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79 Uppsatser om Coarse woody debris - Sida 4 av 6

Lilaköttig taggsvamp, Sárcodon fuligíneovioláceus : miljökrav i Sverige och en analys av vad som styr artens etablering

Burnt Spine-cap Sárcodon fuligíneovioláceus are one the most endangered mycorrhizal fungal species in Europe. They have their main distribution in Sweden. It form mycorrhiza with pine and dependent on limestone, which makes it connected to a rare environment. It has therefore been important to study the ecology of it further and to recognise the requirement it has on the environment more accurate and what it need to establish in a new area. In this study, 31 of 34 known sites in Sweden was visited and studied in field and their history analysed through aerial photographs.

Häckar för Norrland

I have observed that hedges are not as prevalent in gardens in the north of Sweden as in the south despite a number of beneficial qualities attached to their use. Consequently, the primary purpose of this essay is to examine the potential for the use of ligneous or woody plants as hedges in a cold climate. The aim of this study is to provide information about the various varieties of ligneous plants that can be used for both pruned and unclipped hedges in the north of Sweden. Because the hardiness of the ligneous plants is a vital factor here, only plants that are hardy enough to survive in the Swedish hardiness zones V to VIII are included in this study. Roses, dwarf shrubs, conifers, bushes with a final height of less than 1 metre and plants that ?bleed? have been excluded.

Varför svänger stenen? : En studie i curlingens komplexa tribosystem

The tribo system ice-curling stone was investigated in order to understand the mechanisms behind the stones' behavior on the ice sheet. The problem with non-identical stones should also be addressed.The stone curls, that is, its sliding path deviates from a straight line to the right for a clock-wise rotation and to the left for a anti-clock-wise rotation. Several mechanisms to explain this behavior have been proposed over the years but none has been successful.By carrying out experiments at the local curling rink and studying silicon castings of ice- and stone-surfaces with scanning electron microscopy and vertical scanning interferometry, it has been decided that the curl is not due to dry friction, ice-debris or the difference in friction on the left and right side of the stone. The side force comes from the fact that the friction is higher at the back of the stone than at the front.The contact between stone and ice is never completely dry, nor in the hydrodynamic lubrication regime. It is probably a combination of hydrodynamic lubrication and a contribution from mechanical scratching of the ice.

Miljöpartiet - ett parti i förändring : En komparativ textanalys av Miljöpartietspartiprogram mellan 1994 och 2005

Following changes in society and other influences, the ideology of political parties can evolveover time. For example, theories exist claiming that all parties in Sweden strive towards the"middle".A good example of a political party in Sweden which recently has gained entry toparliament is the Swedish Green Party (Miljöpartiet, MP).MP was initially influenced by a green ideology (ecologism) which started as a globalmovement stating that no other ideologies shared their concerns about the environment. Thegoal of the ideology was to, via an increased influence within the political system and throughsmall-scale production, increases both natural values and people's well being. By becomingelected into parliament it is plausible that the ideology of MP could have changed due to theinfluence of for example, the realities that parliamentary every day represent.The aim with this essay was to study the changes in MP's party program from the yearof 1994 and the most recent, to see if any changes have occurred related to MP's officialideology. The study was conducted using a comparative text analysis.

Skydd mot yterosion i slänter av finmorän

Slopes in fine till soils are exposed to surface erosion due to rainfall, snowmelt and upland water sources. Large areas of road slopes are therefore covered for surface erosion protection. Preventive methods like ditches and trenches are also being used. Silt tills are particularly troublesome since the water can bring the soil into suspension and cause mudslides. Different methods for erosion protection have been studied in this work, with the emphasis placed on rockfill covering. The need for and the dimensioning of this type of covering has been examined in literature and field studies.

pH-sensitivity in boreal streams ? the influence of landscape characteristics

The goal of the society to increase the proportion of renewable energy has led to an increased demand of bioenergy e.g. forest biomass. However, there are concerns that removal of biomass will lead to decreased base cation concentrations in the soils and acidification of streams. In order to find in which types of landscape removal of branches and tops could have such negative effects, this study aims to analyse the relations between pH-sensitivity and landscape variables in the Bothnia Bay water district. GIS and digital geographical data were used to analyse the landscape in subcatchments.

Framtagning av normalt referensintervall för RDW och retikulocyter på hematologiinstrumentet ADVIA 2120

Erythropoiesis is a complex and carefully controlled process which is mainly regulated by erythropoietin. Using flow cytometry cells in a blood sample can be analyzed one by one. ADVIA 2120 using flow cytometry for analysis of red blood cells (RBC) and reticulocytes. Red blood cell distribution width (RDW) is a component of the RBC method. RDW indicates size variation on erythrocytes and is measured as a percentage of the mean cell volume (MCV). By measuring the RDW anemia can be divided into makrocytic, microcytic or normocytic. Reticulocytes refract light more strongly than red blood cells because they contain some cellular debris. The number of reticulocytes in the peripheral blood reflects erythropoiesis in the bone marrow. The purpose of this project was that by approved methods to establish reference ranges for the parameters, RDW and reticulocyte counts.The individuals who participated in the study, n=124, were considered healthy and had varying ethnicity. Reference subjects had not donated blood the last six months and participation in the study was voluntary.The statistic evaluation includes examination of distribution, and reference ranges for both men and women were established using the 2.5:t and 97.5:t percentiles. The calculated reference interval for RDW was between 12.0 ? 14.3% and the calculated reference interval for reticulocytes was between 38.0 ? 112.8 x109 cells/L. The results showed a significant difference between males and females for the parameter reticulocytes was seen. The difference indicates that different reference ranges should be established for men and women (p<0,0001). No significant difference between males and females were seen for RDW (p=0,74) indicating that the same reference ranges can be used for both men and women. .

Lokala skillnader i konsumtion av påväxtalger och terrestra löv hos en differentierad population av Asellus aquaticus

That ecological and evolutionary processes can take place on the same time scale is a recent insight. Today we also know that they are directly linked to each other. In the lake Tåkern, in year 2000, there was a structural change when phytoplankton declined and submerged vegetation, mainly stoneworts began to spread. This led to evolutionary changes in the aquatic sowbug, Asellus aquaticus which had previously been limited to the reed, most likely feeding on detritus. But then, sowbugs could exploit the new habitat in stoneworts and a new food resource in terms of periphyton.

Naturvårdande skötsel (NS) - blir resultatet som man tänkt sig? : en fältstudie över föryngring, trädslagsfördelning och död ved 14 år efter åtgärd

A new Swedish political approach to forestry was initiated 1993, that put goals of production and environmental issues into equal importance to Swedish Forestry Law. Earlier nature conservation very often declaimed preservation the best way to conserve nature, but recently it is clear that many highly biological values are due to former land use or disturbance. Many old pastures or cultivations dominated by deciduous trees are today characterized by a dense overgrowth of Norway spruce. By actively paying attention to nature in forestry (nature restoration), it is possible to partly reconstruct habitats or disturbances that are necessary to favour the biological values. The aim with this master thesis is to study the nature restoration, (NS, Swedish abbreviation), performed in 11 forest sites in the middle of Sweden 8-14 years ago. Since NS recently have become applied, it has never yet been evaluated.

Composition of fractions from air-classified wheat flour

The unique ability of wheat to produce leavened bread is mainly due to the gluten proteins present. As consumers are more and more attracted to bread with high fibre content the use of wheat gluten will also increase in order to obtain bread with good volume and appetizing characteristics. Air-classification is a technological method used to separate particles by size and shape by means of air-streams into two fractions, fine and coarse. When used on wheat flour it is known to alter the flour composition in the fractions obtained compared to the original flour. This method is not widely used in the milling industry but could possibly be of interest if protein rich fractions with favorable protein quality can be produced.

Stubbtransporter - en jämförelse av tre olika transportsystem

In Sweden, the demand for bio energy has increased in recent years due to the current energy and climate debate. In 2008, the energy supply of Sweden was 612 TWh, biofuels accounted for 123 TWh of these. Stumps have been highlighted as a potential fuel in recent years and the Swedish Forest Agency expects a technically and biologically feasible potential of 20.7 TWh annually between 2010 and 2019. The idea of utilize stumps is not new. During the 19th century stumps were used for tar production and during the 70?s and 80?s attempts were made to use stumps in the pulp industry.

Kommuninvånarnas syn på Sala kommuns skogar och skogsbruk

The municipal forests of Sala cover an area of 6 000 hectares, starting in the vicinity of the city and reaching north. At the same time as residents make abundant use of the areas closest to the community for outdoor activities and recreational purposes, the forest is of great economic value and also worth protecting for environmental reasons. These conditions make forestry in periurban woods more complex than conventional forestry, why a good understanding of the needs and demands on the forest and silviculture program is required. The purpose of this study is to depict the usage of the forests owned by the municipality of Sala, to set forth the common view of the silviculture program implemented by the municipality and to chart the expectations the community has on the forests and forestry of the future in the municipality of Sala. The survey part of this paper consists of the interviews of thirteen individuals representing nine interest groups. As expected the views of these individuals varied widely but some results were expressed by more or less all of them.

Från periferi till piedestal

AbstractThis paper is a study in press reception with the intent to examine how twelve female actionheroes have been portrayed in Swedish media between 1974 ? 2006. The purpose is to discern patterns and differences in how the female movie character is received by their contemporary journalists and to relate their views to social and gender related theories. The female actionhero is an independent and brutal character, often alone and without a mother or a child. This separates her from typical female roles, which historically been characterized by passivity, fear and dependency on the male characters in the movie. The female actionhero as a character opens up for complex reception. One perspective in the research identifies the independent woman as a feministic icon.

Analys av turbulensmodeller för CFD

This thesis has been a part of Forsmarks Kraftgrupp AB's evaluation of a turbulencemodel used in simulation of turbulent flow called PRNS (Partially Resolved NumericalSimulation). This model has promising properties and may be of use in savingcomputational resources. The purpose of this thesis was to analyze this model andcompare it with industrially applied models such as k-omega SST and LES (Large EddySimulations).PRNS works as a hybrid of the k-omega SST and DNS (Direct Numerical Simulation)where a constant, RCP (Resolution Control Parameter) with a value between 0 and 1are selected. This constant is then used in the calculations and determines thebehavior of the simulation. When RCP is set to zero the equation are the same as fora DNS simulation and when RCP is set to one the equations for k-omega SST issolved.

Tickor på död ved

I dag råder det brist på död ved i Sveriges skogar. Detta på grund av det intensiva skogsbruket där man kalhugger och plockar bort all liggande ved. Dock är det viktigt med många döda träd i olika nedbrytningsstadier för många skogslevande arter. Svenska skogar har få urskogar där naturliga avdödningsprocesser av träd får ske och därför minskar den biologiska mångfalden i skogen. Tre arter som endast trivs i naturskog är tickorna ullticka, Phellinus ferrugineofuscus, gränsticka, Phellinus nigrolimitatus och vedticka, Phellinus viticola.

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