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905 Uppsatser om Forest edges - Sida 27 av 61
Karaktärisering av Gremmeniella-skadade bestånd inom Holmen Skog AB :
Since the end of the eighteenth century forest damage caused by the pathogen Gremmeniella abietina has been observed and documented. During the latest epidemic in Sweden more than 480 000 hectares forest land have been injured and this has lead to considerable economic losses. For the pathogen to succeed with infection, spore dispersal and colonization the right environmental conditions is required. The aim of this paper is to describe the diseased stands using site and stand characteristics and to evaluate the effect of these variables on the disease incidence. Further, the thinning performed during the time for spore dispersal and its relationship to injured stands is examined.
Virkesproduktionen under 80 år i ett fältförsök i Dalarna med olika skogsskötselsystem
I Sverige är trakthyggesbruk med kalhuggning det dominerande skötselsystemetmen intresset för kalhyggesfritt skogsbruk har ökat de senaste åren. Alternativentill kalavverkning är omdiskuterade och kritiseras ofta för att inte vara lönsamma.Målet med detta examensarbete är att analysera ett långtidsförsök med olikaskogsskötselsystem och att diskutera eventuella produktionsskillnader. De fem skötselåtgärdersom undersöktes var 1) kalavverkning med plantering av gran och tall,2) naturlig föryngring under fröträd, 3) blädningsbruk, 4) dimensionsavverkningoch 5) orörd skog (referensyta). Fältförsöket ligger på Siljansfors försökspark iDalarna och anlades 1923. Alla försöksytor har en areal av 1 ha.
Visualisering ? ett verktyg för att illustrera långsiktiga konsekvenser av slutavverkning och naturhänsyn
Forestry in Sweden is currently conducted in a manner aiming at equating the production objectives and the biodiversity. To ensure that biodiversity is maintained, patches that are considered to be valuable now or in the future is saved in final fellings. How the tree retention areas will grow into the future forest stands is yet unknown.The purpose of this study was to visualize how different scenarios of natural consideration taken at final felling will evolve in a long term perspective, for two rotation periods. Projections of the forest conditions were executed with the decision support system Heureka and its applications PlanStart and PlanWise. The information about the projected forests was then used for the visualizations which were created in the software Visual Nature Studio.
Till synes orörd skog : naturvärden och kulturhistoria i Rekdalen under 400 år
Nature conservation has for a long time been founded on the assumption that high ecological values depend on low human impact. In Sweden this has led to forests with these characteristics being strictly protected from human influences. However, it is also known that historical land-use can enhance ecological values in forests. Mountainous forests in Sweden, which have not been affected by modern forestry, have for a long time been considered as untouched by people. However, forest history research has in recent years shown that even these areas have been used by people for a long period of time.
Contortatallens roll för virkesförsörjningen på Holmen Skog, Region Iggesund : konsekvensanalys av fyra hushållningsstrategier för contortatall
Large areas of Lodgepole pine (Pinus contorta var. latifolia) were planted in the 1970s - and '80s. The purpose of the fast-growing species was to increase growth and with short rotation periods allow a rapidly increased harvest level. Today a large proportion of the young forests owned by Holmen Skog, Iggesund are covered by Lodgepole pine and an active forest management is required to spread the harvested volume over time which is desirable by a market perspective. The purpose of this essay is to investigate the possibility of spreading the harvested volume of Lodgepole pine over time.
Koldioxidlagring - realitet eller utopi? : En komparativ fallstudie med syfte att undersöka potentialen för koldioxidlagring i geologiska formationer och biologiska sänkor och dess förmåga att bidra till hållbar utveckling
To curb greenhouse gases and mitigate climate change is one of the biggest challenges human society face today. Carbon dioxide (CO2) has accumulated rapidly in the atmosphere as a consequence of burning of fossil fuels and deforestation. The aim of this study is to explore two methods to store carbon dioxide in geological formations and biological sinks. The aim is also to discuss the two mitigation options from a sustainable perspective and whether it can lead to a better environment and benefits for local and global societies. The research questions are: Which method to store carbon dioxide, geological or biological, is the most effective? Which method to store carbon dioxide, geological or biological, has the greatest potential to promote sustainable development for local communities?The method used is a comparative case study and presents four case studies that explore the potential for CO2 storage offshore in Norway and Brazil; and in tropical forests in Mexico and Brazil.
Effekten på nedbrytningen av rötter vid tillförsel av ammonium sulfat i en granskog i sydvästra Sverige
Decomposition of organic matter is a critical process in the ecosystem, which involves many essential biotic and physical parts. Decomposition is therefore an important process both above and below ground. The rate of decomposition is dependent of many environmental factors for example: pH, moisture and supply of oxygen. The decomposition can therefore be affected by large scaled environmental influences, such as acidification and climatic changes. The root litter in the forest is in different ways affected by acidification, liming and manuering.
Strategisk management för privata skogsägare : En metod för proaktiv skogsförvaltning efter stormarna Gudrun och Per.
Familjeskogsbruket har sällan någon anledning att bekymra sig om grundläggande förändringar av verksamhetens inriktning.I ett slag har dock situationen förändrats för skogsägarna i de stormdrabbade områdena. Den uppkomna situationen gör att många olika beslut måste tas som kommer att forma skogsfastigheten i flera decennier. Det finns därför ett behov av att kunna styra skogsgårdens verksamhet så att varje enskilt beslut bildar ett enhetligt mönster mot ett gemensamt mål. Ett sätt att göra det på är att använda teorierna kring strategisk management och applicera dessa på familjeskogsbruken.Denna rapport har utgått från gängse metodik vid strategiframtagning och målsättningsarbete. Olika metoder och verktyg beskrivs till sitt innehåll och syfte.
Skötsel av älgskadade bestånd :
Sweden has today the highest moose (Alces alces) population in the world. The population has been very high since the late seventies and in the beginning of the eighties there was a big ?moose explosion?. The main food source for moose during the winter is young pine (Pinus sylvestris) and birch (Betula spp.). The high moose population has therefore lead to high damage on pine forests over big areas.
Skötsel av torvmarksskogar - vad vet egentligen Västerbottens skogsbolag?
About a quarter of the Swedish land area is covered with shallow or thick peat. There is a potential to increase forest production in Sweden with almost 2 million m3/year in selected peatlands with low conservation values. This increase can be accomplished by drainage, complementary drainage, ditch maintenance operations and fertilization. The purpose of this study was to determine the level of knowledge regarding the management of forests on peatlands and was restricted to selected forest companies in Västerbotten County, with offices in Umeå. Three companies were chosen, SCA, Holmen and Norra Skogsägarna.
Förslag till skötselplan för Uppsala högar och Tunåsen : ett exempel på medbestämmande planering
This Master thesis is made at the request of the local municipality of Uppsala in Sweden. The purpose of this work is to create a guiding management plan. Recreation, conservation of the cultivated landscape and the historical environment, conservation biology and the aim of the landowners are all considerd. The area is almost 34 hectares and located north of the centre of Uppsala. Landowners are the National Heritage Board, the diocese of Uppsala, the university of Uppsala, the local municipality of Uppsala and one private landowner.
Attacks on humans in Sweden by bear, wolf, lynx, wolverine, moose and wild boar in relation to Swedes? fear for these animals
It is not easy to understand people?s fears since they are not always a logical reflection of the danger in certain situations. This study is an attempt to give a scientific view of the potential danger that certain animals in Sweden pose and compare this to Swedes? fear of these animals. A report shows that Swedes? have a certain amount of fear for being attacked by a wild animal in the forest and this fear has increased for certain animals over the last years.
If I had a voice I'd sing: the relation between the forest and the identity in music videos by Fever ray and Iamamiwhoami
Syftet med uppsatsen är att undersöka hur skogen kan användas för att gestalta en bild av
identiteten. För att göra det analyseras musikvideor av Fever Ray och Iamamiwhoami.
Gestaltningen består av två noveller. I dessa undersöks relationen till skogen på ett
mer individuellt plan. Metoden är mer sökande än teoretiserande. Uppsatsen analyserar
musikvideor ur ett genusperspektiv, som bilder och metaforer.
Autumn water sources for understory vegetation and fungi in a boreal forest : an evaluation using stable isotopes
Understory vegetation and fungi are regarded as important ecological drivers of processes like productivity and nutrient cycling in boreal forests. Whilst those processes are linked to soil water content, relatively little is known about the sources of soil water for these forest
components. During early autumn in boreal forests, temperature falls and large events of rain are frequent which may influence soil water availability. To better understand the autumn plant-soil-fungi water relationships in this ecosystem, I used stable isotopes techniques in this
study to examine the water sources for ericaceous shrubs and fungi in a Scots pine forest following a large, early autumn rain event. I hypothesize that ericaceous shrubs of two functional groups (evergreen vs.
Föryngringsresultat och beräknad virkesproduktion i naturligt föryngrade tallbestånd i Västerbotten under mitten av 1990-talet :
According to the Board of Forestry, in Västerbotten, many natural regenerations of Scots pine (Pinus sylvestris) carried out on privately owned forest in the middle of 1990 in Västerbotten have rendered a bad regeneration outcome and will provide a low future forest production. The Board of Forestry believes that the negative result can be explained by the fact that the regeneration has been carried out in wrong locations and that scarification failed to work as planned. In order for an accepted rate of regeneration the guidelines of the Forrest Act require, not less than 10 years after final cutting at natural regeneration, that there should be at least 1300 (site indices 16 m) - 1700 (site indices 20 m) main crop stems per hectare. Main crop stems are defined as stems according to the place of growth and appropriate tree type, in addition with regard to quality, stage of development and damage risk have a prospect of succeeding. In addition main crop stems should be separated by surface so that the proportion sample plots with 3 meters radius, and lack main crop stems, are not more than 10 % of site indices 14 meters or higher.