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1177 Uppsatser om Forest fuel - Sida 19 av 79
Kostnader för jordbearbetning och sådd :
Syftet med detta examensarbete är att sammanställa maskinkostnader för etableringsmetoderna plöjningsfritt och konventionellt. Vi vill även titta på hur stor kapacitet som behövs på maskinparken för den tänkta gården på 600 ha åker, detta för att hinna etablera grödan inom ett rimligt tidsspektra. Anledningen till att vi valt ett företag på 600 ha är att det är den areal tröskan klarar av att avverka inom rimlig tid. Det medför att vi måste ta en del hänsyn till lägligheten och hur mycket av tiden som är så kallat ?tjänligt väder?.
Gestaltningsförslag för Bölekläppen : utveckling av upplevelsevärden i ett friluftsområde i Umeå stads utkant
Taking a qualitative approach, this research investigates different theories and methods for creating parks that people will cherish and visit during their daily life. It also takes on the task to understand how principles of developing recreational values in a small forest is affected by the addition of a new element to the landscape, i.e. a major highway. Data was collected through the combination of focused literature review and study trips. This provided a framework which in turn was applied to the subject of the study, i.e.
Biomass losses during short-term storage of bark and recovered wood
Storage of biomass is associated with problems like heat development, biomasslosses, and reduction of the fuel quality. Certain processes such as biological- andchemical degradation are responsible for these storage problems. This master?sthesis was carried out at Vattenfall Research and Development AB and is alignedtowards quantifying the biomass losses from short-term storage (1-2 months) ofbark and recovered wood. The biomass was stored in outdoor piles during differentseasons, campaign 1 (summer) and campaign 2 (autumn).
Svamparnas roller i svenska barrskogsekosystem : hur ser kunskapsläget ut hos några olika grupper människor?
Fungi are everywhere around us and recently, there has been
an increased interest in their role and importance in the forest.
The fungi have several strategies to acquire energy and nutrition; one example is a mutual symbiosis with trees and plants - another being dissolving organic materials.
Attempts have been made to better understand the circulation of nutrition in coniferous forests, and how fungi cooperate.
Trees and plants have adapted with mycorrhizae and are now interdependent which is important to consider in forestry.
A great number of fungi depend on dead wood and old trees to set fruiting bodies and spread further. These fungi also create environments for other species, such as birds and insects.
The vegetation of a forest is determined by a series of factors; tree species, how old the forest is, soil type, as well as the ability of the fungal spores to spread and establish. Furthermore, in determining vegetation, the fungi?s ability to compete in the soil matters. These factors are nearly unexplored.
Researching fungi knowledge and interest, a survey was distributed to five groups of people.
The groups included forest owners, high school teachers, high school students, senior citizens, and a fifth group - ?o he ? - consisting of people of mixed ages and backgrounds.
En jämförelse avseende beståndsgående-och stickvägsgående gallringsmaskiner
The purpose of this report is to investigate and compare the difference between stand-thinning machines and strip-road thinning machines, and how they affect the stand on behalf of future growth, theoretical economic result, wind impact, snow pressure and density of stand.
The investigation is regarding the first commercial thinning of pine stands, after pre-commercial thinning that was well conducted.
The investigation area was located near Katrineholm, Sweden. The measurements that were measured were strength of thinning and amounts of wind throws, snow-breaks and hauling damages.
The results that emerged, was that thinning with strip-road machines had a significantly higher strength of thinning over all, as compared with the stand- thinning machines (45 percent versus 30 percent).
Comparisons between wind-throws, snow-breaks and hauling damages of the stand could not establish any significant differences between the two methods that were investigated.
Conclusions, over all, were that if forest owners want to have more timber volume left for second thinning and final cut of the stand, the forest owners should choose the method with stand-thinning machines. From the point of view of gentle treatment of the stand and ground damages the choice should be the same.
However, the method with strip-road thinning machines is the most common and accessible method in Sweden. Most likely it is the most economical way to manage the stand for forest owners in present time.
If the method with stand-thinning machines is becoming more common in Sweden, it is suggested for forest owners to consider the stand-thinning method as a candidate for treatment due to economic aspects..
Habitat use and ranging behaviour of GPS tracked juvenile golden eagles (Aquila chrysaetos)
Throughout its wide distribution in the northern hemisphere, the golden eagle occurs in a diverse range of environments, e.g., mountainous, forest and open areas. The literature on juvenile golden eagles is limited, and this study provides further knowledge on habitat use and ranging behaviour during the post-fledging period in boreal Sweden. A total of 14 golden eagle juveniles were tagged with GPS transmitters during 2010 and 2011, and nine could be followed during the entire post-fledging period from fledging until migration.
The juveniles fledged at the end of July and beginning of August and initiated migration during October and beginning of November. The length of the post-fledging period, until migration started, ranged from 49 to 97 days. During this period, the juveniles? distance from their natal nest and their GPS height increased with time as their flying abilities developed.
FSC certifiering vid BioEnergi i Luleå AB: livskraftigt bruk
av världens skogar
Bakgrunden till detta arbete är att Bioenergi i Luleå AB måste tillmötesgå kundkraven för att behålla sina marknadsandelar och ha möjlighet att utöka dessa. På senare tid har de stora kunderna börjat efterfråga bränslepellets som är certifierad enligt Forest Stewardship Council, FSC. Examensarbetets syfte var att hjälpa Bioenergi med framtagandet av en Forest Stewardship Council Chain of Custody certification. I den inledande kartläggningen användes i huvudsak intervjuer och observationer för att studera de anställda och tillverkningen. För att identifiera aktiviteter och brister i Bioenergis system studerades även interndokumentation och relevant litteratur.
Energianalys av etanolproduktion : en fallstudie av Lantmännen Agroetanols produktionssystem i Norrköping
In this thesis an energy analysis of ethanol production at the ethanol plant of
Lantmännen Agroetanol in Norrköping has been performed. The ethanol plant has
been studied in combination with Händelöverket, the combined heat and power
plant which provides the ethanol process with steam. The purpose of this study
was to determine the energy consumption for the whole production chain from
grain to ethanol. The analysis has included the energy consumption for cultivation
of grain, production of chemicals, the production chain for wood chips, the steam
production and the ethanol plant. The grain and wood chips are both considered
raw materials there for the energy content in these are not included as energy input
in the system.
Energianalys av etanolproduktion : en fallstudie av Lantmännen Agroetanols produktionssystem i Norrköping
In this thesis an energy analysis of ethanol production at the ethanol plant of
Lantmännen Agroetanol in Norrköping has been performed. The ethanol plant has
been studied in combination with Händelöverket, the combined heat and power
plant which provides the ethanol process with steam. The purpose of this study
was to determine the energy consumption for the whole production chain from
grain to ethanol. The analysis has included the energy consumption for cultivation
of grain, production of chemicals, the production chain for wood chips, the steam
production and the ethanol plant. The grain and wood chips are both considered
raw materials there for the energy content in these are not included as energy input
in the system.
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.
Vederlagsgrundande mätning med skördare
This study was performed in collaboration with Moelven Skog AB, Örebro district. The purpose of the study was to review existing literature in order to describe the current status of harvester based measurement technology as the way to provide information for calculating payment to the forest owners. In addition to this, a short survey was conducted to find out how a switch to harvester based measurement would affect the administrative workload on timber purchasers working for the district.
The literature study shows that the harvester measurement technology is ready to use if it is combined with well-established routines for control of the harvesters, methods for automatic quality indexing of the timber and ways of creating pricelists specially adapted for harvester measurement. Pricing each stem seems to be the most promising method. Stem pricing has several benefits.
Liquid diesel biofuel production in Sweden : a study of producers using forestry- or agricultural sector feedstock
The transportation sector is the only sector of the Swedish society that is still increasing the emissions of carbon dioxide and other green house gases. Diesel fuel represents one of the fuels that contributes to these emissions and the use of diesel fuels is increasing every year. The main purpose of this study was to make an estimation of the current business situation for producers of liquid diesel biofuels in Sweden such as biodiesel, synthetic diesel and crude tall diesel and examine the forces of competition of the industry today and its future prospects. The study revealed that the rivalry among the existing firms was low mainly due to the geographical spread of the companies. Moreover the success of the biodiesel industry was influenced by a long-term guarantee of the tax exempt for biofuels and by the price level of petroleum diesel.
Följdeffekter av olika användningssätt för vedråvara : en ekonomisk studie
Since the turn of the millennium a sharp increase in the interest for bio energy has been observed. Important reasons for this growing interest can be due to the fact that fossil fuels are a finite resource. A net discharge of greenhouse gases occur when fossil fuels are burned. The discharge of greenhouse gases are considered to be the main reason to the greenhouse effect. Means of control to increase the use of bio energy has been introduced and, as intended, the use of bio energy has increased.
As a result of the legal provisions the ability to pay for bio energy has increased, which the forest industry view as a problem.
Tätortsnära skogsbruksplan i Borås stad
This report is part of an Bachelor of Science work in forestry, conducted for the community of Borås, Sweden. In order to create a forest management plan for the area of Hestra, a survey was conducted. People living in the area were given the opportunity to reply to the survey. The questions in the survey are both personal and forestry-related. The aim is to reach out to the different categories of people when it comes to age, living and the different aspects of visiting the woods.
Kommunägd skog i Sverige : en enkät- och intervjustudie av de tätortsnära skogarnas ekonomiska och sociala värde
This Masters thesis is performed at the request of the National Board of Forestry in order to investigate how the Swedish municipalities use their forests. The study is of general character with emphasis on the social values of the forests.
The municipalities? purposes with their forests have varied over time, but lately the social aspects have been recognised as interesting. The social values of the forests can be defined as the values from the forests that contribute to the wealth of humans. This has socio-economic importance for the municipalities.
The study was performed as a quantitative questionnaire survey, complemented with qualitative interviews.