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905 Uppsatser om Forest edges - Sida 11 av 61
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.
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.
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.
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.
Vegetationsutveckling och brandhistorik i Tyresta under 9000 år : en pollenanalytisk studie av en skvattramtallmyr i Tyresta nationalpark, Södermanland
Analyses of pollen and charcoal in peat cores, together with age-structure data of Pinus sylvestris from a Ledum-Pinus-mire in the Tyresta National Park (south-east Sweden) show the regional vegetation succession and fire history over the last 9000 years. Five major stages of mire development are identified: 1. Lake (c 7000-6400 cal BC); 2. Wet fen (c 6400-6000 cal BC); 3. Deciduous fen (c 6000 cal BC to c cal AD 700); 4.
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.
Köp av skogsfastighet : en fallstudie
The price of Swedish forest properties has gone up by 77 percent during the past five years. Amongst private forest managers the high price level signals optimism and confidence for the future.
Many forest owners manage large capital in the forest and a planned economy is to a larger extent demanded to achieve a positive economic result. Forest is long-term and to maximize a single year without planning for the years to come results in less optimization of the parameters available to achieve a favourable economic result.
This case study investigates the investment of two forest properties situated in Götaland.
The management of the forest has been planned for both properties during a period of ten years.
Local forest governance and benefit sharing from reduced emissions from deforestation and forest degradation (REDD) : case study from Burkina Faso
Africa is one of the regions most affected by climate change. However its forests are important carbon sinks for the whole world, and if recognised as a global public good, could be conserved and contribute to green house gas emission reductions. A global mechanism, Reduced Emissions from Deforestation and forest Degradation(REDD+) aims to help developing countries in reducing emissions from deforestation and forest degradation, and enhancement of carbon stocks. REDD+ strategies may, however exclude local forest dependent communities from forests in order to conserve and maximise carbon stocks, thus having a severe impact on local livelihoods. Therefore, how local communities can participate and share benefits from REDD+ is a key concern.This study investigates how three forest dependent communities in the Nazinon forest, in Southwest Burkina Faso could financially benefit from a REDD+ project.
Analys av linjetaxering i samband med gallringsinventering med avseende på kvalitet, tillförlitlighet och framtida utformning
Modern forest owners are very familiar with forest management and forest economics. Therefore they have high demands for quality in forest operations. Guarantee of quality in the shape of self-checking activities is an important tool to guarantee a well managed forestry operation. To meet the forest owners? demands on guarantee of quality and the entrepreneurs wish of an easy method for self-checking, the forest owners association, Södra skogsägarna, has developed a new method for thinning inventory.
The purpose of this study is to evaluate the method that is used for self-checking and to find ways to develop and improve of the method.
The data has been collected by inventory in a number of stands with circle-area survey and with strip survey, which is method that is used for self-checking.
The results show that the strip survey does not diverge more than ±10 % in measuring values of basal area, number of stems, roads share, thinning quotient, outtake of basal area and total volume compared to circle-area survey.
Clover (Trifolium spp) gamefields : forage production, utilization by ungulates and browsing on adjacent forest
Wildlife is a valuable and renewable resource that promotes economical, ecological and social values. These values are important for developing and maintaining many rural societies. However, growing ungulate populations have led to increased browsing pressure on valuable forest trees and crops. Previous studies have proposed supplementary feeding and gamefields as potential methods for controlling the ungulate foraging and reducing browsing damage by providing other attractive food resources. However, quantitative estimates of potential biomass production of various gamefield crops and browsing pressure on the surrounding forest have been lacking.
Skogsvård hos privata skogsägare : vilka åtgärder utförs och av vem?
Many participants in the Swedish timber market procure raw material from private forest owners. They often also offer forest services to ensure reforestation after final felling. Selling silviculture services can be a part of creating a long term relationship with the landowner for future timber purchases. The Swedish Forest Agency monitors forest rejuvenation results in the entire country. In the latest survey (2006 - 2008) the proportion of approved regeneration area was 78%.
Prestation i traktplanering
This study was an assignment for the company Holmen which is located in the region of Örnsköldsvik, Sweden. The study was focusing on the responsibilities of a forestry planner during the planning season.
The study was investigating about how much time the planner spent in the office, in the car and out in the forest. Any other issues that would cause delays were also identified. To be more effective and to increase the number of objects to a district bank, a better preparation in the planning stage (for thinning?s or clear cuts) is needed as well as faster transition on to the next area.
Hybridmodeller för prediktiv modellering skapade med genetisk programmering.
Det finns idag ett stort behov av att kunna klassificera stora mängder data på ett effektivt sätt. Prediktiv modellering är ett område inom data mining där prediktioner kan utföras baserat på tidigare erfarenheter. Dessa prediktioner presenteras sedan i en modell. Avvägningen mellan tolkningsbarhet och träffsäkerhet är ett begrepp som beskriver hur träffsäkra modeller ofta är ogenomskinliga, medan genomskinliga modeller ofta har lägre träffsäkerhet. Detta är ett problem eftersom det finns ett behov av modeller som är både träffsäkra och tolkningsbara.I denna studie visas hur man kan gå till väga för att skapa en modell som har en träffsäkerhet i klass med en ogenomskinlig modell, men samtidigt har en högre tolkningsbarhet.