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947 Uppsatser om Forest inventories - Sida 28 av 64

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.

Inventering och sammanställningav publikationer inom geovetenskaplig didaktik

This thesis presents a general definition of science education and earth science education.An inventory has been conducted of published material during the years 2011-2013, withthe start in 2013 and working backwards for international publications and with no timelimits in time for Swedish publications. Different databases were used during April 2013 forthe inventory.The thesis organizes and analyses published material in earth science education in a tablewith a following discussion.The purpose with the inventory was to investigate the amount and content ofprevious year?s publications in earth science education. Concept inventories were foundto be the most common subject of the found material, followed by virtual field studies. Thelargest amount of publications was published in North America.

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.

Urban green in Vientiane, Lao PDR : a minor field study

This is a Minor field study addressing the current situation in Vientiane, Laos where focus lies on the green structures past, present and future. The city of Vientiane is growing rapidly and as a result of this there is a increasing development. The once peaceful capital known for it?s lush and green environment is standing in a crossroad where important decision must be made to preserve valuable areas. During 8 weeks inventories and observations where made resulting into a proposal for future development. The proposal is divided into three parts. The urban fringe and surrounding landscape are still quite undeveloped and have a great potential of green wedges etc. The city of Vientiane and the green network linking important recreational, commercial and cultural places. Detailed proposal over certain green objects such as parks and squares..

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.

Skogsskötsel för att minimera stormfällning över järnväg :

The society of today is dependent of secure transports and deliveries of electrical power. Interruptions in different activities because of fallen trees cost a great deal of money in form of reparations and claimed damages for transport companies and electrical suppliers. Fallen trees along some railway sections are a severe problem. For instance, to repair the damages of the storm of week 5 year 2002, costed 2 800 000 SEK for the line region of Hässleholm. Today, the Banverket railroad company has no norms in general for how close to the railway the forest is allowed to grow.

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.

Lagerkostnadsarbete i teori och praktik: En fallstudie av lagerkostnader på ett sågverksföretag

This thesis investigates how inventory management is practiced at a Swedish sawmill company, how practice differs from theory in this field and how the company could make more use of this theory. To do this we have performed a study on relevant literature and compared our findings with a field study on Moelven Valåsen AB. Our analysis shows that a large gap between theory and practice exists. We identify several reasons to this, including some sector specific problems when calculating cost rate for timber inventories. Suggestions on solutions to these problems and an example of how a cost rate can be estimated with relatively simple means are presented.

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.

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