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1067 Uppsatser om Forest fire - Sida 14 av 72

Bättre åtkomst till avverkningstrakter med anpassat marktryck från avverkningsmaskinerna

The global climate-change means increasing mean-temperature and higher precipitation in Sweden, which leads to shorter periods of frozen ground in the forest. At the same time the harvesting machines are getting bigger and more powerful. The forest industry aim at an even wood flow, and the ground damage has to be as low as possible. The two biggest causes for ground-damage is the bearing capacity of the forest ground and the ground-pressure of the harvesting machines. The aim of this study was to find out some rules for the machine choice considering ground pressure, when harvesting on ground with low bearing capacity.A field study, using a Valmet 890.3 forwarder, was carried out where different ground pressures and their effect on the ground were tested on two different types of ground.Additionally, an inventory of damaged harvesting grounds was made.

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.

Generell hänsyn vid avverkning : påverkan av dispens från sexveckorsregeln samt skogsägares kunskap, tankar och åsikter

The forests in Sweden have, for a long time, been managed intensively. This has led to even-aged stands with few tree species and a lack of dead wood. Therefore, general conservation measures in connection with regeneration felling are important in order to promote biodiversity. Inventories carried out by the Swedish Forest Agency, however, show that about 25 % of the felled area does not reach the level of the Forestry Act, regarding general conservation measures. The aim of my study was to see whether exemptions from the six week notice of reporting regeneration fellings (the Forest Agency demands a report six weeks in advance of fellings), affect the results of the general conservation measures taken.

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.

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.

Trakthyggesfria skogsbrukssätt : kunskap, förutsättningar och attityder

Forestry has three main aspects to take into consideration today; economical, ecological and socio-cultural. In order to reach the broad policy goals for sustainable forest management, an increased variety of management approaches are requested. Today clear-cutting is the only method used in 96 % of the managed forests in Sweden. The Swedish National Board of Forestry has therefore initiated a project in order to investigate and develop Continuous Cover Forestry (CFF). This study is a part of this project.

Viktiga egenskaper hos framgångsrika svenska skolskogar :

A substantial part of the Swedish outdoor education is being practiced in so called ?school forests?. The concept school forest was first introduced in the 1980?s by the organization Skogen i Skolan. The definition of a school forest is an area that is being used for educational purposes, over which the school and the land owner has reached an agreement of how the school may utilize it.

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.

?Horan, knarkaren och fettots fortsättning?? : En queerfeministisk analys av de normbrytande personligheterna i romanen Eld

Engelfors Trilogy is a three-part fantasy novel consisting of Circle, Fire and The key, written by Mats Strandberg and Sara Bergmark Elfgrens. Circle was nominated for the August Prize award 2011, which is a literary prize awarded each year. The book has also been translated into 25 different languages. Fire came out in August 2013 and is the part of the novel that I will concentrate on in these theses. What I will do in this paper is a queer feminist analysis of the novel's main characters in the book Fire.

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.

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.

Exercise pens as an environmental enrichment for laboratory rabbits

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.

Beslutsunderlag för energianpassade gallringar i Västerbotten

The demand for renewable energy is increasing in Sweden. This consequently increases the pressure for and willingness to pay for forest fuels. One method to extract forest fuel from suitable commercial thinnings is the "long top method? (LT-method). With this method saw logs and non-delimbed tops are recovered, i.e.

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