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9815 Uppsatser om Swedish forest - Sida 13 av 655

Samband mellan laserdata och fältdata

To make it easier for forestry planning the forest owners needs data which describe characteristics of the forest. Such data you usually get from some type of inventory. A relatively new technology which probably is getting more important in the future, is laser scanning because of lower costs. But because the laser technology is relatively new you need to compare it with conventional inventory technologies to get better understanding of the possibilities the laser technology gives. This work intends to estimate field measured characteristics of the forest from laser data with help of regression analysis and then see which of the field measured properties that best could be estimated and which laser variables that gave the best results. This study shows that heights has the best estimates, but biomass, diameter and volume also gives good estimates.

Realisering av en modulär skogsmaskin - En skalmodell

Wood for commercial use is harvested from forests using forest machines like harvesters which folds, branches and cuts trees and forwarders which transports logs to a landing area for further transport to a processing facility. Future forest machines have to be much gentler to the machine operators and forest soil than today's machines. Hence new machine solutions must be developed and tested. A practical way is to develop a physical scale model which can be used as a test-bed to incorporate different types of solutions for suspensions, cabin damping, tires and tracks, crane and overall architecture. The aim of this project was to develop such a 1:5 scale model of a forest machine, named as ?Skogbil.A scaling strategy was employed to arrive at important scale dimensions and specifications ofSkogbil which would be comparable to the full scale model.

Grey-sided vole and bank vole abundance in old-growth forest patches of different size and connectivity

Vole populations in northern Scandinavia vary in cycles with peaks every third or fourth year as described by the National Environmental Monitoring Programme of small mammals (NEMP). Some vole species have declined in population numbers since the NEMP started in 1971, especially the grey-sided vole (Myodes rufocanus) which is nearly extinct in the forested region. Since small mammals are an important food source for several avian and mammalian predators, the decline in vole numbers is expected to have consequences for the whole food chain, especially if other vole species start to decline in numbers. This study tried to test the hypothesis that presence and abundance of M. rufocanus (a specialist species) and Myodes glareolus (a generalist species) can be predicted by patch size and connectivity of forest patches >60 years old with a minimum of 15% pine >100years old.

Skiljer sig riskuppfattning och riskhantering mellan kvinnliga och manliga privata skogsägare? : en enkätundersökning bland privata skogsägare i Sverige

As a forest owner you always have to consider hazards and uncertainty when planning your forestry actions. The aim with this report is to test my hypothesis that there is an overall difference between men and women when it comes to perception, estimation and management of hazards/risks in forestry. I will look into if there are differences in how men and women estimate risks in production forestry from an economical point of view. The aim is also to look into if there are differences between male and female private forest owners, in how they perceive and manage hazards in connection with a possible climate change. To fulfil this aim, an inquiry survey was undertaken in three different areas of Sweden, two areas in the south and one in the north. But in this report I have evaluated the three areas as a whole.

Tätortsnära skogsrekreation : fallet Mösseberg i Falköpings kommun

Urban forests are important for people to get at break and be able to relax in a stressful world. Several studies show that we feel better through being out in the forest and historically this was the normal environment for us. As a result of population growth and urbanization we tend to spend less time in nature nowadays than before. Due to this development urban forests have become a central role in our society as a place where people can fulfill their needs and interests. The management of the urban forest is therefore important, especially for municipalities that own forest which is supposed to be of benefit to local residents.Falköpings municipality owns approximately 260 hectares of forest in the popular and most visited recreational area along Mösseberg?s southern slope.

Skogstillståndet och dess förändring i naturreservatet Lindbergska ytan i Mariestads kommun :

The aim of the study is to describe the state of the forest and changes in the Lindberg nature reserve. The study area is a nature reserve with an old coniferous forest, which has not been touched since 1950. The pines in the area have a very big diameter and are 150 ? 200 years old. The spruces are up to 150 years old.

Alla vill beta men ingen vill bränna : skogshistoria inom Särna-Idre besparingsskog i nordvästra Dalarna

In this work I have tried to reconstruct the forest history within Särna-Idre forest common in northern Dalarna from the 19th century until present time. The Särna-Idre region has been an extensively used landscape for a long time. Pollen which indicates grazing has been found in samples orginating from the 10th century. Early travellers from the 18th and 19th centuries seem to have been passing trough a "used" landscape. Burned forests on naked ground are described as common. Also large areas are mentioned as undisturbed with lots of large trees, snags and dead wood.

Tame animals in the wilderness : livestock grazing around summer farms in Jämtland, boreal Sweden 1800-2011

The forest and mire landscape surrounding the north Swedish villages have been of fundamental importance through time for the farmers. In the Scandinavian summer farm system the forest and mire pasture was used to its full potential. The system consisted of smaller summer farms some kilometres from the main farm in the village, and were the livestock grazed in the forest around the summer farm. The livestock affect their environment, and grazed forests generally contain a higher biodiversity than an ungrazed forest. The overall aim of this thesis is to understand the impact of livestock grazing on a northern forest ecosystem over a long time period.

Energieffektivisering av aerbo reningsprocess : Tillsats av biprodukter i skogsindustriellt avloppsvatten

In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.

Sveaskogs möjligheter att utveckla trädbränsleverksamheten i Västerbotten och södra Norrland :

This final thesis is initiated by the wood fuel department at the Swedish forest company Sveaskog as part of a project which also involves two other final thesises. The overall goal of the project is to investigate Sveaskog´s possibilities to produce and sell different wood fuel assortments in Västerbotten and the southern parts of Norrland. The aim of this thesis is to investigate how much wood fuel Sveaskog can produce in the area during the next five years and what that would cost. Furthermore the thesis will investigate the total possible supply of wood fuel from all other possible producers in the area. Treated assortments are forest residues from final fellings, whole trees from direct wood fuel thinnings, non industrial wood and industrial by-products from sawmills. The main effort to investigate Sveaskog´s production possibilities has been made to calculate the possible annual amount of forest residues and fuel from wood fuel thinnings that can be produced.

Felbegreppets tillämpning på skogsplantor

Uppsatsen behandlar felbegreppets tillämpning på skogsplantor. Lagstiftningen inom området skog och skogsplantor är relativt omfattande men skogsplantor är biologiska produkter varför lagstiftning inte helt kan förhindra att skador eller sjukdomar ändå uppstår. Det är helt enkelt inte möjligt att framställa skogplantor utan att en viss andel av dem är behäftade med fel. Då det är en mängd sammanverkande faktorer som kan bidra till skador eller plantors död kan det vara svårt att fastställa om orsaken till skadan/plantdöden var att hänföra till plantorna eller faktorer i uppväxtmiljön. Svårigheter att fastställa orsaken kommer därför bidra till svårigheter för skogsägarna i samband med reklamation.

Data och metodik för utbytesberäkning - en studie på Medelpads Skogsförvaltning

To manage the industry?s need of wood assortments in a optimal and cost effective way the forest companies need to have knowledge of the actual standing volume and the yield of the planned clear cuts. The mean volume of the trunk is also important since it is important for the contractors prices. Today the total volume are estimated either with Näslund (1940) or Brandels (1990) functions of volumes, and the yield is estimated with Rune Ollas (1980) function for trunks and stands. The purpose of this study has been to answer the following questions: How good is the yield forecast with data collected with currently used methods? How well can the yield forecasts became with data collected according to the instructions? How well can the yield forecast be with data collected according to the instruction and calculated with the program Aptan for theoretical bucking? The study has been initiated and financed by SCA Skog AB.The material consisted of a number of randomly selected objects ready for clear cut.

Spillningsinventering för bestämning av älgbetesbelastning på ungskog

In the 1980?s the moose population in Sweden grew explosively due to big changes in the silviculture with clear cuttings instead of single-tree selection. Clear cuttings brought big areas of young forest and therefore a lot of fodder in one place. Since this change, the discussion about how to manage the moose population has grown into a very big problem. Forest owners think that the population needs to be strongly reduced because of all the damage that is done to the young forest when the moose seeks its food, and the economic losses because of that.

Gödslingsstrategins inverkan på Holmen Skog, Umeå distrikt

This thesis analyzes the effects of different fertilization strategies on forest management at Holmen Skog in Umeå district. Harvesting volumes, net present values and fertilization intensity are presented for each fertilization scenario. The planning reserve (percentage area older than minimum final felling age) was also analyzed in this study.The thesis covers the analysis of five different fertilization scenarios, varying in fertilization intensity, from no fertilization at all, to fertilization at every harvesting operation (thinning or final felling). A sub-study was also carried out so the reader in detail can see how the different fertilization scenarios affect individual forest stands of different nature. The analysis has been done with the planning tool PlanWise, which is an application of the Heureka analysis and planning system.

Historisk markanvändning på Färsna gårds inägor och utmarker

Semi-natural grasslands are threatened biotopes in the landscape and without conservation measures high values of nature will be lost. Meanwhile, the biological values associated with cultural values of the traditional agricultural landscape in Sweden. Studies of land use history may help to understand how today biological diversity has evolved and how it can be preserved. Färsna farm in Norrtälje has left some of the old heritage of biological diversity in the form of nature - forest and grassland, which hosts an unusual herb-rich flora. Through the study of historic maps and från1673/1767/1801/1901 1952 and orthophoto of the area has a picture of how land use has changed over time emerged.

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