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841 Uppsatser om Multi-tree harvesting - Sida 5 av 57

Beståndsutveckling i stormskadade granbestånd

The storm Gudrun in 2005 led to massive windthow damage in forests in southern Sweden. Since then there has been a growing interest in factors influencing wind damage in above all Norway spruce (Picea Abies) stands. Although many other interesting areas still need to be examined. In 2005 there where a lot of stands that suffered different degrees of damage, a lot of these stands weren?t cut, but instead left to grow. The future development of these stands is uncertain and the guidelines are unclear.

Skötselåtgärder vid nyetablering av skyddszoner vid bäckar i södra Värmland :

Buffer zones play an important role for the water quality in our watercourses. When harvesting a forest close to a watercourse a buffer zone should be left. When it's not left, it will lead to radical changes in the environment for the water organisms. The overall purpose of this thesis was to illuminate the production- and environmental thinking when establishing new buffer zones in south of Värmland. The partials goals were to determine choice of tree species, ways of regenerate, occurrence of soil scarification and the occurrence of machine tracks in newly established buffer zones.

Base stations for communication in obstructed environments

The purpose of this project was to produce signal relay stations that could receive information via 2.4 GHz radio and relay the information to a designated target station. If a relay station was located outside of signal range for the target station it was supposed to utilize other relay stations to transfer the information to the target station, so called multi-hop.The would-be application of the relay stations was orienteering. When an orienteer punches a checkpoint the signal stations would relay information of who punched the control, when it was punched and the checkpoint that was punched to the speaker tower in the goal area.The work resulted in prototypes which fulfilled the statement of purpose and was tested at an orienteering competition with satisfactory results. The performance of the prototypes was tested and found adequate for the would-be application..

Laserdata i skogsbruket : - och möjliga tillämpningar för privata skogsägare

Data retrieved from airborne laser scanning represents a new source of forest data. Today, the technology has matured so that it can function in an operational environment. The aim of this study was to compile areas of application of laserdata in forestry. Moreover to analyze costs and accessibility of laserdata. The goal was to provide private forest owners information to support assessments of possible benefits of laserdata.

En lärarutbildning för en mångsidig värld : En historisk genomgång av den interkulturella lärarutbildningen på Södertörns Högskola

The aim of this essay is to describe the historical development of the intercultural teacher training program at Södertörn University in Stockholm. I have also examined how the intercultural teacher training program was started, how and why it became intercultural and how the people in charge of the development of the teacher training program discussed intercultural science. The teacher training program has been an active part of Södertörn University since 1998, but it became intercultural in 2002. I have studied these questions through documents from the Södertörn University archives and literature by the funders of the education. The study shows that the university profile, ambitions and motives have been a key factor in the decision to make the teacher training program at Södertörn a multi-cultural one..

Examination of mycorrhizal associations of Allanblackia stuhlmannii : a tree under current domestication

Allanblackia is a tree genus native to humid forests in West, Central and East Africa. Its fruits contain large seeds from which edible high-quality fat can be extracted. In order to create a sustainable supply chain of Allanblackia seeds, a domestication program has been initiated with the purpose to enable smallholder farmers to grow the tree as an agroforestry component and cash crop. More knowledge is required to understand the tree?s biology and possible symbioses involving soil microorganisms with plant growth enhancing poten-tial.

Hyggesbränning på Orsa besparingsskog - en studie på tillväxt och föryngring,15år efter etablering

The main purpose with this study was to investigate whether the tree growth differs or not in prescribed burnt areas compared to mechanically scarified. Together with the result from the main purpose, answers of whether it's possible or not to combine nature conservation with tree production in prescribed burnt areas was presented. In these areas the regeneration were analyzed to see if there was enough tree plants to comply with the Swedish Forestry Act regulations terms for approved regeneration. A field survey was conducted at 6 objects, three objects for prescribed burning and three for mechanically scarification. All objects were planted within the same year.

Provtagning av trädkärnor för att bedöma föroreningsgraden av klorerade lösningsmedel i grundvatten

Chlorinated aliphatic hydrocarbons (CAH´s) were used widely within dry cleaning facilities and for metal degreasing until their toxicity was discovered. PCE is still used as dry cleaning liquid. Today CAH´s are found in soil environment at places where they have been used in the past. The CAH-concentration in trees growing on contaminated land has quite recently received attention as a cheap and effective way of assessing the extent of a CAH-contamination. The method has however, not been put into use in Sweden.The aim of the study has been to investigate whether the CAH-concentration in tree cores could be used to delineate the spread of CAH in a soil environment under Swedish conditions in different seasons.

Tree species traits response to different canopy cover for 34 tree species in an enrichment planted tropical secondary rain forest in Sabah, Malaysia

Tropical rain forests only cover around six percent of the world?s land area and contain around 70 % of the world´s animals and plants. Tropical rainforests have been, and still are, negatively affected by human activities. These activities lead to forest degradation which has negative impacts on production and biodiversity. Between 1970-1980 forests in Borneo, Sabah, Malaysia, was subjected to intense logging.

Vindfällning i naturliga och skapade bryn och kanter :

The aim of this work was to study if the edge of the forest is more resistant to heavy winds than the trees located further in from the edge, and how this edge effect changes between different types of tree species and site types. The data was collected from an electric power line going from the north to the south of Sweden. The mean value of the clearcutted area around the power line was 120 meters. The main direction of the storm in January 2005 was west-southwest and thus the power line was a perfect place for gathering a large data set. The main parameter studied was the damage frequency at the edge of the forest compared to the trees located further in from the edge (up to 100 m from the power line). Tree species mixture, soil moisture class, soil type, topography, stand height, stand height of the stand on the other side of the power line and wind exposition was estimated. The results showed a distinct edge effect. The edge of the forest had clearly lower damage frequency for all tree species. A marked difference was observed between tree species and damage frequency.

Skogstillväxten ca 20 år efter plantering på Flakmossen : dikningens och gödslingens betydelse vid beskogning på en avslutad torvtäkt i Värmland

This study was performed in an afforestation experiment established 1982 on an abandoned peat harvesting area, Flakmossen, in the province of Värmland, SW Sweden. The experimen-tal design include planting with Scots pine (Pinus sylvestris), in combination with various drainage intensities (20, 30, and 40 m between ditches), and fertilizer doses 0, 100, and 200 g PK per seedling applied at the date of planting. The aim of this study was to achieve more knowledge about the conditions on afforestation of peat harvesting areas, especially regarding drainage intensity and fertilization requirements, by means of determining the stand growth and yield in the Flakmossen trial. The forest growth did not differ significantly between the drainage intensities tested when the same amount of phosphor and potassium fertilizer was added. Thus, shorter distances between ditches than 40 m can not be recommended. When no fertilization was carried out seedling survival was very low, and the growth of sur-vived seedlings was poor. The largest diameter and height growth were observed in the areas where the highest dose of phosphorus and potassium (200g/seedling) was given.

Formella förändringar i svensk sysselsättningspolitik : - En kvantitativ innehållsanalys av samvariationen mellan svensk sysselsättningspolitik och EU:s sysselsättningsstrategi

The intention of this study is to perform a content analysis based on a theoretical framework founded on multi-level governance, MLG. The thesis examines the formal changes within employment politics between 1999 and 2004 (Sweden´s action plan for employment) and 1998 and 2007 (the spring budget proposition). I will investigate how multi-level governance has effected the Swedish employment politics. Furthermore, the purpose of the thesis and the questions under consideration are: How have the formal structures within Swedish employment politics changed since Sweden?s admission to the European union, particularly during the periods 1997-2008 and 1999-2004? And: How do the changes in Sweden, together with the European union directive concerning employment, coincide in the so-called employment strategy?While performing the analysis I have focused on multi-level governance.

Application development for touch-screen interfaces

The way we interact with computers will soon change dramatically. The input interfaces are becoming more and more intuitive and one of the latest technologies is a touch screen interface capable of dealing with multiple inputs simultaneously. The tools we use to communicate with the computer - such as the mouse and the keyboard, will slowly disappear and be replaced with tools more comfortable and more natural for the human being to use. The purpose of this project was to create a basic framework for future projects dealing with this interface, as well as creating some example programs. This report describes my work and my experiences with this new interface..

Askgödsling och dess lämplighet i torvmarksskogar tillhörande Sveaskog Förvaltnings AB : en litteraturstudie

During whole-tree harvesting, there is a risk that the soil will become impoverished of nutrients. To prevent this, nutrients are returned to the harvested site as wood ash. This action also reduces the risk of soil acidification. Nevertheless, the ash does not result in any increase of tree growth if it is added on mineral soils, which is where the measure is most commonly used in Sweden. Due to the lack of growth response, the interest from landowners is small, which is why ash amendment today is not done enough to compensate for the need.

Lokaliseringsutredning för nytt hotell i Sandvikens tätort med stöd av multikriterieanalys

The municipality of Sandviken is in a state of strong growth. This affects the need for more hotel rooms in Sandviken, in a way that it?s profitable to invest in a new hotel. Sandvikens largest company, the steal industry Sandvik AB, grows just like Sandviken, and have great influence on the need of more hotel rooms. Today there are three hotels placed in Sandviken, and these hotels aren?t enough when the pressure of hotel guests is at its top.The purpose with the project was to analyse the criteria?s that are important for localization of a new hotel in the Sandviken, and to clarify what kind of hotel Sandviken is in need of.

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