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427 Uppsatser om Tree clearance - Sida 1 av 29

Does tree removal along railroads in Sweden influence the risk of train accidents with moose and roe deer?

After the storm Gudrun in 2005, the Swedish Transport Administration started clear-cutting of railroad corridors to reduce the risk of trees falling down on the tracks. Simultaneously, train accidents with moose and roe deer have become more frequent and the costs for consequent delays and repairs of engines are of growing concern. There is reason to assume that tree-clearance of railroad corridors may have contributed to an increase in number of accidents with moose and roe deer because the cleared areas provide attractive forage and thus may attract wildlife. The objective of my study was to investigate how clearing of trees affected the number of accidents with moose and roe deer. I compared deer-train collision frequencies before and after clearance of the selected railroads and compared these with uncleared control railroads in a BACI (before-after control-impact) approach.

Mindre studie av en ny gallringsmetod i stamtät förstagallring av gran i södra Svergie

The main purpose of this study is to investigate how to reduce the high, and every decade raising, pre-clearance cost. The pre-clearance is today carried out with a brush saw and paid per labour hour. All small trees not suitable for pulpwood are removed to simplify the later work of the harvester. The study compares the economic results from thinning of four parcels each treated differently regarding harsh or light pre-clearance and extraction of only pulpwood, or both pulpwood and fuel wood. In this type of spruce stand the study indicates that a lighter pre-clearance, followed up with both pulpwood and a fuel wood extraction, has a much better economy than the traditional method of hard pre-clearance and only pulpwood extraction..

Mark röjd från sten : En studie av förklaringar och tolkningar kring röjningsröseområden

AbstractThis essay discusses different explanations and interpretations of what characterizes large areas containing clearance cairns (cairn fields). Results from the analyses show that there are different explanations about when and why cairn fields and clearance cairns occur. Explanations vary from introduction of the wooden ard in the early Bronze Age to the introduction of rational hay-making in the Roman Iron Age.  There is, anyway, relative agreement considering why and when cairn fields were abandoned. The reason suggested is an increasing pasturage with the consequence of reducing soil to poverty during the period of the Great Migration or in the Viking Age.The most likely cultivation system in cairn fields is a system consisting of both intensive and extensive characteristics. The latter coincides with the probable mobility of settlements.

Diskussion om röjningsrösen : med teorier om gravrösen i fossil åkermark och skärvstenshögar

This paper aims to investigate the connection between clearance cairns and burial cairns. From this point of view I try to answer the questions why they are built in the same area and why these two different types of cairns are so similary constructed. Further I consider different theories about mounds of fire-cracked stones..

Utvärdering av en ny typ av lagerinbyggnad för traktionsmotorer

The thesis evaluates a new kind of bearing arrangement in a traction motor that ABB hasdeveloped. Since the arrangement is designed in a new and innovative way it needs to beevaluated to see if it is safe to use. In today?s traction motors, bearings with a big internalclearance (C4-clearance) are used. The basic idea of the new arrangement is to reduce the fitsbetween the bearing and shaft/house.

Datering av röta i hålekar :

I have chosen in this work to examine which factors are affecting the artificially creation of a tree cavity containing decomposed wood. The purpose of the work is to find out which factors are affecting the most when a tree cavity is created, and to apply these results when you artificially try to create a tree cavity. The need to create tree cavities comes from the situation where many tree cavity living beetles finds themselves today. When existing trees are to pass out there will be no suitable inheritors yet. The work was initially to focus on cavities created from cut branches.

Det enskilda trädet som meningsbärare : erfarenheter av två trädplanteringsprojekt i Helsingborg

Individual trees can act as carriers of meaning. When a person attributes deep meanings to a specific tree, a relationship between the person and the tree is created. To avoid conflicts between users and planners, increased awareness is required of how important individual trees may be to a person. The objective of this study was to elucidate persons? relationships with individual urban trees.

Tee Tree Oil - Ett effektivt behandlingspreparat i tandvården?

Tea Tree Oil eller TTO som det förkortas, är en olja som utvinns ur en australiensisk buske vid det latinska namnet Melaleuca alternifolia. Oljan har sedan många år använts som antiinflammatoriskt och bakteriedödande ämne. Denna litteraturstudie gjordes på 13 artiklar som svarade på tre sökningar i databasen PubMed. Artiklarna påvisar att TTO har en viss antibakteriell förmåga och kan fungera som antimykotiskt medel, men fler in vivo studer behövs för att säkerställa TTO:s effekt på olika parodontala åkommor..

Träd som berör : en intervjustudie om specifika träd i människors liv

There is no doubt about the significance of nature on the health of human beings. Not only is the tree an element of nature that is of great value to our survival, it also serves as a valuable object and symbol of human beings? enjoyment and appreciation of the environment. The purpose of this study is to present the relationship that a person may have with a specific tree. Three women and two men are interviewed about their trees and the places where they are located.

Produktionsskillnader vid olika antal sortiment

This study is done together with Sydved AB in the summer of 2012. The purpose of the study is to analyse how different quantity of assortments influence the production for forwarders and harvesters with multiple tree handling aggregate in thinning, by different tree volumes. To make this analyse a time study was performed where three entrepreneurs work has been analysed. Beside the analyse, of different quantity of assortments, has also been analysed how the tree volume and a forest fuel assortment effect the production. The result of this study shows that the quantities of assortments have a significant meaning for the production. The biggest differences are most distinct between one and three assortments in the smaller tree volumes where production goes down if the quantity of assortments increase.

Jätteträd ? inventering, bevaring, skötsel samt rekrytering :

During the summer of 2007 I was employed by Högestad Christinehofs Förvaltning AB. My main task was to make an inventory of giant trees at the estate. Högestad and Christinehof,which with their total possession of 13 000 ha of land is the biggest estate in Scania. A giant tree is a tree with a diameter in breast height more then 1 meter. Trees of these dimensions are registered by Swedish authorities. Landowners with a giant tree on their property can receive a subsidy for cutting trees that are in competition with the giant tree.(Levenskog, 2007) Giant trees are important for biodiversity in the landscape and there are important habitats for different insects, birds, bats, lichens and funguses.

Hackerör på Sydsvenska höglandet : vad skiljer röjningsröseområden från celtic fields, stensträngsområden och bandparcellområden?

From the pre-Roman and Roman Iron Age, a number of different fossil agrarian landscapes can be found in southern Sweden - clearance cairn areas, celtic fields, stone-wall complexes and geometrically laid-out strip fields. With two different comparative analyses, this paper tries to explain some of the differences between clearance cairn systems and the other fossil field systemsThe shape of the early Iron Age agrarian landscape varies between different provinces of southern Sweden. At Gotland, celtic field systems were laid-out before 500 BC. In Småland at the same time, areas with clearance cairns were created. How can the difference be explained? The different physical appearance of clearance cairn areas and celtic fields can be explained by the different ways to handle the ard in till and in sandy soil.

När trädens rotsystem får bestämma : En intervjustudie med en grupp yrkesverksamma inom anläggning av hållbara gröna miljöer.

ABSTRACTThis pilot study examines the knowledge about tree root systems amongst five treeplanting professionals. The aim is to find out the professionals? collective knowledge ofthe nature of root systems of various trees used in green areas. Furthermore; to explorehow the professionals adapt landscaped green areas to the tree root properties in asustainable manner. Questions: Which tree species have special root properties toconsider and how do the professionals utilize this knowledge? And: How do theprofessionals in general adjust planting according to the root systems of trees in areas tocreate sustainable green environments?Interviews with the professionals were performed.

The shift in forest and tree limits in Troms County - with a main focus on temperature and herbivores

To better understand how various factors affect the establishment of forest and trees around the tree line-ecotone, this study was conducted in Troms County, Norway. The altitude of different forest and tree limits together with the surrounding vegetation type were collected during August 2011. Comparisons of the collected data were made with previously collected data from the same sites conducted 1914 and 1915. On average the forest limit has expanded with 26 meters in altitude, however, an expansion is not statistically significant for the whole area. The tree limit has significantly expanded in altitude.

Dendroklimatologisk analys av lokalklimat vid Grövelsjön i Dalafjällen

Climate on earth is getting warmer, which effects earth?s energy balance and so forth the ocean and atmospheric circulation.  In many sub-polar regions on the northern hemisphere changes due to warming of the climate can be observed. Some examples that already have been observed are shifts in tree line, towards higher altitudes and latitudes, increased ablation of Swedish glaciers and melting of the permafrost on the Siberian tundra. In Sweden climate change scenarios tell us that it will become warmer and that a higher amount of precipitation in form of rain will be an effect from this. To study climate changes in Sweden, transition zones are useful in order to observe changes in distribution of species and animal populations.

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