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294 Uppsatser om Pine bark - Sida 1 av 20

Lakningsförsök med furubarksflis : en utredning om utsläpp av fenolföreningar samt metallsorption

The filters used today to purify water are often expensive and the need to find new filter materials is substantial. Studies of Pine bark have shown that this is a material that may be used as an alternative to conventional filter materials, such as activated carbon. However, the study of Pine bark has shown that a leakage of phenolic compounds may occur when using the material for water purification. Therefore, the purpose of this report is to investigate the release of phenols from Pine bark, in order to evaluate the use of Pine bark as a filter material. Another assignment is to investigate the amount of metals adsorbed by the filter material.

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..

Ett gammalt kulturlandskap i Vindelfjällen : skogshistoria och markutnyttjande i Vuornavagge under 300 år

Humans have inhabited mountainous areas in northern Sweden since the end of the last glacial period, ca 8000 B.P., and their presence has marked the landscape in various ways. Older traces include the remains of hearths and dwelling sites, but there are also remains, such as culturally modified trees (CMT's), resulting from more recent activities in forested areas. This study aimed to document how people, both indigenous Sami's and Swedish settlers, have used an area northwest of Ammarnäs in Västerbotten, during the last 300 years, and what traces their activities have left in the area. I used historical records as well as an inventory of CMT's in the area to address this aim. Historical records of Sami activity are meagre, but it is clear that the people of the Ran and Gran Sami villages utilized the area long before 1500 A.D.

Skogseldens påverkan på epifytiska trädlavar på tall i relation till brandintensiteten :

Not much is today known about how epiphytic lichens are effected by fire. A considerable part of the fires in Sweden today are prescribed fires for the purpose of environmental conservation. How these fires affect lichens is largely unknown. The aim of this study is to find out how epiphytic fruticose and foliose lichens on Scots pine are affected by fire, and to elucidate the relationship between fire intensity and the survival of lichens and later re-colonization. The study was performed at three locations just outside Umeå in Västerbotten that were burned 5-7 years earlier. In all locations there were larger groups of surviving Scots pines with varying amount of fire-damage in the crown, which enabled a reconstruction of fire intensity.

Samverkan på svenska mötesdestinationer.

Not much is today known about how epiphytic lichens are effected by fire. A considerable part of the fires in Sweden today are prescribed fires for the purpose of environmental conservation. How these fires affect lichens is largely unknown. The aim of this study is to find out how epiphytic fruticose and foliose lichens on Scots pine are affected by fire, and to elucidate the relationship between fire intensity and the survival of lichens and later re-colonization. The study was performed at three locations just outside Umeå in Västerbotten that were burned 5-7 years earlier. In all locations there were larger groups of surviving Scots pines with varying amount of fire-damage in the crown, which enabled a reconstruction of fire intensity.

Comparison of bird communities in stands of introduced lodgepole pine and native Scots pine in Sweden

The introduced lodgepole pine (Pinus contorta) occupies more than 650 000 hectares in Sweden. There are some differences between lodgepole pine and Scots pine (Pinus sylvestris) forests which could affect bird assemblages, for example differences in canopy density and ground vegetation. Birds were surveyed in 14 localities in northern Sweden, each characterized by one middle-aged stand of lodgepole pine next to a stand of Scots pine. The two paired stands in each locality were planted by the forestry company SCA at the same time and in similar environment to evaluate the potential of lodgepole pine in Sweden. In those 14 localities, one to three point count stations were established in both the lodgepole pine and the Scots pine stand, depending on the size of the area.

Teknisk och ekonomisk analys av en bränslekonvertering vid SIA TallOils pelletsfabrik :

At SIA TallOil's pellets factory in Latvia wood shavings and saw dust are dried with flue gases from a gas burner. TallOil wants to replace the gas with a biofuel that is available at the pellet plant. The reason for this is the unstable gas market in Europe in combination with the fact that TallOil wants to improve its profile as supplier of renewable bio fuels. In this project the technical and economical possibilities for a fuel conversion to ether bark powder, wood shavings or wood powder have been investigated. These fuels should be burned in one of the following applications: TPS BioSwirl, VTS Multifuel burner or Saxlunds bio fuel combustion plant Due to the fact that the fuel alternatives available are relatively common except for bark powder, the work has mainly been focused on bark powder.

Björkbarksextrakt, BBE : en lönsam lösning på betningsproblematiken?

The calculations in this thesis are evaluating the profit as a consequence from treating young stands of pine in Sweden with birch bark extract, BBE. Treatment is to be done with the object to lower or fully reduce the moose browsing on pine. The study is made in three versions. The results from each version separately will follow below. Version I.: The size of the moose population is in no way affected by the reduced resources of food as a consequence of large scale treatment with BBE on pine. Results show profit at a 3 percent level of interest with the exception of treatment program with more than 4 treatments all together and with the exception of Västerbottens Län with an early first treatment. Version II.: The population of moose decrease from 10 to 5 individuals per 1000 ha as a consequence from large scale treatment with BBE on young pine stands.

Talltimmeraptering - påverkande faktorer

In this work, I describe the factors that affect the bucking of pine logs on the basis of the machine operator. The aim is to find an explanation why the bucking differs so greatly between requested length results and the actual length results in pine bucking. The used methods in this study were data from simulated pine outcomes, data from earlier length outcomes and analysis of the harvesters' PRI files. This is to identify the problem. To explain the background to the problems a qualitative research interview was used.

Contortatallens odlingsvärde i Götaland

The third most common conifer in Sweden is Pinus contorta (lodgepole pine). It originates from the western part of North America and was brought here in the end of the 1920s. The lodgepole pine is today allowed for commercial plantations in central and northern Sweden, excluding high altitude locations. Since 1979 only plantations with scientific purpose are allowed in south-central and south Sweden. This document is focused on how lodgepole pine manage perform compared with Pinus sylvestris (Scots pine) in the southernmost part of Sweden, Götaland. The idea came from the fact that the Swedish government is evaluating a notification from the National Forest Agency that suggests lodgepole pine to be allowed for commercial plantation even in southern Sweden.

Factors affecting bark-stripping by red deer (Cervus elaphus) : the importance of landscape structure and forage availability

Bark-stripping by red deer (Cervus elaphus) cause extensive damage to economically valuable spruce trees (Picea abies) in Swedish forests. The underlying causes for bark-stripping are not fully understood, and the frequency and severity of damage unpredictably differ between regions. In this study, I investigated if landscape structure (e.g. agricultural dominated landscape opposed to forest dominated landscape), forage availability, population density and disturbance (e.g. roads and settlements) affect bark-stripping frequency.

Förändringen av tall- och granbestånden i eklandskapet söder om Linköping, 1927 jämfört med 2013

The aim of the study was to compare how the population of pine (Pinus sylvestris) and spruce (Picea abies) have changed between 1927 and 2013 in the oak landscape south of Linköping. A field study was carried out in 22 two kilometre lines which also had been studied in 1927. In these lines, which where ten meters broad and had a direction from west to east, the pines and spruces were counted, measured and classified by steam diameter. The obtained result was that the basal steam area (m²/ha) had increased for pine (44%) and spruce (57%) between 1927 and 2013. The amount of trees had increased in all diameter classes except thinner pine and spruce with a diameter of 5-10cm.

Urskogen med de stämpelbleckade gammeltallarna : en skogshistorisk tolkning av Brännlidens naturreservat

People have used forest resources in northern Sweden for different purposes. Before the 20th century the forest was used for many different reasons, but during the past 200 years it has become an industrial raw material. The presence of people in the forest has left different kinds of traces in the forests. One example is culturally modified trees (CMT´s). The aim of this study was to study and document how people have used the forest resources during the last centuries in Brännlidens nature reserve, and what kind of traces this land use has left.

Jordlöparfaunan i bestånd av contortatall (Pinus contorta) och svensk tall (P. sylvestris) 1987 och 2010

In the 1970´s the North American lodgepole pine (Pinus contorta) was introduced to Sweden in large scale. The lodgepole pine affects its new environment different from Scots pine (P. sylvestris), leading to a change in biological diversity. Forestry today affects the ground beetle fauna (Carabidae). Habitat specialists associated with older forests are first affected. When the canopy closes again after a clear-cutting species that prefer open habitats reduces and those who prefer mature/closed forests increase. In this study we compare differences in diversity and community structure of ground beetles in stands of lodgepole pine and Scots pine.

Subjektiv och objektiv bedömning av underlag på svenska hopptävlingar på elit- och nationell nivå

Bark-stripping by red deer (Cervus elaphus) cause extensive damage to economically valuable spruce trees (Picea abies) in Swedish forests. The underlying causes for bark-stripping are not fully understood, and the frequency and severity of damage unpredictably differ between regions. In this study, I investigated if landscape structure (e.g. agricultural dominated landscape opposed to forest dominated landscape), forage availability, population density and disturbance (e.g. roads and settlements) affect bark-stripping frequency.

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