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993 Uppsatser om Forest fuels - Sida 49 av 67
A comparison of methods to assess site index in young Norway spruce stands
This study investigates whether the site index curve method (SICM) and the growth intercept method (GIM) can be used for site index predictions in younger Norway spruce (Picea abies (L.) Karst.) stands than recommended by current guidelines. For SICM it was thus investigated whether the method could be used for stands younger than ten years, and for GIM it was tested whether a starting point for the intercept measurements could be used below the recommended
2.5 meter. This was tested based on measurements taken from experimental stands in Tönnersjöheden Research Forest.
For GIM it was found that the method can only be used when the TH-trees of a stand have five complete intercepts above 2.5 meters. For the method to be applicable beyond this, it will be necessary to adapt the underlying equations, perhaps following the Canadian example where a 1.3 meter intercept start is used. In conclusion it is not currently possible to apply the approach beyond the current recommendations.
For SICM, SI predictions are accurate for the study area already form year three.
Mjölkraskorsningar i avelsvärdering av tillväxt hos svenska köttrastjurar
The concerning issue of declining number of hunters in North America is also apparent in Europe and Sweden. When the bulk of research found on human dimensions and hunting participation has almost exclusively been done in the United States, this report seeks to add to the needed knowledge on a national level focusing on the causes of hunter declines related to social factors within Sweden. Using hunter data reaching from commune, county to National level, this report describes the correlation between a number of variables and the hunting participation in Sweden.The typical Swedish hunter lives in an area with low population density, the person usually has higher education, the living situation is stable with no recent moving and there is relatively good access to forest land. Persons with weaker connection to the Swedish culture such as foreign citizens, people with foreign background and people born outside ?the Nordic countries? are less likely to start hunt or participate in hunting.A strong relationship was found between the favorite game, moose (Alces alces), and the amount of hunters participating in the hunting.
Naturhänsyn på slutavverkade hyggen i Östergötlands län.
95% of the productive forest land in Sweden are now being exploited for forestry. The new Forestry Act of 1993 equate the goal of production and the environmental goal which means that the objective for forestry is a sustainable yield, while the biological diversity must be preserved. Recent years results from the inventories of the Board of Forestry show declining trends in how nature conservation aspects taken into consideration at the felling sites.The aim of this study is to investigate what happends with the nature consideration taken at felling sites in the long run. 20 final fellings in the county of Östergötland were re-inventoried 7-9 years after final felling. These felling sites had previously been inventoried before final felling (P0) and one year after final felling (P1) in the inventory Polytax by the Board of Forestry.
Towards sustainable rye cultivation : soil carbon and yield modelling for crop rotations with rye
Using the Introductory Carbon Balance Model, ICBM, five different crop rotations with rye
1. Rye-Ley-Ley-Rye-Beans-Rye
2. Rye-Rye-Rapeseed-Rapeseed
3. Rye-Ley-Ley-Rye-Potatoes-Rye
4. Rye-Rye-Potatoes-Wheat
5. Rye-Rye-Potatoes-Beans-Wheat-Rye-Potatoes-Rapeseed
were tested theoretically in four different cultivation scenarios
? Straw left on the field, biogas digestate added as fertilizer. Labelled ?+straw+BD?.
? Straw left on the field, only synthetic fertilizer. Labelled ?+straw-BD?.
? Straw harvested, biogas digestate added as fertilizer.
Användning av rötrest från kombinerad etanol och biogasproduktion : en jämförelse mellan tre alternativ
Scandinavian Biogas is involved in the planning of a combined ethanol and biogas factory in Karlskoga, Sweden. Besides biogas and ethanol large amounts of digester residues will be produced, about 450 000 liquid tonnes residue (~7,3 % Dry Substance( DS)). The objective of this thesis was to investigate possible uses of the residue from the biogas production process ScandgasEthanol developed by
Scandinavian Biogas, and to derive a methodological approach how to evaluate and compare handling systems. Three systems where proposed and compared in this thesis; spreading of the untreated residue as fertilizer (system 1), dewatering to a higher DS content to reduce transportation before spreading as fertilizer
(system 2) and production of a solid fuel by dewatering and drying the residue (system 3). The general conditions for the proposed systems were investigated in
terms of practical viability, economical aspects, environmental impact and energy inputs/outputs.
Integrering av kommunikation i ingenjörsutbildningar : Ett underlag för kompetensutveckling för universitetslärare vid KTH
The sun is an endless energy source and the heat it produces can be used to heatup our homes. This technology is relatively old and was introduced in the late70-s. There are two kinds of solar collectors that are most frequently used todayand these are plain solar collectors and vacuum solar collectors. The plain solarcollectors are the once that are used the most but the vacuum solar collectorshave increased more as a percentage the last couple of years.The biggest question asked regarding an investment in solar heating is if theplant is economically profitable. This question has no direct answer because itis dependent on a couple of prerequisites.
Metodutveckling för planering och genomförande av dikesrensning med moderna metoder
?Development of methods for the planning and implementation of ditch clearing with modern methods?, is a long title for an exam work but that is what this report describes.
In Sweden, we have a limited area available, and with the present development with increasing market oil prices, and enormous forces on the renewable energy sources, we need every hectare possible to protect the output of the forests.
So with this in mind, many people are now considering how to increase the production of the forests that are already available. A part of production increases is to manage the existing forests, and not to allow this area to go to cultivation or become marshland.
We manage our forests in a way that benefits the environment, and we consider that our working practice over the years has shown us to be correct and well functioning.
A part of our way of producing forests is to ensure that we have functioning drainage systems in the forest holdings which we administer. The responsible at Holmen Skog requested a good method to make inventories of the drainage systems of Holmen forests.
This Degree Project is about ways to identify and implement drainage systems with modern methods. It deals with authorities regulations, and how they operate in different counties.
Kulturmiljöhänsyn inom skogsbruket : En studie om fornlämningar och gränsmärken
Bakgrund Skogsmaskiner har under många år förstört både fornlämningar och gränsmärken. Idén till databasen/tjänsten uppkom av egna erfarenheter vid en förrättning, där flertalet gränsmärken hade blivit överkörda av skogsmaskiner. Syfte Examensarbetets syfte är att lyfta fram en ny idé för att minska skadorna på fornlämningar och gränsmärken som skogsmaskiner orsakar, samt hur lägesnoggrannheten påverkar den nya tjänstens ändamål.Metod Examensarbetet består av en litteraturstudie med syfte att besvara och ge en bakgrund till problemställningen. För att undersöka hur vanligt det är att lantmätare/mätingenjörer stöter på att gränsmärken blivit skadade av skogsmaskiner genomfördes en enkätundersökning. För en djupare inblick av lägesnoggrannheten på utrustningen i skogsmaskiner och vilken kvalitet på koordinaterna som krävs för en mer ändamålsenligt tjänst gjordes en intervjustudie.Slutsats De uppgifter som finns tillängliga idag ska vara användbara när det gäller fornlämningar, för en ändamålsenlig tjänst som ska fungera ute i skogen där lägesnoggrannheten inte alltid är den bästa.
Planteringsförbandets inverkan på bestånd av contortatall (Pinus contorta var. latifolia) med avseende på volymtillväxt och virkesegenskaper
At the beginning of the 1970´s forestry feared an imbalance in the future wood supply. Because of this anticipated "timber slump" forest companies undertook a variety of measures to counter this. One of these measures was the introduction of exotic tree species. The choice finally ended up with lodgepole pines which were considered a fast growing tree species compared to our native tree species. Theambition for the new lodgepole pine stands were to run these with rotation periods of between 40-60 years, thus smoothing out the ?timber slump? that was anticipated.
Dubbskador på Alvestakubb
Mechanical harvesting may result in timber damages leading to reduced saw log quality. The initiator of this study was VIDA ? a privately owned concern operating in the value-adding process industry of forest raw materials. The aim of this study was to examine the type and amount of damages on Alvestakubb caused by the harvester head during the cutting process. The aim was also to compare the damages caused by different types of feed rollers and to evaluate the effects of temperature on damage occurrence.
Köpares syn vid förvärv av lantbruksfastighet i Dalarnas och Gävleborgs län
Today's real estate buyers value the purchase different today compared to a decade back. Previously it was the return value that ruled the market. This has created problems when the broker must allocate the purchase price of the property's various elements, because non-monetary values such as forest for leisure, recreation, and the feeling of owing has increased in recent years and an increasingly important part in the valuation process.
The assessed value can be a guide, but is perceived today to be stereotyped to put a fair value at the individual item.
The purpose of this study was to provide the real estate agent decision support and a guide to the likely value of accounting for the purchase price.
The report is written on behalf of LRF Konsult. The result is based on a questionnaire survey which was conducted in June 2014 among all those who had bought a farming property in Dalarna and Gävleborg province mediated by LRF Konsult in 2013.
The report was made with a split to see if the valuation and motives differ between new and previous owners. It was possible to see a big difference in the reason for the purchase, where a large share of new owner bought the land for capital investment, in contrast to previous owners whose biggest group bought for an active use.
At several points it was possible to identify a higher non-monetary value of the new owner from the previous landowner.
Elementkoncentrationer i gran utmed en markfuktighetsgradient :
One key factor in silviculture today is sustainability. In order to achieve sustainability it may be important to restore lost nutrients to the forest after clearcutting. In order to calculate the removal, you need to know how much of different elements you will find in different tree compartments. The aim of this study was to investigate if the concentration of elements in different tree compartments of spruce (Picea abies (L.) Karst) were related to the moisture conditions of the site. Five plots at Risfallet (60º 21´ N, 16º 13´ E), was placed along a moisture gradient in a 40- year spruce stand.
SÖDRAs Gröna Skogsbruksplaner : en uppföljning relaterad till SÖDRAs miljömål, FCS's kriterier och svensk skogspolitik
SÖDRA beslutade 1995 att starta ett projekt för att förse föreningens medlemmar med
naturvårdsanpassade skogsbruksplaner. Projekt "Gröna skogsbruksplaner" har som mål att
fram till år 2002 täcka halva medlemsarealen med gröna planer, och har för att nå detta givits
en budget på 50 miljoner kronor. Konceptet med grön plan är ursprungligen skapat av
skogsvårdsorganisationen, men SÖDRA är först med att producera gröna planer i stor skala.
De gröna planerna skall enligt projektets syfte "ge SÖDRAs medlemmar ett verkningsfullt
redskap for virkesproduktion med hänsyn till de miljömål som finns formulerade i SÖDRAs
miljöpolicy". Detta är ett led i det miljöengagemang som på senare år ökat i Sverige.
Kapsprickor och avverkningsaggregat
This study was made for the Swedish forest company Sveaskog because the sawmills they delivered timber to had noticed a high frequency of bucking splits in their products. Coworker Jim Edström at Sveaskog also wanted to know if there was a big difference between different felling heads. The purpose with this study has been to find out the amount of bucking splits and if there is any felling head brand that did a bigger damage that the others.
The study was made in two steps, where the first part was a literary review to find out results and conclusions in earlier studies. The best measuring method to check bucking splits was the known ?trissmetoden?.
Jämförelse mellan renskötsel och betesbaserad fårskötsel
This essay describes and compares the extensive reindeer management to the more intensive, but grazing based, sheep management system in Sweden. Differences and similarities between the two production systems will be investigated by elucidating the economy, land use and possibilities to influence production and economy through breeding, feeding and product development. The reindeer management area covers the northern part of Sweden whilst the sheep management is dispersed over the country. Both reindeer and sheep are ruminants and have relatively high demands on the quality and digestibility of the feed however reindeers graze on mountain-and forest lands whilst sheep often graze inaccessible areas or cultivated grasslands. Selection intensity is generally lower in the reindeer management compared to the intensity in sheep breeding.