (LW).In the paper, the cell wall ultrastructure and shrinkageanisotropy has been related to each other, and to thispurpose, a set of crystallographic texture descriptorswas applied. The descriptors are based on X-ray diffraction(XRD) experiments conducted on matched EW samplesfrom different growth rings of Scots pine. The rangeof the microfibril angle (MFA) was identified. The ratio ofthe maxima of inverse pole figures (IPFs) of both the tangential(T) and radial (R) directions was determined. Theratios quantify the inhomogeneity of the spatial arrangementof the ordered areas. The results of the study clearlyindicate that the transverse shrinkage of wood is governedmostly by a specific ultrastructural organization of moderatelyorganized cell wall compounds.

  • 44.
    Bradshaw, R.H.W.
    et al.
    Dept. of Quaternary Geology, Geol. Surv. of Denmark and Greenland, Øster Voldgade 10, DK-1350 Copenhagen K, Denmark .
    Wolf, Annett
    Linnaeus University, The University Administration.
    Møller, P.F.
    Long-term succession in a Danish temperate deciduous forest2005In: Ecography, Vol. 28, no 2, p. 157-164Article in journal (Refereed)
    Abstract [en]

    Forest successional trajectories covering the last 2000 yr from a mixed deciduous forest in Denmark show a gradual shift in dominance from Tilia cordata to Fagus sylvatica and a recent increase in total forest basal area since direct management ceased in 1948. The successions are reconstructed by combining a fifty-year record of direct tree observations with local pollen diagrams from Draved Forest, Denmark. Five of the seven successions record a heathland phase of Viking Age dating from 830 AD. The anthropogenic influence is considerable throughout the period of study even though Draved contains some of the most pristine forest stands in Denmark. Anthropogenic influence including felling masks the underlying natural dynamics, with the least disturbed sites showing the smallest compositional change. Some effects of former management, such as loss of Tilia cordata dominance, are irreversible. Artificial disturbance, particularly drainage, has accelerated and amplified the shift towards Fagus dominance that would have occurred on a smaller scale and at a slower rate in the absence of human intervention. Copyright © Ecography 2005.

  • 45.
    Broo, Matilda
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kantzoners påverkan på höjd- och diametertillväxt samt markvegetationens artsammansättning hos angränsande tallbestånd i sydöstra Sverige2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Several studies carried out in boreal forests have found significant edge effects in Scots pine although, none of them in southern Sweden. The aim of this study was to investigate edge effects in adjacent Scots pine stands and its influence on tree growth and field vegetation composition. This was carried out in 10 selected forest edges in southeastern Sweden. Results showed reduced number of stems, height, diameter and basal area growth among young trees in particular within 2 m from the forest edge. In the older stands number of stems, diameter and basal area growth increased within the first 2 m from the edge. Field vegetation inventory showed differences in composition in the adjacent stands. In the older stands lichens, lingonberry and blueberry were more frequent, while heather and grasses showed a higher appearance in young stands.

  • 46.
    Bylund, Anna-Ida
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Kolbalansen vid olika skötselstrategier för skogen på Tagels fastighet.2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Since the 19th century the concentration of CO2 in the atmosphere hasincreased by 40 percent as an effect of the use of fossil energy sources.Increased concentration of CO2 will likely lead to increased temperature,changes in precipitation, rising sea level and increased frequency of extremeweather like storm events. A step to reduce emissions of CO2 and mitigateclimate change, for the property of Tagel, can be to adopt new silviculturalstrategies and analyse which is the most effective. As a result of that, threescenarios was produced, business-as-usual (BAU), increased set aside landand energy. An introduction of windpower at Tagels estate (property) andeffects on carbon balance was also examined. By using the Heureka systemand LCA-analysis in this study, it showed that the scenario of increased setaside land was the most efficient way to reduce carbon dioxide (CO2)emissions for the analysed period of 100 years. The effect of substitution(replacing for example fossil fuel or energy consuming building materials,with renewable raw material such as biomass) didn’t give the result that waspredicted. It appears that the use of pulpwood is very important, if it goes tothe pulp industry no substitution effect occurs, but if all pulp will be used forbioenergy purposes, the energy scenario will be the best in terms of overallcarbon balance. The stored carbon in tree biomass over and in roots wasaffected by all scenarios. The soil carbon was almost the same for allscenarios. In the future the property of Tagel can still use the alternativeBAU as an effective way to mitigate climate change but then explore thepossibilities to use the pulp for bioenergy purposes instead and to set asidemore land at the property. This study considered to have high credibilitybecause the Heureka-analyses, LCA and the substitution model were carriedout by experts in area of research.

  • 47.
    Carlberg, Stefan
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Lärkvirkets marknad i Sverige2017Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [sv]

    Trädslaget lärk introducerades i Sverige av Carl von Linné 1754 och var till en början avsett för virke till flottans fartyg. Denna studie fokuserar på hybridlärk (Larix eurolepis) och sibirisk lärk (Larix sibirica) för att undersöka och belysa marknaden för lärk i Sverige. Studien använder sig av en enkätundersökning till olika respondentgrupper inom skogsbranschen samt litteraturstudier. Resultatet visar att det existerar en marknad för lärk i Sverige men att den är mycket liten och relativt lokal och nischad. Skogsägarna är ovetande om såväl lärkens fördelar som nackdelar vid skogsodling, vilket kunde avhjälpas genom att skogsbolagen och de berörda myndigheterna ökade informationen till skogsägarna. Avsättningen för virket av lärk är för tillfället dåligt betalt, vilket är en anledning till att lärken inte är så populär bland landets skogsägare men kan marknaden och efterfrågan av lärkträprodukter expanderas uppstår incitament för ökad skogsodling på sikt.

  • 48.
    Cederlöf, Gunnel
    Uppsala University.
    Forests and Ecological History of Assam, 1826-2000 by Arupjyoti Saikia: Oxford University Press, New Delhi, 20112012In: Seminar New Delhi: a monthly symposium, ISSN 0971-6742, Vol. Dec, no 640Article, book review (Other academic)
  • 49.
    Cintas, Olivia
    et al.
    Chalmers University of Technology, Sweden.
    Berndes, Göran
    Chalmers University of Technology, Sweden.
    Hansson, Julia
    Chalmers University of Technology, Sweden;IVL Swedish Environmental Research Institute, Sweden.
    Poudel, Bishnu Chandra
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Bergh, Johan
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Börjesson, Pål
    Lund University, Sweden.
    Egnell, Gustaf
    Swedish University of Agricultural Sciences, Sweden.
    Lundmark, Tomas
    Swedish University of Agricultural Sciences, Sweden.
    Nordin, Annika
    Swedish University of Agricultural Sciences, Sweden.
    The potential role of forest management in Swedish scenarios towards climate neutrality by mid century2017In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 383, no Special Issue, p. 73-84Article in journal (Refereed)
    Abstract [en]

    Swedish climate policy targets net zero greenhouse gases (GHG) by mid-century, with road transport independent of fossil fuels by 2030, requiring far-reaching changes in the way energy is used. Forest management is expected to support carbon sequestration and provide biomass for various uses, including energy. In this paper, we combine two energy scenarios with four forest scenarios and quantify GHG balances associated with energy-use for heat, electricity, and road transport, and with forest management and production, use, and end-of-life management of various forest products, including products for export. The aggregated GHG balances are evaluated in relation to the 2-degree target and an allocated Swedish CO2 budget. The production of biofuels in the agriculture sector is considered but not analyzed in detail.

    The results suggest that Swedish forestry can make an important contribution by supplying forest fuels and other products while maintaining or enhancing carbon storage in vegetation, soils, and forest products. The GHG neutrality goal is not met in any of the scenarios without factoring in carbon sequestration. Measures to enhance forest productivity can increase output of forest products (including biofuels for export) and also enhance carbon sequestration. The Swedish forest sector can let Sweden reach net negative emissions, and avoid “using up” its allocated CO2 budget, thereby increasing the associated emissions space for the rest of the world.

  • 50.
    Dahlén, Vilhelm
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Gödslings- och röjningseffekt på diameter och höjdutveckling i en fågelbärsplantering i Nybro kommun2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Fågelbär räknas som ett av ädellövträden. Mot slutet av 1980-talet så började fågelbär planteras som virkesproduktionsträd i Sverige. Aktuell rapport bygger på en studie kring vilken effektgödsling och röjning har på fågelbärs höjdutveckling, diametertillväxt, antal kvist och kvistgrovleken. Mätresultaten samlades in mars-april 2018 från ett fågelbärsförsök lokaliserat i Nybro kommun, Småland. Vid analys av mätresultaten så gick det inte finna någon signifikant effekt av gödslingen på fågelbären. När effekten av röjningsåtgärderna studerades så gick det att finna en tydlig effekt på fågelbärens höjdtillväxt, diametertillväxt och högre antal kvist på stammen upp till två meter. Någon signifikant effekt på grövsta kvist upp till två meter på stammen gick dock inte att finna. Slutsatser som drogs av resultaten var att det inte gick finna stöd för att den genomförda gödslings åtgärden har någon effekt på volymproduktionen för fågelbär. Däremot gick det att finna stöd för att röjningsåtgärder har en betydande effekt på både höjd- och diametertillväxten för fågelbär. Naturligt föryngrad björk och asp växer dock snabbare än fågelbär.

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