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355 Uppsatser om Trees - Sida 8 av 24

Effekterna av urbanisering, barksprickedjup och solexponering på lavfloran i sydöstra Sverige

Studies have shown that air pollution, as well as bark fissure depth and sun exposure of a tree can have an effect on lichen growth as well as abundance of lichen species. The aim of this study was to find out the relative importance of these factors. 211 oaks in south eastern Sweden were surveyed for presence of 17 lichen species, as well as the total number of lichen species. Half of the Trees were situated in urban areas and half in the countryside. For each tree the bark fissure depth was measured and the sun exposure of the trunk was estimated.

Hur en ökad marktemperatur påverkar fotosyntes och markrespiration i en boreal skog

During the year of 2008, a powerful earthquake hit the southern part of Iceland, which changed the geothermal conditions in the area around the city of Hveragerdi. Elevated soil temperatures in a nearby forest plantation have contributed to a unique opportunity for researchers to study how an increased soil temperature affects the boreal forest ecosystem, something that partly can be connected to the climate changes which are happening today. The boreal forest is representing a carbon sink and a buffert for the emissions that occurs. Changes in this ecosystem will for that reason contribute to major impact for the global carbon cycle. To study the impact of how elevated soil temperatures affects different processes in a plantation of Sitka spruce, studies were made on the photosynthesis of the Trees and the respiration from the soil.

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.

Skolträdgården i folkskolans miljö på Gotland : med exempel från Bunge- och Stenkumla skola

The thesis explores the phenomena of historic school gardens connected to elementary schools on Gotland, Sweden. Gotland had the highest percentage of school gardens connected to the elementary schools in Sweden, and by investigating this area much can be learned about the Swedish conditions. The study focus on the period in time when the school gardens were most frequent and used the most, to the point in time when they start losing ground. To bridge over the past to the present the thesis also investigates what is left and play with the thought of possible ways to treat the remains. The main question for the thesis is: How could a school garden on Gotland be constructed and be used 1907 ? 1947?And a follow up question is: What could still be there today and how can/should the remains be treated and conserved? The thesis begin with an overview look at the school gardens of Sweden, closes in with on Gotland and completes with a deeper investigation of two examples of school gardens; Bunge and Stenkumla elementary schools.

Kastanjemalen Cameraria ohridella : livscykel och utbredning i Sverige 2006

Cameraria ohridella, the chest-nut leaf miner, is a new pest in Sweden. These moths make leaf mines on chest-nut Trees, preferably on Aesculus hippocastanum, which results in brown blotches on the foliage and early loss of leaves. Since the first observation in Macedonia in 1985 it has spread rapidly through Europe. The moth arrived in Sweden in 2003 when it was observed in Malmö and surrounding areas. In this paper a literature study describes the morphology and life cycle of the chest-nut leaf miner. Further more a test with pheromone traps examining the number of generations in Sweden is shown.

Produktivitet och lönsamhet vid skörd av skogsbränsle i klen björkgallring :

The aim of the study was to compare productivity in first thinning of birch stands, when either energy- or pulpwood was harvested. The systems total profitability was also compared by including forwarding and chipping costs. A Gremo 950 HPVR harvester was used and the same driver was used under the entire study. During the pulpwood harvest a Logmax 4000b harvester head was used and a feller buncher head made by Silvatec was used during the energy wood harvest. Six study unit pairs were located in a birch dominated stand outside Ängelholm in Skåne.

Metod för kartläggning av lövråvara i Södra Skogs verksamhetsområde

Södra Skog chose in 2011 to convert the saw mill in Traryd to a gradually refined sawmill of hardwood. In 2009, they had also acquired the hardwood sawmill in Djursdala. This was strategically important for Södra's business since the demand for hardwood products has increased. The standing volume of deciduous Trees in Sweden is today approximately 524 million m3sk and it has increased rapidly in recent years. However, the deciduous forests are to a large extent located in areas that are set aside for nature conservation and is thus not available to the industry.The goal of this work is to create a simple and reliable method for mapping of deciduous wood volumes in areas where Södra Skog is operating (Götaland excluding Gotland).The material that is used is raster databases with estimated forest attributes (kNN-Sweden), data from National Forest Inventory (NFI) and forest management plans.

Att restaurera forna tiders beståndsstruktur : ett exempel från Jämtgaveln

In Sweden today so-called "prescribed nature conservation burning" is performed due to the change in silvicultural law, certification and an increased knowledge regarding the field of fire in the forest landscape. The aim is to re-create structures and qualities made by the fire regimes of the past, though on a much smaller geographical scale. The structures and qualities to be re-created are for example broad leaf stands, Trees with large diameter, heterogeneous stands regarding variables such as age and diameter. If we increase our knowledge of the constitution of forests characterized by fire, then we will be able to set goals for what achievements to reach both on landscape scale and stand scale. The aim of this paper is to try to describe how a stand from the past was composed regarding mainly the spatial arrangement and compare it with the stand of today in the same place. This to be done by using relict material, that is stumps and dead standing Trees.

Mångbruksplan inriktning vilt och viltvårdsanpassning av skogen

This multiple use forestry plan is made on the property Basunda which is located in the southern parts of the province Östergötland. The owners of the property today are Jonas and Ulrik Saanum, but it has been in the family since their grandfather bought it 1933. There is a slaughterhouse on the property in which they take care of domestic cattle and animals from the forest. Jonas and Ulrik are also dedicated hunters. These are the two reasons to why the focus is wildlife and wildlife management. The question at issue of this work is simplified: what demands does the wildlife have; and how will the owners be able to fulfill these, what changes in the forest management must be made and will these changes result in a different budget, compared to the ordinary forest management. This work is based from a freshly made forestry management plan. I based my fieldwork on this plan, but made my own management proposals, that would benefit the game.

Klövviltets nyttjande av foderraps på viltåker och betespåverkan på angränsande skog

Today we have more game species than ever before in our landscape, both regarding number of species and number of individuals. The increasing number of wild species is an increase in game recourse for the countryside. The increase of game species, however, has negative effects on forests and agriculture land. The negative effects for forestry are damages on economic important Trees, due to losses in production and quality. However there are ways to decrease the damage on valuable and important Trees.

Potentiella arealer för ökad virkesproduktion i norra Sverige genom skogsodling med Pinus contorta var. latifolia, Larix sukaczewii, Abies lasiocarpa, Populus × wettsteinii och Picea mariana

Sweden is a country with few native tree species. According to Govt. 2007/08: 108, exotic tree species may be seen as an opportunity to increase the growth of tree volume in Sweden. Potential areas where explored In this work for cultivation with Pinus contorta var. latifolia Engelm., Larix sukaczewii Dylis, Abies lasiocarpa (Hook.) Nutt., Populus × wettsteinii Hämet-Ahti (tremula x tremuloides) and Picea mariana (Mill.) Britton et.al.

Artrikedom av kärlväxter i övergivna och restaurerade hagmarker : betydelsen av igenväxningsgrad och tid sedan igenväxning började

Continuously grazed grasslands have remarkably high plant species diversity. In Sweden this type of habitat has declined for the last two centuries. Changed land use has caused habitat fragmentation and loss of habitat quality. This has caused a great number of plant species to end up on the verge of extinction. To try to save this unique habitat and the species that are tied to it, lots of resources are laid on restoration of abandoned grasslands. In this study, plant species richness of continuously grazed, abandoned and restored grasslands were related to degree of overgrowth, time since overgrowth started and rate of overgrowth.

Underhållsarbete på krafttransformator : En studie på genomförande av underhållsarbete i transformatoranläggningen med optimeringsförslag.

This report is the result of a project in the course Independent Projekt in Molecular Biotechnology at Uppsala University during the spring of 2014. The foremost purpose of the course is to give students the opportunity to carry through exstensive work in a project environment. This project was formed based on a comission from the biotechnology company SweTree Technologies, and the goal has been to compose a summary of the different techniques and methods that exist in the field of mass propagation of Trees through the method of somatic embryogenesis.The project group has obtained information about the area mainly throgh reading patents, trying to find key components and bottlenecks in other companies? somatic embryogenesis technologies. This paper is divided into different sections, containing the patents of the automation of different steps in the process.

Vindskador vid stickväg i 1:a och 2:a gallring i Boxholm, Östergötland : i stormen Pers fotspår

Wind damages next to strip roads in 1st and 2nd thinning in Boxholm, Östergötland Anneli Fransson, SLU, inst f sydsvensk skogsvetenskap, Examensarbete no 108 Wind damage is something we are all familiar with since the storms Gudrun (2005) and Per (2007). Research about strip roads and wind damage is very limited. It is commonly known that the Trees next to the strip roads more often fall whit heavy winds, and the purpose of this thesis was to verify this statement. Data was collected from first- and second thinnings at Boxholms Skogar AB, Östergötland. In first thinnings data was collected from both spruce and pine stands and second thinnings only data from spruce stands was collected.

Identifiering av lek- och övervintringsområden för lax (Salmo salar) och öring (Salmo trutta) i Klarälven

Old hollow Trees of oak contain a large amount of wood mould. Unfortunately, these Trees have in the last century been greatly reduced in numbers. It has resulted in that species that depend on these habitats, saproxylic species, have become at risk to decrease in numbers or die out regionally. Previous studies have shown that the volume of wood mould is an important factor for occurrence and population size of saproxylic organisms. The aim of the present study was to examine how the volume of wood mould varies among ash (Fraxinus excelsior), lime (Tilia sp.), maple (Acer platanoides), aspen (Populus tremula) and oak (Quercus robur).

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